Role of the Lund–Mackay Score in Determining Surgical Indication in Odontogenic Chronic Rhinosinusitis

Abstract

Computed tomography (CT) of the paranasal sinuses is essential in diagnosing odontogenic chronic rhinosinusitis. Treatment primarily targets the dental focus, with endoscopic sinus surgery (ESS) indicated when necessary. Assessing CT findings using the Lund–Mackay score (LMS) may guide therapeutic decisions. This study retrospectively compared LMS, dental pathology type, and reported symptoms with treatment choices in patients treated for odontogenic chronic rhinosinusitis between 2012 and 2022 at a tertiary otorhinolaryngology center. Of 2067 chronic rhinosinusitis patients, 61 had an odontogenic cause. LMS was determined in 57 patients and correlated with treatment strategy. Dental pathology subtypes and presenting symptoms were also analyzed. A control group of 25 patients with localized, non-odontogenic chronic rhinosinusitis was included. Fifteen patients not undergoing ESS had lower LMS values (median one), while 42 surgical patients had higher scores (median six). Periapical pathology (47.4%) and oroantral fistula (26.3%) were the most common causes. Nasal discharge and pain were the most frequent symptoms. Neither dental pathology type nor symptoms significantly influenced treatment decisions. The extent of CT-detected pathology, reflected by LMS, can serve as a key criterion in determining treatment for odontogenic chronic rhinosinusitis, independent of symptoms or specific dental pathology type.

1. Introduction

Odontogenic chronic rhinosinusitis (OCRS) is a subtype of chronic rhinosinusitis (CRS) associated with dental infection. The definition corresponds to CRS, with OCRS additionally requiring an identifiable odontogenic cause. According to EPOS 2020, OCRS belongs to the category of secondary localized (usually unilateral) forms of CRS [1]. Older literature reports OCRS prevalence in CRS at 10–15%, whereas more recent studies report up to 40% [2,3,4,5]. This trend is attributed to the increasing number of procedures in conservative oral surgery and dental implantology [3,5,6]. Recent consensus statements also emphasize that OCRS remains underdiagnosed worldwide, largely due to missed dental findings on imaging and insufficient interdisciplinary collaboration [7,8,9].

The key etiopathogenetic requirement for OCRS is disruption of the Schneiderian membrane lining the maxillary sinus. Due to its close proximity to the roots of upper premolars and molars, inflammatory processes may spread into the maxillary sinus and subsequently into other paranasal sinuses [10,11,12]. Causes include periapical pathology (chronic periodontitis, periapical abscess, radicular cyst), oroantral fistula (persistent oroantral communication after tooth extraction), inflammatory complications after implant placement, or complications of endodontic treatment (e.g., overfilling of root canals) [13,14,15,16,17]. All these complications share a common origin: carious or periodontally compromised teeth resulting from inadequate oral hygiene. Less common causes include trauma and retained, ectopic, or supernumerary teeth [18,19,20].

The microbiology of OCRS differs from non-odontogenic CRS. Strict and facultative anaerobes are more frequent, often presenting as mixed aerobic–anaerobic infections. Common pathogens include Peptostreptococcus spp., Prevotella spp., Fusobacterium spp., and Eikinella corrodens [21,22,23]. Other organisms include alpha-hemolytic streptococci, Staphylococcus aureus, and Pseudomonas aeruginosa [2,24]. Fungal species such as Candida albicans or Aspergillus spp. may also occur, particularly in cases of overfilled root canals leading to fungus balls of odontogenic origin [3,25,26]. Recent microbiome studies demonstrate pronounced dysbiosis with enrichment of obligate anaerobes in OCRS, further distinguishing it from non-odontogenic CRS and supporting its classification as a distinct entity [23].

Typical symptoms include nasal discharge (usually unilateral, anterior or postnasal, often malodorous), facial or dental pain/pressure, nasal obstruction, and olfactory dysfunction [3,27]. Less common symptoms are cough, nausea, fatigue, fever, or fetor [2,4]. Symptoms must persist for more than 12 weeks to meet CRS criteria.

Diagnosis is multidisciplinary, combining history, clinical examination by both dentist and ENT specialist, including nasal endoscopy, and imaging studies [28]. Conventional CT of the paranasal sinuses is the standard modality, confirming the dental cause and displaying the extent of sinus involvement. Disease severity may be classified using the Lund–Mackay (LMS) or modified Zinreich score [29,30,31]. Additional imaging options include panoramic radiography (OPG) or cone-beam CT (CBCT) [6]. International diagnostic guidelines increasingly stress the need for standardized radiologic assessment, clear dental–sinonasal correlation, and consensus-based criteria to reduce misdiagnosis and improve interdisciplinary communication [7].

Treatment of OCRS consists of eliminating the underlying dental source (tooth removal, implant removal, closure of oroantral fistula, etc.) and managing the affected paranasal sinuses, typically using ESS (usually middle meatal antrostomy, with further steps depending on disease extent) [32]. Dental treatment should ideally precede ESS or be performed during the same session. Dental management alone may resolve symptoms, with ESS reserved for persistent disease [3,33]. Conservative therapy using antibiotics or nasal corticosteroids is usually ineffective but may temporarily alleviate symptoms (e.g., preoperatively) [34]. Current expert consensus emphasizes tailored multimodal management, with coordinated dental–ENT decision pathways and a strong recommendation for simultaneous treatment in selected cases—particularly those with OAF or multisinus involvement [8,9].

2. Materials and Methods

A total of 2067 patients with CRS examined between 2012 and 2022 were identified. Among them, 86 had unilateral localized CRS. Based on history, clinical examinations (ENT and dental), and CT findings, 61 patients were diagnosed with OCRS. Four patients were excluded due to incomplete CT documentation, leaving 57 for final analysis. The remaining 25 patients with unilateral CRS of non-odontogenic origin formed the control group.

In the OCRS cohort (n = 57, mean age 50.05 ± 15.50 years; 27 men, 30 women), CRS symptoms, dental pathology subtype, and LMS (calculated for the affected side only) were evaluated. Patients treated solely by dental intervention were compared with those treated surgically with FESS (with or without simultaneous dental surgery). In surgically treated patients, the proportion undergoing combined FESS and dental surgery and the specific teeth treated were recorded.

In the control group (n = 25, mean age 48.12 ± 19.12 years; 9 men, 16 women), LMS values were similarly assessed in operated and conservatively treated patients separately and compared with the OCRS group. Conservative treatment consisted of topical corticosteroids and saline irrigation.

Statistical analyses included the Mann–Whitney U test, Student’s t-test, chi-square test, and biserial correlation.

3. Results

During the study period, 61 patients with OCRS were treated, representing 3.0% of all CRS cases. Among unilateral CRS cases, OCRS accounted for 69.5%.

Of the 57 evaluated OCRS patients, 15 (26.3%) were treated exclusively by dental intervention, while 42 (73.7%) underwent ESS. All procedures were endoscopic; one case required a supplementary Caldwell–Luc approach. In 21 patients (50% of the surgical group), dental surgery (e.g., extraction, closure of chronic or acute oroantral fistula using a Wassmund flap) was performed in one procedure. The most frequently extracted teeth were the first molar (nine cases), second molar (seven cases), and second premolar (five cases).

LMS on the affected side ranged from 1 to 11 in patients undergoing ESS (median six). In contrast, LMS in patients not undergoing surgery ranged from zero to four (median one) and the difference was significant (p < 0.001). (Figure 1 and Figure 2). In this perspective, the LMS cut-off value for the use of ESS can be proposed to be five.

In the control group, 18 of 25 patients (72.0%) underwent FESS; three procedures included concomitant septoplasty to optimize surgical access. LMS values for surgically treated patients ranged from 1 to 10 (median 3.5). Conservatively treated patients had LMS values between one and seven (median two). The difference between the control and study groups was not significant in this respect.

The most frequently reported symptom was nasal discharge (46 patients, 80.7%), usually unilateral and malodorous. Facial pressure/pain occurred in 35 patients (61.4%), nasal obstruction in 21 (36.8%), olfactory dysfunction in 3 (6%), and facial swelling in 2 (4%). Nasal discharge correlated positively with increasing LMS (p = 0.043), whereas nasal obstruction (p = 0.265) and pain (p = 0.712) did not. No significant relationship was found between treatment modality and symptoms.

The most common etiologies were periapical pathology (27 patients, 47.4%), oroantral fistula (15 patients, 26.3%), endodontic complications (7 patients, 12.3%), implant-related inflammation (5 patients, 8.8%), and retained tooth (3 patients, 5.3%).

4. Discussion

During the study period, OCRS accounted for 3.0% of all CRS cases—lower than values reported in the literature [2,3,4,5]. This may reflect a higher proportion of diffuse nasal polyposis cases at the tertiary care center. Within unilateral CRS, the proportion of OCRS (69.5%) corresponded well with published data [2,27]. Age distribution and sex ratio also matched literature reports [2,31]. Similar proportions have been reported in recent consensus publications, which continue to highlight OCRS as a frequently overlooked but clinically relevant CRS subtype [7].

The primary finding was a statistically significant difference in LMS values between OCRS patients treated with FESS and those managed dentally only. Patients undergoing ESS had significantly higher LMS (p < 0.001). This is in agreement with current expert recommendations, which advise that extensive disease—particularly with ostiomeatal involvement or multisinus extension—warrants ESS in combination with dental therapy [8,9] (Figure 3).

The ostiomeatal complex appears to be a key factor: involvement of the maxillary sinus together with the ostiomeatal unit (and possibly other sinuses) suggests preference for ESS with simultaneous dental management [31]. This aligns with newer treatment frameworks proposing algorithmic, staged, or combined approaches based on anatomical obstruction patterns and dental pathology severity [8]. Prospective studies would be useful to validate whether selected patients with higher LMS may still be successfully treated with dental therapy alone. Some authors support an initial dental-only approach [2], while others advocate primary ESS [33]. However, cases involving OAF frequently require simultaneous surgical management, as persistent fistulae maintain sinonasal contamination and impair sinus ventilation [20].

Symptoms in our study—mainly nasal discharge and pain—reflect published patterns. Only nasal discharge correlated with LMS. No previous studies have evaluated symptom–LMS correlation specifically in OCRS. Future work could use visual analog scales (VAS) for symptom severity. Recent consensus documents emphasize developing standardized symptom-based assessment tools specific to OCRS to better correlate clinical presentation with radiologic and microbiological findings [7,9].

The distribution of odontogenic causes was consistent with the literature, though classification methods vary across studies. No significant relationship between the type of dental pathology and treatment choice was observed. Nevertheless, expert groups recommend unified terminology and cause classification—particularly distinguishing OAF-related disease, implant-associated pathology, and endodontic complications—to improve comparability across studies [8].

The control group of patients with localized chronic rhinosinusitis of non-odontogenic etiology did not exhibit overall differences in LMS values compared with the OCRS group. Thus, the distribution of LMSs was similar between the groups (p = 0.258). Within the control group itself, LMS values did not differ between surgically and nonsurgically treated patients (p = 0.412). While non-operated OCRS patients were referred for dental treatment, conservative management in the control group consisted of antibiotics, topical corticosteroids and saline irrigations. This observation is compatible with recent data showing that radiologic extent in localized CRS does not always dictate treatment approach, whereas in OCRS, the presence of odontogenic drivers and ostiomeatal obstruction are more decisive determinants [7,9].

5. Conclusions

To date, LMS has not been described as a criterion for treatment selection in OCRS. Based on our findings, LMS may help guide decision-making. CT findings appear more important than specific symptoms or dental pathology type. Involvement of the ostiomeatal complex seems crucial. When maxillary sinus disease does not extend to the ostium, dental treatment alone may be sufficient (Figure 4).

When inflammation extends beyond the ostiomeatal unit into ethmoids or additional sinuses, primary FESS combined with dental surgery is likely more appropriate. The presented study also has its limitations. One limitation is the relatively small number of patients included. Further, especially prospective, randomized studies are needed in the future to confirm these results.