Effectiveness of SDF in Arresting Root Caries in Different Fluoridated Areas

At the 94th General Session & Exhibition of the International Association for Dental Research, researcher Mr. Edward Lo, University of Hong Kong, SAR, China, presented a study titled “Effectiveness of SDF in Arresting Root Caries in Different Fluoridated Areas”. The IADR General Session was held in conjunction with the third Meeting of the IADR Asia-Pacific Region and the 35th Annual Meeting of the IADR Korean Division.

The objective of this research study was to compare the effectiveness of annual application of silver diamine fluoride (SDF) solution on arresting root caries in community-dwelling elders living in water‑fluoridated and non-fluoridated areas. This study was conducted both in water-fluoridated (Hong Kong) and non-fluoridated (Guangzhou) areas. Healthy community-dwelling elders who had at least five teeth with exposed root surfaces and not indicated for extraction were recruited and randomly allocated into one of two groups: Gp1 (placebo control) – annual application of soda water; Gp2 (test) – annual application of a 38 per cent SDF solution. Individual oral hygiene instruction and fluoridated toothpaste was provided to all subjects. The status of dental root surfaces were clinically examined by calibrated examiners at baseline and every six months.

A total of 533 elders with 138 root surfaces with active caries lesion were recruited at baseline, 260 elders with 84 active root caries lesions in HK and 273 elders with 54 active root caries lesions in GZ, respectively. After 18 months, 75 (54 per cent) of these lesions were reviewed, 51 and 24 in HK and GZ, respectively. The proportions of active lesions that had become arrested were 32 per cent and 75 per cent in Gp1 and Gp2 in HK (X2 test, P<0.05), and 11 per cent and 87 per cent in Gp1 and Gp2 in GZ (X2 test, P<0.05), respectively. The difference in caries arrest rates in the SDF groups in HK and in GZ were not statistically significant (X2 test, P>0.05).

Based on the 18-month result, the researchers concluded that the annual application of 38 per cent SDF solution can arrest root caries in community-dwelling elders. Furthermore, background water fluoride level does not have a statistically significant influence on the effectiveness of SDF. This clinical trial is still ongoing and longer-term results will be reported later.

The research is supported by the IADR/Colgate Community-Based Research Award for Caries Prevention. – International Association for Dental Research (IADR)