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81.
Resin bonded bridges have become established as a treatment option for replacing missing teeth. Their development can be traced to the work of Rochette who used a macro mechanically bonded metal framework to stabilize mobile teeth. Adaptations of Rochette's concept, using natural teeth as pontics, have been presented. The use of a natural tooth has aesthetic and psychological advantages for the patient. The high failure rate of natural tooth pontics may be explained by a lack of support for the tooth on the metal framework. A clinical report is presented to illustrate a previously unreported technique to improve pontic support.  相似文献   
82.
PURPOSE: The objective of this study was to report our experience with the treatment of 30 odontogenic keratocyst (OKC) patients with a conservative treatment protocol based on decompression with reference to the recurrence rate. PATIENTS AND METHODS: Twenty-eight patients (19 females, 9 males) with 30 OKCs attended the OMS Department of the Piracicaba Dental School of Campinas State University between 1995 and 2003. Age range was 13 to 69 years (mean, 30 years of age). Initial biopsy was carried out in all patients and the OKCs were diagnosed after histological examination by the Oral Pathology Department. The cases were treated according to the treatment employed in this department, consisting mainly of decompression and curettage of the remaining lesion. The average follow-up for the 28 cases was 24.89 months (+/-9.74). RESULTS: The majority of the lesions (16 patients, 53.3%) occurred in the angle of the mandible and mandibular ramus. The most common histological pattern of OKC was parakeratinized (66.6%) and 13 of 28 patients presented impacted teeth associated with the lesion. The mean time for decompression was 9.27 months. Recurrence occurred in 4 patients (14.3%) with 4 OKCs. These patients were treated initially with decompression and curettage (2 cases), or with decompression only (2 cases). All the cases were monitored continuously with panoramic radiographies and clinical evaluations. CONCLUSIONS: The treatment protocol for OKC based on decompression offers a conservative and effective option with low morbidity and similar recurrence rates to those reported in the literature. The systematic and long-term post-surgical follow-up is considered to be a key element for successful results.  相似文献   
83.
The early childhood caries epidemic has prompted a look at predoctoral clinical dental education in pediatric dentistry. The purpose of this study was to examine the contribution of community-based clinical education (CBE) to procedural and patient diversity in predoctoral pediatric dental education. Using procedural and demographic data from pediatric clinical experiences of the dental class of 2007 at The Ohio State University College of Dentistry, profiles of patient diversity, clinical pediatric dental procedures, and student efficiency were developed for both CBE sites and the campus-based clinic. Ninety-two students performed 16,523 procedures on children in the fourth year in CBE sites in the community compared to 4,268 on campus in their third year. Pediatric-dedicated CBE sites accounted for almost 12,000 pediatric dental procedures. Approximately 56 percent of children treated at CBE sites were minorities. CBE sites accounted for most of the dental student restorative experience for pediatric patients for the Class of 2007, giving each student on average multiple restorative procedures. The campus-based clinic provided largely diagnostic and preventive procedures but few restorative opportunities. We conclude that community-based dental clinical education presents an opportunity to enhance pediatric predoctoral student clinical experiences in both quantity and diversity.  相似文献   
84.
BACKGROUND: Saliva has been studied for the presence of subgingival pathogens in periodontitis patients. With the anaerobic culture technique, the discrepancy between salivary recovery and subgingival presence has been significant, which makes this approach not suitable for practical use in the microbial diagnosis of periodontitis patients. The real-time polymerase chain reaction (PCR) technique represents a very sensitive technique to detect and quantify bacterial pathogens. The aim of the study was to compare the presence and numbers of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia, and Micromonas micros in subgingival plaque and mouthwash samples by the anaerobic culture and real-time PCR techniques. METHODS: Pooled subgingival plaque samples and 10-ml mouthwash samples were collected from 21 adult patients with periodontitis and analyzed by quantitative anaerobic culture and real-time PCR for A. actinomycetemcomitans, P. gingivalis, T. forsythensis, P. intermedia, and M. micros. RESULTS: The detection frequency of A. actinomycetemcomitans, P. gingivalis, and T. forsythensis in subgingival plaque was identical by culture and real-time PCR and was higher for P. intermedia and M. micros by real-time PCR. The highest detection frequencies for the target bacteria were found in mouthwash samples by real-time PCR. The additional value of the real-time PCR to detect target bacteria was 38% for P. gingivalis, 73% for T. forsythensis, 77% for P. intermedia, and 71% for M. micros. The sensitivity to detect target species in mouthwash by real-time PCR was 100% for all test species except for P. intermedia (93.8%). CONCLUSIONS: Rapid detection and quantification of periodontal pathogens in mouthwash samples are possible by real-time PCR. The procedure is significantly less time-consuming than subgingival sampling with paper points. This approach to detect major periodontal pathogens in mouthwash samples may simplify microbial diagnosis in periodontitis patients and may be used to monitor periodontal treatment.  相似文献   
85.
There are several factors to consider when restoring failing dentition in the anterior region. While a tooth can be replaced with an implant, achieving an esthetic result is challenging. The dental team must evaluate numerous criteria to define the optimal treatment plan. Among the considerations are whether to extract the tooth and perform immediate implant replacement or to perform a ridge preservation procedure. This article presents diagnostic determinants to help decide the most appropriate course of therapy to achieve functional and esthetic results.  相似文献   
86.
The purpose of this study was to compare the mesiodistal tooth angulations determined with a typodont/skull testing device with the images of mesiodistal tooth angulations from 4 contemporary panoramic units (OP 100, Cranex 3+, Orthophos, PM 2002 EC). A typodont testing device was constructed, and the true mesiodistal tooth angulations relative to an orthodontic archwire were determined with a 3-dimensional coordinate-measuring machine and custom-designed software. A human skull served as the matrix into which the typodont was fixed for imaging. The skull was repeatedly imaged and repositioned 5 times for each panoramic unit. The images were scanned and digitized with custom software to determine the image mesiodistal angulations. Results revealed that the majority of image angles from the 4 panoramic units were statistically significantly different from the true angle measurements. However, definite trends were noted among the panoramic units. For the maxillary teeth, the images projected the anterior roots more mesially and the posterior roots more distally, creating the appearance of exaggerated root divergence between the canine and the first premolar. For the mandibular teeth, the images projected almost all roots more mesially than they really were, with the canine and the first premolar the most severely affected. The largest angular difference for adjacent teeth occurred between the mandibular lateral incisor and the canine, with relative root parallelism projected as root convergence. It was concluded that the clinical assessment of mesiodistal tooth angulation with panoramic radiography should be approached with extreme caution and with an understanding of the inherent image distortions.  相似文献   
87.
Abstract This study evaluated a bioresorbable barrier with and without decalcified freeze-dried bone allograft (DFDBA) in the treatment of human molar furcations. 14 subjects with paired class II mandibular molar furcation defects participated in the study (8 male and 6 female). The class-II furcation defects were randomly treated with either the resorbable barrier alone or resorbable barrier in combination with decalcified freeze-dried bone allograft (DFDBA). Gingival recession, probing depth, clinical attachment, and bone fill were measured. 6 months post-treatment measurements were repeated and each site was surgically re-entered. When the resorbable barrier alone was compared to resorbable barrier in combination with DFDBA. probing depth reduction was significantly (p<0.01) in favor of the combination therapy. Vertical bone gain was significant with the combination treatment demonstrating more bone fill (p<0.02). Smoking was also a variable examined in this study. When compared to smokers, non-smokers for both treatment groups revealed greater probing depth reduction, vertical bone gain, and horizontal bone gain. Within the non-smoking group, probing depth reduction was also significantly higher for the resorbable barrier and DFDBA group than the resorbable alone group (p<0.02). These results illustrate that the probing depth reduction is better in the non-smoker and the best in the non-smoker with the combination therapy of resorbable barrier and DFDBA than with resorbable barrier alone.  相似文献   
88.
Christensen GJ  Child P 《Dentistry today》2011,30(2):134, 136, 138 passim
If you were to buy all of the technologies that are currently advertised as being important, it would be financially stressful. In addition, you may not find that you would use all of them with equal enthusiasm. In our opinion, some new technologies are mandatory for current practice, while others are primarily elective. Only you can decide which technology is desirable to better treat your patients and make dentistry more enjoyable for you and your staff. Incorporation of the right new technology into your practice will excite you, your staff, and your patients, stimulate your interest in dentistry, and potentially provide higher quality dentistry. The money you spend on the technology of your choice will be well spent if you evaluate each concept carefully and thoroughly before buying it.  相似文献   
89.
PURPOSE: To develop a pilot in vitro accelerated laboratory testing protocol for assessing marginal sealing capability of dental adhesives. METHODS: Occlusal cavities were prepared in 20 human molar teeth and restored with Spectrum TPH resin composite. Prime & Bond NT and Prompt L-Pop served as the adhesive for eight teeth each. An experimental self-etching adhesive system was used on the remaining four teeth. Each specimen was subjected in sequential fashion to the following challenges: 400,000 wear cycles in a Leinfelder simulator; 5000 thermocycles between water baths maintained at 5 degrees C and 55 degrees C with a dwell time of 40 seconds in each; and a repetition of the 400,000 wear cycles. Polyvinyl siloxane impressions were made at baseline and after each challenge. Microleakage was assessed following silver nitrate staining and marginal degradation was evaluated using light microscopy and the stone casts made from the impressions taken during the project. RESULTS: Microleakage analysis yielded the following median leakage values: Prime & Bond NT - 0; Prompt L-Pop - 1; and experimental self-etching adhesive - 3. The Wilcoxon sign rank test demonstrated significant differences between all three adhesives (P < or = 0.05). Evaluation of the stone casts demonstrated that marginal gaps were more prevalent after the second wear challenge.  相似文献   
90.
The metabolic response to injury is well described; however, very little is understood about optimal markers to measure this response. This summary will address the current evidence about monitoring nutritional status including blood glucose after acute brain injury (ABI). An electronic literature search was conducted for English language articles describing the testing, utility, and optimal methods to measure nutritional status and blood glucose levels in the neurocritical care population. A total of 45 articles were included in this review. Providing adequate and timely nutritional support can help improve outcome after ABI. However, the optimal content and total nutrition requirements remain unclear. In addition, how best to monitor the nutritional status in ABI is still being elucidated, and at present, there is no validated optimal method to monitor the global response to nutritional support on a day-to-day basis in ABI patients. Nitrogen balance may be monitored to assess the adequacy of caloric intake as it relates to protein energy metabolism, but indirect calorimetry, anthropometric measurement, or serum biomarker requires further validation. The adverse effects of hyperglycemia in ABI are well described, and data indicate that blood glucose should be carefully controlled in critically ill patients. However, the optimal frequency or duration for blood glucose monitoring after ABI remains poorly defined. There are significant knowledge gaps about monitoring nutritional status and response to nutritional interventions in ABI; these need to be addressed and hence few recommendations can be made. The optimal frequency and duration of blood glucose monitoring need further study.  相似文献   
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