Effect of Low-Level Laser Therapy on Neurosensory Recovery After Dental Procedures

A wide variety of dental procedures as local anesthetic injections, endodontic therapy and some oral and maxillofacial surgical procedures including dentoalveolar surgery, tooth extraction, placement of dental implants, orthognathic surgical procedures, removal of benign or malignant tumors, a direct consequence of maxillofacial trauma and its surgical treatment can cause nerve injury. This study reports the effects of low level laser therapy (LLLT) in 50 patients with sensory nerve impairment following dental procedures.

50 patients with the neurosensory deficit of the lingual nerve (LN) and/or the inferior alveolar nerve (IAN), developed as a consequence of dental or oral and maxillofacial surgery procedures enrolled in this study. Paresthesia of the patients was confirmed by subjective and objective neurosensory tests. Subjective neurosensory evaluation included a rating of the patient’s numbness by visual analog scale (VAS) from 0 (normal) to 10 (most severely affected). Neurosensory deficit was determined when subjective numbness VAS score was greater than 0. Objective neurosensory assessments consisted of three tests: light touch test, two-point discrimination and pain threshold. All patients were treated with low level laser therapy (830 nm, 70 mW) three times a week in 10 sessions. Subjective and objective evaluations were done before and after treatment, and the responses were recorded. The results were evaluated with SPSS 21.0 software package. Statistical analysis was performed by use of single sample Kolmogrov-Smirnov test for normality and the Levene test for homogeneity were used and the data examined by two-way repeated measures ANOVA.

This study included 50 patients (15 female, 35 male), aged between 18 and 67, with a mean of 38 years. The causes of the neurosensory deficiencies were removal of impacted third molar (54%) and other dental procedures as dental implant surgery, cyst enucleation, local anesthesia injection, etc. (46%). Subjective and objective evaluation scores after treatment with LLLT were compared with the scores prior to treatment. There was a significant decrease in neurosensory deficit (p=0,000) and the VAS analysis revealed progressive improvement over time (p=0,001).

It might be concluded that LLLT is beneficial in patients with IAN or LN neurosensory deficit. 

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