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991.
992.
Accumulation of dental plaque for 3 and 7 days respectively was determined by calculating the difference between the postcollection and precollection weights of enamel slabs attached to orthodontic bands cemented to the upper first molars of 3 subjects. Pretreatment of the enamel slabs with amine-fluoride or -chloride respectively-at an equivalent amine concentration-prevented plaque deposition on the slabs, whereas pretreatment with sodium monofluorophosphate was less effective. The fluoride concentrations of all fluoride-pretreated enamel slabs were similar. No convincing demonstration of significant differences between the treatments could be predicted in view of the discrepancy in results at the 3- and 7-day test periods.  相似文献   
993.
A low molecular weight (9600) glycoprotein was isolated from monkey (Macaca arctoides) extra-parotid saliva by gel filtration on Sephadex G-200 and Sephadex G-50. Criteria of purity included immunodiffusion, immunoelectrophoresis and polyacrylamide gel electrophoresis. The molecule contained 76 per cent protein, 23.4 per cent carbohydrate and 0.6 per cent phosphorus. The glycoprotein was a potent inhibitor of calcium phosphate precipitation.  相似文献   
994.
995.
996.
The planning of dental implant position and its transfer to the operation site can be considered as one of the most important factors for the long-term success of implant-supported prosthetic and epithetic restorations. This study compares computer-assisted fabricated surgical templates as the static method with intro-operative image guided navigation as the dynamic method for transfer of three-dimensional pre-operative planning. For the static method, the systems Med3D, coDiagnostix/ gonyX, and SimPlant were used. For the dynamic method, the systems RoboDent und VectorVision2 were applied. A total of 746 implants were inserted between August 1999 and December 2005 in 206 patients. The static approach was used most frequently, accounting for 611 fixtures in 168 patients. The failure ratios within the first 6 months were 1.31% in the statically controlled insertion group compared to 2.96% in the dynamically controlled insertion group. Complications related to an incorrect position of the implants have not been observed so far in either group. All computer-assisted methods included in this study were successfully applied in a clinical setting after a certain start-up period. The indications for application of computer-assisted methods in implantology are currently given in difficult anatomical situations. Due to uncomplicated handling and low resource demands, the static template technique can be recommended as the method of choice for the majority of all cases falling into this category.  相似文献   
997.

Objectives:

this study evaluated the apical deviation of curved root canals instrumented with K3 and ProTaper systems.

Material and methods:

twenty root canals of human maxillary and mandibular first molars were employed, which were divided into 2 groups: group A (10 teeth) was instrumented with the K3 system, and group B (10 teeth) with the ProTaper system. Evaluation of deviation was performed by double radiographic exposure. Radiographs were achieved before and after instrumentation, with 0.3-second, thus allowing superimposition of images. Three-dimensional computerized tomograph was performed in 3 specimens in each group, as an additional means to evaluate the apical deviation.

Results:

were evaluated by the parametric test Student-Newman-Keuls at 5%, which did not reveal significance between groups concerning the apical deviation. The results of computerized tomograph images demonstrated that the larger deviation of the root canal occurred at the distolingual area for both systems.

Conclusions:

both techniques produced a mild apical deviation. Computerized microtomography was shown to be accurate for experimental endodontics studies.  相似文献   
998.
PURPOSE: This cross-sectional study evaluated the relationship between attrition and diverse variables in 390 Mexican adolescents aged 14 to 19 years. MATERIALS AND METHODS: An ordinal scoring system was used to describe the severity of attrition. RESULTS: Attrition prevalence was 33.3% and was associated with older age, presence of defective restorations, Class II malocclusion, and perception of stress level. CONCLUSION: Our results suggest that attrition is present in 1 of every 3 adolescents.  相似文献   
999.
Salivary glands are sites for a great variety of tumors. The parotid gland is the most common site followed by the submandibular gland. The pleomorphic adenoma represents the 60-70% of all tumors involving the major salivary glands, while the submandibular gland is involved in 8% of cases. The pleomorphic adenoma of the submandibular gland is rare and can present difficulty in diagnosis. The heterogeneous histology, a possible malignant transformation, an incomplete capsule that can determine a recurrence, are the most important characteristics of pleomorphic adenoma. A complete surgical removal of the tumor is the treatment of choice. In the case presented, the mass showed an unusual vascularization and remarkable dimensions.  相似文献   
1000.
OBJECTIVE: To report a newborn with van der Woude syndrome, Pierre Robin sequence, and oral synechiae. Pierre Robin sequence is a rare manifestation of van der Woude syndrome as are oral synechiae. We speculate that the oral synechiae may be causally related to the development of Pierre Robin sequence in this patient.  相似文献   
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