Tooth color alteration after debonding in orthodontic patients with adhesive removal using composite bur or tungsten carbide bur: a single center, randomized controlled clinical trial / Alteração da cor do dente após descolagem de braquetes em pacientes ortodônticos pela remoção de adesivo usando broca de compósito ou broca carbide de tungstênio: ensaio clínico unicêntrico randomizado e controlado

Objective: The objective of this study was to determine whether recently developed fiber reinforced composite burs provided better results by comparing tooth discoloration after debonding of orthodontic brackets. Material and Methods: A split-mouth, randomized controlled trial was carried out in one orthodontic office; including 23 patients with intact, vital and caries-free four upper incisors aged 12 to 30 years who completed their fixed orthodontic treatment. For each patient, upper central and lateral incisors on each side of the mouth were randomly selected to remove the adhesive with either a tungsten carbide bur (TC) (n = 46) or a fiber-reinforced composite bur (FC) (n=46). Color evaluation of each tooth was conducted at two time points: immediately after finishing and polishing procedure and two months afterwards. The primary outcome would be the amount of color change in each group during the post treatment phase. The participants, the person assessing the color change and the statistician were blinded to TC group assignment. Color changes in each group were analyzed with the Paired T-test. The color change corresponding to the resin removal method was also statistically analyzed with the Independent T-test at α=0.05 as the level of significance. Results: 86 teeth, 43 in each group, were analyzed. The ΔE value was 3.713±1.161, for teeth finished TC and 2.114±0.514 for teeth finished with FC (p<0.01). Conclusion: Adhesive removal with FC bur results in a more color-resistant tooth surface in comparison with tungsten carbide bur. (AU)

Objetivo: O objetivo deste estudo foi determinar se as brocas de material compósito reforçadas com fibras, recentemente desenvolvidas, proporcionam melhores resultados, pela comparação da descoloração dentária após a remoção de braquetes ortodônticos. Material e Métodos: Um ensaio clínico controlado randomizado com boca dividida foi realizado em um consultório ortodôntico, incluindo 23 pacientes, com idade entre 12 e 30 anos, com incisivos superiores intactos, vitais e livres de cárie, que completaram o tratamento ortodôntico com aparelho fixo. Para cada paciente, incisivos centrais e laterais superiores de cada lado da boca foram selecionados aleatoriamente para remover o adesivo ortodôntico com uma broca carbide de tungstênio (TC) (n = 46) ou uma broca de compósito reforçada com fibra (FC) (n = 46). A avaliação da cor de cada dente foi realizada em dois momentos: imediatamente após o acabamento e polimento e dois meses após. O resultado primário foi a quantidade de mudança de cor em cada grupo durante a fase pós-tratamento. Os participantes, a pessoa que avaliou a mudança de cor e o estatístico não tinham conhecimento da atribuição ao grupo TC. As mudanças de cor em cada grupo foram analisadas com o teste-t pareado. A mudança de cor correspondente ao método de remoção da resina também foi analisada estatisticamente com o teste-t independente considerando um nível de significância α = 0,05. Resultados: foram analisados 86 dentes, 43 em cada grupo. O valor de ΔE foi 3,713 ± 1,161, para dentes finalizados com broca TC e 2,114 ± 0,514 para dentes finalizados com broca FC (p <0,01). Conclusão: A remoção do adesivo com broca FC resulta em uma superfície de dente mais resistente à cor em comparação com a broca carbide de tungstênio (AU)

The effect of remin pro and MI paste plus on bleached enamel surface roughness.

OBJECTIVE: Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin. MATERIALS AND METHODS: Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM. RESULTS: The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05). There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected. CONCLUSION: Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.