Silver Diamine Fluoride Pilot Study (SDF)

This pilot study will compare 1) Silver diamine fluoride (SDF) and fluoride varnish to 2) Placebo and fluoride varnish (conventional prevention) in the management of early approximal carious lesions. Early approximal carious lesions refers to decay between teeth, diagnosed with radiographs, not extending more than 1/3 of the way into dentin. Management of early approximal carious lesions refers to halting lesion progression, or encouraging lesion reversal after an early carious lesion is detected.

SDF provides a novel, low-cost intervention option for managing early carious lesions that could potentially bridge the 'gap' between non-operative and operative options; thus, postponing the first placement of a restoration. SDF has been used in arresting carious lesions for more than 100 years. However, SDF has never been tested in the arrest of approximal caries lesions in permanent teeth.

SDF acts to both prevent and arrest tooth decay in multiple ways: 1) it acts on the body of carious lesions by precipitating silver ion into the lesion, thus blocking diffusion pathways for cariogenic acids; 2) it interacts with dental enamel leading to the formation of fluoroapatite crystals making the tooth surface more acid resistant; and 3) the precipitated silver from SDF acts as a bactericidal agent disturbing the formation of cariogenic biofilm.

Inclusion criteria

• Presence of at least one approximal caries lesion (scores RA1, RA2, RA3 according to the ICCMS radiographic scoring system) in one of the posterior teeth (premolars and molars) presented with full contact with the adjacent tooth.
• All the surfaces eligible for this study will be included.

Exclusion criteria

• The approximal lesion detected in the radiograph has advanced dentine lesion (RB4, RC5, or RC6)
• or is adjacent to a lesion that is either filled or will receive a filling at the time of enrollment.