Photobiomodulation Efficacy of Major Salivary Glands in Children With Caries Activity: Study Protocol for Randomized, Double-blind, Placebo-controlled, Parallel-group Clinical Trial

Dental caries represents one of the most prevalent diseases among children around the world. Saliva plays a preponderant role in the process of demineralization- remineralization of the dental surface. Patient salivary characteristics, such as flow rate, pH, and buffering capacity, provide relevant information about patient's risk for developing carious lesions. Photobiomodulation has shown promising results to improve salivary flow rate, as well as buffer capacity in the adult population. The purpose of this trial is to evaluate the efficacy of photobiomodulation of the major salivary glands on salivary parameters in children with caries activity.

Methods: This protocol details a randomized, double-blind, parallel-group, controlled trial evaluating salivary parameters through photobiomodulation in children. Seventy-eight 6- to 12-year-old participants will be randomly divided in two groups: 1) the photobiomodulation experimental group (G1) (n=39), 2) the photobiomodulationn placebo group (G2) (n=39). Infrared light will be applied in 16 intra and extraoral points and the placebo, respectively. The unstimulated salivary sample will be taken before and immediately after the application once a week, for three consecutive weeks. Salivary samples will be analyzed for flow rate, pH and buffering capacity. The primary outcomes are difference in salivary flow rates between the G1 and the G2. The secondary outcomes are difference in salivary pH and buffering capacity between the G1 and the G2 group.