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41.
The adenomatoid odontogenic tumour of the jaws is rare. It is important to differentiate it from other odontogenic tumours because of its benign behaviour and this can be reliably done by the histological features.  相似文献   
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43.
During the cementation of metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. This study evaluated the influence of chemical activation compared with dual-curing (chemical and light activation), on the hardness of four dual-curing resin cements. In a darkened environment, equal weight proportions of base and catalyst pastes of the cements Scotchbond Resin Cement, Variolink II, Enforce and Panavia F were mixed and inserted into moulds with cavities of 4 mm in diameter and 2 mm in height. Subsequently, the cements were: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated (dual-curing = dual-cured groups). The Vickers hardness number was measured at 1 hour, 24 hours and 7 days after the start time of cements' spatulation. For all the cements, the hardness values of self-cured groups were lower than those of the respective dual-cured groups at 1 hour and 24 hours. At 7 days, this behavior continued for Variolink II and Panavia F, whilst for Scotchbond Resin Cement and Enforce there was no statistical difference between the two activation modes. All cements showed a significant increase in their hardness values from 1 hour to 7 days for both activation modes. Of the self-cured groups, Scotchbond Resin Cement and Variolink II presented the highest and the lowest hardness values, respectively, for all three times tested. Within the limitations of this study, up to the time of 24 h, chemical activation alone was unable to promote similar hardness as to that obtained with dual-curing.  相似文献   
44.

Objective:

To evaluate the role of socioeconomic variables and self-perceived oral health in the polarization of caries among adolescents in Santa Bárbara D''Oeste, Brazil.

Material and Methods:

Cross-sectional study. Sampling was randomized and sample size was defined according to WHO criteria. Two hundred and seventy seven adolescents (15 to 18 year-old) were examined by five trained examiners that assessed DMFT index according to WHO criteria. Self-perceived oral health, access to dental services and socio-demographic variables were self-reported. Student''s t tests, chi-square tests, and multivariate logistic regression (with significant caries index (SiC) as the outcome), were performed.

Results:

Mean DMFT was 5.48 (±4.22) and the proportion of "caries free" subjects was 15.5%. Mean DMFT (9.71±2.85) and mean D (1.67±2.18) of SiC positive subjects were significantly higher than mean DMFT (2.88±2.17) and mean D (0.45±0.87) of SiC negative subjects (p<0.0001). Mean D of white (0.76±1.51) was significantly smaller than mean D of non-white subjects (1.32±2.01). The only variable independently associated with the "SiC positive" outcome was "report of toothache within six months prior to the study" [OR=1.83 (95%CI 1.08 to 3.12)], p<0.001.

Conclusion:

SiC was associated with "report of toothache" but not with sociodemographic variables in the studied population.  相似文献   
45.
AIM: To evaluate the incidence of disease recurrence following a full-mouth pocket/root debridement approach with ultrasonic instrumentation versus that following a traditional approach of quadrant-wise scaling and root planing (Q-SRP) performed with hand instrumentation. METHODS: Thirty-seven patients were re-examined 1 year after the completion of a 6-month clinical trial comparing two different treatment protocols: a 1-h session of full-mouth ultrasonic debridement (UD--19 patients) or four sessions of Q-SRP with hand instruments (Q-SRP--18 patients). At 3 months, re-instrumentation was performed of pockets showing a remaining probing pocket depth (PPD) of > or =5 mm using the same type of instruments as used during the initial treatment phase. The clinical examinations comprised assessments of plaque, bleeding on probing (BoP) and PPD. The primary outcome variable was the incidence of recurrent diseased sites (i.e., sites showing PPD > or =5 mm and BoP+) between the post-treatment and 1-year follow-up examinations. All sites that were healed (PPD < or =4 mm and BoP(-)) at the post-treatment examination were included in the study sample, with a mean number of sites per patient of 23.5. RESULTS: In the UD group, 29 (7%) out of 430 initially healed sites showed disease recurrence at the 1-year follow-up examination compared with 47 (11%) of 440 sites in the Q-SRP group (p>0.05). Twelve patients (63%) in the UD group presented recurrent diseased pockets, compared with 14 patients (78%) in the Q-SRP group. Two or more recurrent, diseased pockets were observed in nine patients in the UD group versus 11 in the Q-SRP group. All but one of the smokers belonged to the group of patients presenting recurrences. A tendency towards a higher mean plaque score was observed for the patients with recurrent sites. CONCLUSION: The study revealed no significant difference in the incidence of recurrence of diseased periodontal pockets between the full-mouth UD approach and the traditional approach of Q-SRP.  相似文献   
46.
Abstract – This article reports a longitudinal follow‐up of a 15‐month‐old child with dental trauma resulting from an attack by a dog. The injury consisted of laceration of the facial tissues and loss of the upper central deciduous incisors, in addition to loss of bone tissue in the same area. A malformation of the crown of the right central permanent incisor and complete change of the shape of the left central permanent incisor were observed. The etiological factors of childhood injuries as well as the importance of dental emergency care are discussed and the 14‐year clinical and radiographic follow up of the case is presented.  相似文献   
47.
PURPOSE: The purposes of this prospective multicenter study were to evaluate the use of vertical distraction osteogenesis in the correction of vertically deficient alveolar ridges and to evaluate whether the vertical bone gained by distraction osteogenesis was maintained over time when dental implants were placed in the distracted areas. MATERIALS AND METHODS: Thirty-seven patients presenting vertically deficient edentulous ridges were treated in 4 different centers by means of distraction osteogenesis with an intraoral alveolar distractor. Two to 3 months after consolidation of the distracted segments, 138 dental implants were placed in the distracted areas. Four to 6 months later, abutments were connected and prosthetic loading of the implants began. RESULTS: The mean follow-up after initial prosthetic loading was 34 months (range 15 to 55 months). The mean bone gain obtained by distraction was 9.9 mm (range 4 to 15 mm). The cumulative success rate of the implants 4 years after the onset of prosthetic loading was 94.2%, while the implants' cumulative survival rate was 100%. No statistically significant differences were found between the different centers as far as survival and success rates of implants were concerned. DISCUSSION AND CONCLUSION: The results of this study appear to demonstrate that distraction osteogenesis is a reliable technique for the correction of vertically deficient edentulous ridges. The regenerated bone appeared to withstand the functional demands of implant loading. The survival and success rates of the implants placed in the distracted areas were consistent with those reported in the literature regarding implants placed in native bone in this patient population.  相似文献   
48.
49.
Objectives: This study aimed to assess whether and to what extent the experimental gingivitis clinical parameters are reproducible within selected populations with different gingival inflammatory response (high or low) to plaque accumulation. In addition, the consistency in developing a high or low gingival inflammatory response within the selected populations was evaluated. Material and Methods: Thirty‐seven subjects previously identified as high (HR, n=20) or low responders (LR, n=17) during an experimental gingivitis trial (first trial) were enrolled in a “repeat” experimental gingivitis trial. Results: No significant differences in plaque accumulation parameters and bleeding index values were detected between first and repeat trial for the 37 participants. Gingival index was higher during the repeat trial but behaved consistently in terms of the temporal changes in the course of both trials in both populations. Of the 17 LR participants, 10 manifested low susceptibility to inflammation after repeat trial. Among the 20 HR, 10 manifested high susceptibility to inflammation after repeat trial. Conclusions: These results indicate that our experimental gingivitis model is reproducible to some extent in selected populations. The high reproducibility of plaque and, to a lesser extent, of inflammation parameters under the employed controlled conditions could be a valuable tool in gingivitis research.  相似文献   
50.
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