Effectiveness of silver diamine fluoride in preventing radiation-induced caries - A pilot study

Amal A.K. Noureldin, DDS, MS, PhD Lloyd Mancl, PhD d a ; Amerian Sones, DDS b ; Luz Mendoza, DDS, MBA ; Peter Milgrom, DDS d a Department of Public Health Sciences, College of Dentistry, Texas A&M University, Dallas, TX; Comprehensive Dentistry, College of Dentistry, Texas A&M University, Dallas, TX; North Texas, Dallas, TX; ABSTRACT d Department of Oral Health Sciences, University of Washington, Seattle, WA. c ; b Department of c Dental Department, Prism Health

Background.

Radiation-induced caries (RIC) is a major complication of head and neck cancer radiotherapy. This study evaluated the effectiveness of professionally applied 38% silver diamine fluoride (SDF) in preventing coronal and root RIC.

Methods.

In this randomized, single-blind, placebo-controlled trial, 56 patients were assigned to receive topical 38% SDF or placebo before radiotherapy and at 1 and 3 months after radiotherapy. The primary outcome was caries increment, measured as the number of new decayed, missing (due to caries), or filled tooth surfaces at 1, 3, and 6 months. Secondary outcomes were stimulated salivary flow rate, buffering capacity, gingival index, and oral health–related quality of life.

Results.

Thirty-six participants completed at least 1 follow-up visit (18 SDF, 18 placebo). Mean (SD) participant age was 61 (13) years, and most were men (78.0%). Median caries increment was significantly lower in the SDF group at 3 months (1.0 vs 2.0; P = .027) and 6 months (2.0 vs 3.0; P = .030). At 3 months, 47.1% of SDF participants developed no new lesions compared with 5.9% of those in the placebo group (P = .017). Stimulated salivary flow decreased significantly in both groups, with no between-group differences. No significant differences were observed in gingival inflammation or quality of life measures. 

Conclusions.

Topical 38% SDF reduced RIC progression despite profound hyposalivation, supporting its use as a practical chairside preventive intervention for patients undergoing head and neck radiotherapy. Practical Implications. Because SDF is fast, professionally applied, and does not rely on patient compliance, it may be a valuable addition to oral care protocols before and after radiotherapy.

Download full study HERE or by clicking on the image below.

This clinical trial was registered at ClinicalTrials.gov. The registration number is NCT05403125. 

Copyright ª 2026 American Dental Association. This is an open access article under the CC BY license (http:// creativecommons.org/ licenses/by/4.0/).

Key Words. Caries; radiotherapy; head and neck cancer; silver diamine fluoride. 

JADA 2026: ■ ( ■ https://doi.org/10.1016/j.adaj.2026.05.008