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21.
A case history and brief literature review of oral submucous fibrosis is presented. This condition is most frequently found in the Indian subcontinent and only rarely encountered elsewhere. The aetiology is considered to be related to dietary habits and customs found in the population. The condition has a known malignant potential. With increasing migration to Australia from the Indian subcontinent the condition should be known and recognized by clinicians.  相似文献   
22.
Objectives: The objectives of this study is to explore the relationship between pediatric patients' orthodontic treatment need, the patients' assessments of their smile‐related quality of life (QoL), their parents' proxy assessment of their child's QoL and own assessments of their child's smile, and the patients' objectively assessed smiling patterns. Methods: Survey data were collected from 102 patients (53 boys/49 girls; age range: 9–13 years) and their parents. Orthodontic treatment need was assessed with the Index of Complexity, Outcome, and Need (ICON). Smiling patterns were determined by videotaping patients' smiles while they watched a cartoon. Thirty predetermined sections of these tapes were then assessed by two independent raters to measure the patients' smiling patterns. Results: The aesthetic component and total ICON scores correlated with the patients' smile‐related QoL (r = 0.25; P = 0.014/r = 0.23; P = 0.024), parental proxy assessments of the child's smile‐related QoL (r = 0.29; P = 0.004/r = 0.26; P = 0.009), the parents' own assessments of their child's smile (r = 0.32; P = 0.002/r = 0.29; P = 0.005), and the number of negative adjectives chosen by the parents to describe their child's smile (r = 0.32; P = 0.002/r = 0.30; P = 0.004). Although the smiling patterns were correlated with the patients' smile‐related QoL responses (height of smile: r = 0.29; P = 0.005/number of teeth shown: r = 0.30; P = 0.004), the ICON scores were not correlated with the patients' smiling patterns. Conclusions: Objectively assessed orthodontic treatment need correlates with the patients' and parents' assessments of the child's smile‐related QoL scores. However, while objective smiling patterns are related with the patients' smile‐related QoL, they are not correlated with the patients' orthodontic treatment need.  相似文献   
23.
The aim of this study was to compare the shape of exposed dentinal surfaces caused by abrasion and erosion with a view to developing a diagnostic clinical test. The study material consisted of 80 natural teeth and 129 dental models obtained from Australian Aborigines known to display considerable dental abrasion due to their diet, and dental models of 37 Caucasians diagnosed with dental erosion through detailed history and dietary analysis. Polyvinyl siloxane impressions were obtained of all occlusal surfaces with dentinal scooping in both the 'abrasion' and 'erosion' groups. All impressions were sectioned buccolingually through the deepest point of the scooped dentine, and then the profiles were photocopied at X 2 magnification. The breadth and depth of dentinal profiles were measured to an accuracy of 0.1 mm, enabling ratios of depth:breadth to be determined, and the position of the deepest part of each scooped surface was recorded. The mean depth:breadth ratio of scooped dentine was significantly greater in the Aboriginal natural teeth (0. 19±60.06, mean±SE) than in the Aboriginal dental models (0.15±0.04). Both Aboriginal natural teeth and models with abrasion showed significantly smaller ratios (p<0.05) than the Caucasian models showing erosion (0.33±.07). Furthermore, in the abrasion samples, the deepest region of the scooped dentine tended to be lingually placed more often in maxillary teeth but buccally placed more often in mandibular teeth (p<0.05). These results indicate that scooped dentine on abraded occlusal surfaces of teeth displays significant differences in shape compared with that caused mainly by erosion.  相似文献   
24.
3种检查方法对早期邻面龋诊断水平的评价   总被引:1,自引:1,他引:1  
目的 :体外评价比较平行投照的牙合翼片 (BWR)、激光荧光法 (LF)和模拟临床检查 (CE)等 3种诊断方法对早期邻面龋的诊断水平。方法 :分别对模拟临床排列的 81颗离体牙的 162个早期龋损和正常邻面进行BWR、LF、CE检查 ,以组织学结果为金标准 ,评价准确性、敏感性、特异性 ,以及与组织学深度的相关性和一致性水平等指标。结果 :BWR的准确性、敏感性、一致性水平明显优于CE和LF ,但敏感度仍属中等 ,观察者自身一致性不理想。结论 :平行投照的BWR是目前较好的临床诊断方法 ,对于早期邻面龋有一定的诊断能力 ,但诊断水平尚有待提高。LF法诊断效果总体上不如BWR法 ,主要与其对于邻面的可操作性差有关。  相似文献   
25.
牙合面尚未成洞龋早期诊断方法的进展   总被引:1,自引:0,他引:1  
近20年来,由于预防工作的广泛展开,特别是氟化物的广泛应用,龋病的发病率明显下降.但牙合面龋所占比例却有所增加,常表现为在表面正常的牙釉质下向深层发展.因此,如何对尚未成洞龋作出早期正确诊断已成为口腔医生日益关注的问题,传统的视诊、探诊法已远远不能满足要求,迫切需要开发新型、有效的龋病诊断技术.本文介绍几种牙合面尚未成洞龋的诊断方法.  相似文献   
26.
Neural networks are a new type of computing algorithm. They are especially useful in pattern recognition. In this study we applied neural networks to the prediction of lymph node metastasis of patients with oral cancer. A data set of 1,116 lymph nodes verified histopathologically was used to train and evaluate the neural networks. Various three-layer feed-forward networks with a back-propagation algorithm were employed in this study. Performance of the neural networks was compared with that of radiologists and discriminant analysis (Quantification theory type II). Neural networks had a sensitivity of 80.6% and a specificity of 94.6%. Diagnostic accuracy of the neural networks was 93.6%, which was comparable to those of discriminant analysis and clinical radiologists.  相似文献   
27.
C Scully 《Oral diseases》1997,3(Z1):S1-S6
AIDS was first observed in 1981. The World Health Organisation has estimated that over 6 million AIDS cases had occurred by late 1995 but that only one-third had been reported. There is an annual increase worldwide of 20%, but in Asia it is in excess of 150% each year. HIV-1 can be classified into two major groups: M which contains 10 subtypes and O which contains several heterogenous viruses. HIV-2, found mainly in Africa, contains at least five subtypes. Combination therapies with nucleoside analogues are now recommended.  相似文献   
28.
Electric pulp testing (EPT) has been available for more than a century and used in dental practices worldwide. This article provides an overview of this diagnostic aid. The PubMed database from 1953 was used initially; the reference list for pulp testing featured 1071 articles, and for EPT identified 121 papers. A forward search was undertaken on these articles and using selected author names. Potentially relevant material was also sought in contemporary endodontic texts, while older textbooks on endodontics, operative dentistry and pain revealed historic information and primary research not found electronically. A short account of the innervation of the pulp is followed by an historic overview. Clinical considerations discussed include tooth isolation, glove wearing and tester electrode placement. Orthodontic treatment, pacemaker wearing and patient medications are considered. Research applications are also discussed. While EPT is valuable, no single pulp testing technique can reliably diagnose all pulp conditions. Careful collection of patient history regarding the problem tooth and prudent use of appropriate radiographs are also helpful. The shortcomings of electric tests, especially in the case of immature and concussed teeth, must be understood. The demeanour of the patient and the responses given by control teeth also require careful consideration.  相似文献   
29.
We report herein a very rare case of actinomycosis originating in the submandibular gland in which malignancy was suspected. A 56-year-old man visited our clinic with a chief complaint of painless mass in the right submandibular region. From the imaging diagnosis, we suspected malignant tumor in the submandibular gland. Under general anesthesia, right radical neck dissection and excision of the submandibular gland with the above mass were carried out. Histopathological diagnosis of actinomycosis in the submandibular gland was made. Because the focus exists within the gland, we consider this case as a primary submandibular gland actinomycosis. Two years postoperatively, the tumor has not recurred. On diagnosis, it is necessary to differentiate this disease with other benign or malignant tumors.  相似文献   
30.
Objectives: This report describes the training of dental examiners participating in two dental caries clinical trials and reports the inter‐ and intra‐examiner reliability scores from the initial standardization sessions. Methods: Study examiners were trained to use a modified International Caries Detection and Assessment System II system to detect the visual signs of non‐cavitated and cavitated dental caries in adult subjects. Dental caries was classified as no caries (S), non‐cavitated caries (D1), enamel caries (D2), and dentine caries (D3). Three standardization sessions involving 60 subjects and 3,604 tooth surface calls were used to calculate several measures of examiner reliability. Results: The prevalence of dental caries observed in the standardization sessions ranged from 1.4 percent to 13.5 percent of the coronal tooth surfaces examined. Overall agreement between pairs of examiners ranged from 0.88 to 0.99. An intra‐class coefficient threshold of 0.60 was surpassed for all but one examiner. Inter‐examiner unweighted kappa values were low (0.23‐0.35), but weighted kappas and the ratio of observed to maximum kappas were more encouraging (0.42‐0.83). The highest kappa values occurred for the S/D1 versus D2/D3 two‐level classification of dental caries, for which seven of the eight examiners achieved observed to maximum kappa values over 0.90. Intra‐examiner reliability was notably higher than inter‐examiner reliability for all measures and dental caries classifications employed. Conclusion: The methods and results for the initial examiner training and standardization sessions for two large clinical trials are reported. Recommendations for others planning examiner training and standardization sessions are offered.  相似文献   
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