The Effect of Domiciliary Professional Oral Care on Root Caries Progression in Care-Dependent Older Adults: A Systematic Review

With care dependency, untreated root caries lesions (RCLs) and irregular dental visits are common. RCLs, if left untreated, could lead to pain, tooth loss, difficulties eating, and impact on general health. Therefore, there is a need for prevention and effective treatment for RCLs, and especially in those with care dependency. The aim of this systematic review was to investigate the effect of domiciliary professional oral care on root caries development and progression, in comparison with self-performed or nurse-assisted oral care. A literature search was conducted in four databases in November 2022. Two authors independently screened the literature throughout the review process. Five of the identified studies were found to be relevant. Four of these were assessed as having moderate risk of bias and were included in the review, while one study had high risk of bias and was excluded from further analyses. Due to heterogenicity of the included studies (and of the interventions and outcomes), no meta-analysis or synthesis without meta-analysis (SWiM) was performed. The participation of dental personnel performing mechanical plaque removal and fluoride, or chlorhexidine application seems beneficial for care-dependent older adults with risk of RCLs development and progression. However, future studies are needed.


Introduction
Among care-dependent older adults living in nursing homes, the number of untreated root caries lesions (RCLs) is high [1,2]. A systematic review by Zhang et al. [3] discovered several risk predictors for developing RCLs. The risk predictors stated were the age of 60 years or older, having poor oral hygiene, smoking, gingival recession, low socioeconomic status, and previous dental caries experience [3]. The risk for developing RCLs increases with age due to gingival recession caused by age and/or periodontal disease leading to exposed root surfaces [4]. RCLs are located on exposed roots of teeth and are of two categories. The first category is shallow and saucer-shaped and can be healed mechanically by toothbrushing with fluoride toothpaste [5][6][7]. The second category has the same shape as the first but is deeper and should be restored because of the risk of pulp exposure [7]. Bashir [8] reports a prevalence of untreated root caries among independent adults aged

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3. Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included studies, by domain and conclusive judgement.
Tan, Lo, Dyson, Luo, and Corbet [55] 2019 2002 2020 2010 ry Germany Great Britain Sweden China Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; studies were conclusively deemed to have moderate RoB; the fifth study had high ( Table 2). Only the results from the studies with a moderate RoB were further anad. The characteristics of these four included studies are summarized in Table 3.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
pact of g, pers by a number root car--term rs, comwhose formed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3. Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included studies, by domain and conclusive judgement. Great Britain Sweden China y of regular profesbrushing by a dental for 3 months in nursing residents-a randomontrolled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders. estigate the impact of sional brushing, perd every 2 weeks by a nurse, on the number h, incidence of root card further short-term alth parameters, comwith residents whose giene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Great Britain Sweden China Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; lyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed u five studies were conclusively deemed to have mod RoB (Table 2). Only the results from the studies with lyzed. The characteristics of these four included stud  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domicilia sional oral care for pendent elderly in homes-oral hygie bleeding, root carie ing staff's oral hea knowledge and att Aim To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the eff ing home residents sional cleaning, an OHIs provided by dental hygienists, son with daily oral usual.
five studies were conclusively deemed to have moderate RoB; the fifth study ha RoB (Table 2). Only the results from the studies with a moderate RoB were furth lyzed. The characteristics of these four included studies are summarized in Table   Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five i studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on ies prevention in elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effecti the following four met preventing new root s caries: (1) only OHIs every 3 (2) OHIs and applicati Cervitec varnish every months; five studies were conclusively deemed to have moderate RoB; the fi RoB (Table 2). Only the results from the studies with a moderate RoB lyzed. The characteristics of these four included studies are summariz  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A rando ies prev

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To comp the follo prevent caries:

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out o five studies were conclusively deemed to have moderate RoB; the fifth study had hig RoB (Table 2). Only the results from the studies with a moderate RoB were further an lyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root ca ies prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness the following four methods in preventing new root surface caries: (1) only OHIs every 3 months (2) OHIs and applications of Cervitec varnish every 3 months; five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Great Britain Sweden China Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; five studies were conclusively deemed to have moderate RoB; the fifth study ha RoB (Table 2). Only the results from the studies with a moderate RoB were furth lyzed. The characteristics of these four included studies are summarized in Table   Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five i studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on ies prevention in elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effecti the following four met preventing new root s caries: (1) only OHIs every 3 (2) OHIs and applicati Cervitec varnish every months;

Risk of Bias
The five included RCT s five studies were conclusively RoB ( Table 2). Only the result lyzed. The characteristics of th Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the com of chlorhexidine/thym fluoride-containing va on the severity of RCL institutionalized elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effec oride-containing varn protector) in combina either Cervitec or a pl nish on the clinical ch tics of existing RCLs. [53] cluded RCT studies were assessed using the RoB 2 tool [31]. Four out of e conclusively deemed to have moderate RoB; the fifth study had high nly the results from the studies with a moderate RoB were further anacteristics of these four included studies are summarized in Table 3.

Brailsford et al., 2002
nt of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included n and conclusive judgement. Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.

Deviations from the intended interventions
A randomized trial on root caries prevention in elders.
etermine the effect of a flue-containing varnish (Fluor ector) in combination with r Cervitec or a placebo varon the clinical characterisf existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW 6 of 14

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out o five studies were conclusively deemed to have moderate RoB; the fifth study had hig RoB (Table 2). Only the results from the studies with a moderate RoB were further an lyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root ca ies prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness the following four methods in preventing new root surface caries:

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31] five studies were conclusively deemed to have moderate RoB; the fifth stu RoB (Table 2). Only the results from the studies with a moderate RoB were lyzed. The characteristics of these four included studies are summarized in T Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of th studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized ies prevention i

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the the following fo preventing new caries: (1) only OHIs e (2) OHIs and ap Cervitec varnis months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Fou five studies were conclusively deemed to have moderate RoB; the fifth study ha RoB (Table 2). Only the results from the studies with a moderate RoB were furth lyzed. The characteristics of these four included studies are summarized in Table   Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five i studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on ies prevention in elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effecti the following four met preventing new root s caries: (1) only OHIs every 3 (2) OHIs and applicati Cervitec varnish every months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW

Risk of Bias
The five included RCT s five studies were conclusively RoB (Table 2). Only the result lyzed. The characteristics of th   Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the com of chlorhexidine/thym fluoride-containing va on the severity of RCL institutionalized elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effec oride-containing varn protector) in combina either Cervitec or a pl nish on the clinical ch tics of existing RCLs.
Girestam Croonquist et al., 2020 [54] cluded RCT studies were assessed using the RoB 2 tool [31]. Four out of e conclusively deemed to have moderate RoB; the fifth study had high nly the results from the studies with a moderate RoB were further anacteristics of these four included studies are summarized in Table 3.
nt of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included n and conclusive judgement. Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.

Deviations from the intended interventions (effect of assignment to intervention) Deviations from the intended interventions
A randomized trial on root caries prevention in elders.
etermine the effect of a flu--containing varnish (Fluor ector) in combination with r Cervitec or a placebo varon the clinical characterisf existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; 6 of 14

isk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of studies were conclusively deemed to have moderate RoB; the fifth study had high ( Table 2). Only the results from the studies with a moderate RoB were further anad. The characteristics of these four included studies are summarized in Table 3. e 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included es, by domain and conclusive judgement.

Deviations from the intended interventions (effect of assignment to intervention)
Deviations from the intended interventions The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
pact of g, pers by a number root car--term rs, comwhose formed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; PEER REVIEW 6 of 14

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Great Britain Sweden China y of regular profesbrushing by a dental for 3 months in nursing residents-a randomontrolled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders. estigate the impact of sional brushing, perd every 2 weeks by a nurse, on the number h, incidence of root card further short-term alth parameters, comwith residents whose giene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months;

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Great Britain Sweden China Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW

Risk of Bias
The five included RCT studies were assessed using the RoB five studies were conclusively deemed to have moderate RoB; RoB (Table 2). Only the results from the studies with a modera lyzed. The characteristics of these four included studies are sum  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A i

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.

Risk of Bias
The five included RCT studies were assessed u five studies were conclusively deemed to have mod RoB (Table 2). Only the results from the studies with lyzed. The characteristics of these four included stud  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domicilia sional oral care for pendent elderly in homes-oral hygie bleeding, root carie ing staff's oral hea knowledge and att Aim To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the eff ing home residents sional cleaning, an OHIs provided by dental hygienists, son with daily oral usual.

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Fou five studies were conclusively deemed to have moderate RoB; the fifth study ha RoB (Table 2). Only the results from the studies with a moderate RoB were furth lyzed. The characteristics of these four included studies are summarized in Table   Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five i studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on ies prevention in elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effecti the following four met preventing new root s caries: (1) only OHIs every 3 (2) OHIs and applicati Cervitec varnish every months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW

Risk of Bias
The five included RCT s five studies were conclusively RoB (Table 2). Only the result lyzed. The characteristics of th   Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the com of chlorhexidine/thym fluoride-containing va on the severity of RCL institutionalized elder

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effec oride-containing varn protector) in combina either Cervitec or a pl nish on the clinical ch tics of existing RCLs.

Tan et al., 2010 [55]
6 of 14 cluded RCT studies were assessed using the RoB 2 tool [31]. Four out of e conclusively deemed to have moderate RoB; the fifth study had high nly the results from the studies with a moderate RoB were further anacteristics of these four included studies are summarized in Table 3.
nt of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included n and conclusive judgement. Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.

Deviations from the intended interventions (effect of assignment to intervention) Deviations from the intended interventions
A randomized trial on root caries prevention in elders.
etermine the effect of a flu--containing varnish (Fluor ector) in combination with r Cervitec or a placebo varon the clinical characterisf existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW 6 of 14

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3. Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five included studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW 6 of

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out o five studies were conclusively deemed to have moderate RoB; the fifth study had hig RoB (Table 2). Only the results from the studies with a moderate RoB were further an lyzed. The characteristics of these four included studies are summarized in Table 3. Table 2. Assessment of risk of bias (RoB), using the RoB tool, version 2 (RoB 2), of the five include studies, by domain and conclusive judgement.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root ca ies prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness the following four methods in preventing new root surface caries:

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Great Britain Sweden China Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW 6 of 14

Risk of Bias
The five included RCT studies were assessed using the RoB 2 tool [31]. Four out of five studies were conclusively deemed to have moderate RoB; the fifth study had high RoB (Table 2). Only the results from the studies with a moderate RoB were further analyzed. The characteristics of these four included studies are summarized in Table 3.  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months; (2) OHIs and applications of Cervitec varnish every 3 months; J. Clin. Med. 2023, 12, x FOR PEER REVIEW

Risk of Bias
The five included RCT studies were assessed u five studies were conclusively deemed to have mod RoB (Table 2). Only the results from the studies with lyzed. The characteristics of these four included stud  Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domicilia sional oral care for pendent elderly in homes-oral hygie bleeding, root carie ing staff's oral hea knowledge and att Aim To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the eff ing home residents sional cleaning, an OHIs provided by dental hygienists, son with daily oral usual.

Risk of Bias
The five included RCT studies were five studies were conclusively deemed t RoB (Table 2). Only the results from the lyzed. The characteristics of these four inc  To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.

Risk of Bias
The five included RCT s five studies were conclusively RoB (Table 2). Only the result lyzed. The characteristics of th

Title
Efficacy of regular professional brushing by a dental nurse for 3 months in nursing home residents-a randomized, controlled clinical trial.
The effects of the combination of chlorhexidine/thymol-and fluoride-containing varnishes on the severity of RCLs in frail institutionalized elderly people.
Effects of domiciliary professional oral care for care-dependent elderly in nursing homes-oral hygiene, gingival bleeding, root caries and nursing staff's oral health knowledge and attitudes.
A randomized trial on root caries prevention in elders.

Aim
To investigate the impact of professional brushing, performed every 2 weeks by a dental nurse, on the number of teeth, incidence of root caries, and further short-term oral health parameters, compared with residents whose oral hygiene was performed or supervised by staff according to standards of care corresponding to German law concerning the care for the elderly.
To determine the effect of a fluoride-containing varnish (Fluor protector) in combination with either Cervitec or a placebo varnish on the clinical characteristics of existing RCLs.
To describe the effects, for nursing home residents, of professional cleaning, and individual OHIs provided by registered dental hygienists, in comparison with daily oral care as usual.
To compare the effectiveness of the following four methods in preventing new root surface caries: (1) only OHIs every 3 months;

Interventions
All four included studies [52][53][54][55] were RCTs studying the effect of various interventions for prevention and/or arrest of RCLs in care-dependent older adults. The study subjects were followed for different length study periods, from 3 months to 3 years. The interventions were: (1) professional tooth brushing every second week; (2) fluor protector varnish (Cervitec ® ) application at baseline and at 6, 13, 26, and 39 weeks; (3) professional cleaning with sodium fluoride varnish (Duraphat ® ), application, and oral hygiene instruction (OHI) once a month; and (4) OHI in combination with Cervitec or Duraphat application every 3 months, or application of silver diamine fluoride (SDF) every 12 months (Table 3).

Analysis
The four studies included in this systematic literature review all had different outcomes and different study population sizes, and further differed in the interventions administered, in data measurements, and study duration. Therefore, owing to the heterogenicity of the included studies, no meta-analysis or SWiM was performed. The findings for each study are therefore presented separately and in a narrative manner.

Root Caries Index
Barbe et al. [52] and Tan et al. [55] used the DMFT index and the five-level RCI, respectively. In addition, Tan et al. [55] also used the DFS root score. Girestam Croonquist et al. [54] used Fejerskov et al.'s five-level RCI [28], while Brailsford et al. [53] measured the length/distance from the gingival margin, the height, and width of the RCLs (Table 3).
Girestam Croonquist et al. [54] used Fejerskov et al.'s five-level RCI for grouping root caries scores, namely: score 1-healthy root surface and/or no RCLs; scores 2 and 4-inactive initial and manifest RCLs; scores 3 and 5-active initial and manifest RCLs. For no RCLs and initial RCLs, improvements were seen for both groups throughout the study period. Between 3 and 6 months, improvement of active RCLs was reported for the intervention group (p = 0.05) ( Table 4).
Brailsford et al. [53] detected no new RCLs from baseline to 52 weeks in either group and concluded that RCLs in both groups were unchanged or had improved (Table 4). Contrarily, regarding height and width, the RCLs in the control group had increased compared with the intervention group (p < 0.001).
Tan et al. [55] followed their study subjects for 3 years. After 3 years, the group with only OHIs had a higher mean number of root surfaces with new active root caries or fillings compared with those with OHIs in combination with Cervitec or Duraphat or SDF application ( Table 4). The relative risk for developing new RCLs was lower in the intervention groups compared with the controls. Furthermore, no difference in prevention of new RCLs was found between applying chlorhexidine (CHX) (four times per year), sodium fluoride (four times per year), and 38% SDF annually for a 3-year period. Compared with only OHIs, the application groups had a lower risk of developing new RCLs. Also, groups with higher risk of developing root caries were detected among the study subjects. The groups with higher risk of developing root caries were denture users (denture type not specified, probably partial dentures or dentures in only one jaw) (p = 0.021), study subjects with higher visible plaque index (VPI) score and higher root caries experience at baseline (p = 0.001), and exposed root surfaces (p = 0.001).

Discussion
This systematic review aimed to investigate the effect of domiciliary professional oral care interventions on root caries development and progression, in comparison with self-performed or nurse-assisted oral care.
The four included studies investigated different intervention methods over a variety of intervals and study periods. However, all the studies showed a positive effect in reducing or arresting RCLs [52][53][54][55]. The parameters shared by all the studied interventions were participation of dental personnel in mechanical plaque removal combined with application of fluoride agents (varnish or toothpaste) or CHX. This combination may be beneficial for care-dependent older adults with risk of RCLs development and progression. The effectiveness of an intervention with fluoride varnish and topical agents for reduction of RCLs depends on the interval and the frequency of application. For example, sodium fluoride varnish (Duraphat) is recommended to be applied four times per year [11,12]; however, a frequency of twice a year has also been shown to be effective in reducing the number of RCLs in care-dependent older adults [50]. Tan et al. [55] performed an intervention using SDF only once a year; even at this relatively low rate of application, they were able to report greater effectiveness in reducing new RCLs incidence compared with the other substances (Duraphat or Cervitec) [55].
The successful use of SDF among children for preventing coronal caries [23] has led to increased interest in studies among the older population with annual application of 38% SDF [20,23,55]. Despite promising results for arresting RCLs, SDF is only approved for use in some countries [56]. After application, SDF leaves a dark discoloration of the caries lesions [57].

Active Participation of Dental Personnel
Professional dental hygiene interventions have shown advantageous effects on oral hygiene status and management of RCLs within a relatively short time interval such as 2 weeks [52] or 1 month [54]. Regular and effective oral hygiene routines are important for care-dependent older adults. In addition, despite the costs of the intervention, a visit by a dental nurse could serve as a reminder for oral self-care. Hesitation to spend more for oral hygiene services was observed among the study subjects and their relatives in Barbe et al. [52], who report that participation would have been compromised if it had not been free of charge.

Training Nursing Staff
Education and hands-on training for both care-dependent older adults and nursing staff could contribute to improving oral hygiene among those in need [17]. Nurse-assisted oral care, particularly oral hygiene, is tedious and requires meticulous attention [16,49,58], particularly in view of the higher tendency of older people to retain their own teeth in high ages, and in view of complex dental constructions [21]. Moreover, nurse-assisted oral care for nursing home residents with poor cognitive function and communication problems is challenging [22]. Therefore, training in oral health care skills may be more useful than theoretical education for health care personnel [59,60]. To our knowledge, improved oral hygiene and compliance to perform such oral care routines over time has not been noted. One possible reason could be the high turnover rate among nursing staff in care of care-dependent older adults [61].

Awareness and Information among the Older Adults
There is a lack of prioritization of oral health, both among care-dependent older adults and among the nursing staff [62]. This could be attributed to insufficient knowledge of the connection between poor oral health and systemic diseases [2]. It is an important task for the dental profession to provide this knowledge before or in the early stages of care dependency. Failing to do so could lead to problems and high costs for health and dental care at both individual and societal levels [21].
Even though we had fairly open inclusion criteria, it was hard to identify studies that matched these. We found great diversity in study design, choice of intervention, and reported outcomes in the included four studies. When outcomes and outcome measurements differ, making it impossible to perform a meta-analysis, it may not be possible to improve future patient care. For future studies in this field, one possible way of using similar outcome measurements is, for example, to use the Core Outcome Measures in Effectiveness Trials (COMET) database to improve the efficiency of clinical trials and outcome measures. This database can be used to develop core outcome sets (COSs) [63]. COSs allow us to compare and collate results from various studies so that the basis for decisions, for both patients and dentalcare personnel, could be strengthened. Additionally, international consensus on appropriate interventions and outcome measurements would increase the feasibility of performing a meta-analysis of selected RCT studies involving clinical management of RCLs in frail older adults. A meta-analysis is crucial for closing the knowledge gap and conducting a clinical protocol for managing RCLs in frail older adults.

Conclusions
Based on the available literature it is not possible to conclusively determine the effect of domiciliary professional oral care on root caries development and progression in caredependent older adults. Future studies in this field should use a standardized protocol for RCT studies with similar study design, interventions, outcomes, and follow-up periods to enable comparison and meta-analysis.

Clinical Relevance
There is a need to investigate the current scientific knowledge of the effect of domiciliary professional oral care interventions to prevent and arrest progression of RCLs. A great proportion of care-dependent older adults are prone to this condition, which calls for identification of evidence-based strategies to address the issue among this population.
This review highlights the importance of dental personnel and optimal mechanical plaque removal with fluoride or CHX application in impeding or arresting RCLs. Adequate timely information and awareness about the risk of RCLs, prevention, and management methods are therefore crucial, ideally before the person enters the phase of care dependency.

Supporting Information
Contact was made with the author Anna-Grete Barbe regarding the number of participants included in her and her co-authors' study. The right number was 50 (25 in each group). They recruited one more person after randomization.

Difference between Protocol and Review
Root caries development and progression on buccal root surface were initially the primary outcome measures. This was changed to root caries development and progression measured by a caries index.