Assessing push‐out bond strength in re‐irradiated teeth: Universal resin cement performance in self‐etch and self‐adhesive modes
Gabriel Hernandez Machado de Souza, Luiz Carlos de Lima Dias‐Junior, Renata Gondo Machado, Gabriela Pasqualin Ghidini, Mariana Comparotto Minamisako, Marcio Toshio Umeda Takashima, Nayara Cardoso Cábia, Ricardo Machado, Cleonice da Silveira Teixeira, Lucas da Fonseca Roberti Garcia- General Dentistry
Abstract
Objectives
To investigate the effect of cumulative doses of radiation on the pushout bond strength (BS) of a universal resin cement used in the self‐etch (SE) and self‐adhesive (SA) modes to the intraradicular dentin.
Materials and Methods
Forty‐eight human teeth were distributed into three groups (n = 16) according to the radiation therapy dose (RT): NoRT (no‐radiotherapy), 70RT (70 Gy), and 70 + 70RT (70 Gy + 70 Gy). The teeth were redistributed into two subgroups (n = 8), according to the adhesive mode: SE (NoRT‐SE, 70RT‐SE, and 70 + 70RT‐SE) and SA (NoRT‐SA, 70RT‐SA, and 70 + 70RT‐SA). Data were statistically compared after BS test (ANOVA, Tukey's post hoc test, and Fisher's exact test).
Results
In the SA mode, BS was significantly higher in nonirradiated teeth compared with 70RT and 70 + 70RT (p < 0.0001). There were no significant differences between SE and SA modes in nonirradiated teeth (p = 0.14). In the 70RT group, SE mode increased BS compared with SA mode (p < 0.0001). Most specimens had adhesive and mixed failures in SA and SE modes, respectively.
Conclusions
The universal resin cement in the SE mode had greater BS to the irradiated dentin. When teeth were re‐irradiated, the universal resin cement had similar performance in terms of BS, regardless of the adhesive approach.
Clinical Significance
There is no research establishing a correlation between radiotherapy and its impact on the BS of a universal resin cement used in SE and SA modes to intraradicular dentin.