Revista de Odontologia da UNESP
https://revodontolunesp.com.br/article/588018a67f8c9d0a098b4d54
Revista de Odontologia da UNESP
Original Article

Influência da morfologia da junção amelocementária (JAC) nas alterações de pH extrarradicular associadas ao clareamento intracoronário

Influence of cementoenamel junction morphology (CEJ) on the extraradicular pH alterations associated with intracoronal bleaching

Bernardineli, Norberti; Bodanezi, Augusto; Bramante, Clovis Monteiro; Garcia, Roberto Brandão; Moraes, Ivaldo Gomes de

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Abstract

Este estudo longitudinal investigou o efeito da ausência de junção amelocementária (JAC) na variação de pH extrarradicular durante clareamento interno. Dividiram-se 30 incisivos humanos extraídos em dois grupos experimentais (n = 12) e um grupo controle (n = 6). Nos espécimes do grupo experimental I, as junções amelocementárias foram mantidas intactas; no grupo experimental II, as mesmas foram completamente removidas por desgaste com ponta diamantada antes da inserção intracoronária de peróxido de hidrogênio a 30% (Magistral Pharma). No grupo controle, as câmaras pulpares foram repletas de soro fisiológico. Em cada intervalo experimental de 0, 24, 72, 96, 156, 192 e 270 horas, mensurava-se o pH extrarradicular por meio da sonda de um peagômetro (Micronal®) inserida na água destilada em que os espécimes eram imersos e, imediatamente, o agente clareador era renovado. A análise de variância a dois critérios revelou para o grupo II (JAC ausente) os menores valores de pH (4,3 ± 0,16), estatisticamente diferentes do grupo controle (7,1 ± 0,20) nos intervalos de 156, 192 e 270 horas, e do grupo I (5,9 ± 0,14) no período de 270 horas (p ≤ 0,05). Concluiu-se que a ausência de união entre cemento e esmalte intensificou a redução de pH no meio extrarradicular somente após 270 horas de clareamento interno.

Keywords

Colo do dente, clareamento de dente, peróxido de hidrogênio, reabsorção de dente.

Resumo

This longitudinal study investigated the effect of cementoenamel junction (CEJ) absence on the extraradicular pH variation during intracoronal bleaching. Thirty extracted human incisors were divided into two experimental groups (n=12) and a control (n=6). In specimens of group I the cementoenamel junctions were kept original whereas in group II they were completely removed through cut using a diamond bur prior the intracoronal insertion of 30% hydrogen peroxide (Magistral Pharma). For the control group the pulp chambers were filled with saline. In the experimental intervals of 0, 24, 72, 96, 156, 192 and 270 hours the extraradicular pH was measured by means of a pH meter (Micronal®) probe inserted in the distilled water in which the specimens were immersed, and soon afterwards the bleaching agent was renewed. The two-way analysis of variance revealed the lowest pH levels for group II (4,3±0,16) which were statistically different from that of control group (7,1±0,20), at the intervals of 156, 192 and 270 hours, and from that of group I (5,9±0,14) at 270 hours (p≤0.05). It was concluded that the absence of cementoenamel junction intensified the extraradicular decrease of pH only after 270 hours of intracoronal bleaching.

Palavras-chave

Cementoenamel junction, tooth bleaching, hydrogen peroxide, tooth resorption

References



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