Influence of antimicrobial photodynamic therapy on carious lesion: clinical analysis of the restorations and microbiological analysis of dentin

Abstract

This clinical study is to evaluate the antimicrobial photodynamic therapy (PDT) in caries in deciduous teeth, through clinical evaluation of restorations and microbiological analysis of dentin. The sample will be composed of children (n = 20) of both genders, between 6 and 8 years of age, which have active caries with cavitation reaching dentine, located on the occlusal surface (Class I) of deciduous molars counterparts. The selective removal of caries lesion will be performed, considering that, in the surrounding walls, will be removed all necrotic dentin and affected dentin (demineralized) by means of steel drills at low speed, and the pulp wall will be performed only the removal of necrotic dentin with curettes, maintaining the affected dentin. The deciduous molars counterparts of each child will be randomly assigned into two groups according to the treatment of carious lesions: 1) absent PDT (control) and 2) PDT. To Antimicrobial Photodynamic therapy will be use the laser InGaAIP low intensity, wavelength 660 nm, the red region of the light spectrum, power of 100mW and energy density of 640 J / cm2 (18 J) for 180 seconds, associated with the photosensitizer toluidine blue 0.01%.After treatment of the affected dentin will be performed extensive washing for 1 minute. For microbiology analysis (n=10), collection of the pulp wall dentine will be carried out in three periods: before treatment of carious lesions, after the selective removal of the lesion caries and after treatment of affected dentin. Pulp protection with calcium hydroxide cement and glass ionomer cement will be carried out and subsequently phosphoric acid etching to 35%. The deciduous molars will be restored with adhesive (Single Bond 2 - 3M) and composite resin (Z250 - 3M). For the clinical analysis of the restorations (n = 20), three calibrated and experienced professionals will use the criteria United States Public Health Service (USPHS) modified in periods: 7 days (after polishing) and 6 months after completion of the restorations. During the microbiological analysis, colony forming units (CFUs) will be counted and the results are expressed as CFU / mg of remaining dentin. The data will be analyzed to choose the appropriate statistical method. (AU)