Neurosensory Disturbance of the Inferior Alveolar Nerve After Bilateral Sagittal Split Osteotomy: A Systematic Review

doi:10.1016/j.joms.2007.05.009

Journal of Oral and Maxillofacial Surgery

Volume 65, Issue 9, September 2007, Pages 1707-1715

https://doi.org/10.1016/j.joms.2007.05.009 Get rights and content

Purpose

The evaluation of neurosensory disturbance of the inferior alveolar nerve (IAN) can be performed by purely subjective, relatively objective, or purely objective methods. The aim of this study was to provide a systematic review of the incidence of inferior alveolar nerve sensory disturbance after bilateral sagittal split osteotomy, as well as the frequency of recovery of sensory function using objective methods of evaluation only.

Materials and Methods

Searches were conducted employing MEDLINE, Scirus, and the Cochrane Central Register of Controlled Trials (CENTRAL). Seven studies were included in this review.

Results

This systematic review has shown that the frequency of nerve impairment evaluated by subjective methods was higher than that indicated by studies adopting objective methods at each time of follow-up considered. In particular at the seventh postoperative day the frequency obtained using the objective methods was 63.3% while that obtained with subjective methods was 83%. At 1 year follow-up a frequency of sensory impairment of 12.8% was obtained using objective methods and a frequency of 18.4% when subjective methods were used. The data were analysed using the index of inter-rater reliability (Cohen’s Kappa) with the degree of nerve damage evaluated by objective methods considered the “gold standard.” The value of Cohen’s Kappa at 1 week follow-up is 0.53; at 1 year follow-up it increased to 0.90.

Conclusions

On the basis of these results, objective methods provide the most sensitive diagnostic tests at early controls—within 3 months of the operation. At later control points the sensitivity increases and the inter-rater reliability is satisfactory.

Section snippets

Materials and Methods

A thorough review of the relevant literature linking BSSO with neurological complications and objective testing methods was performed. Searches were conducted employing PubMed (www.pubmed.gov), MEDLINE (http://search.medscape.com/medline-search), Scirus (http://www.scirus.com), and the Cochrane Central Register of Controlled Trials (CCTR) (http://www.ovid.com/site/products/ovidguide/cctrdb.htm). The search terms used were: orthognathic surgery neurological complications, bilateral sagittal

Results

The PubMed search identified 147 studies on this subject. From the 147 studies initially obtained from the search 28 full-text articles were screened, of which 21 were not relevant and were excluded and 7 were considered eligible for inclusion in the review. The Scirus search identified 89 results, of which 26 were Web results and 59 were journal results; of the 59 studies obtained the full text of 5 were screened. Three studies were not relevant and were excluded and only 2 were included in

Discussion

Various methods have been adopted to test the function of the IAN after nerve lesion, from patient questioning6, 11, 12, 13, 14 to sophisticated neurosensory testing. In earlier studies, the diagnosis of IAN disturbance was based on the subjective report of the patient and clinical sensory tests. Subjective factors on the part of both the patient and the examiner contribute to the results, the reason why lack of objectivity is one of the problems associated with the use of clinical examination

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How do I expose the inferior alveolar nerve for microneurosurgical repair?
2024, Oral and Maxillofacial Surgery Cases
This technical note describes an innovation that addresses a clinical problem in iatrogenic inferior alveolar nerve (IAN) repair. The options for IAN exposure (Miloro, 1995) are less than ideal since they offer limited access and visibility and/or the exposure itself has a risk of inducing iatrogenic IAN injury. This technical note offers the option to perform IAN exposure via a unilateral sagittal split osteotomy (SSO). There are inherent risks of mild transient IAN paresthesia, malocclusion, bad splits, and the additional cost of rigid fixation hardware (Peleg et al., 2021). The significance of this technique is that it permits wide access for IAN reconstruction in cases where the IAN injury is in the posterior mandible (eg. due to mandibular third molar removal) where another option for access is limited. This technique will improve patient care by facilitating IAN exposure and repair. There should be no challenges or delays to implementing this innovation for surgeons who perform orthognathic surgery and nerve repair.
Risk factors of neurosensory disturbances at 1 year postoperatively after bilateral sagittal split osteotomy
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To investigate morphologic and surgical risk factors causing neurosensory disturbances (NSDs) after bilateral sagittal split osteotomy (BSSO).
A total of 237 patients (with 474 sides) who underwent BSSO were followed up for 1 year. Parameters examined included age, sex, asymmetry, mandibular movement direction, mandible cutting devices, split type, intraoperative exposure of the inferior alveolar nerve (IAN), contact between the IAN and screw, distance between mandibular canal and inner surface of the cortical bone (distance A), distance from lateral osteotomy to mental foramen (distance B), and NSD at 1 year postoperatively.
NSD was observed in 62 (13.1%) sides of 51 patients. Exploratory factor analysis determined 4 factors (factor 1: distance A; factor 2: direction of mandibular movement; factor 3: distance B and cutting devices; factor 4: IAN exposure). Logistic regression analysis was performed using the above factors and age, sex, and asymmetry, making a total of 7 variables. Age, factor 1, and factor 4 were significant predictors of NSD.
Advanced age, close distance between mandibular canal and inner surface of the cortical bone, and IAN intraoperative exposure are risk factors for NSD 1 year postoperatively. Cases at high risk for NSD must be treated with great care.
Effect of modified bilateral sagittal split osteotomy on inferior alveolar nerve neurosensory disturbance
2022, British Journal of Oral and Maxillofacial Surgery
Citation Excerpt :
Objective and subjective assessments of IAN neurosensory disturbance have been found to correlate well.16 Currently, no standard method of assessment is generally accepted,15 but subjective methods have been associated with a higher incidence of IAN neurosensory disturbance than objective methods.17 Patient satisfaction and quality of life are based on subjective perceptions and not on objective neurosensory tests.18
The aim of this study was to assess the occurrence of neurosensory disturbance of the inferior alveolar nerve (IAN) following modified mandibular bilateral sagittal split osteotomy (BSSO) that preserves the mandibular inferior border. All patients undergoing BSSO, associated or not with a Le Fort I osteotomy (performed by the same senior operator) between January 2018 and December 2019, were eligible. The modified BSSO consists of a modification of the technique described by Epker: the bony section of the buccal cortex stops 3-4 mm above the basal mandibular edge. While respecting the basilar border, sectioning is then performed up to the gonial angle where bicortical section is finally performed. Sensibility of the labial and chin area was evaluated immediately postoperatively, and at six months and two years of follow up. A total of 140 eligible patients underwent the modified BSSO between January 2018 and December 2019, and 72 were included. Hypoaesthesia was found in 81.9% of the patients (59/72 patients) at initial evaluation. It decreased to 45.8% (33/72 patients) at the six-month examination and to 12.5% (9/72 patients) at the last examination. Four bad splits were recorded. The modified BSSO preserves the inferior border of the mandible and maintains the IAN in the lingual fragment. There is no need to release the IAN, hence its manipulation is reduced and the incidence of IAN postoperative hypoaesthesia is also reduced.
Radiologic Risk Factors for Persistent Mandibular Nerve Neurosensory Disturbance Following Sagittal Split Osteotomy
2022, Journal of Oral and Maxillofacial Surgery
Neurosensory disturbance (NSD) occurring in the lower lips and chin is a major postoperative complication related to bilateral sagittal split osteotomy (SSO). The purpose of this study is to identify preoperative radiographic findings following SSO procedure associated with persistent NSD.
This retrospective cohort study analyzed data for consecutive patients who underwent SSO. Primary predictor variables, including ramus width, mandibular body height, mandibular angle length, gonial angle, distance from mental foramen to distal aspect of mandibular second molar (MFD), and measurement of bone marrow space (BMS), were examined in a series of radiographic images. The primary outcome variable was NSD. Patients with NSD were divided into 2 groups based on findings obtained 1 year postoperatively: persistent, for those with NSD remaining after 1 year, and transient, when NSD occurred for less than 1 year. Covariates included sex and age. Comparisons were analyzed by use of Mann-Whitney U test or χ² test. Multivariate analysis was performed using step-wise logistic regression to determine significant factors related to persistent NSD. A P value .005 or less was considered statistically significant.
Of the 349 sides investigated, the persistent NSD group consisted of 59 sides (16.9%), while the transient NSD group consisted of 290 sides (83.1%). The occurrence of persistent NSD was correlated with age (P < .05), MFD (P < .001), mandibular body height (P < .05), and BMS (P < .001). Multivariate logistic analysis also showed a significant association of MFD (P < .001) and BMS (P < .001).
Preoperative MFD and BMS are radiographic findings that are associated with an increased risk for persistent NSD following SSO procedure.
Extraoral vertical ramus osteotomy combined with internal fixation for the treatment of mandibular deformities
2022, British Journal of Oral and Maxillofacial Surgery
Extraoral vertical ramus osteotomy (EVRO) is used in orthognathic surgery for the treatment of mandibular deformities. Originally, EVRO required postoperative intermaxillary fixation (IMF). EVRO has been developed using rigid fixation, omitting postoperative IMF. We examined retrospectively the long-term stability and postoperative complications for patients with mandibular deformities who underwent EVRO with internal rigid fixation. Patients who were treated with EVRO for a mandibular deformity in the period 2008–2017 at the Clinic of Oral and Maxillofacial Surgery, Mölndal, Sweden were included (N = 26). Overjet and overbite were calculated digitally and cephalometric analyses were performed preoperatively, and at three days, six months, and 18 months postoperatively. There was a general setback of the mandible, decreased gonial angle and reduced degree of skeletal opening. Excellent dental and vertical skeletal stabilities were seen up to 18 months postoperatively, although relapse was seen sagitally up to six months postoperatively. Since the overjet did not show any significant change over time, the sagittal skeletal changes have been attributed to dental compensation. There was no permanent damage to the facial nerve and 5.8% neurosensory damage to the inferior alveolar nerve was observed.
Penetration of inferior alveolar nerve canal increased by bicortical fixation after bilateral sagittal split osteotomy in mandibular prognathism
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The purpose of this three-dimensional cone beam computed tomography (CBCT) study was to identify the difference between monocortical fixation (MCF) and bicortical fixation (BCF) in mandibular canal penetration after bilateral sagittal split osteotomy (BSSO) to correct mandibular prognathism, where interosseous fixation was done by BCF or MCF. CBCT was performed 1 week postoperatively and Dolphin 3D software was used to assess direct penetration of the mandibular canal by either type of screw. The primary outcome variable was the presence or absence of mandibular canal penetration and was categorized as a binary coded variable. The BCF and MCF groups were compared by χ² test, and the odds ratio for canal penetration was estimated. Multiple logistic regression was performed to identify factors related to canal penetration. A total of 118 patients were included. The MCF group had only 6% canal penetrations (3/50 patients) and the BCF group had 58.8% canal penetrations (40/68 patients). The regression model showed that BCF was the only factor causing mandibular canal penetration, with an adjusted odds ratio of 52.5. Awareness of the increased risk of canal penetration with BCF and potential nerve injury might influence case selection.

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Basic and patient-oriented researchNeurosensory Disturbance of the Inferior Alveolar Nerve After Bilateral Sagittal Split Osteotomy: A Systematic Review

Purpose

Materials and Methods

Results

Conclusions

Section snippets

Materials and Methods

Results

Discussion

Oral Surg Oral Med Oral Pathol Oral Radiol Endod

Br J Oral Maxillofac Surg

J Craniomaxillofac Surg

Br J Oral Maxillofac Surg

Int J Oral Maxillofac Surg

Int J Oral Maxillofac Surg

J Oral Maxillofac Surg

J Oral Maxillofac Surg

J Oral Maxillofac Surg

Br J Oral Maxillofac Surg

Br J Oral Maxillofac Surg

J Oral Maxillofac Surg

J Oral Maxillofac Surg

Basic and patient-oriented research
Neurosensory Disturbance of the Inferior Alveolar Nerve After Bilateral Sagittal Split Osteotomy: A Systematic Review