Pit and fissure sealants are a widely used preventive intervention to reduce occlusal dental caries. Long‑term success of sealants depends largely on their retention, and materials that combine bioactivity with durable bonding are of clinical interest. Giomer‑based sealants incorporate surface pre‑reacted glass ionomer fillers intended to provide bioactive properties, but concerns remain about bonding durability when such materials are applied with mild self‑etch primers. This randomized clinical trial tested whether mechanical surface conditioning using bioactive glass air‑abrasion prior to placement would affect sealant retention and caries prevention over a 12‑month follow‑up.
Design: The investigation was a parallel‑arm randomized clinical trial. Ninety‑six participants were enrolled and each contributed one eligible, sound permanent molar to the study. Participants were randomly allocated in equal numbers (n = 48 per group) to either:
Clinical assessments were performed at baseline, 6 months, and 12 months. The primary outcome measure was sealant retention at 12 months, evaluated using Simonsen's criteria. Secondary caries incidence was recorded as a secondary outcome using modified United States Public Health Service (USPHS) criteria.
Statistical analysis: Intergroup comparisons were performed using the Chi‑square test. Intragroup comparisons across time points used Cochran's Q test followed by multiple comparisons. Relative risk (RR) with 95% confidence intervals was calculated to compare rates of retention failure between groups. Statistical significance was defined as p ≤ 0.05.
Retention at 6 months: Complete sealant retention was observed in 91.7% of teeth in the air‑abraded intervention group and 75.0% in the comparator group. This difference did not reach conventional statistical significance (p = 0.068).
Retention at 12 months (primary outcome): Complete sealant retention at 12 months was substantially higher in the intervention group (87.5%) compared with the comparator group (33.3%). The difference between groups at 12 months was statistically significant (p < 0.0001).
Relative risk: Teeth in the intervention group exhibited a markedly lower risk of sealant retention failure relative to the comparator group. The reported relative risk of retention failure for the intervention arm was 0.1875 (95% CI: 0.0864–0.4069), corresponding to an 81.25% lower risk of failure in the air‑abraded group (p < 0.0001).
Secondary caries incidence: During the 12‑month follow‑up no difference in secondary caries incidence was detected between the two groups (p = 1.0000).
In this randomized trial involving young adults and single permanent molars per participant, pretreatment of fissures with bioactive glass air‑abrasion prior to application of a giomer‑based sealant significantly improved sealant retention at 12 months compared with sealant placement without mechanical conditioning. The intervention reduced the risk of retention failure by more than 80% relative to the comparator in this study population.
No difference in secondary caries incidence was observed within the 12‑month follow‑up window, indicating that enhanced retention achieved with air‑abrasion did not translate into detectable differences in caries outcomes over one year. The authors suggest that incorporating mechanical surface conditioning before sealant placement may enhance the longevity of giomer sealants without compromising short‑term preventive efficacy.
Clinicians considering giomer‑based fissure sealants may weigh the potential retention benefits of air‑abrasion pretreatment against clinical workflow and patient factors; longer follow‑up would be needed to determine whether improved retention leads to sustained reductions in caries incidence beyond 12 months.
The randomized trial is registered on ClinicalTrials.gov (NCT06003452). The study received ethics approval from the Research Ethics Committee of the Faculty of Dentistry, Cairo University (Approval ID: 32424). Written informed consent was obtained from all participants, and the trial was conducted in accordance with the Declaration of Helsinki. The authors declared no competing interests.
This summary is based on the published randomized controlled trial: Khallaf YS et al., BMC Oral Health, 2026;26(1):1662. DOI: 10.1186/s12903-026-09691-8. Detailed reference lists and methods are reported in the full article.