Investigation of the efficacy of two different laser types in the treatment of lower lip paresthesia after sagittal split ramus osteotomy.

Orthognathic surgery involves invasive and major surgical procedures commonly used to correct maxillofacial deformities. Bilateral sagittal split ramus osteotomy (BSSO) is often used to treat dentofacial anomalies related to the mandible, but it can result in various complications, the most common of which is inferior alveolar nerve damage. Nerve damage-induced paresthesia of the lower lip significantly affects patient comfort. Medical treatments such as steroids and vitamin B, low-level laser therapy (LLLT), and platelet-rich fibrin (PRF) can be used as supportive therapies for nerve regeneration after damage. This study aimed to investigate the effectiveness of two different types of lasers in treating lower lip paresthesia after BSSO. This clinical trial was a controlled, single-center, prospective, single-blind, randomized study. Thirty patients were included in the study and randomly assigned to three groups: Group I (laser GRR, n = 10) received transcutaneous and transmucosal GRR laser treatment, Group II (Epic10 laser, n = 10) received transmucosal and transcutaneous Epic10 laser treatment, and Group III (vitamin B, n = 10) received B-complex vitamin tablets orally once a day. Two-point and brush tests were performed six times at specific intervals, and a visual analog scale was used to evaluate pain and sensitivity. Both vitamin B and laser therapies accelerated nerve regeneration. The contribution of the laser groups to the healing rate was better than that of the vitamin B group. Although there was no statistically significant difference between the two laser groups, clinical observations indicated better results in the GRR laser group.

Surgical management of damaged inferior alveolar nerve caused by endodontic overfilling of calcium hydroxide paste.

AIM: To evaluate the neurosensory outcome of management of damaged inferior alveolar nerves caused by endodontic overfilling and to assess the efficacy of delayed surgical intervention. METHODOLOGY: Nine patients who underwent surgical removal of extruded endodontic material were included. All patients were evaluated for neurosensory function using a set of standardized tests. The outcome of surgical intervention was evaluated through patient interview and quantitative statistical analysis. RESULTS: Surgical procedures included foreign body removal, microsurgical external/internal decompression, excision of neuroma followed by nerve repair, and excision of damaged nerve segment with interpositional nerve graft. Seven of the nine patients had significant improvement according to the follow-up neurosensory assessment. Four patients reported significant improvement, three patients reported mild improvement and two patients reported no appreciable improvement in the Visual Analog Scale (VAS). Two patients who reported no appreciable improvement in VAS also did not achieve FSR. In these patients, calcium hydroxide was spread widely along the IAN and a surgical approach was obtained via sagittal spit osteotomy. The mean time to reach FSR was 222.7 (±41.8) days with a range of 106-397 days. In the early repair group who received surgery within 60 days, three out of five patients achieved FSR in a mean time of 198.0 (±76.2) days. The mean time to FSR in all four subjects who received surgical attention over 60 days after injury was 241.3 (±139.8) days with a range of 106-397 days. As all four cases in the late repair group with limited amount of nerve injury achieved FSR, only 3 of 5 early repair cases with wide-spread injury achieved a similar outcome. CONCLUSION: The results of this case series confirmed the notion that surgical management of the inferior alveolar nerve is effective in the treatment of nerve injuries caused by endodontic extrusion of calcium hydroxide paste. Delayed surgical repair of the inferior alveolar nerve can be indicated and helpful for the neurosensory recovery of damaged IAN, however, the surgical management was less effective in case of widespread nerve injuries.

Feasibility of a cross-face reconstruction of the mental nerve-A cadaveric simulation study with histomorphometric analysis.

INTRODUCTION: The inevitable sacrifice of the inferior alveolar nerve during oncologic resections results in substantial sensory impairment, impacting crucial functions such as speech, saliva retention, and mastication. This study investigated the feasibility of sensory restoration through cross-face reconstruction of the mental nerve via a contralateral mental nerve branch. METHODS: The cross-face reconstruction procedure was simulated in five formalin-fixed cadavers in both sides to evaluate the anatomic fundamentals and the nerve gap between the mental nerve main trunk and transferred contralateral mental nerve branch. Furthermore, a histomorphometric analysis was performed to assess the cross-sectional area and axon counts. RESULTS: The mean gap distance between the main mental nerve trunk and transferred contralateral branch was 15.3 mm. End-to-end coaptation was achieved in nine out of ten simulations. The mean cross-sectional area was 0.996 mm2 at the main mental nerve trunk and 0.253 mm2 at the coaptation site of the nerve branch. The mean donor-to-recipient axon ratio was found to be 0.3:1. CONCLUSION: The cadaveric simulation demonstrates the feasibility of a cross-face reconstruction of the mental nerve with only minimal gapping. Advantages of the proposed technique include the use of shorter nerve grafts, to minimize donor site morbidity and enable fast reinnervation. This technique may offer a promising method to enhance the quality of life in patients by increasing survival rates and life expectancy.

Efficacy of low-level laser therapy and microsurgery on neurosensory recovery following inferior alveolar and lingual nerve injuries: A systematic review.

Purpose: This systematic review evaluates the relative effectiveness of low-level laser therapy (LLLT) and microsurgery for neurosensory recovery following sustained iatrogenic injuries to the inferior alveolar nerve (IAN) and lingual nerve (LN) more than 6 months in Oral and Maxillofacial surgery procedures. Methods: Six articles were included. The mean age of microsurgery studies was 41.5 years and that of LLLT studies was 31.5 with female predominance in all studies. The majority of the included studies have been based on both subjective and objective assessments for neurosensory, two investigating microsurgery and four investigating LLLT following a Six-month post-IAN and LN injury. Results: Each modality demonstrated positive outcomes in both subjective and objective assessments of neurosensory function. Notably, LLLT exhibited efficacy even when employed beyond a six-month interval following the initial injury. Early intervention is generally recommended, particularly for microsurgical approaches. Conclusion: LLLT shows exciting promise as a minimally invasive approach for neurosensory rehabilitation even after six months of injury, while microsurgery studies revealed an improvement and the recommendation for early intervention post-nerve injury, the potential of LLLT and optimize its use for neurosensory rehabilitation, additional randomized controlled trials with larger sample sizes, longer follow-up periods, and blinding protocols are necessary.

Knowledge and Attitude Among the Saudi Dentists Towards Coronectomy of Impacted Mandibular Third Molars.

Purpose: Compared to the complete extraction of impacted third molars that are in close proximity to the mandibular canal, the coronectomy procedure is used as an alternative, owing to its minimal risk of damaging the Inferior alveolar nerve. Despite clear coronectomy concepts mentioned in the literature, the procedure is debatable. This study aimed to assess the knowledge and attitude towards the coronectomy procedure among dentists in Saudi Arabia. Patients and Methods: The 16 close-ended questionnaire was distributed electronically to 377 dentists over the country. It included the demographic data and the options given to their patients with complicated impacted third molars, and the number of coronectomy they have performed. The retrieved data were exported and transferred to the SPSS software program for analysis. The Chi-squared and Fisher's exact tests were used as appropriate for comparisons. A P-value <0.05 was considered significant. Results: Only 54 (15%) participants performed coronectomy procedure, and only 28.3% of the participants advised their patients to do coronectomy. Nearly two-thirds of the participants (71.9%) were aware of coronectomy procedures, with no significant differences (P> 0.05) between the groups. About 68.9% of the participants agreed that coronectomy aims to protect inferior alveolar nerve damage. More than 60% of participants believed that coronectomy is a reliable technique, while 40.6% of participants claimed that they were capable of deciding whether to do coronectomy or extraction. No significant differences were found between the groups concerning most of the study variables (P> 0.05). Conclusion: Knowledge of Saudi dentists towards coronectomy is good, while their attitude is still low. More learning strategies about coronectomy should be implemented.

A clinical study of inferior alveolar nerve damage caused by Carnoy's solution used as a complementary therapeutic agent in a cystic lesion.

BACKGROUND: Cyst enucleation, which extracts only the tumor with the application of Carnoy's solution (CS), has been suggested as a conservative treatment with a low recurrence rate and morbidity. However, there has been a concern that CS's contact with inferior alveolar nerve (IAN) can cause neurons to degenerate and cause sensory dysfunction. The purpose of this retrospective cohort study aimed to investigate the neurosensory function after surgical treatment with or without the application of CS. METHODS: While controlling the effects of sex, age, follow-up period, and invasion size of the tumor, we performed the binary logistic regression analysis to examine whether or not the sensory function of the patients who were treated with CS (n = 19) for the cyst enucleation procedure was significantly different from those who were not treated with CS (n = 58) at the end of the follow-up period. RESULTS: The logistic regression result showed that the use of CS was not significantly related to the normalness of sensory function at the end of the follow-up period. Rather, the invasion size of the cyst was significantly associated with sensory dysfunction. CONCLUSIONS: CS may be used for patients who are diagnosed with OKC and UAM without much fear of its impact on sensory dysfunction. However, a small number of patients who were treated with CS experienced severe sensory damage and did not recover at the end of the follow-up period, suggesting the need for further analysis of these patients.

Anaesthesia of the inferior alveolar and lingual nerves following subcondylar fractures of the mandible.

A retrospective chart review of 387 patients with condylar and subcondylar fractures revealed 2 cases of inferior alveolar nerve (IAN) and lingual nerve (LN) anaesthesia following the subcondylar fracture. Only 5 cases have been reported previously. The mechanism of action remains unknown but a review of the literature and an analysis of 120 dry human skulls supported the hypothesis that compression of the mandibular nerve at a high level, close to the foramen ovale, could cause anaesthesia. This complication is rare, because it requires compression at a particular angle. The antero-median angulation of the condyle must be close to the foramen ovale, and the fracture must be a unilaterally displaced fracture. The presence of an enlarged lateral pterygoid plate appeared to enhance the risk of compression. The IAN and LN anaesthesia could be resolved after open reduction of the fracture and IAN and LN anaesthesia constitute a strict indication for an early open fracture reduction.

Assessment of inferior alveolar nerve damage using digital infrared thermographic imaging

Oral and Maxillofacial surgery can lead to complications that result in abnormal sensation or movement. Inferior alveolar nerve(IAN) injury can result in dysesthesia, paresthsia of the lower lip and chin, so patients presenting with IAN damage suffer from sensory loss. But diagnosis of the nerve injury is largely limited to the subjective statements made by the patient. Distribution of sympathetic nerves parallels the distribution of the somatosensory nerves. Loss of sensory tone causes a concomitant loss of sympathetic activity, resulting in vasodilation of the cutaneous blood vessels that demonstrates greater heat loss. Digital infrared thermographic imaging(DITI) detects infra-red radiation given off by body. DITI can detect minute difference in temperature from different parts of the body and translates the amount of heat into quantitative data. The area of different temperature correlated with pain or disease can be visualized by corresponding color. The objective of this study was to determine the efficacy of DITI in objectively assessing IAN injury. The 19 normal subjects and the 14 patients underwent DITI scan. The normal subjects received unilateral IAN block anesthesia with 2 ml of 2% lidocaine (IAN bolck group) to evaluate temporary alteration in nerve function. Patient group were patients with unilateral IAN damage (dysesthesia or paresthesia) after surgical treatment(Mn. 3rd molar Extraction, etc.). The surgical procedure performed within 6 months of test. The results were as follows. 1. No significant differences in temperature were found between left and right sides of the lower lip and chin in the control group. 2. Significant temperature differences were found between the anesthetized and non-anesthetized sides of the lower lip and chin in the IAN block group. 3. Significant temperature differences were found between the involved and uninvolved sides of the lower lip and chin areas of the experimental group. The results of the study show that DITI can be an useful and effective means of objectively assessing and visualizing IAN damage.