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81.

Objective

The placement of orthodontic bands usually increases plaque accumulation due to numerous mechanical retention sites. The purpose of this investigation was to evaluate the amount and distribution pattern of biofilm in the oral (palatal and lingual) and interproximal regions surrounding orthodontic bands.

Materials and Methods

We evaluated the formation of biofilm on 32 orthodontic bands which had been placed intraorally for 6?C37?months. Two parameters were measured: the percentage of surface covered by biofilm (quantity) and the biofilm distribution pattern of accumulation. We measured these two parameters in four regions of interest: the mesial and distal interproximal regions, as well as the mesial and distal regions of the oral attachment.

Results

The quantity of biofilm formation was similar in all four regions of interest, ranging from 13.3% to 16.8%. In contrast to biofilm quantity, distribution patterns differed in the four regions. In the mesial and distal interproximal regions it appeared as extensive insular areas in 87.5% and 71.9%, respectively, whereas it appeared more often supragingival and linear in nature in regions adjacent to the oral attachment, i.e. in 65.6% and 68.8%, respectively.

Conclusion

Our results indicate that firstly, oral hygiene in the palatal and lingual regions of orthodontic bands seems as difficult as it is in the interproximal areas, thus requiring thorough hygiene in both areas. Secondly, orthodontic patients with a history of periodontal disease require special attention regarding the use of orthodontic bands.  相似文献   
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Low-dose methotrexate (MTX) is frequently used for patients with rheumatoid arthritis (RA). High doses of MTX frequently produce side effects. The aim of this study was to explore oral complications of low-dose MTX therapy in a population of RA patients. This is a cross-sectional study in which oral examination was performed on a population of RA patients. Patients undergoing MTX therapy (5-20 mg weekly) for at least six months were included in the study group, and RA patients being treated under another regimen were used as controls. The frequency of oral lesions was compared between groups. The chi-square test was used to compare frequencies. Relative risk (RR) and its confidence interval (CI) were established. Significance level was set at 0.05. Twenty-eight RA patients on a low-dose MTX regimen and 21 controls were enrolled in the study. Oral lesions were found in 22 patients (78.6%) undergoing MTX therapy, and in 5 patients (23.8%) undergoing other therapies (p < 0.001). There were no significant differences regarding age, gender or dosage. The most common oral events observed in patients in the MTX group were ulcerative/erosive lesions (60.7%) and candidiasis (10.7%). Patients in the control group presented lower prevalence of the same lesions (p < 0.001). The RR for developing oral lesions was 11.73 (CI 2.57 - 58.98), with low-dose MTX therapy. In conclusion, the prevalence of oral mucosa lesions in RA patients receiving low doses of MTX therapy is higher than in RA patients not receiving the drug.  相似文献   
84.
The aims of this study were to demonstrate the synthesis of an experimental glass ionomer cement (GIC) by the non-hydrolytic sol-gel method and to evaluate its biocompatibility in comparison to a conventional glass ionomer cement (Vidrion R). Four polyethylene tubes containing the tested cements were implanted in the dorsal region of 15 rats, as follows: GI - experimental GIC and GII - conventional GIC. The external tube walls was considered the control group (CG). The rats were sacrificed 7, 21 and 42 days after implant placement for histopathological analysis. A four-point (I-IV) scoring system was used to graduate the inflammatory reaction. Regarding the experimental GIC sintherization, thermogravimetric and x-ray diffraction analysis demonstrated vitreous material formation at 110oC by the sol-gel method. For biocompatibility test, results showed a moderate chronic inflammatory reaction for GI (III), severe for GII (IV) and mild for CG (II) at 7 days. After 21 days, GI presented a mild reaction (II); GII, moderate (III) and CG, mild (II). At 42 days, GI showed a mild/absent inflammatory reaction (II to I), similar to GII (II to I). CG presented absence of chronic inflammatory reaction (I). It was concluded that the experimental GIC presented mild/absent tissue reaction after 42 days, being biocompatible when tested in the connective tissue of rats.  相似文献   
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Introduction

Regenerative endodontic procedures have emerged as a new treatment. The aim of this case report was to describe a regenerative autologous cellular therapy using mesenchymal stem cells from inflamed dental pulp and leukocyte platelet-rich fibrin (L-PRF) in a mature tooth.

Methods

A healthy 50-year-old man consulting for spontaneous dental pain was referred for endodontic treatment in tooth #28, which was diagnosed with symptomatic irreversible pulpitis. Inflamed dental pulp was extracted and transported to a good manufacturing practice laboratory for the isolation and culture of dental pulp stem cells (DPSCs). L-PRF was obtained from the patient's blood and was introduced into the instrumented and disinfected root canal, and expanded DPSCs were inoculated into the clot. The cervical part of the root canal was sealed with Biodentine (Septodont, Saint-Maur-des-Fosses, France) and a composite resin.

Results

Follow-up examinations were performed 6 months and 3 years later. The examinations included periapical radiographs (to measure the periapical index [PAI]), cone-beam computed tomographic (CBCT) imaging, sensitivity, and vitality tests. Clinical evaluations revealed normal responses to percussion and palpation tests. The tooth had a delayed response to cold, and the electric pulp test was responsive. The PAI and CBCT imaging revealed that the periapical area remained normal with a PAI score of 1 and a CBCT PAI score of 0. The vitality test performed indicated low blood perfusion units.

Conclusions

This case study reveals the potential use of a patient's own DPSCs and L-PRF as an alternative procedure for the treatment of pulpitis in mature permanent teeth. It also paves the way for the design of personalized cell-based clinical trials in regenerative endodontics.  相似文献   
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90.
Esthetic dental procedures in pediatric dentistry represent sources of satisfaction and realization, as much for the patient as for the professional. Lack of dental esthetics may develop psychological problems in infant as well as in adolescent patients. Blemishes produced by fluorosis appear as a challenge to the pediatric dentist and alternatives for treatment are desired. The scope of this present paper is to relate a clinical case with esthetic solution for blemishes in teeth enamel due to fluorosis. A dual system of bleaching was used (photo/chemically activated) based on hydrogen peroxide at 35% (Hi-Lite-Shofu) in a male eight-year-old patient with white fluorosis blemishes on teeth 11 and 21. The bleaching system used was efficient in bleaching teeth with white blemishes due to fluorosis, thus masking the blemishes and providing a more uniform appearance.  相似文献   
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