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51.
PURPOSE: To evaluate the effect of Carisolv solution on the topography and surface hardness of dentin. METHODS: Two separate studies were carried out. Atomic force microscopy (AFM) was employed to visualize dentin surface topography on slices of previously extracted non-carious and carious teeth following the passive application of Carisolv gel for 30- and 60-second periods. A Wallace hardness instrument was used to measure the dentin surface hardness following active caries removal with Carisolv gel and the specially designed instruments. Conventional caries removal with dental burs and non-carious dentin acted as controls for the latter study. RESULTS: AFM revealed that the passive application of Carisolv gel resulted in smoother surfaces than observed on carious and non-carious dentin. There was a statistically significant difference between the mean hardness values for non-carious and Carisolv-treated dentin (P< 0.05). There was no statistically significant difference between the non-carious and bur-treated dentin nor the Carisolv and bur-treated dentin.  相似文献   
52.
Abstract. Drug regimens for transplantation often consist of multiple therapeutic agents and may result in drug-induced gingival overgrowth (DIGO). The aim of this study was to investigate the contribution of individual drugs in renal transplant patients. 147 adults (19–84 years) and 60 juveniles (3–18 years) were scored for DIGO and other clinical variables. Duration of treatment, dosage of drugs per kg body weight and serum cyclosporin levels were recorded. 44% of adults and 27% of children had DIGO. All patients were receiving prednisolone. More adults than children were administered cyclosporin, the reverse was true of azathioprine ( P 0.01), Explanatory models were evaluated by stepwise ordinal polynomial logistic regression. Statistically significant explanation ( P 0.05) of DIGO was afforded by prednisolone, nifedipine and azathioprine concentrations in adults and by cyclosporin, nifedipine and azathioprine concentrations in juveniles. Prednisolone and azathioprine were inversely related to the degree of DIGO. Plaque and irregularity scores, lip coverage and mouthbreathing status showed significant additional explanation in adults, replacing nifedipine and azathioprine in the final model. Irregularity was additionally explanatory in children, but no other clinical variables. A larger proportion of the variance of DIGO was explained by the available variables in children than in adults (pseudo r 2=0.50 versus 0.25). The degree of DIGO in renal transplant patients is influenced by the dosage of a number of individual components of multiple drug therapy independently of the presence of local clinical factors.  相似文献   
53.
Attitudes to glove wearing by dentists practising within the NHS Regulations were tested by means of a questionnaire distributed to 2000 dentists in England and Wales. The response was 76.5%. The results indicate that 68% of the respondents wore gloves routinely for all patients and procedures, 3% never wore gloves, while the remainder (29%) wore gloves for only selected patients or selected procedures. Reasons given for not wearing gloves routinely included problems of comfort, loss of tactile sensation and the risk of cross-infection, which was perceived to be small. Of the routine glove wearers, only 12% changed gloves between patients, cost being considered to be a factor by 57% of respondents who used gloves for more than one patient. The results indicate that the respondents practising and personal details had an influence on the pattern of glove wearing, with single-handed practitioners and those who graduated before 1979 being less likely to wear gloves routinely. Comparison with the findings of earlier studies of similar type suggest that there is increased awareness in the dental profession of the necessity for glove wearing, but that there is still a need to encourage routine glove use, especially amongst certain groups of GDPs.  相似文献   
54.
The continuous search for improved surgical procedures to address gingival deformities is a consequence of an increasing demand for aesthetics in the periodontal clinical practice. Innovative techniques have been reported to help clinicians achieve predictability in root coverage. Significant progress can be attributed to the inclusion of the operative microscope in periodontal therapy, particularly in regards to obtaining primary closure. This article describes a microsurgical technique used to treat gingival recessions, showing its potential for obtaining optimal aesthetic results.  相似文献   
55.
BACKGROUND: The subgingival microflora in patients presenting concurrently with periodontitis and diabetes mellitus (DM) are poorly understood. While traditional putative periodontal pathogens are implicated, research involving other oral organisms; e.g., Capnocytophaga spp., is lacking. These organisms produce a range of bacterial enzymes relevant to periodontal breakdown. It is inferred that periodontal bacteria acquire systemic access through the ulcerated periodontal pocket surface; conclusive evidence supporting this notion is limited. The aims of this investigation were to: 1) quantify and identify Capnocytophaga spp. present in healthy and diseased sites in periodontitis patients with and without DM, and 2) isolate periodontal pathogens from these patients' blood. METHODS: Twenty-one DM-periodontitis and 25 periodontitis patients were recruited. Subgingival plaque was collected from three healthy and three diseased sites per subject. Capnocytophaga spp. and total (facultative and obligate) anaerobic counts from each site were estimated. Capnocytophaga spp. were identified using 16S rRNA polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). Statistical analyses were performed using multilevel modeling. Blood samples were subjected to HbA(1c) estimation and bacterial culture. RESULTS: A total of 848 Capnocytophaga spp. were isolated and identified. Significantly higher numbers of Capnocytophaga spp. (P <0.001) and anaerobes (P <0.001) were present in diseased sites in DM-periodontitis subjects compared to healthy sites in non-DM-periodontitis and DM-periodontitis subjects. C. ochracea (and variant) and C. granulosa were the most prevalent species. Blood samples were negative for Capnocytophaga spp. CONCLUSIONS: Total mean counts for Capnocytophaga spp. were significantly higher in DM-periodontitis subjects versus non-DM-periodontitis (P = 0.025) and at diseased sites versus healthy sites (P <0.001). Analysis of individual species revealed that the outcome varied with site status and DM status.  相似文献   
56.
This paper reports on changes in mandibular condylar growth in sheep fitted with experimental functional appliances. The paper also addresses the similarities of mandibular condylar growth in sheep and humans. Experimental functional appliances were developed, constructed and applied to four, four-month old, male sheep. Another four sheep served as matched controls. All animals received fluorochrome bone labels during the study and their weight gain also was recorded. Fifteen weeks later, all animals were sacrificed and each temporo-mandibular joint and left metacarpus were removed. Undecalcified mid-sagittal sections of the joint and metacarpus were prepared for fluorescence microscopy. The mandibular condylar growth vector in sheep was found to be in a postero-superior direction. Condylar growth in the control sheep during the experimental period varied from 8.8 to 11.9 mm, with the mean being 10.6 mm, which is quantitatively similar to two years of condylar growth in human adolescents. In the experimental sheep, the condylar growth varied from 8.5 to 13.3 mm, with the mean being 11.4 mm. When metacarpal growth and weight gain were taken into consideration using multivariant analysis, the coefficients for growth in the postero-superior and posterior direction were found to be high, with adjusted r2 as 0.84 and 0.82 respectively. The induced condylar growth was estimated to be largest in the posterior direction (2.30 mm), which is also similar to previous reports in humans. These findings suggest the appropriateness of using sheep as a model for quantitative histological analysis when investigating the mechanisms of functional appliance treatment.  相似文献   
57.
The objective of this study was to investigate the histometric impact of nicotine on bone regeneration of surgically created alveolar ridge defects in dogs. Sixteen mongrel dogs were used. One defect was surgically created unilaterally in the mandible, and left to heal spontaneously. The animals were randomly assigned to one of the following groups: Group 1--control (n = 8) and Group 2--subcutaneous nicotine administration (2 mg/kg) twice a day (n = 8). After 4 months, the animals were sacrificed and the specimens routinely processed for semi-serial decalcified sections. Bone height (BH), bone width (BW), bone density (BD), and bone area (BA) of the newly-formed bone were evaluated. Intergroup analysis (Mann-Whitney rank sum test) showed that regardless of the presence of nicotine, no significant differences were observed regarding bone width (BW), bone area (BA) and bone height (BH) (p > 0.05). On the other hand, it was demonstrated that nicotine administration significantly influenced the proportion of mineralized tissue within the limits of the newly-formed bone (BD) (p < 0.001). Within the limits of the present study, it can be concluded that nicotine might affect but not prevent bone healing in defects left to heal spontaneously.  相似文献   
58.
In an era of self-directed learning, it is important to seek the views of dental students regarding their learning experience. Using an anonymous questionnaire, clinical dental students' perceptions of seminar and lecture-based teaching in restorative dentistry were sought. 116 of 136 questionnaires circulated were returned for analysis giving a response rate of 85%. Clinical seminars as opposed to lectures were, in the opinion of the students, a more effective way of learning, more relevant to self-development and more interactive. Seminar-based learning was considered to be more amenable to self-direction than formal didactic lectures. It is concluded that the students included in this study were found to prefer seminar-based learning opportunities as opposed to more traditional styles of learning, specifically, didactic lectures.  相似文献   
59.
Tooth loss in maintenance patients in a private periodontal practice   总被引:2,自引:0,他引:2  
A group of 162 maintenance patients, previously studied for compliance to suggested maintenance schedules, were surveyed for tooth loss over a 5-year period. The group was divided into those who complied to suggested maintenance schedules and those whose compliance was erratic. It was found that none of the patients who had complied to suggested maintenance schedules lost any teeth. In the erratic group, where all tooth loss occurred, it was found that the more often a patient presented for maintenance, the less likely he was to lose teeth. These findings are discussed in relation to current studies on efficacy of various therapies for periodontal diseases.  相似文献   
60.
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