Er: YAG laser debonding performance for cement-retained zirconia implant crowns
摘要
Erbium laser debonding methods have been increasingly applied in natural tooth restorations and are highly important for the repair and maintenance of cement-retained implant restorations. However, the debonding process is challenging, and research on its safety, efficacy, and influencing factors remains insufficient. Therefore, this study aimed to investigate the effects of different zirconia crowns and abutments on temperature increases and debonding time when using an Er: YAG laser to debond zirconia cement-retained implant crowns.
MethodsThe different abutments and zirconia crowns were divided into four groups, the Ti-3Y, Ti-4Y/5Y, Zir-3Y, and Zir-4Y/5Y groups, with 8 zirconia crowns in each group. An Er: YAG laser was used to remove the crowns. The average and maximum temperature increases at three points, the abutment region (∆T1, ∆T1 MAX), middle of the implant (∆T2, ∆T2 MAX), and apical region of the implant (∆T3, ∆T3 MAX)) were measured using a thermocouple thermometer and calculations. The debonding time was also recorded. One crown from each group was randomly selected to evaluate the surface morphology with scanning electron microscopy (SEM). Data were analysed by one-way analysis of variance (ANOVA).
ResultsAll 32 zirconia crowns were successfully removed using the Er: YAG laser. With the same abutment, the ∆T1 MAX in the 3Y groups was lower than that in the 4Y/5Y groups. Compared with the 4Y/5Y groups, the 3Y groups required more time for the removal procedure (p < 0.05). With the same zirconia crown materials, the ∆T1 MAX in the Ti groups was lower than that in the Zir groups (p > 0.05), and the removal time in the Ti groups was shorter than that in the Zir groups (p > 0.05). SEM examinations did not reveal any signs of microcracks in the zirconia crowns.
ConclusionThe Er: YAG laser debonding method can be used to successfully remove cement-retained zirconia implant crowns, and the temperature increase and debonding time are affected by the type of zirconia crown but not the type of abutment.