1. Introduction
Periodontitis is the component of periodontal disease [
1] associated with inflammation of the periodontium resulting in progressive bone and soft tissue destruction, ultimately leading to tooth loss [
2]. The etiology of periodontitis originates with the development of a bacterial biofilm, or plaque, on the tooth surface and oral epithelia [
2,
3]. The host response to the pathogenic biofilm is to initiate periodontal inflammation and recruit polymorphonuclear neutrophils (PMNs) to the infection site [
2,
3]. PMNs respond to the microbial threats via the creation of reactive oxygen species (ROS), which in chronic inflammation, results in a state of oxidative stress [
4].
Dietary supplement use may modify the risk for the development and progression of periodontal disease [
5,
6,
7,
8,
9]. The antioxidant activity [
4] of nutrients such as vitamin C [
10,
11], and α-tocopherol [
12], and the anti-inflammatory activity [
7] of polyunsaturated fatty acids (docosahexaeonic acid (DHA) [
13,
14]) may attenuate the development of periodontal disease. Studies using the NHANES III-a large cross-sectional survey study-have demonstrated that lower vitamin C intake is associated with a higher risk (OR 1.19) of having periodontal disease [
10], and that higher vitamin C intake is associated with a reduced risk (OR 0.53) of severe periodontitis [
11]. Additionally, using data from the NHANES III, the highest quintile of serum total antioxidant activity (TAOC) was associated with reduced risk (OR 0.63) of severe periodontitis [
11]. Association studies have also shown that low intakes of α-tocopherol or DHA are associated with an increased risk of periodontal disease [
12,
13,
14]. Large cross-sectional survey studies have identified that periodontal disease affects a substantial number of individuals and given the potential systemic health effects linked to periodontal disease (
i.e., cardiovascular disease and preterm birth), periodontal disease represents a pubic health concern [
3]. The Canadian Health Measures Survey from 2007 to 2009 reports that 21% of Canadian adults with natural teeth have experienced a moderate to severe periodontal problem [
15], and current estimates from the United States (2009–2010 NHANES) report that periodontitis affects 47% of the adult population over 30 years of age [
16]. At present, it is unclear exactly how much of the periodontal disease burden may be exacerbated by poor nutrition. Furthermore, there is limited data regarding whether dietary interventions may enhance recovery from periodontal disease.
Physical disruption of the microbial biofilm at hygiene appointments is the first-line intervention toward periodontal disease [
2]. However, emerging data from dietary intervention studies suggest a functional role for diet or dietary supplements in supporting periodontal health and attenuating periodontal disease [
17,
18,
19]. For instance, a diet focusing on whole fresh foods—fruits, vegetables and whole-grains—while limiting processed foods, reduced periodontal inflammation in 20 women with metabolic syndrome [
17]. Dietary intervention of two grapefruits per day for two weeks was associated with lower sulcus bleeding in patients with chronic periodontitis [
18]. A diet rich in whole-grains has also been shown to reduce the risk of periodontitis by 23% in a prospective study of male health professionals [
19]. Moreover, dietary supplements have been shown to have beneficial effects. Supplementation with a fruit and vegetable concentrate in capsules resulted in improvements in probing depth, bleeding on probing, and plaque scores [
20]. Another supplementation study, using borage oil that contains high levels of omega-6, improved both probing depth and gingival inflammation in adults with periodontitis [
21]. Supplementation with lycopene, in combination with oral prophylaxis, has also been shown to attenuate gingival inflammation more effectively than oral prophylaxis alone [
22]. Together, the studies discussed highlight the potential importance of diet or dietary supplements in reducing periodontal inflammation in combination with regular hygiene maintenance.
In addition to maintenance of periodontal health, a few studies have shown that diet may assist with wound healing from periodontal procedures. These few studies have shown that micronutrients (vitamin D and the B vitamins) [
23,
24,
25] and macronutrients (DHA and eicosapentaenoic acid (EPA)) [
26,
27] can improve patient recovery following periodontal therapy. Being vitamin D sufficient (serum 25(OH)D > 50 nmol/L) before open flap debridement surgery resulted in greater clinical attachment levels and reductions in probing depths post-surgery than patients with lower levels of serum 25(OH)D [
23]. Likewise, patients receiving access flap surgery experienced better clinical attachment levels when treated post-operatively with a vitamin-B complex (50 mg thiamine HCl, riboflavin, niacinamide,
d-calcium pantothenate, pyridoxine HCl; 50 μg
d-biotin, cyanocobalamin; 400 μg folate) [
24]. Vitamin B12 as a component of post-surgical medication also resulted in less patient pain at 6 and 120 h post third molar extraction than in control patients [
25]. In patients requiring sanative therapy, a combination of acetylsalicylic acid (81 mg) and fish oil (containing 900 mg DHA and EPA) decreased probing depths while increasing clinical attachment and reducing levels of salivary RANKL and MMP-8, markers of inflammation [
26]. Similarly, in patients with a furcation defect requiring bone allograft, a combination therapy of acetylsalicylic acid (75 mg) and DHA (900 mg) and EPA (450 mg) resulted in greater clinical attachment, probing depth reductions, and decreased amounts of IL-1β present in the gingival crevicular fluid [
27].
Together, findings from these studies suggest that use of dietary supplements during and after periodontal procedures may improve periodontal health outcomes following periodontal procedures. However, randomized controlled trials are needed to more definitively determine how dietary supplements may enhance outcomes after periodontal procedures. The objective of this study was to characterize the use of dietary supplements by patients who attend a periodontal clinic for one of three reasons: comprehensive general examination, implant consultation or other surgical consultation. By understanding the pattern of intakes, researchers will be better informed to design intervention studies that will support better long-term outcomes after periodontal procedures.
4. Discussion
This study showed that females used more supplements than males, and that general supplement use increased with subject age, regardless of sex. Moreover, smokers used fewer supplements than non-smokers. Interestingly, the list of the 10 most commonly used dietary supplements was relatively similar when comparing by sex, age, smoking status or reason for visit.
The finding that females used more supplements than males, and that supplement use increased with subject age, was not surprising based on data from the Canadian Community Health Survey (2004–2005). The Canadian Community Health Survey (CCHS) cycle 2.2 is a nationwide cross-sectional nutrition survey representing 98% of all province-dwelling Canadians (
n = 35,107). The CCHS cycle 2.2 had a response rate of 76.5% and as part of its design included an assessment of the nutritional supplements used by each participant [
28]. According to the CCHS 2.2, total supplement use by Canadians was 40.1% [
29] and multivitamin use, defined as ≥ three supplements, was 28% [
30]. Total supplement use in the present study was 64.1%, much greater than the CCHS but may be explained by the fact that patients visiting the periodontal clinic had a higher proportion of older individuals in which supplement use is higher. Another reason for the difference may be the fact that we used a detailed list of supplements whereas the CCHS focused on multivitamin use without consideration of herbals or botanicals [
28]. Similar to our findings, Shakur
et al., 2012 reported greater supplement use between the NHANES survey and the CCHS 2.2, with the difference being attributed to the fact that NHANES examines a greater variety of supplements (such as herbals or botanicals) than the CCHS 2.2 [
30]. The fact that our survey contained a wide variety of possible nutritional supplements, not limited to vitamins and minerals, may explain our greater percentage of total supplement use compared to the CCHS 2.2. However, good agreement between the studies was observed for individual supplement use such as multivitamin (28.0%
vs. 31.1%), vitamin D (28.0%
vs. 31.1%), and calcium (28.0%
vs. 25.8%), in which the first percentage is from the CCHS 2.2 [
30]. Additionally, the CCHS 2.2 and NHANES (2003–2006) studies, similar to the findings of the present study, reported greater supplement use among women compared to men, and greater supplement use with older age [
29,
30,
31] .
Given the challenge of attaining the dietary reference intake for calcium and vitamin D from diet alone in the Canadian elderly [
32,
33,
34,
35,
36] and public health messages encouraging use of vitamin D supplements, it was not surprising that calcium and vitamin D supplement use increased in the post-50 age categories. As part of the Canada’s Food Guide, Health Canada advises that all Canadians 50 years or older consume a vitamin D supplement containing 400 IU per day [
37]. Moreover, other organizations such as the Canadian Cancer Society suggest Canadians consume a vitamin D supplement containing 1000 IU in the winter months [
38]. In addition to calcium and vitamin D, multivitamin and vitamin C supplement use were also included in the four most used supplements after age 50 years. This is supported by a survey of Canadian community-living older adults in which calcium, vitamin C and D were frequently used micronutrients and overall multivitamin use was high (43.5%) [
35]. In a study of Ontario seniors living in long term care facilities, supplementation with the recommended vitamin D dose (>400 IU/day) was effective in ensuring that >90% of the seniors achieved optimum serum 25(OH)D levels (>75 nmol/L) [
36].
Vitamin C is critical for the maintenance of periodontal health. It is well known that smoking depletes vitamin C stores and thus smokers should consume a vitamin C supplement or increase their dietary intake of vitamin C [
39]. However, use of vitamin C supplements was not higher among smokers in this study. This finding is similar to findings from the CCHS 2.2 that reported no difference in vitamin C supplement use between smokers and non-smokers [
39]. Whether supplementation with vitamin C improves wound healing after periodontal surgery in smokers requires investigation. Our study also showed that current smokers used less calcium, vitamin D, green tea and fish oil supplements. The effect of these supplements in smokers
versus non-smokers at improving wound healing after periodontal procedures is an area for future investigation.
Supplement use was largely similar among patients regardless of their reason for visit. The only difference was that patients receiving a surgical consultation had lower usage frequency of glucosamine than patients receiving comprehensive general examination or implant consultation. There is no clear link between glucosamine supplement use and the different reasons for visiting the periodontist. However, males and those over 70 years of age did report glucosamine as one of the most commonly used supplements and may have been more represented in the comprehensive general examination or implant consultation groups.