Assessment of microtensile bond strength of different caries removal techniques with ICDAS scores

Abstract

This study aimed to evaluate the effect of different caries removal techniques and ICDAS scoring to microtensile bond strength (µTBS). Fourty-eight human molars assessed clinically and having scores of 0, 3, 4 and 5 based on Interna�onal Caries Detec�on and Assessment System (ICDAS) criteria were inspected. Group ICDAS 0 taken as control for microtensile test. Each group was divided into 4 groups as 1 complete caries removal (CCR) and 3 selec�ve caries removal (SCR) methods: these are stainlesssteel round bur (SSRB), ceramic round bur (CRB), tungsten carbide round bur (TCRB) & bioac�ve glass powder (BAG), TCRB & 29 µm Al2O3, respec�vely (n=3). Following the restora�on, five 1 mm2 s�ckshaped specimens were prepared from each tooth with a slow-speed diamond trim blade (Isomet, Buehler, Lake Bluff, Illinois, USA) (n = 15). Specimens were subjected to µTBS stress at a crosshead speed of 0.5 mm/min (Bisco, Schaumburg, IL, USA). Generalized linear model and Tukey's test were used for sta�s�cal analysis (p ≤ 0.05). Caries removal technique was considered significant between all groups (p≤0.001). The mean of µTBS ranged from 14.2 megapascal (MPa) (%95CI: [12.1-20.5]) to 26.4 (%95 CI:[11.7- 28.4]). The mean±standard devia�on of µTBS were obtained as 19.5±3.9 MPa for SSRB, 16.4±3.3 MPa for CRB, 15.0±3.0 MPa for the TCRB&BAG group and 25.1±2.1 MPa for the TCRB&Al2O3 groups, respec�vely. ICDAS scores showed sta�s�cally significant effect for µTBS values (p≤0.001). Similar µTBS values were obtained for ICDAS 0 (20.1±4.9) and ICDAS 3 (19.9±4.6) scores, which are higher than ICDAS 4 (17.9±4.4) and ICDAS 5 (18.2±5.6) scores. In conclusion, the µTBS for sound den�ne were less affected by the caries removal technique. Within the limita�ons of this study, it can be concluded that the air-abrasion with 29 µm Al2O3 may be preferred to increase µTBS for deep carious lesions.