Impact of different restorative treatments for deep caries lesion in primary teeth (CEPECO 1) - study protocol for a noninferiority randomized clinical trial

Background: Due to the lack of evidence to determine the best treatment for deep cavitated caries lesions in primary molars, the search for an effective restorative technique, which results in a minimal discomfort to patients, and reduce the time needed for the treatment, becomes relevant. The objective of this randomized clinical trial was to evaluate if high-viscosity glass ionomer cement (HVGIC) restorations is noninferior to restoration with calcium hydroxide cement associated with HVGIC for treatment of deep lesions in primary molars, as well as the impact of the treatments on cost and discomfort of the patient. Methods: A non-inferiority randomized clinical trial with two parallels arms (1:1) will be conducted. Children with 4 to 8 years will be selected at Clinic of Pediatric Dentistry at Ibirapuera University. 108 teeth will be randomized into two groups: (1) Calcium hydroxide cement associated with HVGIC and (2) HVGIC restoration. Primary outcome will be considered the pulp vitality and to be evaluated after 6, 12, 18 and 24 months by two calibrated examiners. Survival of restorations will also be evaluated in the equal intervals. The duration of dentals treatment and the cost of all materials used will be considered for estimating of cost-efficacy of each treatment. Individual discomfort will be measured after each dental procedure using the Wong-Baker's Facial Scale. For the primary outcome, Kaplan-Meier survival and the long-rank test will be used to comparison between the groups. Cox regression will be performed to assess the influence of variables on the outcome. For all analyzes, the significance level is set at 5%. Discussion: Based on the philosophy of ART, our hypothesis is that the HVGIC restoration is a possible approach to restore the deep caries lesion with pulp vitality without the use of rubber dam and anesthesia.