Tooth loss was linked with poorer nutrition even among dentists.

Recently, various authors have proposed the interesting idea that occlusal force may be a principal factor in cervical lesions of the tooth. It is speculated that the lateral force in non-ideal mastication causes the tooth to bend and that the resulting tensile stress damages the enamel surface. In this study, we carried out stress analysis on the upper central incisor and the lower first molar using the plastic-elastic deformation theory with two-dimensional finite element method (FEM). The essential feature that the tensile yield strength is much smaller than the compressive one was taken into account. Our results suggested that oblique loading on the tooth stretches the enamel surface near the cemento-enamel junction and causes plastic deformation which eventually leads to the cervical lesion.

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Background:The vitamin D receptor (VDR) is involved in a variety of biological processes, such as bone metabolism and modulation of the immune response. Recent findings suggest that the pathway involving bone mineral density-mediated effects is important for the development of periodontitis, but their effects of combined VDR gene polymorphisms have not been confirmed on periodontitis. We assessed the relationship between ApaI, BsmI, and FokI VDR polymorphisms and the risk of severe chronic periodontitis among Japanese adult men. Materials and Methods:In a cross-sectional study, we examined 97 unrelated healthy Japanese men (mean age: 45.6 years, range: 22-59). A clinical examination was performed at a worksite health checkup, and information was obtained using a self-reported questionnaire. DNA was extracted from whole blood, and the VDR ApaI, BsmI, and FokI polymorphisms were genotyped using polymerase chain reaction. Results: F-carriers of FokI VDR polymorphisms were less likely to develop severe chronic periodontitis than non-F-carriers (p = 0.09). The ApaI and BsmI VDR polymorphisms did not show significant differences in the alleles or genotypes between the subjects with or without severe chronic periodontitis. The haplotype analysis of the three combined VDR polymorphisms revealed that the Abf homozygote had a notably higher prevalence of severe chronic periodontitis than the others, and adjustments for age, smoking status, number of teeth present, and prevalence of diabetes did not change this association (OR = 7.5; 95% CI = 1.6-34.4; p = 0.01). Conclusion:The VDR haplotype constructed from the ApaI, BsmI, and FokI polymorphisms is related to the risk of severe chronic periodontitis in Japanese men.

The aim of this study was to evaluate the periodontal parameters of osseointegrated dental implants. The condition of the peri-implant mucosa was assessed using periodontal parameters, i.e., of plaque index, bleeding on probing, probing pocket depth, probing attachment level and Periotest scores as well as a radiographic parameter, over a 4-year follow-up period. 32 non-submerged ITI dental implants, all placed in the mandible, were studied in 12 patients who had good oral hygiene. All patients were regularly recalled at 6-month intervals. The overall implant success rate was 100%. None of the implants showed any signs of inflammation, radiographic bone loss or any detectable mobility during the follow-up period. Methods similar to those used to evaluate the natural dentition were effectively employed to assess the clinical status of the dental implants. The diagnostic value of these parameters could not, however, be determined from this study due to the absence of any peri-implant tissue complications. The results indicated that some periodontal parameters of healthy peri-implant mucosa might be slightly different from healthy periodontal tissue.

The purpose of this study was to investigate the practices, knowledge, confidence, and attitude toward oral cancer among Japanese oral health professionals (J-OHPs) and to identify Japanese-specific problems in oral cancer practices by comparing them between Japan and Australia. A questionnaire survey regarding oral cancer practices among Australian oral health professionals (Au-OHPs) was conducted in Australia in 2014-2015. The questionnaire was translated into Japanese, and a Web-based questionnaire survey was conducted among 131 Japanese dentists (J-Dentists) and 131 dental hygienists (J-DHs) in 2016. To compare the J-OHPs' findings with the Au-OHPs', the data of Australian dentists (Au-dentists) and Australian dental hygienists (Au-DHs) were extracted from the Australian survey. Those findings were then compared via a statistical analysis. Eighty-two J-Dentists, 55 J-DHs, 214 Au-Dentists, and 45 Au-DHs participated in this study. Only 34.1 % of J-Dentists and 36.4 % of J-DHs performed oral cancer screenings on their patients; J-OHPs were significantly less likely to perform them than Au-OHPs. The level of knowledge and confidence regarding oral cancer among JOHPs were significantly lower than among Au-OHPs. About 90 % of J-OHPs felt that they needed additional training in oral cancer practices. Less than 40 % of J-OHPs performed oral cancer screenings in their patients. The low level of knowledge and confidence regarding oral cancer among JOHPs may contribute to their low performance of oral cancer practices. Therefore, further education and training programs for oral cancer practices should be provided to Japanese OHPs for the prevention and early detection of oral cancer.

Helicobacter pylori infection, which causes peptic ulcers and gastric cancer, is considered a possible cause of halitosis. Recently, the oral cavity was identified as a possible H. pylori reservoir, particularly in the presence of periodontal disease, which is a cause of halitosis. The purpose of this study was to evaluate by PCR the prevalence of oral H. pylori in the saliva of subjects complaining of halitosis. Samples were obtained from 326 non-dyspeptic subjects, comprising 251 subjects with actual malodour and 75 subjects without halitosis. DNA was extracted from the samples, and the presence of H. pylori and periodontopathic bacteria including Porphyromonas gingivalis, Treponema denticola and Prevotella intermedia was examined by PCR. H. pylori was detected in 21 (6.4 %) of 326 samples. The methyl mercaptan concentration and periodontal parameters including tooth mobility, periodontal pocket depth (PPD) and occult blood in the saliva were significantly greater in the H. pylori-positive subjects. Each of the periodontopathic bacteria was also detected at a significantly higher frequency in the H. pylori-positive subjects. Among those patients with a PPD of ¢5 mm and a tongue coating score of ¡2, no difference was observed in oral malodour levels between the H. pylori-positive and -negative subjects. However, the presence of occult blood in the saliva and the prevalence of Prevotella intermedia were significantly greater in the H. pylori-positive subjects. H. pylori was detected in 16 (15.7 %) of 102 subjects with periodontitis, suggesting that progression of periodontal pocket and inflammation may favour colonization by this species and that H. pylori infection may be indirectly associated with oral pathological halitosis following periodontitis. INTRODUCTIONHelicobacter pylori is a spiral, microaerophilic, Gramnegative bacterium that colonizes the human gastrointestinal tract, primarily the stomach (Covacci et al., 1999). It is also believed to be responsible for gastritis and peptic ulcers, and is a risk factor for gastric cancer (Dunn et al., 1992; Parsonnet et al., 1991;Warren & Marshall, 1983); however, the mode of transmission of H. pylori is poorly understood. Several studies have detected H. pylori in the human oral cavity, particularly in patients with gingivitis or chronic periodontitis (Anand et al., 2006; Gebara et al., 2006;Souto & Colombo, 2008), and have thus suggested that the oral cavity is the primary extragastric reservoir for H. pylori. In contrast, other studies have failed to find evidence supporting the role of the oral cavity as a major reservoir of H. pylori (Czesnikiewicz-Guzik et al., 2004;Loster et al., 2006).Halitosis is a common problem in humans, and oral malodour is largely caused by periodontitis, tongue debris, poor oral hygiene, deep caries, inadequately fitted restorations and endodontic lesions (Rosenberg et al., 1991;Tonzetich, 1977;Yoneda et al., 2006); specifically, it is primarily the result of the microbial metabolism of amino acids in local debris (Scully et al.,...

ObjectiveOral cenesthopathy is characterized by foreign body sensations without medical and dental evidence for them. It is thought to be a rare disease in psychiatry, but many patients are visiting dental clinics seeking treatment to remove a foreign body. Even though the features of oral cenesthopathy might be different between a psychiatric clinic and a dental clinic, there has been no clinic-statistical study from dentists. In this study, we report a clinico-statistical study of patients with oral cenesthopathy in dentistry.MethodsThis is a retrospective chart review of 606 outpatients with oral cenesthopathy in Tokyo Medical and Dental University from April 2010 through to March 2015.ResultsA total of 159 male and 447 female patients were included in this study. The mean age was 62.08 years, and female patients were older than male patients. The trigger of the dental treatment and the acute phase of depression at the onset were significantly related (p=0.037). Only 128 patients (36%) had clinically significant improvement after 6 months of pharmacotherapy. No history of psychiatric disorders (odds ratio [OR] 0.479 [95% confidence interval {CI}: 0.262–0.875], p=0.017) and longer duration of illness (>18 months) (OR 2.626 [95% CI: 1.437–4.799], p=0.002) were significant factors for clinical outcomes.ConclusionPatients with oral cenesthopathy in our clinic were predominantly elderly female patients. Dental treatment in the acute phase of depression might be a risk factor for oral cenesthopathy. Therefore, comprehending the situation of psychiatric disorder and obtaining adequate informed consent might be required to prevent the trouble concerning oral cenesthopathy.