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31.
BACKGROUND: The aim of this study was to compare the response to conventional periodontal treatment between patients with or without type 2 diabetes mellitus from a clinical and metabolic standpoint. METHODS: A prospective, parallel, comparative longitudinal clinical study was performed between type 2 diabetics and non-diabetics with moderate generalized chronic periodontitis. The study period was 6 months. Conventional periodontal scaling and root planing were performed, and the response to this treatment was compared between the groups at 3 and 6 months, measuring the plaque index, bleeding on probing, probing depth, level of clinical attachment, and gingival recession. In the diabetic patients, the clinical response was related to measurements of HbA1c and glucose in blood at 3 and 6 months. RESULTS: An improvement in all clinical variables was observed, with no statistically significant differences between the groups, with the exception of probing depth (P <0.0207). The improvement observed in blood HbA1c levels confirmed a positive metabolic response to periodontal treatment, with a lower value for this variable at each measurement time. CONCLUSIONS: Both groups of patients showed a clinical improvement after basic non-surgical periodontal treatment. The diabetic patients showed improved metabolic control (lower HbA1c) at 3 and 6 months after periodontal treatment.  相似文献   
32.
OBJECTIVE AND BACKGROUND: Relatively little is known about the epidemiology of necrotizing ulcerative gingival lesions (NUG) in adolescent populations. Most studies have comprised special target groups, such as military recruits, HIV patients, or severely malnourished subjects. METHODS: A multistage random cluster sampling scheme was used to obtain a sample of 9203 students aged 12-21 years from 98 of a total of 618 high schools in Santiago, Chile. Students were given a clinical oral examination and questionnaire information was obtained on smoking and oral hygiene habits, dental attendance patterns, and diabetic status. The diagnostic criteria for NUG were the presence of necrosis and ulceration of at least one interproximal papillae. RESULTS: The estimated prevalence of NUG was 6.7% (95% CI = [6.2; 7.3]). A multivariable logistic regression analysis showed that last seeing a dentist more than 1 year ago (OR = 1.60), or never (OR = 1.93), and reporting diabetes (OR = 2.12) showed a significant positive association with the presence of NUG; whereas neither gender nor smoking were important predictors. Students aged 18-21 years were more, albeit statistically insignificantly, likely to have NUG than were younger students (OR = 1.40). CONCLUSIONS: Our observation that reporting to be diabetic was positively associated with the presence of NUG is interesting, as diabetes has never been addressed as a possible risk factor. As the association between diabetes and periodontitis in adults is thought to relate to impaired function of neutrophils, microangiopathy, and impaired wound healing this finding suggests a significant role of the host response also for the occurrence of NUG.  相似文献   
33.
This study evaluated the predominant microbiota of infected necrotic pulps and the effects of calcium hydroxide therapy on these microorganisms by the checkerboard DNA-DNA hybridization technique. Conventional endodontic therapy associated with calcium hydroxide as intracanal dressing was performed in 12 single-rooted teeth with pulp necrosis and periradicular bone lesion. Samples were collected from the canal at baseline and 14 days after therapy, and the presence of 44 bacterial species was determined by the checkerboard method. Significant differences in the microbiota from baseline to post-therapy were sought by the paired-samples t test. The most prevalent species included F. nucleatum ss. vincentii, C. sputigena, C. ochracea, S. constellatus, V. parvula, P. gingivalis, P. melaninogenica, and S. sanguis. Most of the microorganisms were reduced after treatment, particularly A. gerencseriae, A. israelii, A. naeslundii, C. gingivalis, C. ochracea, P. gingivalis, S. noxia, S. sanguis, and S. oralis (p < 0.05). Conversely, A. actinomycetemcomitans, C. sputigena, and E. corrodens increased in numbers after therapy. These results indicate that conventional endodontic therapy with calcium hydroxide results in the reduction of pathogenic species associated with pulp necrosis. However, its use is limited, because it did not eliminate the whole spectrum of microorganisms.  相似文献   
34.
BACKGROUND: Osteoma is a benign often asymptomatic neoplasm, consisting of well-differentiated mature bone. This paper reports a case of peripheral osteoma located in the anterior mandibular region and provides a review of the literature about this lesion in the jaws. PATIENT AND METHODS: A 43-year-old white woman presented with a swelling in the left mandible of 7 years duration. The English literature was reviewed over the past 76 years and data about location, histopathology and number of the peripheral osteomas, sex, and age of the patients were evaluated. RESULTS: Data analysis showed 69 well-documented cases of peripheral osteoma. Peripheral osteomas are more frequent in the mandible than the maxilla and the cancellous type was most frequent; males and females are equally affected in the mandible; the age range was 9-85 years. CONCLUSION: The peripheral type of osteoma is most common in the lower jaws, occurs at the surface of the cortical bone and is sessile or pedicled.  相似文献   
35.
The purpose of this in vitro study was to compare the marginal leakage in primary molars restored with 2 polyacid-modified composite resins (Dyract AP - Dentsply and F2000 - 3M) and a composite resin (Filtek Z250 - 3M) as control. First and second primary molars were used for preparation of cavities on the proximal surfaces, with extension of the gingival margin to the cementoenamel junction. Restorations were accomplished after total etching and application of the respective adhesive system, and were divided into groups according to the restorative system and the number of adhesive layers used. The teeth were stored in distilled water for 7 days, followed by thermocycling with 500 cycles at 5oC - 55oC, with one minute in each bath. Thereafter, teeth were prepared for immersion in 0.5% methylene blue solution for four hours. The teeth were sectioned in mesiodistal direction for assessment of dye penetration. According to the results of the Kruskal-Wallis test, the three restorative materials employed did not completely avoid marginal leakage at the gingival margin of primary molars. The marginal leakage of PMCR F2000 (4.06 and 3.95) displayed to be higher than the marginal leakage observed for the materials Dyract AP (2.7 and 2.55) and Filtek Z250 (2.25 and 2.43). The number of adhesive layers did not influence the degree of leakage of the three materials.  相似文献   
36.
There are few studies on pediatric oral pathologies in the literature. This study presents data from a review of 2,356 biopsies of young patients (birth to 14 years) received over 15 years (1985-2000) in the Oral Pathology Service at the University of Sao Paulo, Brazil. Information about patients (sex, age, race) and histopathological diagnosis was retrieved. Diagnosis data of 2,356 biopsies were classified into 20 groups. There was no significant difference between male (50.0%) and female (49.0%) patients. White is the predominant race (69.0%), and patients ages were concentrated between 9 and 14 years old (70%). Mucocele was the most frequent (13.5%), followed by dentigerous cyst (6.5%) and fibrous hyperplasia (5.4%). Papilloma and Langerhans cells histiocytosis were the most common non-odontogenic benign and malignant tumors, respectively. In the group of odontogenic tumors, odontoma was the most frequent, and ameloblastoma had a significant incidence (27 cases). These data are important in order to detect differences in geographic areas, diagnosis line tendencies and for clinicians to perform judgment to evaluate of the pediatric patients before the biopsy and management of pediatric oral lesions.  相似文献   
37.
Despite the importance of clonality to understand the pathogenesis and progression of tumors, it has not been investigated yet in giant cell lesions of the jaws. The aim of this study was to analyze the clonality of peripheral giant cell lesions (PGCL) and central giant cell lesions (CGCL) of the jaws. Six samples of PGCL and 5 samples of CGCL were analyzed in this study using the polymorphic human androgen receptor locus (HUMARA) assay. Three out of the 5 samples of the CGCL and 3 out of 6 samples of PGCL exhibited a monoclonal pattern. Our findings demonstrate that some giant cell lesions of the jaws are clonal, which indicate that these lesions may have a common genetic mechanism of development. Further studies are necessary to better elucidate the molecular mechanisms involved in the pathogenesis of such lesions.  相似文献   
38.
The purpose of this study was to compare the castability of Co-Cr-Mo-W (Remanium 2000), Ni-Cr (Durabond) and Co-Cr-Mo (Vera PDI) alloys invested with either conventional (phosphate- and silica-based) or mixed investing techniques. A 10 X 10 mm square-shaped nylon net containing 100 open squares served as a template for construction of wax patterns, which were invested with phosphate-based investment (Termocast), silica-based investment (Refrafil) and mixed investing technique (2-mm layer phosphate investment plus filling with silica investment). Forty-five cast specimens (5 per experimental condition) were obtained and sandblasted with aluminum oxide. The number of completely reproduced cast segments was counted to obtain a percentage designated "castability value", which indicated the accuracy of the alloy to reproduce mold details. Statistical analysis using two-way ANOVA and Tukey's test showed that, comparing the alloys, Remanium 2000 had statistically similar castability (p>0.05) to Vera PDI and lower than Durabond (p<0.05). Considering the mixed technique results, Remanium 2000 yielded lower castability value (p<0.05) than Durabond and Vera PDI alloys, which showed similar results to each other (p>0.05). In conclusion, the castability of the Co-Cr-Mo-W alloy (Remanium 2000) was comparable to that of the Co-Cr alloy (Vera PDI) and worse than that of the Ni-Cr alloy (Durabond). Except for Remanium 2000, the mixed investing technique considerably improved the accuracy of the alloys to reproduce cast details, compared to the phosphate-based investment. The mixed investing technique appears as a viable alternative to improve castability of base metal alloys without decreasing the surface quality of the metallic pieces.  相似文献   
39.
The aim of this study was to evaluate the microbiota and surface of failed titanium dental implants from 4 manufacturers. Twelve mobile dental implants were retrieved from 10 smokers after 3 to 10 years of functional loading. Before implant removal, microbial samples were taken and evaluated using polymerase chain reaction. After implant removal, analyses of the failed implant surfaces were performed using scanning electron microscopy and energy-dispersive spectrometer x-ray. Periodontal pathogens such as Aggregactibacter actinomycetemcomitans, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were detected in all implants in different proportions. Surface analysis showed varying degrees of surface roughness between the samples and the presence of proteinaceous material, appearing mainly as dark stains. Foreign carbon, oxygen, sodium, calcium, aluminum, and silicon elements were also found. Although no material-related causes of implant failure were detected, several periodontal pathogens were identified independently of the surface topography or manufacturer.  相似文献   
40.
Idiopathic osteosclerosis (IO) is described as a localized no expansible radiopacity with unknown etiology. The IO is generally asymptomatic and could appear as round, elliptical or irregular in shape. The internal aspect is usually uniformly radiopaque. IO should be distinguished from condensing osteitis of dental origin, or other alveolar bone related radiopacities such as periapical cemental dysplasia. This condition may cause changes in tooth position or problems during orthodontic treatment. The purpose of the present study is to report a case of tooth resorption caused by ectopic eruption rote caused by IO. This condition represents a rare complication of IO.  相似文献   
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