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61.
Variations in the dental anatomy are found in all teeth. Knowledge of these variations, particularly concerning the location and treatment of all canals, is very important for the success of the endodontic therapy. The purpose of this study is to present a clinical case of a maxillary second molar with three palatal canals, two mesio-buccal and one disto-buccal canal. This report serves to remind clinicians that such anatomical variations should be taken into account during endodontic treatment of the maxillary molars.  相似文献   
62.
We operated on a 65-year-old woman and removed a solitary fibrous tumour from her oral mucosa. Microscopically we found marked atypia, abundant necrosis, increased number of mitotic figures (>4 in 10 high-power fields) and hypercellularity. The tumour cells were strongly stained for CD34. There has been no recurrence after 18 months.  相似文献   
63.
OBJECTIVE: To evaluate the likelihood of caries increment in schoolchildren, based on their prior caries experience. MATERIAL AND METHODS: We undertook a longitudinal study in 452 six-to-nine year olds between 1999 and 2001 in Mexico, with dental exams conducted by two standardized examiners (kappa>0.85). The dependent variable was the DMFT increment, dichotomized as without increment, and at least one unit of increment. Independent variables estimated caries experience at baseline. Data were analyzed using non-parametric tests and generalized linear models (log-binomial) to calculate relative risk (RR) adjusted for age and sex. RESULTS: The percentage of caries-free children diminished by 20.5% from 1999 to 2001. DMFT index increased two-fold, from 0.25+/-0.70 in 1999 to 0.77+/-1.30 in 2001 (p<0.001). The overall risk for this sample was 24%. The DMFT increment was higher (p<0.001) in children with DMFT>0 and dmft>0 in 1999 (RR=1.89, 95% CI=1.37-2.62; RR=2.71, 95% CI=1.94-3.76, respectively). The likelihood for DMFT increment from the 1999 levels was: (1) 2.78 times higher (95% CI=2.06-3.76) if schoolchildren had caries in any of the first permanent molars and (2) 1.62 times higher (95% CI=1.20-2.19) if schoolchildren were affected by high severity caries at baseline. CONCLUSIONS: Both caries prevalence and mean DMFT had significant increments in 18 months. Dental caries in the primary (dmft) and permanent (DMFT) dentitions at baseline are goods indicators of subsequent caries development in this group of children in a medium income country. This relationship became stronger when the occurrence of caries in the first permanent molars was included.  相似文献   
64.
65.
Supernumerary teeth are an infrequent developmental anomaly that can appear in any area of the dental arch and can affect any dental organ. Multiple supernumerary teeth, or hyperdontia, is rare in people with no other associated diseases or syndromes. Conditions commonly associated with hyperdontia include cleft lip and palate, trichorhinophalangeal syndrome, cleidocranial dysplasia, and Gardner's syndrome. A black girl, aged 11 years 8 months, came for consultation; radiographs showed 81 teeth: 18 deciduous, 32 permanent, and 31 supernumerary. The main concern initially was to determine whether she was syndromic, and she was referred to a geneticist. G banding analysis showed pericentric inversion of chromosome 9; the chromosome formula was 46, XX, inv (9) (p13q21). Orthodontic treatment for this patient will be a clinical challenge because of the great number of teeth to be extracted and the alterations in the shapes of the teeth. Treatment goals should be established by a multidisciplinary team, where oral surgeon, orthodontist, periodontist, and prosthodontist come together to solve a medical and dental puzzle, eliminating the pieces that do not fit and searching for new ones to obtain an occlusion that will give the patient physiologic conditions of normality and esthetic satisfaction.  相似文献   
66.
Background: To our knowledge, prospective studies (matched for sex, smoking, and diabetes) that investigated the influence of compliance in the progression of periodontitis and tooth loss in periodontal maintenance therapy (PMT) programs were not previously reported. Methods: A total of 58 regular complier (RC) and 58 erratic complier (EC) individuals were recruited from a prospective cohort with 238 patients under PMT and matched by sex, diabetes, and smoking habits. A full‐mouth periodontal examination that included bleeding on probing (BOP), probing depths (PDs), clinical attachment levels, and number of teeth were determined at all PMT visits during a 3‐year interval. The influence of variables of interest was tested through multivariate logistic regression. Results: The progression of periodontitis and tooth loss was significantly lower among RC compared to EC patients. A higher progression of periodontitis was observed among EC patients who smoked. The final logistic model for the progression of periodontitis in the RC group included smoking (odds ratio [OR]: 4.2) and >30% of sites with BOP (OR: 2.8), and the final logistic model for the progression of periodontitis in the EC group included smoking (OR: 7.3), >30% of sites with BOP (OR: 3.2), PDs of 4 to 6 mm in 10% of sites (OR: 3.5), diabetes (OR: 1.9), and number of lost teeth (OR: 3.1). Conclusions: RC patients presented a lower progression of periodontitis and tooth loss compared to EC patients. This result highlighted the influence of the pattern of compliance in maintaining a good periodontal status. Moreover, important risk variables such as smoking and diabetes influenced the periodontal status and should be considered when determining the risk profile and interval time for PMT visits.  相似文献   
67.
This study evaluated the effect of the adhesive application mode and fiber post translucency on the push-out bond strength to dentin. Bovine roots were endodontically treated, and 10 roots were used for each adhesive application mode: PB (Prime&Bond 2.1), PB + SC (Self-cure activator), PB + SBM (Scotchbond Multi-purpose adhesive system), BB (Brush&Bond), BB + CAT (chemical catalyst), and BB + SBM. The translucent Light-Post and Aestheti-Post were cemented. The roots/cemented posts were transversally sectioned to originate three thirds (cervical, middle, and apical). The push-out test was performed, and the failure mode of fractured specimens was analyzed. There was no difference between the fiber posts. For PB and BB, the use of hydrophobic adhesive resin SBM increased post bond strength. The use of SC and CAT catalyst did not affect the push-out bond strength values. The apical third presented the lowest bond strengths.  相似文献   
68.
Unhealthy oral habits may be involved in the etiology of a malocclusion, since they may affect development of the orofacial region. There is little information on the habit of sucking the lower lip, to which practitioners attribute less clinical consequences. However, lower lip sucking is a harmful habit which appears frequently in children, especially during situations requiring increased attention and mental concentration. In patients presenting lower lip sucking, strong contractions of the lower lip's orbicular's muscle and the mentalis muscle, associated with hypertonicity of the upper lip caused by sucking, has to be balanced by lingual thrusting during the act of deglutition. A case is presented in which failure to identify the habit of lower lip sucking led to an atypical lesion on the tongue, caused by the tongue's impaction against the orthodontic appliance prescribed to correct a malocclusion. The recognition and elimination of an unhealthy habit is of great importance in diagnosis and the establishment of a treatment plan, so that undesirable complications can be avoided.  相似文献   
69.
70.
Cerebrovascular accident (CVA) is the third cause of death in industrialized countries, following cardiovascular disease and cancer. It is therefore a significant public health issue, not only due to its high incidence, but also to the high costs involved in the physical and psychological rehabilitation of these patients. Dental Practitioners, as health care providers, ought to play their part in this issue and contribute, within their means, to the early detection of patients at risk of having a CVA. Since the eighties, different authors have described the possibility of detecting calcified atheroma plaques located at carotid artery bifurcation through panoramic radiograph. In this way, the Dental Practitioner s possibilities in this field have been extended. However, this new use of panoramic radiograph must overcome certain obstacles before it is implemented as a new screening method for patients at risk of having a CVA. Amongst these, we would have, on the one hand, the assessment of the real clinical significance, as regards prognosis, of atheroma plaque calcification as well as its usefulness as a factor for predicting the appearance of CVA symptoms and, on the other hand, the possibility of making a correct differential diagnosis regarding other calcified structures that may appear on panoramic radiograph.  相似文献   
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