Inferior Alveolar Nerve Reconstruction Research Articles

Immediate Inferior Alveolar Nerve Reconstruction With Ablative Mandibular Resection Results in Functional Sensory Recovery

Ablative mandibular resection with sacrifice of the inferior alveolar nerve (IAN) results in loss of sensation and decreased quality of life. The purpose of this study is to evaluate functional sensory recovery (FSR) of immediate IAN allograft reconstruction performed during ablative mandibular resection at 1year following surgery. This is a single-center retrospective cohort study that included consecutive subjects who underwent mandibular resection with IAN discontinuity and used a nerve allograft of ≥40mm. The primary predictor variable is the use of an immediate nerve allograft in mandibular reconstruction. The main outcome variable is FSR at 1year using the Medical Research Council Scale. Covariates include subject age, sex, specific pathology, nerve gap length, and development of neuropathic pain. Statistical analysis of comparison of neurosensory outcomes was measured by bivariate statistics, weighted values, repeated measures, analysis of variance, and McNemar test. The study sample was composed of 164 subjects, of whom 55 (33.5%) underwent nerve allograft reconstruction and 30 (18.3%) did not have nerve reconstruction. Seventy-nine subjects (48.2%) did not meet the inclusion criteria. In the entire nerve allograft group of 55 subjects, FSR was achieved in 80% at 1year; however, in benign disease alone, 31 of 33 (94%) achieved FSR at 1year. In the nonallograft group (all benign disease), only 2 of 30 (7%) achieved FSR at 1year. The significant covariates were age and pathology. Benign pathologic resections were 5.2 times more likely to achieve FSR than malignancies, and all subjects ≤ 18years of age achieved FSR. After adjusting for age, sex, pathology, nerve gap length, nerve allograft was significantly associated with achieving FSR at 1year (adjusted odds ratio=5.52, 95% confidence interval= (1.03, 29.51), P value=.045<.05). Immediate long-span IAN allograft reconstruction is effective in restoration of sensation with an overall 80% of subjects achieving FSR at 1year, while benign disease resulted in 94% FSR at 1year. Immediate IAN reconstruction should be considered with mandibular resection involving the IAN, especially for children and benign disease.

What Do I Do if There is No Distal Nerve Stump for Inferior Alveolar Nerve Reconstruction?

This technical note describes an innovation that addresses a clinical problem in inferior alveolar nerve (IAN) reconstruction. In some cases of mandibular resection, there is a need to resect a significant amount of the IAN along with the pathologic lesion and this may result in a lack of a distal nerve stump for completion of the neural anastomosis. This technical note offers the option to perform the distal neurorrhaphy into the residual soft tissues with the expectation that axonal sprouting will occur and result in lower lip and chin sensory reinnervation. There are no inherent risks or additional costs. The significance of this technique is that it permits IAN reconstruction in cases where the actual nerve stump is not available and improves patient care. There should be no challenges or delays to implementing this innovation for surgeons who reconstruct the IAN during ablative mandibular resection.

Sensory Outcomes for Inferior Alveolar Nerve Reconstruction with Allograft following Free Fibula Mandible Reconstruction.

As patient survival with head and neck cancer has improved, treatment goals have had to evolve to focus on improving quality of life. Traditionally, patients who have undergone mandibulectomy are left with an insensate chin and lower lip secondary to resection of the inferior alveolar nerve (IAN). The purpose of this study was to critically evaluate the authors' initial experience using processed nerve allografts (PNA) for IAN reconstruction following oncologic mandibulectomy and reconstruction with free fibula osteocutaneous flaps and to assess their patients' sensory outcomes. The authors performed a retrospective review of the first 32 patients who underwent immediate IAN reconstruction with PNA at the time of oncologic mandibulectomy and mandible reconstruction with free fibula osteocutaneous flaps at The University of Texas M. D. Anderson Cancer Center over a 1-year period. Semmes-Weinstein filament sensory testing was conducted at multiple surgical follow-up appointments to evaluate the quality of sensory recovery. Thirteen of the 32 patients underwent postoperative Semmes-Weinstein filament testing. All 13 patients demonstrated partial return of sensation. At a mean follow-up of 8.33 months, the average level of sensation was 60.93% that of the unaffected side of the lower lip. Patients were consistently afforded improvement in lower lip sensation using PNA-based IAN grafting as an adjunct to free fibula-based mandible reconstruction. The procedure adds no additional surgical morbidity and has shown consistent positive results.

DANG (Depth-Adjusted Nerve Guide) – A Technical Note

Traditional surgical approaches to the inferior alveolar nerve (IAN) pose a technical challenge and risk iatrogenic damage to healthy, uninvolved nerve tissue. The use of computer-assisted virtual surgical planning and fabrication of surgical guides has shown efficacy in various craniomaxillofacial surgical procedures, and may provide greater precision in accessing the inferior alveolar canal and allow for a more conservative approach. The addition of a depth control feature to a tooth-borne and bone-borne surgical guide, with the use of a standard contra-angle handpiece, provides safe and efficient access for IAN repair. This report describes this novel technique involving a guided transoral approach to the IAN for excision of a neurofibroma of the inferior alveolar nerve, with immediate peripheral nerve allograft IAN reconstruction.

Inferior alveolar nerve reconstruction in extensive mandibular resection: Technical notes

The inferior alveolar nerve (IAN) is a sensitive branch of the mandibular nerve innervating the lower lip, the chin, the buccal mucosa and the teeths. Lesions of the IAN are reported to occur in the 64,4% of maxillo-facial procedures, leading to anesthesia, hypoestesia and/or neurogenic discomfort. An extensive segment of the nerve can be moreover removed during mandibular resection for benign or malignant pathologies. Nervous grafts can be used in these cases to restore the nerve continuity. In order to optimize the procedure and to allow a concomitant mandibular osseous reconstruction, the Authors identified several standardized steps. The technique described allows to perform confortable and safe nervous anastomoses and to reduce the risk of damage and tension during the flap insetting phases.

The Inferior Alveolar Nerve: To Graft or Not to Graft in Ablative Mandibular Resection?

To determine contemporary surgical decision-making processes regarding the use of a nerve graft with ablative mandibular resection and to identify utilization barriers among head and neck surgeons. An online electronic survey that queried practice patterns and subjective opinions regarding inferior alveolar nerve (IAN) grafting at the time of mandibular resection was distributed to head and neck surgeons and oral and maxillofacial surgery residency program directors (N=249) by use of REDCap. The response rate was 37%. Only 10.6% of respondents perform IAN reconstruction "always" (60% "usually" or "sometimes" and 28.8% "rarely" or "never") with ablative benign mandibular resection, whereas only 1.1% perform IAN grafting always (10-20% usually or sometimes and 89% rarely or never) with ablative malignant mandibular resection. Among the 93 participants, the most important utilization barriers were lack of evidence for improving quality of life, potential impact of radiation on nerve healing, and lack of efficacy for restoration of neurosensory function. Despite evidence-based literature showing the efficacy of immediate IAN grafting with ablative benign mandibular resection, most head and neck surgeons do not perform this procedure routinely in patients with benign or malignant mandibular pathology. Future research should focus not only on the achievement of functional sensory recovery but also on the impact of IAN grafting on improved quality-of-life indicators in both benign and malignant mandibular disease, with and without adjunctive chemoradiation therapy.

A patient who underwent inferior alveolar nerve reconstruction with nerve conduit after mandibulectomy

A patient who underwent inferior alveolar nerve reconstruction with nerve conduit after mandibulectomy

Virtual Surgical Planning for Inferior Alveolar Nerve Reconstruction

The purpose of this study was to assess the outcomes after preoperative virtual surgical planning (VSP) for inferior alveolar nerve (IAN) reconstruction in ablative mandibular surgery. We performed a retrospective evaluation of consecutive surgical cases using standard VSP for hard tissue resection and reconstructive surgery in addition to IAN VSP performed simultaneously during surgery. Cases were assessed regarding the planning time, additional costs involved, surgeon's subjective impression of the process, accuracy of the prediction during surgery, and operative time during surgery compared with cases performed without VSP. The study sample was composed of 5 cases of mandibular resection for benign disease, with bony, soft tissue, and neural reconstruction with the use of VSP. The addition of IAN reconstruction to the VSP session added no additional expense to the planning session but resulted in an additional 22.5minutes (±7.5minutes) for the webinar session. From a subjective standpoint, IAN VSP provided the surgeon with a discreet plan for surgery. From an objective standpoint, IAN VSP provided the exactlength and diameter of nerve graft required for surgery, facilitated the surgeon's ability to visualize the actual nerve graft procedure, and limited the additional time required for simultaneous nerve reconstruction. Despite perceived prejudice against simultaneous IAN reconstruction with complex mandibular resection and reconstruction, the use of IAN VSP may facilitate the actual surgical procedure and result in considerably improved patient outcomes without considerable additional time or cost associated with this protocol.

Réhabilitation sensitive du nerf alvéolaire inférieur après mandibulectomie interruptrice

The sacrifice of inferior alveolar nerve (IAN) is usual in case of resection of mandibular tumors and is responsible for disabling sensory disorders, drooling and lip incompetence. We report the case of a reconstruction of the IAN by means of an autologous nerve graft after segmental resection of the mandible. A 27-year-old man presented with a recurrence of mandibular ameloblastoma. Treatment consisted in segmental mandibulectomy with resection of the IAN. Bone reconstruction was performed with a fibula free flap and IAN reconstruction was obtained by mean of a 7-cm nerve graft obtained from the greater auricular nerve (GAN). At the 6th postoperative month, the patient had recovered a normal sensitivity of his lower lip and chin. Latency of somatosensory evoked potentials was similar for both sides. The repair of the IAN by nerve autograft is a simple procedure that allows for good sensitive rehabilitation. The use of the GAN is well suited from its anatomy and from the moderate ear sensory sequelae.

Inferior alveolar nerve reconstruction with interpositional sural nerve graft: A sensible addition to one-stage mandibular reconstruction

Inferior alveolar nerve reconstruction with interpositional sural nerve graft: A sensible addition to one-stage mandibular reconstruction

Inferior alveolar nerve reconstruction with interpositional sural nerve graft: A sensible addition to one-stage mandibular reconstruction

This study was to evaluate the sensory recovery in the lower lip and chin in patients who underwent segmental mandibulectomy involving inferior alveolar nerve and simultaneous reconstruction with fibular osteoseptocutaneous flap and interposition sural nerve graft. From 1993 to 2004, a total of 20 patients underwent segmental mandibulectomy, simultaneous fibula osteoseptocutaneous flap reconstruction and interpositional sural nerve graft. Twelve patients were available for the study. There were seven male and five female patients with average age of 35.8 years (16-52 years). The sense at the lower lip and chin was measured by two-point discrimination both at the operated and non-operated side at an average of 64.3 months (12-146 months). The operated side revealed an average of 13.7mm for static (STPD) and 13.3mm for moving two-point discrimination (MTPD) at the lower lip and 13.7mm for static and 13.4mm for MTPD at the chin. Data from the non-operated side averaged 3.4mm for static and 3.2mm for MTPD at lower lip and 5.1mm for static and 4.5mm for moving discrimination at the chin. All patients recovered better than protective sensation on the operated side, which was sufficient to prevent self-mutilation, preserve comprehensible speech and maintain oral competence. No patient complained of significant donor site morbidity. Simultaneous reconstruction of a segmental mandibulectomy involving inferior alveolar nerve with a fibula osteoseptocutaneous flap and interpositional sural nerve graft offers simultaneous replacement of mandibular architecture and restoration of protective perioral sensation.

Reconstruction of the Inferior Alveolar Nerve with Bioabsorbable Polyglycolic Acid Nerve Conduits

Iatrogenic injury to the inferior alveolar nerve can result in debilitating anesthesia, dysesthesia, and allodynia. The authors report their experience with polyglycolic acid nerve tubes in inferior alveolar nerve reconstruction. Five patients with iatrogenically injured inferior alveolar nerves underwent reconstruction with polyglycolic acid nerve tubes performed by the senior author (A.P.T.). Patient charts were reviewed retrospectively. Resolution of pain, narcotic medication use, neuropathic pain medication use, and patient satisfaction with surgery were assessed by means of patient surveys. Sensation recovery was assessed with the Ten Test. Costs of surgery were calculated and adjusted to 2010 U.S. dollars using the consumer price index. Survey response rate was 100 percent. All patients suffered from preoperative pain and sensation loss. Preoperatively, 80 percent of patients used prescription narcotic and 100 percent of patients used neuropathic pain medications. Average time from injury to reconstruction was 14 months. Operative time averaged 240 minutes, and total surgical costs averaged $8177. At average follow-up of 47.8 months, Ten Test results averaged 3.3. Average time to maximum recovery of sensation and reduction of pain was 8 months and 7 months, respectively. One hundred percent of patients experienced pain relief, with an average 46 percent reduction in pain. Postoperatively, 100 percent of patients discontinued all narcotic and neuropathic pain medications. The use of polyglycolic acid nerve tubes in the reconstruction of iatrogenically injured inferior alveolar nerves achieves diminution of pain and variable sensory recovery. This technique is cost effective and carries no donor-site morbidity. : Therapeutic, IV.

Experiences with microsurgical reconstruction of the inferior alveolar nerve

In select cases, immediate or delayed inferior alveolar nerve reconstruction is indicated. The current state of the art indicates that when nerve reconstruction is to be undertaken, optimal results are achieved via microsurgical instrumentation. Specific technical and biologic considerations that have been found to be relevant in microsurgical reconstruction of the inferior alveolar nerve are discussed.