Poor Oral Health as a Risk Factor for Dementia in a Swedish Population: A Cohort Study with 40 Years of Follow-Up.

BACKGROUND: Whether poor oral health is associated with dementia risk remains unclear. OBJECTIVE: We conducted a cohort study of 14,439 participants who were followed up for up to 40 years in Uppsala County, central Sweden, aiming to explore the association between poor oral health, namely the number of tooth loss, dental plaque status, and oral mucosal lesions, and the risk of dementia. METHODS: We used Cox proportional hazards regression model to derive cause-specific hazard ratios (HR) and corresponding 95% confidence intervals (CI), while adjusting for baseline potential confounders as well as a time-varying covariate, Charlson's Comorbidity Index score. RESULTS: Dementia risk was substantially higher among those with a higher number of tooth loss; compared to the group with tooth loss 0-10, the HRs were 1.21 (95% CI: 1.02, 1.42), 1.17 (95% CI: 0.97, 1.40), and 1.30 (95% CI: 1.09, 1.54) respectively for groups with increasing number of tooth loss. There was some evidence of dose-risk association in this study, with a HR of 1.10 (1.04, 1.18) comparing adjacent groups (ptrend = 0.001). In a stratified analysis by attained age, tooth loss was more pronouncedly associated with the risk of dementia onset before age 80 (those with 21-32 versus 0-10 lost teeth, HR = 1.82, (95% CI: 1.32, 2.51); HR = 1.22 (95% CI: 1.10, 1.35) comparing adjacent groups, ptrend < 0.001). CONCLUSION: In summary, there are some indications that poor oral health, as indicated by more tooth loss, is positively associated with an increased risk of dementia, especially for dementia onset before age 80.

Poor oral health and risk of incident myocardial infarction: A prospective cohort study of Swedish adults, 1973-2012.

Previous studies provide conflicting evidence as to whether there is an association between poor oral health and an increased risk of myocardial infarction. The aim of the study was to deepen knowledge of the association between oral health and myocardial infarction risk using a large (n = 20,133), prospective, and population-based cohort in Uppsala, Sweden. Oral health was determined during a clinical dental examination at entry into the cohort in 1973/74. Individuals were followed through linkage with the Swedish National Patient Register, Cause of Death Register and Emigration Register. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) for total, non-fatal and fatal myocardial infarction events. Increased risks of total, non-fatal and fatal myocardial infarction events among individuals with fewer reference teeth at examination, more dental plaque and a borderline significant increased risk among individuals with oral lesions were observed. Adjustment for multiple potential confounding factors did not change the results appreciably. However, the observed HRs generally decreased towards one when the analysis was confined to non-tobacco users only. The results from this study indicate that poor oral health is associated with a slightly increased risk of myocardial infarction; however, these results may be partly explained by residual confounding.

Association between poor oral health and gastric cancer: A prospective cohort study.

Poor oral health may be involved in the pathogenesis of gastric cancer, however, some aspects have not been explored. Further, for previously studied aspects, for example, tooth-loss, the findings are inconsistent. We conducted a prospective cohort study of 19,831 participants from Uppsala, Sweden, cancer-free at baseline in 1973-1974 and followed until 2012 through linkage to national registers. We found that individuals with fewest teeth at baseline had an increased risk of gastric cancer relative to subjects with all examined teeth present (p = 1.75e-2). Presence of denture-associated lesions was also associated with an increased risk of gastric cancer (p = 1.00e-4). However, these excess risks significantly varied with attained age; estimated hazard ratio (HR) at attained age 50 for tooth loss was 4.24 [95% confidence interval (CI) 1.83-9.80] and 5.91 (95% CI 2.76-12.63) for denture-associated lesions, decreasing at an estimated 4% and 6% per year respectively, resulting in HR of 1.54 (95% CI 0.90-2.64) for tooth loss and HR 1.29 (95% CI 0.90-1.85) for denture-associated lesions at attained age 75. No increased risk of gastric cancer was found for individuals with higher levels of dental plaque, or with Candida-related or tongue lesions. In conclusion, tooth-loss and denture-associated lesions are associated with increased risks of gastric cancer. Previous conflicting findings of tooth-loss and gastric cancer risk may partly be explained by the age-varying relative risk of gastric cancer.

Tobacco Use, Oral Health, and Risk of Parkinson's Disease.

Few studies have investigated the associations between use of Swedish moist snuff (snus), associated poor oral health, and risk of Parkinson's disease (PD). We followed 20,175 participants who were free of PD in 1973-1974 in Uppsala, Sweden, until the end of 2012. We used Cox proportional hazards regression models to estimate hazard ratios and corresponding 95% confidence intervals for the associations between tobacco use, oral health indicators, and PD risk. We found that tobacco use was associated with a lower risk of PD in males. Compared with males who never used any tobacco daily, pure ever tobacco smokers, pure ever snus users, and combined users had adjusted hazard ratios of 0.68 (95% confidence interval (CI): 0.49, 0.93; n = 83), 0.51 (95% CI: 0.27, 0.95; n = 11), and 0.21 (95% CI: 0.07, 0.67; n = 3), respectively. No association was observed for number of teeth, dental plaque, or detectable oral mucosal lesions and PD risk, although there was a suggestive association with Candida-related oral mucosal lesions in males (hazard ratio = 1.56, 95% CI: 0.92, 2.65; P = 0.098). Use of snus is associated with a lower risk of PD in males, while poor oral health seems not to be associated with PD occurrence.

Inverse Association Between Poor Oral Health and Inflammatory Bowel Diseases.

BACKGROUND & AIMS: The hygiene hypothesis (a lack of childhood exposure to microorganisms increases susceptibility to allergic diseases by altering immune development) has been proposed as an explanation for the increasing incidence of inflammatory bowel disease (IBD). However, there are few data on the relationship between oral hygiene and development of IBD, and study results have been inconsistent. We investigated the association between poor oral health and risks of IBD, ulcerative colitis (UC), and Crohn's disease (CD). METHODS: We performed a population-based cohort study of 20,162 individuals followed for 40 years (from 1973 to 2012). Residents of 2 municipalities of Uppsala County, Sweden (N = 30,118), 15 years or older, were invited, and among them 20,333 were examined for tooth loss, dental plaques, and oral mucosal lesions at the time of study entry. Other exposure data were collected from questionnaires. Patients who later developed IBD (UC or CD) were identified by international classification codes from Swedish National Patient and Cause of Death Registers. Cox proportional hazards regression was used to estimate hazard ratios for IBD, UC, and CD. RESULTS: From National Patient and Cause of Death Registers, we identified 209 individuals who developed IBD (142 developed UC and 67 developed CD), with an incidence rate of 37.3 per 100,000 person-years. We found an inverse relationship between poor oral health and IBD, especially in individuals with severe oral problems. Loss of 5-6 teeth of the 6 teeth examined was associated with a lower risk of IBD (hazard ratio, 0.56; 95% confidence interval, 0.32-0.98). Having dental plaques that covered more than 33% of tooth surface was negatively associated with CD (hazard ratio, 0.32; 95% confidence interval, 0.10-0.97). CONCLUSIONS: In a population-based cohort study of more than 20,000 people in Sweden, we associated poor oral health with reduced risk of future IBD.

A prospective cohort study on poor oral hygiene and pancreatic cancer risk.

Poor oral hygiene has been proposed to increase the risk for pancreatic cancer. We aim to assess this hypothesis, using number of teeth, dental plaque and oral mucosal lesions examined at baseline as a proxy for oral hygiene. During 1973-74 a population-based prevalence study of oral mucosal lesions was carried out in Uppsala County in central Sweden. We followed the study population through linkages with the Swedish Cancer and Total Population registers. A total of 19,924 participants were included, and 126 pancreatic cancer cases were identified during an average of 28.7 years of follow-up. Hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) for pancreatic cancer were estimated using Cox proportional hazards regression models. Overall, subjects with fewer teeth at baseline tended to have an increased risk for pancreatic cancer, although the estimates were not statistically significant. Among subjects with more than 10 teeth, those with unacceptable dental plaque had an HR of 2.1 (95% CI: 1.0, 4.7), compared with those without dental plaque after adjustment for potential confounding factors. Individuals with Candida-related or denture-related oral mucosal lesions, or tongue lesions, compared with those without any of the three studied lesions, had a 70, 30 and 80% excess risk of developing pancreatic cancer, respectively. Presence of more than one type of studied lesions further increased the risk for pancreatic cancer. In conclusion, our findings provide evidence to support the hypothesis that poor oral hygiene plays an important role in the development of pancreatic cancer.

Contact allergies to potential allergens in patients with oral lichen lesions.

OBJECTIVE: The aim of the present controlled study was to investigate a possible relationship between contact allergies to potential allergens and oral lichen lesions. METHODS: Eighty-three patients with oral lichen lesions (OLL) and control groups of age- and gender-matched dermatitis patients (DP, n = 83) and patch-tested dermatitis patients randomly selected from files (PSFF, n = 319) were included in the study. OLL and DP groups were patch-tested epicutaneously and examined intraorally. RESULTS: The frequencies of contact allergy to mercury and carvone were statistically higher in the OLL group than in the DP group. Surfaces of amalgam and composite restorations were statistically more frequent in the OLL group compared to the DP group. Contact allergy to nickel and colophony, the latter with a statistically significant difference, was more common in the DP group. The numerical difference found for nickel allergy was, however, not significant comparing the OLL and PSFF groups. CONCLUSION: Contact allergy to mercury was overrepresented in patients with OLL and has been reported in previous studies, but the present finding of an overrepresentation of contact allergy to carvone in patients with oral lichen lesions has not been reported previously. CLINICAL RELEVANCE: Carvone, in addition to mercury and gold, as previously suggested, can be one of the causative or maintenant factors for oral lichen lesions. Carvone-hypersensitive patients with oral lichen lesions should therefore avoid carvone-containing products for oral use.

The necessity of a test reading after 1 week to detect late positive patch test reactions in patients with oral lichen lesions.

OBJECTIVES: Establishing the clinical relevance of contact allergy to dental materials in patients with oral lichen lesions (OLL) may be difficult, and tests are often read only on day 3 or day 4; also, concentration of the tested allergens may vary. Several studies on dermatitis patients have shown that additional positive patch test reactions can be found after day 4. Therefore, the aim of the present study was to analyse the frequency of late positive reactions to potential allergens in patients with OLL. MATERIAL AND METHODS: Eighty-three of 96 consecutive patients with biopsy-verified OLL were patch-tested with a recently developed lichen series. The patches were removed after 48 h and reactions read 3 and 7 days after application. RESULTS: A total of 129 contact allergies were found, and 26 (20.2 %) of the allergic reactions in 23 patients were seen on day 7 only. The 25.2 % increase in positive test reactions with an additional reading on day 7 in addition to day 3 was statistically significant. Metals were the substances with the highest frequency of late positive reactions. CONCLUSIONS: Patients with OLL cannot be considered properly investigated with regard to contact allergy, unless the testing has been performed with mandatory readings on day 3 (or day 4) and day 7. CLINICAL RELEVANCE: Late patch test readings are crucial in order to elucidate the role of contact allergy to dental materials in the aetiology of OLL.

Factors affecting commencement and cessation of smoking behaviour in Malaysian adults.

BACKGROUND: Tobacco consumption peak in developed countries has passed, however, it is on the increase in many developing countries. Apart from cigarettes, consumption of local hand-rolled cigarettes such as bidi and rokok daun are prevalent in specific communities. Although factors associated with smoking initiation and cessation has been investigated elsewhere, the only available data for Malaysia is on prevalence. This study aims to investigate factors associated with smoking initiation and cessation which is imperative in designing intervention programs. METHODS: Data were collected from 11,697 adults by trained recording clerks on sociodemographic characteristics, practice of other risk habit and details of smoking such as type, duration and frequency. Smoking commencement and cessation were analyzed using the Kaplan-Meier estimates and log-rank tests. Univariate and multivariate Cox proportional hazard regression models were used to calculate the hazard rate ratios. RESULTS: Males had a much higher prevalence of the habit (61.7%) as compared to females (5.8%). Cessation was found to be most common among the Chinese and those regularly consuming alcoholic beverages. Kaplan-Meier plot shows that although males are more likely to start smoking, females are found to be less likely to stop. History of betel quid chewing and alcohol consumption significantly increase the likelihood of commencement (p < 0.0001), while cessation was least likely among Indians, current quid chewers and kretek users (p < 0.01). CONCLUSIONS: Gender, ethnicity, history of quid chewing and alcohol consumption have been found to be important factors in smoking commencement; while ethnicity, betel quid chewing and type of tobacco smoked influences cessation.

Contact allergy to gold in patients with oral lichen lesions.

The aetiology of oral lichen lesions is obscure. In this study the frequency of contact allergy to gold in 83 patients with oral lichen lesions was compared with that in two control groups, comprising 319 age- and gender-matched patients with dermatitis selected from files and 83 clinically examined dermatitis patients. All patients were tested epicutaneously with gold sodium thiosulphate. The two control groups tested were under examination for a tentative diagnosis of allergic dermatitis not related to oral problems. The frequency of contact allergy to gold was 28.9% in the patients with oral lichen lesions, 18.2% in patients selected from files, and 22.9% in the clinically examined control patients. The difference in frequency between patients with oral lichen lesions and those taken from files was statistically significant.

Factors affecting commencement and cessation of betel quid chewing behaviour in Malaysian adults.

BACKGROUND: Betel quid chewing is a common habit widely practiced in Southern Asian populations. However, variations are seen in the content of a betel quid across the different countries. Factors associated with commencement and cessation of this habit has been numerously studied. Unfortunately, data on Malaysian population is non-existent. This study aims to determine the factors associated with the inception and also cessation of betel quid chewing behaviour among Malaysian adults. METHOD: This study is part of a nationwide survey on oral mucosal lesions carried out among 11,697 adults in all fourteen states in Malaysia. The questionnaire included sociodemographic information and details on betel quid chewing habit such as duration, type and frequency. The Kaplan-Meier estimates were calculated and plotted to compare the rates for the commencement and cessation of betel quid chewing behaviour. Cox proportional hazard regression models were used to calculate the hazard rate ratios for factors related to commencement or cessation of this habit. RESULTS: Of the total subjects, 8.2% were found to be betel quid chewers. This habit was more prevalent among females and, in terms of ethnicity, among the Indians and the Indigenous people of Sabah and Sarawak. Cessation of this habit was more commonly seen among males and the Chinese. Females were found to be significantly more likely to start (p < 0.0001) and less likely to stop the quid chewing habit. Females, those over 40 years old, Indians and a history of smoking was found to significantly increase the likelihood of developing a quid chewing habit (p < 0.0001). However, those who had stopped smoking were found to be significantly more likely to promote stopping the habit (p = 0.0064). Cessation was also more likely to be seen among those who chewed less than 5 quids per day (p < 0.05) and less likely to be seen among those who included areca nut and tobacco in their quid (p < 0.0001). CONCLUSION: Factors that influence the development and cessation of this behaviour are gender, age, ethnicity, and also history of smoking habit while frequency and type of quid chewed are important factors for cessation of this habit.

Cancer and mortality among users and nonusers of snus.

Scandinavian moist snuff (snus) is claimed to be a safer alternative to smoking. We aimed to quantify cancer incidence among male snus users and to shed light on the net health outcome by studying their overall mortality. A cohort, comprised of 9,976 men who participated in a population-based survey, was compiled in 1973-74. Follow-up until January 31, 2002, was accomplished through record-linkages with nation-wide and essentially complete registers of demographics, cancer and causes of deaths. Adjusted relative risks among exposed relative to unexposed men were estimated using Cox proportional hazards regression. The cohort members contributed more than 220,000 person-years at risk for cancer. A statistically significant increase in the incidence of the combined category of oral and pharyngeal cancer among daily users of snus (incidence rate ratio 3.1, 95% confidence interval 1.5-6.6) was found. Overall mortality was also slightly increased (hazard ratio 1.10, 95% confidence interval 1.01-1.21). Although the combined previous literature on snus and oral cancer weigh toward no association, this population-based prospective study provided suggestive evidence of snus-related risks that cannot be lightly ignored.

Treatment of smarting symptoms in the oral mucosa by appliance of lingual acrylic splints.

UNLABELLED: The aim of the present study was to evaluate the relieving effect on smarting symptoms in the oral mucosa by the use of lingual acrylic splints. Recruited for the study were 53 persons, 48 women and 5 men, with smarting symptoms in the oral mucosa, not associated with general disease, and with signs of erythema, most often on the apex of the tongue, and/or crenated tongue. Symptoms were registered from the tongue in 49 cases, the palate in 28 cases and the lips in 15 cases. A lingual acrylic splint was applied in the lower jaw behind the front teeth, not covering the occlusal surfaces and it was kept in the mouth day and night. At an average the splint was used in 8 months. A group of 10 women was recruited for comparison. These women were just instructed to avoid tongue pressing for at least a two month period. All patients were asked whether the treatment affected the symptoms and they registered their opinion on a 100 mm VAS line with end effect points "not helped at all/deteriorated" and "now completely without symptoms". On the question whether the treatment had affected the symptoms, the average result was 55 mm and median value 64 mm. The treatment results were somewhat better among those with moderate initial symptoms compared to those with severe symptoms. Interestingly, in the group for comparison, symptom VAS values improved significantly from 60 to 41 mm (P < 0.05). CONCLUSION: Treatment of smarting symptoms in the oral mucosa may to a great extent be relieved by the application of an acrylic lingual splint. However, before using this splint method, an effort should be made to make the patient actively avoid tongue pressure.

Treatment of gingival lichen with free palatal grafts.

BACKGROUND: Recalcitrant gingival erythematous lichen planus/lichenoid lesions comprise a considerable therapeutic problem. The objective of this study was to evaluate the therapeutic effect of grafting keratinized oral palatal mucosa to the sites of gingival lichen. METHODS: In 12 patients 20 grafts were transplanted to buccal gingival lesions. Mean age of the patients was 59.8 +/- 7.1 years (range 46-71 years). The mean observation time was 32 +/- 32.7 months (range 5-97 months). RESULTS: On a 4-point clinical grade scale (0-3), 12 (60%) transplants showed complete healing grade 3, six (30%) grade 2 and two (10%) grade 1. CONCLUSIONS: Using oral mucosal grafts from the palatal mucosa for the treatment of recalcitrant erythematous gingival lichen planus/lichenoid lesions seems to be a promising treatment modality.

Oral lichen planus and oral lichenoid lesions: diagnostic and therapeutic considerations.

Several therapeutic agents have been investigated for the treatment of oral lichen planus (OLP). Among these are corticosteroids, retinoids, cyclosporine, and phototherapy, in addition to other treatment modalities. A systematic review of clinical trials showed that particularly topical corticosteroids are often effective in the management of symptomatic OLP lichen planus. Systemic corticosteroids should be only considered for severe widespread OLP and for lichen planus involving other mucocutaneous sites. Because of the ongoing controversy in the literature about the possible premalignant character of OLP, periodic follow-up is recommended. There is a spectrum of oral lichen planus-like ("lichenoid") lesions that may confuse the differential diagnosis. These include lichenoid contact lesions, lichenoid drug reactions and lichenoid lesions of graft-versus-host disease. In regard to the approach to oral lichenoid contact lesions the value of patch testing remains controversial. Confirmation of the diagnosis of an oral lichenoid drug reaction may be difficult, since empiric withdrawal of the suspected drug and/or its substitution by an alternative agent may be complicated. Oral lichenoid lesions of graft-versus-host disease (OLL-GVHD) are recognized to have an association with malignancy. Local therapy for these lesions rests in topical agents, predominantly corticosteroids.

Management of oral epithelial dysplasia: a review.

One of the goals of the fourth meeting of The World Workshop on Oral Medicine (WWOM IV) included a review of the pathophysiology and future directions for the clinical management of patients with oral epithelial dysplasia, excluding the lips and oropharynx. In the pathophysiology review of dysplasia since WWOM III (1998-2006), a wide range of molecular changes associated with progression of dysplasia to squamous cell carcinoma were found. These include loss of heterozygosity, dysregulation of apoptosis, aberrant DNA expression, and altered expression of numerous tissue markers. Based on the literature search, no single molecular pathway has been identified as the primary factor in progression of dysplasia to squamous cell carcinoma. A systematic review of medical (i.e., nonsurgical) management strategies for the treatment of dysplastic lesions has shown promising results in short-term resolution of dysplasia in the small number of studies that met eligibility criteria for review. However, because of the limited periods of follow-up reported in these studies, it remains unclear as whether resolution of dysplasia would actually be a long-term benefit of these interventions. This question is particularly germane when it is considered in the context of prevention of future development of squamous cell carcinoma. Because of the lack of randomized controlled trials that have shown effectiveness in the prevention of malignant transformation, no recommendations can be provided for specific surgical interventions of dysplastic oral lesions either.

A long-term follow-up study on the natural course of snus-induced lesions among Swedish snus users.

Snus-induced lesions (SILs) are mucosal changes that are regularly seen in users of moist snuff (snus). Their role in oral carcinogenesis remains undefined. Our aim was to assess the natural course of SILs over several decades. A cohort of 1,115 individuals with SILs, confirmed in 1973-1974 during a population-based survey was followed for 27-29 years through multiple record linkages with virtually complete population- and health registers. A sample (n = 267) of the cohort members were invited for reexamination after 19-22 years. Register-based follow-up through January 2002 revealed a total of 3 incident cases of oral cancer (standardized incidence ratio of 2.3, 95% CI 0.5-6.7), none of which occurred at the site of the original SIL. There was a strong association noted between the degree of SIL and current snus consumption. The SILs had disappeared in all 62 individuals who had permanently quit using snus. In no case did we observe an important clinical change for the worse among individuals who had decreased their use or continued unabatedly. While the incidence of oral cancer in this cohort of individuals with SILs tended to be higher than expected, we conclude that cancers rarely occur at the site of lesions observed in the distant past.

Cognitive impairment is associated with poor oral health in individuals in long-term care.

PURPOSE: The aim of this work was to study oral hygiene and cognition in patients in long-term care. MATERIALS AND METHODS: A representative sample of individuals in long-term care aged 67 years and above, from all 19 countries of Norway, was selected for the study. Trained local dental teams examined 1910 individuals--1358 from institutions and 552 living at home. Oral hygiene was assessed by means of a combined plaque and mucosal score (MPS), and cognition by means of a short version of Mini-Mental State Examination (MMSE-12). RESULTS: Mean age was 84.2 years and the age range was 67-106 years. Over 70% were cognitively impaired. Cognitive impairment increased with age and was more prevalent in institutionalised individuals compared to those living at home. Poor oral status was more prevalent among individuals with cognitive impairment. CONCLUSION: The results of this study indicate that a large proportion of individuals in long-term care in Norway show cognitive impairment. A high proportion of these has a poor oral status. Thus, they carry a high risk of developing dental caries. Obviously, there is a demand for careful and close surveillance of oral hygiene and oral health in individuals in long-term care, and especially of those cognitively impaired.