Effect of low-level laser therapy (GaAlAs) on bone regeneration in midpalatal anterior suture after surgically assisted rapid maxillary expansion

Objective. The aim of this study was to evaluate the effects of laser therapy on bone regeneration in the midpalatal anterior suture (MPAS) after surgically assisted rapid maxillary expansion (SARME). Methods. Thirteen patients aged between 18 and 33 years old with maxillary transverse deficiency (>= 7.0 mm) were evaluated. All patients underwent subtotal Le Fort I osteotomy with separation of the pterygomaxillary suture with the use of Hyrax expander, and were divided into 2 groups: control group (n = 6) and laser group (n = 7). A GaAlAs laser (P = 100 mW, lambda = 830 nm, empty set = 0.06 cm(2)) was used. The laser was applied in 8 treatment sessions with intervals of 48 hours. Each treatment session consisted of laser applications, per point (E = 8.4J, ED = 140J/cm(2)), at 3 points on the MPAS, and total dose of E = 25.2 J, ED = 420 J/cm(2). Digital radiographs were taken before the surgical procedure and at 1-, 2-, 3-, 4-, and 7-month follow-up visits. Optical density analysis of the regenerated bone was performed using Adobe Photoshop 8.0 software. Results. Bone regeneration associated with the use of laser after SARME showed a statistically significant difference. A higher mineralization rate was found in the laser group (26.3%, P < .001) than the control group. Conclusion. Low-level laser irradiation (GaAlAs) accelerates bone regeneration in MPAS after SARME. However, the optical density measurements after 7 months of follow-up were lower in comparison with the preoperative measurements. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: e38-e46)