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91.
OBJECTIVE: The purpose of this study was to investigate the effects of low power red laser associated with acidulated phosphate fluoride on the development of induced-dental caries in rats. DESIGN: Dental caries were induced in molars of 40 rats divided into five groups: control group (CG), the teeth were not submitted to any treatment; laser group (LG), teeth were irradiated with a low power red laser (LPRL), power of 30 mW and dose of 5 J/cm(2); fluoride group (FG), teeth were treated with topical acidulated phosphate fluoride (APF) 1.23% applied for 4 min; laser+fluoride group (LFG), teeth were irradiated with LPRL followed by APF; fluoride+laser group (FLG), teeth were treated with APF followed by LPRL. The animals were killed after 48 days, and the first and second molars were extracted to analyze the caries lesion area, microhardness, and calcium and phosphorus ratio. RESULTS: There were no statistical differences among FG, LFG, and FLG regarding to caries area and microhardness, although the caries area were smaller in LFG. Ca/P ratio did not show significant differences among all groups. CONCLUSIONS: Although LPRL before APF application appeared to diminish the caries progression, LPRL did not present any additional benefit compared with acidulated phosphate fluoride on the prevention of induced-dental caries in rats.  相似文献   
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AIM: To investigate in individuals with symptomatic dental abscesses the occurrence of functional polymorphisms within five genes involved with the immune response. The functional gene polymorphisms analysed were CD14 (-260 C/T), IL1B (+3954 C/T), IL6 (-174 G/C,), IL10 (-1082 G/A) and TNFA (-308 G/A). METHODOLOGY: Genomic DNA obtained from oral swabs from individuals with symptomatic dental abscesses and asymptomatic inflammatory periapical lesions, without previous exacerbation, was submitted to restriction fragment length polymorphism (RFLP) analyses to determine each individual genotype. The chi-square and principal components analysis tests were used for statistical analysis. RESULTS: A significant association was observed between the occurrence of the GG genotype or the G allele expression of the polymorphic locus-174 (G/C) of the IL6 gene, and the presence of the symptomatic dental abscesses in women and in individuals < or =35 years old. The principal components analysis suggested predominance of the symptomatic dental abscesses in individuals displaying: high-producer IL6 genotype; intermediate and high-producer IL1B genotypes and low-producer TNFA genotype. CONCLUSIONS: The present study suggests that genetic factors are associated with susceptibility to develop symptomatic dental abscesses.  相似文献   
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The following case report describes the management of a 6-year-old male patient in early mixed dentition with a mesial step molar relation, an anterior reverse overjet, and skeletal Class III due to a slightly deficient maxilla. The treatment plan included protraction of the maxilla by a reverse pull Petit type facemask for 10 months followed by 15 months of active retention by a Frankel III appliance.  相似文献   
95.
Bisphosphonate induced osteonecrosis of the jaw (BONJ) is a complication in patients taking bisphosphonate (BP) that affects their quality of life and compliance. In this cohort study, patients with multiple myeloma (MM) on intravenous BP therapy were enrolled over 1 year. Demographic and clinical data and genotyping of 10 single nucleotide polymorphisms (SNPs) from seven candidate genes associated with drug or bone metabolism were determined. Of the 78 patients enrolled, 12 had BONJ. The median time to developing BONJ was 28 months. Univariate and multivariate analysis revealed a significant association between BONJ and smoking (p = 0.048) and type of BP treatment (p = 0.03). A trend for higher odds for BONJ was found for SNPs in five genes: COL1A1 (rs1800012), RANK (rs12458117), MMP2 (rs243865), OPG (rs2073618) and OPN (rs11730582). Considering all five SNPs together, patients with genotype scores ≥5 had a BONJ event rate of 57%; those with scores <5 had a rate of 10%. The adjusted odds ratio was 11.2 (95% confidence interval of 1.8-69.9; p value 0.0097). Smoking, type of BP and combined genotype score of COL1A1, RANK, MMP2, OPG and OPN were significantly associated with BONJ in MM patients undergoing BP therapy.  相似文献   
96.
Orthognathic surgery in patients with osteogenesis imperfecta is rare. Most cases result in a successful outcome with stable and good occlusion. Two patients with, probably severe types III and IV, and malocclusion class III with retrognathic maxilla and prognathic mandible, were treated with orthodontic treatment and bimaxillary surgical correction. The surgical outcome and follow up are presented together with a review of published cases of orthognathic surgery in patients with different types of osteogenesis imperfecta. The authors conclude that it is possible to perform combined orthodontic and orthognathic surgery in patients with osteogenesis imperfecta despite the greater risk of complications. The treatments were successful with follow up times of 5-6 years.  相似文献   
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