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991.
Two cases of fibrous defect (nonossifying fibroma) of the mandible are presented. Each case occurred in the mandibular ramus of an 11-year-old girl. The usual fibrous defect of bone is an intraosseous fibrous, nonneoplastic, reactive lesion which appears as a well-delineated defect in the metaphysis of long bones. This report reviews the literature, histopathology, and classification of the fibrous defect of bone.  相似文献   
992.
This article describes a method for constructing composite slides without destroying the original slide. A conventional slide projector, rear-projector screen, modified 35 mm camera, and slide-duplicating film are required for this technique.  相似文献   
993.
BACKGROUND: The authors investigated mouthrinses' antimicrobial effectiveness against predominant oral bacteria, as determined by the minimum inhibitory concentration (MIC). Specifically, they evaluated an herbal mouthrinse, an essential oil rinse and a 0.12 percent chlorhexidine gluconate rinse. METHODS: The authors assessed the inhibitory effects of the three test agents against 40 oral bacteria at concentrations of 1, 2, 4, 8, 16, 32, 64, 128, 256 and 512 micrograms per millliter. They inoculated plates containing basal medium and the test agents with suspensions of the test species and incubated them anaerobically at 35 degrees C. The authors interpreted the MIC as the lowest concentration of the agent that completely inhibited the growth of the test species. RESULTS: The herbal mouthrinse inhibited the growth of most of the 40 test species. Compared with the essential oil mouthrinse, the herbal mouthrinse exhibited significantly lower MICs for Actinomyces species, periodontal pathogens Eubacterium nodatum, Tannerella forsythia and Prevotella species, as well as the cariogenic pathogen Streptococcus mutans. The chlorhexidine gluconate rinse had the lowest MICs compared with the essential oil rinse and the herbal rinse for all test species examined. CONCLUSIONS: Although less potent than the chlorhexidine gluconate rinse, the herbal rinse was more effective than the essential oil rinse in inhibiting the growth of oral bacteria in vitro. CLINICAL IMPLICATIONS: The data suggest that the herbal mouthrinse may provide oral health benefits by inhibiting the growth of periodontal and cariogenic pathogens. In vivo clinical testing is essential to confirm in vitro results.  相似文献   
994.
The kinematic center (KC)-defined by coinciding jaw-opening/-closing and protrusion-retrusion trajectories-has been proposed in the literature as a reference point to represent TMJ movements. In this study, we tested whether the KC lies in a peculiar anatomical point and whether its trajectory reflects intra-articular distance. In 11 asymptomatic individuals (seven females, four males, aged 24-37 yrs), 4 openings/closings and 4 protrusions/retrusions were tracked with dynamic stereometry. In a 3D lattice (0.5 mm grid) constructed solidly around each condyle, the KC was the point with maximal cross-correlation between opening-closing and protrusion-retrusion paths. KC trajectories were more cranial on closing than on opening, consistent with intra-articular distances being smaller on closing than on opening. However, KCs were never located on condylar main axes (distance, 4.5 +/- 2.9 mm), nor did they coincide with points best approximating fossa shapes (distance, 12.5 +/- 6.4 mm). The kinematic center's anatomical and functional significance therefore appears to be questionable.  相似文献   
995.
996.
AIM: The aim of this study was to compare the clinical and microbiological healing outcomes following non-surgical periodontal therapy using the new Vector ultrasonic system versus scaling and root planing (S/RP) with Gracey curettes. MATERIAL AND METHODS: The study comprised 20 chronic periodontitis patients. Using a split-mouth design, both treatment modalities were randomly applied to one quadrant of the upper and the lower jaws each. Clinical and microbiological parameters were assessed at baseline, 4 weeks, and 6 months after treatment. Furthermore, post-operative hypersensitivity was assessed. The Wilcoxon signed rank test (alpha=0.05) was used for statistical analysis. RESULTS: Both therapies provided statistically significant clinical and microbiological improvements of periodontal conditions after 4 weeks and 6 months. Hypersensitive teeth were found only 4 weeks after S/RP. Besides a significantly better bleeding on probing reduction in deep S/RP sites, no other clinical and microbiological parameters revealed significant differences between the sites treated with the Vector system or S/RP. CONCLUSION: Both the Vector system and S/RP provided favourable periodontal healing results, although in deep pockets S/RP appeared to achieve a better resolution of inflammation.  相似文献   
997.
W S J Holtshousen  A Smit 《SADJ》2007,62(8):334, 336-338, 340
During 1997, the Gauteng Oral Health Services implemented a Mobile Oral Health Care System (MOHCS) in the province. For the first year (1997/98) one mobile dental clinic was utilised in the West Rand region of the province and services were provided by dentists, dental therapists and oral hygienists. The purpose of the MOHCS is to provide an accessible and affordable comprehensive oral health care service of high quality and standard. The aim of this study was to determine the cost-efficiency of the mobile dental clinic utilised in the West Rand region over the first year of implementation. After consultation with all stakeholders, an operational plan was finalised. The plan included a traveling schedule, clinicians available for service delivery, and a management information system (MIS). Statistics on dental materials, consumables, treatment provided, etc. were collected and analysed. During the study period 2072 patients received dental treatment at 38 different sites in the region. At an average cost of R56.50 (+/- US$11) per patient, services to the value of R92.45 (+/- US$18) per patient were delivered during 104 working days. Of the 1477 patients treated by a dentist or dental therapist, 53% were treated by extracting 1026 teeth, and 27% by restoring 570 teeth. For oral hygiene patients, 67% received an oral hygiene procedure and 13% received fissure sealants. With a net margin ratio of 0,39 and a breakeven point of 1173,46 patients and 58,90 days, an accessible and cost-efficient service was provided to health districts in the West Rand region.  相似文献   
998.

Introduction

Ten to twelve percent of all cases of maxillary sinusitis derive from odontogenic origin. The purpose of this study was to report the use of cone-beam computed tomography (CBCT) scanning in elucidating dental pathology as an etiology of maxillary sinusitis.

Methods

Intraoral periapical radiographs and CBCT scanning were performed in the evaluation of three patients presenting with pain, sinus congestion, or respiratory complaints. In the first case, extractions of impacted third molar and adjacent nonrestorable tooth were performed. In the second two cases, endodontic therapy was done. Radiologic follow-up with CBCT scanning or medical computed tomography scanning was performed 6 to 12 months after dental procedures were performed.

Results

All three patients presented with severe sinusitis that resolved after appropriate dental treatment. The first patient also showed marked improvement of chronic bronchitis after completion of dental treatment. In all patients, complete or near total resolution of sinusitis, including eradication of mucous retention cyst, was confirmed by post-treatment CBCT or computed tomography scanning.

Conclusions

These cases show the utility of CBCT scanning in evaluating patients presenting with concurrent sinus and dental complaints. In these three patients, maxillary sinusitis of odontogenic origin responded well to the eradication of dental etiology.  相似文献   
999.
Background: Government subsidized dental care is provided as a community safety‐net to complement the private dental sector. The aim of this study was to detail the geographic catchment characteristics of three outer metropolitan government dental clinics. Methods: Three outer metropolitan dental clinics with the greatest number of geocoded triage patients were selected for the study. In total these three facilities had 5742 patients over the 12‐week period with 2010 at clinic A, 1278 at clinic B and 2454 at clinic C. Cumulative proportions of patients’ residential address locations at distances were calculated; there was close correlation between the three clinics. A best fit curve with a correlation coefficient of 0.998 was developed. Results: In summary, approximately 50% of patients were within 6 km of the clinic and 75% were within 10 km. Conclusions: This study has critical outcomes for the planning of future services in developing a network model for care. The data presented will assist in the development of more evidence‐based approaches to planning new service network structures.  相似文献   
1000.
There has been growing interest in the use of virtual learning environments (VLEs) by universities over the past decade to supplement traditional teaching methods. In this study a tutorial providing information about the temporomandibular joint (TMJ), temporomandibular disorders and teaching of a thorough TMJ examination was developed on a VLE platform to enable students to enhance their examination and diagnostic skills. The success of this VLE tutorial was compared with conventional teaching by a cross-over trial. Thirty students were initially randomly allocated to one of two groups; Group 1 completed the VLE tutorial and Group 2 attended the face-to-face seminar in the first instance. The groups then crossed over and had the other method of teaching provided. The findings from the cross-over trial and the students' feedback indicated that no differences were found between either teaching modes, and both are equally effective at delivering information to students. In addition, the order in which the students received the teaching did not make a difference, but giving the teaching twice reinforced their knowledge. There is a strong case to be made for introducing clinical lectures on a VLE platform, and this form of e-learning is, in general, well perceived by new generations of students.  相似文献   
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