Addition of ammonium-based methacrylates to an experimental dental adhesive for bonding metal brackets: Carious lesion development and bond strength after cariogenic challenge.

INTRODUCTION: In this study, we evaluated the caries inhibition and shear bond strength achieved with the addition of the antibacterial monomer [2-(Methacryloyloxy)ethyl] trimethylammonium chloride (MADQUAT) to an adhesive used to bond orthodontic brackets. METHODS: Experimental adhesives were formulated with addition of 0% (control), 5%, or 10% MADQUAT followed by measurement of the degree of conversion. These adhesives were used to lute brackets to the enamel of premolars (n = 30). Biofilm from a microcosm model was cultivated in half of the specimens under cariogenic challenge for 5 days. The brackets were subjected to a shear bond strength test followed by measurement of the internal hardness of the enamel around the brackets to calculate the integrated mineral loss. RESULTS: The addition of MADQUAT slightly increased the degree of conversion. Adhesive containing 10% MADQUAT significantly reduced the integrated mineral loss around the bracket but also resulted in the lowest values of bond strength. No effects on bond strength and integrated mineral loss were observed with the addition of 5% MADQUAT to the adhesive. The cariogenic challenge did not affect the bond strength and the failure mode. CONCLUSIONS: MADQUAT was effective to reduce the integrated mineral loss only when added to the adhesive at a concentration of 10% despite the reduction of bond strength.

Fluoride-Releasing Materials to Prevent White Spot Lesions around Orthodontic Brackets: A Systematic Review.

The relation between orthodontic fixed appliances use and enamel demineralization is well established. Different preventive approaches have been suggested to this problem, but controversy remains about which is the best. The aim of this study was to perform a systematic review of clinical trials that investigated the effectiveness of materials containing fluorides to lute brackets or cover the bonding interface in order to inhibit the development and progression of white spot lesions. The null hypothesis was that fluoride materials do not affect the incidence of white spot lesions around brackets. A MEDLINE search was conducted for randomized clinical trials evaluating the development of white spot lesions in patients using fixed orthodontic appliances, followed by meta-analysis comparing the results for patients for whom dental materials containing fluorides were used (experimental group) to those for whom these materials were not used (control group). The pooled relative risk of developing white spot lesions for the experimental group was 0.42 (95% confidence interval: 0.25 to 0.72); hence, when fluoride-releasing materials are used, the patient has 58% less risk of white spot lesion development. Regarding white spot lesion extent, the pooled mean difference between the experimental and control groups was not statistically significant (-0.12; 95% confidence interval: -0.29 to 0.04). In conclusion, the results of the present systematic review suggest that fluoride-releasing materials can reduce the risk of white spot lesions around brackets. However, when white spot lesions had already occurred, there is no evidence that fluoride-releasing materials reduce the extent of these lesions.

Fluoride-Releasing Materials to Prevent White Spot Lesions around Orthodontic Brackets: A Systematic Review

Abstract The relation between orthodontic fixed appliances use and enamel demineralization is well established. Different preventive approaches have been suggested to this problem, but controversy remains about which is the best. The aim of this study was to perform a systematic review of clinical trials that investigated the effectiveness of materials containing fluorides to lute brackets or cover the bonding interface in order to inhibit the development and progression of white spot lesions. The null hypothesis was that fluoride materials do not affect the incidence of white spot lesions around brackets. A MEDLINE search was conducted for randomized clinical trials evaluating the development of white spot lesions in patients using fixed orthodontic appliances, followed by meta-analysis comparing the results for patients for whom dental materials containing fluorides were used (experimental group) to those for whom these materials were not used (control group). The pooled relative risk of developing white spot lesions for the experimental group was 0.42 (95% confidence interval: 0.25 to 0.72); hence, when fluoride-releasing materials are used, the patient has 58% less risk of white spot lesion development. Regarding white spot lesion extent, the pooled mean difference between the experimental and control groups was not statistically significant (-0.12; 95% confidence interval: -0.29 to 0.04). In conclusion, the results of the present systematic review suggest that fluoride-releasing materials can reduce the risk of white spot lesions around brackets. However, when white spot lesions had already occurred, there is no evidence that fluoride-releasing materials reduce the extent of these lesions.

Resumo A relação entre o uso de aparelhos ortodônticos fixos e desmineralização do esmalte é bem estabelecida. Diferentes abordagens preventivas têm sido sugeridas para este problema, mas ainda permanece controverso qual é o melhor. O objetivo deste estudo foi realizar uma revisão sistemática de ensaios clínicos que investigaram a efetividade de materiais contendo fluoretos para cimentação de bráquetes ou cobrindo a interface de união buscando inibir o desenvolvimento e progressão de lesões de mancha branca. A hipótese nula foi que materiais fluoretados não afetam a incidência de lesões de mancha branca em volta de bráquetes. Uma busca no MEDLINE foi conduzida para ensaios clínicos controlados avaliando o desenvolvimento de lesões de mancha branca em pacientes usando aparelhos ortodônticos fixos, seguido por meta-análise comparando os resultados de pacientes em que materiais usando fluoretos foram utilizados (grupo experimental) com aqueles em que tais materiais não foram usados. O risco relativo agrupado de desenvolvimento de lesões de mancha branca para o grupo experimental foi 0,42 (95% de intervalo de confiança: 0,25 a 0,72); enquanto que, quando materiais liberando fluoretos foram utilizados, o paciente teve 58% menos risco de desenvolver lesões de mancha branca. Em relação à extensão das lesões de mancha branca, a diferença média agrupada entre os grupos experimental e controle não foi estatisticamente significante (-0,12; 95% de intervalo de confiança: -0,29 a 0,04). Em conclusão, os resultados da presente revisão sistemática sugerem que materiais que liberam fluoretos podem reduzir o risco de lesões de mancha branca em volta de bráquetes. Entretanto, quando lesões de mancha branca já ocorreram, não há evidência que materiais que liberam fluoretos reduzem a extensão da lesão.