Vânia Regina Camargo Fontanella

CT evaluation of apical canal transportation associated with stainless steel hand files, oscillatory technique and ProTaper rotary system

This study used computed tomography (CT) to compare apical canal transportation in mesiobuccal canals of maxillary molars prepared with different techniques. Sixty teeth were assigned to 3 groups (n=20), according to the technique used for root canal instrumentation: hand instrumentation with K-Flexofiles, K-Flexofiles activated by an oscillatory system and ProTaper NiTi rotary system. Pre and post-instrumentation CT images were obtained 3 mm short of the apical foramen and were superimposed to compare canal transportation. Data were analyzed statistically by ANOVA and Tukeys test using the SPSS software (α=0.05). In the buccal direction, the manual technique produced significantly less canal transportation than the oscillatory technique (p<0.05) and both were similar to the rotary technique (p>0.05). In the distal and distopalatal directions, the oscillatory technique produced more canal transportation (p<0.05). In the mesiopalatal direction, the oscillatory technique produced more canal transportation than the manual technique (p<0.05), and both were similar to the rotary technique (p>0.05). In conclusion, all techniques produced canal transportation, and the oscillatory technique produced the greatest removal of root dentin toward the innerside of the root curvature.

Evaluation of optical density of bone defects filled with calcium phosphate cement and bioactive glass in rats

PURPOSE To evaluate new bone formation, by the analysis of optical density, in rat femoral defects filled with calcium phosphate cement (CPC) and bioactive glass (BG). METHODS Twenty-one rats were divided into three groups, Group I (CPC), Group II (BG), and Group III (control), and assessed after 7, 15, and 30 days. Three bone cavities were made in the left femur and filled with CPC, BG, and no material (control). Digital images were obtained and the results were subjected to statistical analysis of variance (ANOVA), complemented by the Friedman and Kruskal-Wallis nonparametric tests, with a significance level of 5%. RESULTS Regarding optical density, Group I showed statistical values significantly higher than Group III and also higher, although not statistically significant, than Group II, in all observation periods. When Groups II and III were compared, Group II showed higher optical density values, without statistically significant differences, in all periods. CONCLUSION The biomaterials analyzed showed higher optical density in relation to the control group in all observation periods, calcium phosphate cement being the best option in the repair of bone defects, but without statistically significant differences in relation to bioactive glass.

Comparison of different methods involved in the planning of clinical crown lengthening surgery

There is little material in the literature that compares biological width measurements in periapical and bite-wings radiographs with clinical measurements. The purpose of this study was to compare measurements of biological width taken by three different methods which are frequently used for planning periodontal surgery - periapical radiograph, bite-wing radiograph and transperiodontal probing - with the trans-surgical measurements. Thirty-four sites from twenty-one subjects were analyzed. The intra-class correlation coefficients between measurements obtained trans-surgically (gold standard) and those obtained by transperiodontal probing, periapical radiography and bite-wing radiography were determined. Average measurements were compared using the Wilcoxon test at a significance level of 0.05. Also, the frequency distribution of differences between test measurements and the gold standard was calculated. The results showed that transperiodontal probing (mean 2.05 mm) was the most accurate measurement, as compared to the gold standard (mean 1.97 mm), with no statistically significant difference observed. On the other hand, periapical and bite-wing radiographic mean values (1.56 mm and 1.72 mm, respectively) were smaller than the gold standard, with statistically significant differences (p < 0.05). It was concluded that transperiodontal probing was the most accurate measurement, as compared to the gold standard, followed by that obtained with the bite-wing radiograph. The clinical relevance of these results could be that planning for crown lengthening surgery should, preferably, include transperiodontal probing.

Wylie-Johnson analysis of adolescents of Afro-Brazilian descent with normal occlusion: investigation of the mean values

OBJECTIVE: The purpose of this study was to evaluate mean cephalometric measurements for a group of individuals of Afro-Brazilian descent using the Wylie-Johnson analysis, and to investigate the presence of sexual dimorphism.METHODS: Thirty-six lateral radiographs of the head of African-Brazilians were used. Subjects were 10 to 14 years old and had clinically normal occlusion, all permanent teeth, and no history of orthodontic treatment.RESULTS: Results for girls and boys were, respectively: SNA 88.31o and 89.68o; SNB 83.96o and 85.01o; ANB 4.44o and 4.69o; 1:1= 118.18o and 116.51o; FG-ST 16.47 mm and 16.12 mm; ST-Pmf 19.69 mm and 19.88 mm; Pmf-ANS 53.69 mm and 54.84 mm; Pmf-1oMS 21.83 mm and 20.64 mm; FG-Pg 108.19 mm and 108.45 mm; FPL -MPL 27.48o and 27.65o; TAFH 111.06 mm and 112.26 mm; UAFH 45.26 mm and 45.38 mm; LAFH 65.80 mm and 66.88 mm; FG-FPL 1.069 mm and -2.086 mm; MBL 70.24 mm and 69.67 mm; MRH 51.89 mm and 53.70 mm; gonial angle 129.27o and 129.28o. Results of Students-t test (α=5%) did not show any sexual dimorphism. Results of descriptive statistics were similar for the individuals of Afro-Brazilian descent in the study.CONCLUSION: Individuals of African descent had bimaxillary protrusion, a more acute interincisal angle, a larger inferior facial height, and a markedly convex profile.