Pornpailin KasemkhunSiriruk NakornchaiAraya PhonghanyudhNatchalee SrimaneekarnMahidol University2021-02-032021-02-032020-01-01International Journal of Paediatric Dentistry. (2020)1365263X096074392-s2.0-85099744660https://repository.li.mahidol.ac.th/handle/20.500.14594/60921© 2020 BSPD, IAPD and John Wiley & Sons Ltd Background: Bonding before sealant application enhances retention on saliva-contaminated sound teeth; however, there are few studies of bonding's efficacy on sealant retention on occlusal caries. Aim: To evaluate a bonding agent's efficacy on sealant retention on occlusal caries and caries transition. Design: One hundred twenty pairs of first permanent molars with occlusal caries (ICDAS 2-4) from 98 children aged 7.3-9.9 years were included. One molar was randomly selected to use bonding (Adper™ Single Bond 2, 3M ESPE) applied before sealant application (Helioseal®clear, Ivoclar Vivadent). Bonding was not used on the contralateral tooth. Retention was determined using Simonsen's criteria; caries transition was evaluated using ICDAS scores, DIAGNOdent values, and bitewings at baseline, 6, 12, and 24 months. Data were analyzed with McNemar's and Fisher's exact tests. Results: Bonding agent use significantly increased sealant retention rates (P <.001). Bonded (B) sealants had a higher retention rate (83.3%) than non-bonded (NB) sealants (53.7%). The difference in the caries-transition rate was not significant between the groups (P >.05). Three teeth (1.4%; NB:B = 2:1) were restored due to radiographic dentin-caries progression. Conclusions: Using a bonding agent before applying sealant on permanent molar occlusal caries (ICDAS 2-4) significantly enhanced sealant retention. Caries progression was rarely detected at the 24-month follow-up.Mahidol UniversityDentistryArticleSCOPUS10.1111/ipd.12758