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AIM: To present two clinical cases and demonstrate that occlusal trauma may affect healing of periapical pathoses. SUMMARY: Two teeth with periradicular disease did not respond successfully to conventional root canal treatment or endodontic surgery. Occlusal adjustment was finally performed on both cases. After occlusal adjustment, uncomplicated healing and periapical repair occurred in both cases. The findings in these two cases suggest that occlusal trauma may play a role in the healing of periapical pathoses. KEY LEARNING POINTS: Occlusal trauma is positively correlated with changes in periodontal tissues. Although experiments in animals have shown that application of forces to teeth will not induce further periodontal destruction, we believe that some failures of root canal treatment may be due to the presence of occlusal trauma modulating the responses of inflamed periapical tissues or apical pathoses with persistent infection.  相似文献   
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Abstract – Objectives: The Early Childhood Oral Health Impact Scale (ECOHIS) is a recently developed oral health‐related quality of life instrument designed to assess the impact of oral health problems in 0–5‐year‐old children. It has previously been validated as discriminative instrument. The goal of this study was to investigate the responsiveness to change of the ECOHIS. Methods: Data were collected from a convenience sample of 101 parents of 0–5‐year‐old children attending a hospital dental clinic for dental treatment. The ECOHIS was completed by parents prior to dental treatment and 2 weeks later. Subjects were also asked a global transition judgement concerning change between the second and first completion of the ECOHIS instrument. Responsiveness to change of the ECOHIS was analysed through: (i) a comparison of ECOHIS change scores with a global transition judgment by study subjects; (ii) an assessment of the statistical significance of within‐group change in scores over time for groups reporting improvement, stability and deterioration; (iii) an estimation of the ECOHIS’s sensitivity; and (iv) an investigation the effect size of the ECOHIS. Results: Of the 101 subjects recruited, 94 had full datasets. Their data were used for the analyses reported in this paper. Pre‐ and post‐treatment distributions of ECOHIS scores were strongly distributed towards no oral health impacts. Among the 94 subjects, 51.1% reported improvement, 42.6% reported no change and 6.4% reported deterioration following treatment, using the global transition judgement. The mean ECOHIS change scores for these three groups were ?0/9, +0.7 and +6.5 respectively, although none of the within‐group changes were statistically significant. The effect size for those reporting improvement was small (0.15) but for those reporting deterioration was moderate‐to‐large (0.69). Sensitivity ranged from 0.61–0.79 depending on the size of the cut‐off point, with a change of 3 points demonstrating the best sensitivity to false positive ratio (0.79 versus 0.41 respectively). Conclusion: In this sample with low levels of problems, the ECOHIS has demonstrated some limited ability to respond to change. Further work in a larger sample with higher levels of problems is needed to investigate the instrument’s ability to respond to change when it has occurred.  相似文献   
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OBJECTIVES: The objective of this study was to develop and test the feasibility and validity of a willingness to pay (WTP) tool in a dental setting. METHODS: A questionnaire measured individuals' preferences among alternative treatments for periodontal disease and the maximum they would be willing to pay for their treatment of choice in terms of dental insurance premiums. The questionnaire provides detailed information, in probabilistic terms, of the risks and benefits of treatment choices for moderate to advanced adult periodontitis. It was pilot tested on 23 periodontal patients and 18 dental school faculty and staff. RESULTS: The majority (92.6%) felt the questionnaire was an accurate representation of treatments and outcomes, establishing face and content validity. In terms of construct validity, four hypotheses were tested: (1) manipulation of the outcomes of the preferred treatment led to a predictable shift in preferences for 38 subjects (92.7%); (2) although periodontal patients were not more likely to choose periodontal surgery than nonpatients (P = .14), those with a history of surgery were more likely to choose surgery again (P = .06); (3) WTP was positively related to income level (P = .05); and (4) subjects were willing to pay more for coverage for themselves than for others. Periodontal surgery was the preferred treatment for moderate to advanced periodontal disease, and was more strongly preferred than other choices (i.e., a higher WTP) for all income groups. The intraclass correlation coefficient for treatment preferences was 0.95 (P < .001) and the kappa for WTP was 0.78 (P < .001). CONCLUSION: This pilot study supports some of the criteria concerning validity of the WTP questionnaire to measure preferences for alternative periodontal therapies. Further testing on larger samples is required to confirm these results.  相似文献   
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A case of Ludwig's angina is reported in a 60-year-old woman who was discovered to have squamous-cell carcinoma of the tongue and floor of the mouth during intubation for airway management. This report emphasizes the need to consider infection of oral malignancies of the tongue and floor of the mouth in the etiology of Ludwig's angina when an odontogenous origin cannot be demonstrated. It also illustrates the value of bronchoscopy-directed nasotracheal intubation for diagnosis and airway management in such cases.  相似文献   
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Abstract The experiments were performed in 13 dogs; nine of the animals had initially a healthy periodontium and four had experimental periodontitis. Trauma from occlusion was created in all dogs according to a technique described previously. The dogs were sacrificed after 7, 14, 30 and 180 days of the experiment. Prior to sacrifice colloidal carbon was injected intravenously. The degree of vascular labelling and leucocyte infiltration as well as osteoclastic activity and the size of the marginal periodontal ligament were assessed in biopsy sections. The findings showed that dogs with a healthy periodontal lesion (Group A) differed in their reactions to a jiggling type of occlusal trauma when compared to dogs with an established periodontal lesion (Group B). Whereas the periodontal ligament in Group A had become adapted to the altered occlusion by the end of 6 months of experiment, that of Group B still showed increased vascular leakage, leucocyte migration and osteoclastic activity.  相似文献   
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