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61.
An inadequate fit at the abutment/implant interface can generate mechanical and biological problems. The laboratorial stages could induce misfit in such interface when the castable UCLA abutment type is used. The purpose of this study was to comparatively evaluate the performance of three prosthetic laboratories (Labs A, B and C) by vertical fit analysis of castable UCLA abutments on the casting and soldering stages of the same prosthesis. Four fixed prostheses were built by each laboratory using castable UCLA abutments. The evaluation was made by scanning electron microscopy under 500x magnification in the mesial and distal regions of each element of the prosthesis, totalizing 24 measurements per laboratory. The results were analyzed statistically by Kruskal-Wallis test (p<0.05). In the casting process, the values presented by the laboratories differed significantly to each other (p=0.004). After soldering, the values presented by the laboratories showed no significant difference (p=0.948). It may be concluded that the fit values obtained in the casting stage of UCLA abutments can be influenced when processed by different laboratories, and that conventional soldering itself increased the degree of framework misfit, regardless of which laboratory made it.  相似文献   
62.
Peripheral cemento-ossifying fibroma is a gingival lesion of reactive nature and unknown etiology. Such a lesion can either interfere with normal tooth eruption or become a factor in plaque development, which usually results in caries formation in newly erupted teeth. Therefore, the objective of the present article was to report a case of peripheral cemento ossifying fibroma occurring in the mandibular posterior region of a 11-year-old girl in association with both absence of premolar eruption and presence of severely caried first permanent molar.  相似文献   
63.

Objective

The aim of this study was to determine the salivary levels of dehydroepiandrosterone (DHEA) and cortisol and scores of depression, anxiety and stress in patients with oral lichen planus (OLP).

Study design

Thirty-one patients with a diagnosis of OLP were selected; they were matched by sex and age with 31 control patients. Symptoms of depression, anxiety and stress were investigated by the instruments Beck Depression Inventory, Beck Anxiety Inventory and Lipp's Inventory of Stress Symptoms for Adults, respectively. Saliva was collected in the morning and at night for the determination of DHEA and cortisol levels by radioimmunoassay.

Results

There was no significant difference between the groups with respect to depression (P = 0.832), anxiety (P = 0.061) or stress (P = 0.611), or with respect to morning and night salivary levels of DHEA (P = 0.888, P = 0.297) and cortisol (P = 0.443, P = 0.983).

Conclusions

The results suggest an association of OLP with anxiety. However, DHEA and cortisol levels did not differ between groups, which does not support any neuroendocrine aetiology for OLP.  相似文献   
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The aim of this study was evaluate the dimensional stability of some condensation silicones. The following materials were studied: Coltex/Coltoflax - Coltène, Speedex - Coltène, and Optosil Comfort/Xantopren VL Plus - Kulzer. They were evaluated by dimensional analysis and gas chromatography (GC) performed at the following times: T0, T1, T2, T3, T4, and T5 (immediately after setting, thirty minutes, two hours, twenty four hours, seventy two hours, and seven days after setting, respectively). The dimensional changes were measured directly in the molds using a Mitutoyo microscope. The Coltex fine/Coltoflax and Optosil Comfort/Xantopren VL Plus materials presented dimensional stability for up to thirty minutes after molding, while the Speedex material remained stable for up to two hours after molding. The gas chromatography experiment demonstrated that these materials release ethanol even after clinical setting.  相似文献   
68.
Background: The present study aims to compare the performance of minimally invasive non‐surgical and surgical approaches for the therapy of intrabony defects. Methods: Twenty‐nine patients who presented with intrabony defects were randomly assigned to: 1) a minimally invasive non‐surgical technique (MINST) group, or 2) minimally invasive surgical technique (MIST) group. The chair time of each therapeutic procedure was calculated. The probing depth (PD), position of the gingival margin (PGM) and relative clinical attachment level (RCAL) were evaluated at 3 and 6 months after treatments. The patient perception of discomfort/pain experienced during and after therapy and patient satisfaction regarding treatments were also evaluated. Results: Significant PD reductions, RCAL gains, and no changes in the PGM were obtained at 3 and 6 months in MINST and MIST groups (P <0.05). No differences were observed between groups at any time points (P >0.05). Patient‐oriented outcomes did not demonstrate differences between therapeutic approaches (P >0.05). Significant higher chair times were required in the MIST group than in the MINST group (P <0.05). Conclusions: Minimally invasive non‐surgical and surgical approaches were successfully used for the treatment of intrabony defects and achieved periodontal health in association with negligible morbidity and suitable patient satisfaction. However, non‐surgical therapeutic modality presented an advantage in terms of a reduction of treatment chair time.  相似文献   
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Objective

Actinic cheilitis (AC) is a precancerous lesion of the lip vermillion caused by prolonged exposure to ultraviolet light. The aim of this study was to evaluate the effect of 3% diclofenac in 2.5% hyaluronic acid gel in the treatment of AC.

Methods

Thirty-four patients with chronic AC were treated twice a day with topical diclofenac during a period of 30 to 180 days. The individuals were followed up every 15 days by means of clinical examination and digital photographic documentation.

Results

Of the 27 patients that completed the study, 12 (44%) showed complete remission of the whitish plaques and exfoliative areas, and 15 (56%) had partial remission of the clinical picture of cheilitis. The latter group was submitted to excision of the leukoplakic areas which diagnosis varied from mild to moderate epithelial dysplasia.

Conclusion

The results suggest a promising role for diclofenac in hyaluronic acid gel in the treatment of AC. This treatment has the advantages of not being invasive and showing few side effects.  相似文献   
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