Inferior Alveolar Nerve Transposition Research Articles

Inferior alveolar nerve repositioning surgical techniques and outcomes – a systematic review

Inferior alveolar nerve (IAN) lateralization (IANL) or transposition (IANT) are both techniques allowing for dental implant placement in posterior atrophic mandibles. The aim of this study was to systematically review the implant survival rate and the complications associated with IAN reposition techniques with simultaneous implant placement in atrophic posterior mandibles.This systematic review was conducted following PRISMA guidelines (Preferred Reporting Items for Systematic review and Meta-Analysis). The review was designed to answer the following PICO question: Is IAN repositioning (I) a safe and efficient technique (O) to treat patient looking for fixed dental rehabilitation of an atrophic posterior mandible (P).Thirty-three articles were reviewed, including a total of 899 patients, and approximately 950 IAN repositioning procedures. Dental implant survival rate ranged between 86.95% and 100% with a mean dental survival rate of 90.16%. Among the 269 patients who underwent IANT, there were 93% immediate neurosensory disturbance, and 15% persistent neurosensory disturbance. Among the 350 patients who underwent IANL, there were 93% immediate neurosensory disturbance, and 6% persistent neurosensory disturbance.IANT and IANL are reliable techniques allowing safe dental implant placement in atrophic posterior mandible with high patient satisfaction. IANL seems to cause less persistent neurosensory disturbances compared to IANT. The level of evidence is poor due to the high number of bias present in the included studies. IAN neurosensory disturbance assessment should be better homogenized in order to increase comparability.

Management and prevention of rare complication of mandibular fracture after inferior alveolar nerve transposition in edentulous atrophied mandible in implant dentistry: An unusual case report

Edentulism can be a debilitating handicap. Nowadays, most dental surgeons believe that the most basic restoration for the edentulous mandible should be an implant retained overdenture with two implants placed in the anterior mandible. Treatment options for edentulous mandible range from complete denture to implant supported fixed restorations implant retained and tissue supported overdentures, implant retained and implant supported over dentures and hybrid fixed prostheses or bone anchored bridges. With proper selection and treatment planning, using dental implants to support restoration replacing missing teeth can provide long lasting functional and aesthetic restorations. However, in atrophic mandible many problems can arise. In this rare case report, we are highlighting some of the challenges involved in management of atrophic edentulous mandible in a diabetic old patient with implant retained tissue supported overdentures, (IRTOD) which later required inferior alveolar nerve (IAN) trans positioning due to severely atrophic mandible and resulted in accidental mandibular fracture. The key to prevent these types of failures is proper treatment planning. With this article we want to enlighten some useful keys for preventing these kinds of failures.

Surgical bone augmentation procedures for oral rehabilitation of patients with oligodontia: A review with a systematic approach

Oligodontia is a developmental dental anomaly defined by the absence of 6 or more permanent teeth, excluding the third molars. We performed a review with a systematic approach and proposed a guideline for the choice of the bone augmentation surgery. The different bone augmentation technique terms were searched in the PubMed and Science Direct database. Clinical studies were eligible if they reported on pre-implant surgery in patients with oligodontia. The database search yielded 400 studies after duplicates removed. Thirty studies were finally included, involving 410 patients. Sixty-three sinus lifts were performed in 37 patients with no failure. Thirteen out of 33 patients with iliac bone transplantation and two out of 24 with parietal bone transplantation had resorption, one out of 4 patients who received allogeneic bone block had complete failure. Seventy-eight patients underwent guided bone regeneration, none had bone loss. No failure was found with the alveolar distraction osteogenesis technique. Four out of thirteen patients developed permanent hypoesthesia after inferior alveolar nerve transposition. The cumulative implant survival rate was 94.4% after bone augmentation procedures. Extensive edentulous areas should be grafted with parietal bone, as iliac grafts present a greater risk of resorption. Smaller edentulous areas should be treated by endobuccal harvesting or guided bone regeneration. Osteogenesis distraction and nerve transposition are effective surgeries for medium-to-large mandibular edentulous spaces. The implant survival rate is not significantly different between implants placed in grafted and nongrafted bone, the appropriate choice of bone augmentation technique can reduce the risk of peri‑implant bone resorption.

Expanding the Surgeon's Armamentarium: Use of the Tubing Technique to Preserve the Inferior Alveolar Nerve During Transposition Procedure.

Severe edentulous posterior mandible atrophy with inadequate bone height superior to the inferior alveolar canal may increase the risk of neurosensory impairment and other complications during inferior alveolar nerve (IAN) transposition (IANT) prior to dental implant insertion. The current report describes the tubing technique as a practical and feasible procedure that ensures IAN preservation during IANT. The technique involves wrapping a standard suction catheter around the exposed nerve to facilitate full coverage. This work presents a retrospective review of 31 patients undergoing IANT procedures followed by immediate placement of dental implants between January 2015 and January 2020. IANT was performed either unilaterally or bilaterally on all patients, followed by IAN tubing before implant placement. A total of 46 IANT procedures involving the tubing technique were performed. Overall, 149 dental implants were inserted during IANT surgeries, with a success rate of 98.6%. Sensory disturbance was documented in 47.8% of the treated sites (left/right mandible) at 1 month (22/46 sites), 21.7% at 3 months (10/46 sites), 6.5% at 6 months (3/46 sites), and 2.2% at 12 months (1/46 sites) postimplantation. In total, except for 1 case, sensory disturbance was fully resolved by the end of the 12-month follow-up period. Taken together, the tubing technique described herein is a practical and reproducible method for protecting the IAN during transposition.

Severe Atrophy of the Posterior Mandible and Inferior Alveolar Nerve Transposition.

The paper presents the inferior alveolar nerve transposition as a successful surgical technique when other treatment options are not possible in the severely resorbed posterior mandible. Based on three clinical cases, this technique is presented in conjunction with implant placement and immediate loading. The paper aims to present the mandibular nerve transposition as a therapeutic method and an important approach, engaging clinicians to use it when other opportunities are impossible.

Dental implant placement with inferior alveolar nerve repositioning in severely resorbed mandibles: a retrospective multicenter study of implant success and survival rates, and lower lip sensory disturbances

BackgroundThe purpose of this study was to analyze medium-to-long-term implant success and survival rates, and lower lip sensory disturbance after placement of dental implants with simultaneous inferior alveolar nerve (IAN) repositioning.MethodsFifteen patients (3 men, 12 women) treated in two centers were included in this retrospective study. The ages of the participants ranged from 19 to 68. A total of 48 dental implants were placed in 23 posterior mandibular segments simultaneously with IAN transposition or lateralization. The residual bone above the IAN ranged from 0.5 to 7.0 mm. Crestal bone changes were measured using cone beam computed tomography (CBCT) images. Disturbance of the IAN was evaluated subjectively using a modified questionnaire.ResultsThe healing process was uneventful in fourteen patients. In one patient, spontaneous fracture of the operated mandible occurred on tenth day after the surgery. The implant in the fracture line was removed at the time of open reduction and fixation. One more implant was lost after 5 years of loading. Therefore, the overall dental implant survival rate was 95.8%, whereas all implants in function were judged as successful after a follow-up period of 1 to 10 years. Transient neurosensory disturbances (ND) were observed in all patients who underwent IAN lateralization and IAN transposition. At follow-up times of 3 years, 5 years, and 10 years, weak hypoesthesia remained in two subjects treated with IAN transposition. None of the patients developed neuropathic pain after the procedure.ConclusionsWithin the limitations of this study, we conclude that reconstruction of severely resorbed mandibles with dental implants in conjunction with IAN repositioning is an effective and reliable technique. Although neurosensory disturbances are the most common complication after surgery, they tend to resolve over time. Advanced surgical skills are required to perform this technique.

Complications Associated with Rehabilitation of a Unilateral Partially Edentulous Mandible with Inferior Alveolar Nerve Transposition and Implant Placement: A Clinical Report.

Rehabilitation of an edentulous posterior mandible to restore function and arch stability can be accomplished with a removable partial denture or an implant supported fixed partial denture. If the alveolus is severely resorbed, implant placement becomes challenging due to inadequate bone and the position of the inferior alveolar nerve. This report details a situation where a mandibular fracture occurred soon after inferior alveolar nerve (IAN) transposition and simultaneous implant placement. The prosthodontic reconstruction was completed using a fixed-dental prosthesis.

Complications associated with inferior alveolar nerve reposition technique for simultaneous implant-based rehabilitation of atrophic mandibles. A systematic literature review

IntroductionSurgical inferior alveolar nerve (IAN) reposition techniques offer an alternative approach to implant-based rehabilitation in patients with severe mandibular atrophy The aim of this systematic review, was to determine the complications associated with the technique and to determine which of two variants (lateralization or transposition) is less invasive. Materials and methodsAn electronic search was conducted in databases complimented by a manual search to identify clinical studies investigating complications derived from these surgical techniques. Only studies of adult humans, published in English during the last seven years were included. The initial search located 78 articles, of which seven were included in analysis on the basis of the following characteristics: four investigated inferior alveolar nerve lateralization (IANL), one inferior alveolar nerve transposition (IANT), and two investigated both reposition techniques. ResultsThis review included data from 289 patients who were recruited for lateralization (N=319) or transposition surgery (N=33) making a total of 352 reposition procedures. Five patients (1.73%) suffered persistent damage to the IAN at the end of the follow-up periods. The overall implant survival rate was 99.26% of a total of 817 implants. The most common complications were neurosensory problems, mandibular fracture, infection, implant loss, and insufficient anatomical reconstruction of the atrophic mandible; neurosensory complications (hypoesthesia, paraesthesia, and hyperesthesia caused by traumatic damage to the nerve) were the most prevalent. ConclusionsLateralization of the inferior alveolar nerve would appear to be less invasive as it produces lower percentages of persistent neurosensory disorders (1.56%) than transposition (12.12%). Nevertheless, both techniques offer a viable approach to implant placement in edentulous atrophic mandibles, obtaining predictable clinical and radiological results after 5 years implant loading.

Incidence of neurosensory disturbance and success rates of solid-screw implants placed in conjunction with inferior alveolar nerve transposition

Background:Implant-supported prosthetic rehabilitation of a severely atrophic posterior mandibular alveolar ridge is a real challenge. Implant placement in such situations is very difficult and implies the risk of inferior alveolar nerve (IAN) damage.Purpose:The purpose of this study is to evaluate the incidence of neurosensory disturbance and the cumulative survival of dental implants placed after the IAN transposition (IANT) procedures followed by dental implants placement.Materials and Methods:Twenty International Team for Implantology implants were placed in eight patients following unilateral IANT. In two patients, nerve transposition was performed bilaterally, and hence, a total of 10 IAN transposition surgeries were performed. Neurosensory dysfunction was objectively evaluated by using light touch test (LT), pain test (PT), and 2-point discrimination test (2-DT). In addition, patients were asked to answer a short questionnaire to investigate the individual feeling of discomfort and advantages related to this surgical technique. The mean follow-up periods were 47.1 months (range 12–78 months).Results:Neurosensory disturbance (i.e., disturbance registered by the LT, PT, and 2-DT tests) was experienced in 2 of 10 cases. The cumulative implant survival was 100%. However, at the time of data analysis (12–79 months after surgery), all patients indicated that they would go through the surgery again.Conclusion:IANT can permit the placement of implants with adequate length and good initial stabilization as used in routine sites, with the same favorable prognosis. All patients felt that they had received benefits from their new prostheses in terms of improved comfort, chewing efficiency, and esthetics.

Alternativas para reabilitação com implantes dentários em mandíbula posterior atrófica

An adequate bone volume is mandatory for a favorable long-term prognosis in patients treated with dental implants. The vertical deficiency of posterior mandible is a common condition in partially edentulous patients, in which vertical bone augmentation procedures or inferior alveolar nerve transposition become necessary for the dental implant rehabilitation. Thus, the aim of this study was to discuss options of vertical bone augmentation techniques in atrophic posterior mandibles and to present, as case reports, alternatives for the rehabilitation of patients with this condition. So, three alternatives of treatment were presented: the use of Cytoplast titanium-reinforced membrane over autogenous and xenogenous particulate bone graft; sandwich osteotomy; and nerve transposition. In the three reported cases, the chosen surgical techniques showed to be appropriated and allowed the placement of longer implants. No significant complications were observed and all the patients were satisfied with the performed treatment. It is possible to conclude that the reconstruction of atrophic posterior mandible remains a challenge to the professionals, who must know the various existing techniques and choose the most suitable one to each patient.

Pedicled segmental rotation techniques for posterior mandible augmentation: a preliminary study

Rehabilitation of the atrophic posterior mandible is a challenge in dental practice. Conventional treatments include the segmental sandwich osteotomy or inlay bone grafting (IBG), onlay bone grafting (OBG), short implants, distraction osteogenesis, and inferior alveolar nerve transposition (IANT), each with its downsides. This case series is reported to introduce a modification of IBG – pedicled segmental rotation (PSR) for the reconstruction of co-existing vertical and horizontal defects in the posterior mandible. Ten healthy patients with vertical–horizontal defects (no vertical bone walls and basal bone width <5 mm) were included. Posterior mandibular defects were treated with PSR, PSR + IANT, or PSR + OBG. In PSR, a pedicle-preserved segment is up-fractured superiorly and then flipped 90° to a vertical position. The segment is then supported with inorganic bovine bone and autogenous bone particulates. Cone beam computed tomography was performed preoperatively and at the 4-month follow-up, in addition to clinical examinations. Soft tissue healing was uneventful. Radiomorphometric analysis showed a mean new bone volume of 647.79 ± 81.31 mm3 (ΔH = 7.13 mm), 836.99 ± 119.14 mm3 (ΔH = 7.8 mm), and 640.20 ± 50.13 mm3 (ΔH = 6.59) in the PSR, PSR + OBG, and PSR + IANT groups, respectively. The proposed PSR technique used in this case series showed promising results for vertical and horizontal augmentation of the atrophic posterior mandible before placement of dental implants.

Transposition of inferior alveolar nerve with simultaneous insertion of implants with cone‐Morse: six years follow up

Transposition of inferior alveolar nerve with simultaneous insertion of implants with cone‐Morse: six years follow up

Assessment of the anterior loop of the inferior alveolar nerve via cone-beam computed tomography.

ObjectivesThe aim of this study was to evaluate different anatomical variants of the anterior loop of the inferior alveolar nerve (IAN) via cone-beam computed tomography (CBCT).Materials and MethodsCBCT images of 71 patients (36 males and 35 females) were evaluated. We used the classification described by Solar for IAN evaluation. In this classification, three different types of IAN loops were introduced prior to emerging from the mental foramen. We classified patients according to this system and introduced a new, fourth type.ResultsType I was seen in 15 sites (10.6%), type II in 39 sites (27.5%), and type III in 50 sites (35.2%). We found a new type in 38 sites (26.8%) that constituted a fourth type.ConclusionWe found that type III was the most common variant. In the fourth type, the IAN was not detectable because the main nerve was adjacent to the cortical plate and the incisive branch was thinner than the main branch and alongside it. In this type, more care is needed for surgeries including inferior alveolar and mental nerve transposition.

Relieving neuropathic pain of the mental nerve by vertical bone augmentation between the mental foramina: A novel technique in place of conventional inferior alveolar nerve transposition

ObjectiveNeuropathic pain of the mental nerve is associated with extensive bone resorption in the atrophic edentulous mandible. One of the treatment options is inferior alveolar nerve transposition, which repositions the nerve canal deeper in the alveolar bone, but it carries a high risk of nerve damage, especially in cases of severe alveolar resorption. Here, we report a novel technique for relief of neuropathic pain of the mental nerve in an elderly edentulous patient with severe alveolar resorption who became unable to wear a complete denture. MethodsThis procedure was performed under general anesthesia. Bone was harvested from both coronoid processes, and bone augmentation was performed between the mental foramina via the extraoral approach to preserve the surrounding periosteum on the lowered mandibular bodies and around the mental nerves. The grafted bone was trimmed and fixed with bioresorbable plates and screws after decortications of the residual cortical bone. ResultsThe procedure provided sufficient height between the foramina and the alveolar crests. Complete relief of neuropathic pain was achieved postoperatively and following adjustment of the patient's complete denture during oral rehabilitation. ConclusionsThis novel method enabled repositioning of the alveolar nerve canal and may be a feasible alternative to IAN transposition in patients with severe alveolar resorption.

Subjective and qualitative assessment of neural disturbance after inferior alveolar nerve transposition for dental implant placement.

BackgroundThe purpose of this retrospective study was to accumulate data regarding the quality of postoperative neurosensory function after inferior alveolar nerve (IAN) transposition for dental implant placement.MethodsThe study included seven consecutive patients who underwent IAN transposition surgery for the insertion of a dental implant into the atrophic posterior mandible. Of these, six patients (seven sides) were available for long-term assessment of postoperative IAN function. Neurosensory disturbance of the IAN was assessed objectively using the modified SW perception test reported by Semmes and Weinstein. In addition, the quality of nerve paralysis was assessed according to the criteria reported by Highet.ResultsThe median follow-up time was 49 months (range 12–105 months). No implant loss was observed during the follow-up. All patients experienced numbness immediately and the days after surgery. Complete recovery of neural function was observed on two sides; weak hypoesthesia was observed on two sides, moderate hypoesthesia on two sides, and severe hypoesthesia on one side. However, only one patient expressed concern about IAN function.ConclusionsIAN transposition is a useful method for placing implants in the atrophic posterior mandible. However, the procedure is complicated, with the possibility of some degree of neurosensory disturbance, although in most of our cases, it resolved within a clinically acceptable period.

Lateralization Technique and Inferior Alveolar Nerve Transposition.

Bone resorption of the posterior mandible can result in diminished bone edge and, therefore, the installation of implants in these regions becomes a challenge, especially in the presence of the mandibular canal and its contents, the inferior alveolar nerve. Several treatment alternatives are suggested: the use of short implants, guided bone regeneration, appositional bone grafting, distraction osteogenesis, inclined implants tangential to the mandibular canal, and the lateralization of the inferior alveolar nerve. The aim was to elucidate the success rate of implants in the lateralization technique and in inferior alveolar nerve transposition and to determine the most effective sensory test. We conclude that the success rate is linked to the possibility of installing implants with long bicortical anchor which favors primary stability and biomechanics.

Five-year follow-up of implants placed simultaneously with inferior alveolar nerve lateralisation or transposition

Introduction: The aim of this investigation was to evaluate the 5-year outcomes regarding presence of intraoperative and postoperative complications and the survival rate of implants placed simultaneously with lower alveolar nerve lateralization or transposition. Material and Methods: implants placement was performed on 34 patients with advanced atrophy of the posterior mandible simultaneously with lower alveolar nerve lateralization or transposition. Transposition was done only in two cases; in the rest of the cases lateralization of lower alveolar nerve was performed. Results: The survival rate at the end of the fifth year after implant placement was 100%. The mean height of residual bone at the region of implant placement was 2.76 mm. The mean marginal bone resorption for at the fifth year was 0.309 mm. In 20.6% of cases a positive BOP (bleeding on probing) was registered. 14.7% of the patients were free of symptoms of NSD (neuro-sensory dysfunction). In the rest of the patients the mean duration of NSD was 2.06 weeks. In 76.4% of patients the symptoms of NSD of nervus alveolaris inf. resolved after the second week. The maximum period of reported NSD was 6 weeks. No permanent NSD occured. Conclusion: Properly performed lateralization or transposition of the lower alveolar nerve is associated with minimal risk of permanent neuro-sensory dysfunction and providing an opportunity for placement of intraosseal implants in the posterior mandible with high survival rate.

Inferior alveolar nerve (IAN) transposition in a patient with multiple sclerosis – a report of a patient with 1‐year follow‐up

AbstractInferior alveolar nerve (IAN) transposition is a well‐known technique which utilises existing alveolar bone for implant placement in posterior mandible, thus avoiding additional procedures such as bone graft or ridge augmentation. Multiple sclerosis (MS) is a disorder affecting the myelin sheath of the nerve and causes varying degrees of sensory‐motor neural dysfunction. A case of a 55‐year‐old Caucasian female with MS undergoing IAN transposition for management of atrophic mandible is discussed here. At the end of 1 year, there was minimal residual sensory deficit, not affecting function.

Cortical Bone Augmentation Versus Nerve Lateralization for Treatment of Atrophic Posterior Mandible: A Retrospective Study and Review of Literature.

We sought to assess implant success/survival/failure rate following cortical autogenous tenting technique (CATT) versus inferior alveolar nerve transposition (IANT) in the posterior mandible. Patients who underwent these two procedures between 2007 and 2011 were analyzed. CATT was performed using lateral ramus block graft and implants were inserted simultaneously or after 4 to 6 months. In IANT, implants were placed simultaneously after nerve transposition with or without mental foramen involvement. Data regarding marginal bone level (MBL), pus discharge (PD), neurosensory dysfunction (NSD), implant mobility, and failure were collected. Success rate was measured based on Pisa Consensus. Independent sample t-test with a significance level of 0.05 was used to compare implant dimensions and MBL changes between the two techniques. A total of 118 patients with a mean age of 54.85 years were included. The mean follow-up after CATT and IANT was 37.97 and 18.51 months, respectively. The overall survival and success rates of dental implants in the CATT group were 98.73% and 71.52%, respectively. The corresponding values for IANT subjects were 98.74% and 94.56%, respectively. Implant length and diameter in IANT group were significantly longer and wider than implants used after CATT (p value < .001). MBL changes in both techniques were less than 1 mm (p value = .79). Two cases of NSD, seven PD, and two implant failures were found in the CATT group. For IANT patients, seven permanent NSD, two PD, two implant failures, and one mandibular fracture were documented. Both techniques had implant survival rates similar to implants placed in unaltered bone. A higher implant success rate, albeit with higher incidence of long-lasting nerve damage, was observed in the IANT group.

Inferior alveolar nerve lateralization and transposition for dental implant placement. Part I: a systematic review of surgical techniques.

ABSTRACTObjectivesThe purpose of this first part of a two-part series was to review the literature concerning the indications, contraindications, advantages, disadvantages and surgical techniques of the lateralization and transposition of the inferior alveolar nerve, followed by the placement of an implant in an edentulous atrophic posterior mandible.Material and MethodsA comprehensive review of the current literature was conducted according to the PRISMA guidelines by accessing the NCBI PubMed and PMC database, academic sites and books. The articles were searched from January 1997 to July 2014 and comprised English-language articles that included adult patients between 18 and 80 years old with minimal residual bone above the mandibular canal who had undergone inferior alveolar nerve (IAN) repositioning with a minimum 6 months of follow-up.ResultsA total of 16 studies were included in this review. Nine were related to IAN transposition, 4 to IAN lateralization and 3 to both transposition and lateralization. Implant treatment results and complications were presented.ConclusionsInferior alveolar nerve lateralization and transposition in combination with the installation of dental implants is sometimes the only possible procedure to help patients to obtain a fixed prosthesis, in edentulous atrophic posterior mandibles. With careful pre-operative surgical and prosthetic planning, imaging, and extremely precise surgical technique, this procedure can be successfully used for implant placement in edentulous posterior mandibular segments.