Comparative efficacy of Depotphoresis and diode laser for reduction of microbial load and postoperative pain, and healing of periapical lesions: a randomized clinical trial

Aim: To compare the efficacy of depotphoresis and diode laser (DL) for reduction of microbial load and postoperative pain, and healing of periapical lesions in teeth with necrotic pulp. Methods: Ninety patients (98 roots) with pulp necrosis and chronic periapical lesions were randomized into three groups (n=30) of depotphoresis, diode laser, and control. Bacterial samples were collected from all roots at each treatment phase (S1: immediately after access cavity preparation, S2: immediately after cleaning and shaping, S3: one week after intracanal medicament). Analysis of bacterial reduction was performed using “Colony Forming Unit Counting” method. Level of pain was measured before and at 6, 12, 24, 48 and 72 hours after treatment using a visual analog scale (VAS). Cone-beam computed tomography (CBCT) images were obtained before and 6 months after treatment to assess the healing of periapical lesions based on their apicocoronal, mesiodistal and buccolingual diameter. Kruskal-Wallis and The Mann-Whitney test was used to determine the colony forming units and Compare the level of pain at different times between the groups of study, whilst the Univariate analyses using the chi-square or Fisher exact test were used to show the correlation of the outcomes with variables to identify the potential predisposing factors (P<0.05). Results: At S1, no significant difference was noted among the three groups in microbial load. At S2 and S3, there was a statistically significant lower bacterial count in DL (P=0.041) and depotphoresis group (P=0.001) respectively, compared to other groups. All patients had mild pain at all time points post-treatment. Also the size of the preoperative periapical lesions had no significant effect on the outcome of endodontic treatment (p>0.05). Conclusions: Root canal disinfection by depotphoresis and diode laser significantly decreased the microbial load as well as the post-endodontic pain and resulted in complete healing of some lesions in a short time.