Longevity of posterior restorations in primary teeth: results from a paediatric dental clinic.

OBJECTIVES: The aim of this retrospective study was to evaluate the longevity of restorations in the posterior primary teeth of children attending to a public paediatric dental clinic and to test the factors associated with failures. METHODS: Patient records of 329 children (162 boys and 166 girls) were used for collecting and analyzing data. A total of 565 restorations in primary teeth were included in the study. All children enrolled in the study were classified as high caries risk. The longevity of restorations from their placement until failure (up to 4 years of follow-up) was assessed using the Kaplan-Meier survival curves with log-rank test. Multivariate Cox regression analysis with shared frailty (p<0.05) was used to assess the factors associated with failures. RESULTS: Up to 4 years of follow-up, the annual failure rates were 9.5% for composite fillings, 12.2% for light-cured glass ionomer restorations, and 12.9% for conventional glass ionomer restorations with statistical difference between the materials (p=0.014). Glass ionomer restorations had a higher risk of failure over time compared with composites (HR 1.86, 95% CI 1.17-2.97). In crude analysis, Class II restorations showed lower survival rate than Class I restorations (p=0.031) but lost significance after adjustments. CONCLUSIONS: Our findings suggested that the material influenced the survival rate of primary posterior restorations, with composite presenting the best performance. CLINICAL SIGNIFICANCE: Differences were observed between restorative materials with different properties in primary teeth up to 4 years of follow-up. This study provides valuable information regarding the primary teeth posterior restoration longevity in a paediatric population with restorations performed under daily life clinical environment.

Estudo das inclinações axiais mesiodistais em pacientes tratados pela técnica Straight Wire / Study of mesiodistal axial inclinations in patients treated with the technique Straight Wire

As angulações dentárias corretas são condições fundamentais para se obter um equilíbrio na oclusão. O objetivo deste trabalho foi avaliar as inclinações axiais mesiodistais de pacientes tratados ortodonticamente utilizando radiografias panorâmicas comparando a fase inicial com a fase final e esta última com os valores médios normais propostos na literatura. A amostra constou de 120 radiografias panorâmicas (60 na fase inicial e 60 na fase final) de pacientes tratados ortodonticamente pela técnica Straigth-Wire, sendo 30 do gênero feminino e 30 do gênero masculino. Mensuraram-se todos os dentes, exceto segundos e terceiros molares. Os dados foram analisados estatisticamente pelo teste t de Student para amostra pareada e Wilcoxon para os dados que não apresentavam distribuição normal. Os resultados encontrados mostraram uma diferença significante entre as inclinações axiais mesiodistais dos grupos iniciais e finais em vários elementos dentais, exceto dos dentes 23, 33, 32, 42, 43 e 44, sendo que estes valores foram sempre maiores ao final do tratamento e observadas diferenças estatisticamente significantes (p<0,05). Quando se comparou as inclinações axiais mesiodistais do grupo "final" com aquelas obtidas na literatura, houve diferenças significantes para todos os elementos dentais à exceção do dente 11, sendo os valores obtidos neste estudo foram menores tanto para a arcada inferior quanto superior .

The correct dental angulations are fundamental requisites in order to obtain an occlusion balance. This paper aimed to evaluate mesiodistal axial inclinations of orthodontically treated patients by means of panoramic radiographies comparing the initial to the final phase, and the latter to the normal mean values proposed by literature. The sample was made up of 120 panoramic radiographies from patients being orthodontically treated by the Straigth-Wire technique, 60 of which in the initialphase, and the other 60 in the final one. Each phase consisted of 30 male and 30female patients. All teeth except 2nd and 3rd molars were measured up. The data obtained were statistically analyzed by the T Student test for paired sampling and by Wilcoxon for data that did not present normal distribution. The results showed a significant difference among the mesiodistal axial inclinations from the initial and final groups in many dental elements, except for teeth 23, 32, 33, 42, 43 and 44. All values were always higher towards the end of treatment and statistically significantdifferences were found (p < 0,05). When the mesiodistal axial inclinations of the final group were compared to those obtained by literature, there were significant differences for all dental elements except tooth 11 and the values obtained by this study were smaller for both upper and lower arcade .