Does Low-Level Laser Therapy Affect Recovery of Lingual and Inferior Alveolar Nerve Injuries?

Iatrogenic damage to the inferior alveolar nerve (IAN) and lingual nerve (LN) may occur during routine oral and maxillofacial surgery procedures. The primary aim of this study was to determine, using a prospective, double-blind, randomized controlled clinical trial, whether the proportion of nerve-injured patients with postoperative neurosensory improvement over a 3-month period differed significantly between a control group and a low-level laser therapy (LLLT) group.

The study sample consisted of 35 patients with iatrogenic nerve injury due to third molar odontectomy, dental implant placement, or local anesthetic injection. The investigators used a randomized, double-blind laser delivery system to administer either placebo or LLLT to patients who met the inclusion criteria. The outcome variable of neurosensory improvement was defined as a minimum 1-unit increase from baseline in visual analog scale rating and was based on standard objective clinical neurosensory testing. Study variables included the affected nerve (IAN or LN) and time from injury to treatment (3 to 12 months or >12 months). Univariate statistical analysis (χ² test) was performed to determine significance between the groups.

Neurosensory improvement was observed in 46.7% of the LLLT patients, who showed at least a 1-unit improvement at 3 months, compared with 38.5% improvement for controls (P = .66), regardless of the specific nerve involved (IAN or LN). In addition, no observed difference was noted between the study groups based on time from injury to treatment.

This study failed to provide sufficient evidence to conclude that a difference in neurosensory improvement exists between the LLLT and placebo groups with IAN or LN injuries. However, this study is unique in the prospective double-blind study design and comprehensive neurosensory testing protocols. There is a continued need for further clinical studies on LLLT in oral and maxillofacial surgery nerve injuries.