Sensory retraining after orthognathic surgery: Effect on patient report of altered sensations

Pre-Surgical Factors Influencing Post-Surgical Outcomes in Orthognathic Surgery Patients: A Longitudinal Study

Background/Objectives: This study aims to assess the relationship between physical and psychosocial pre-surgical factors and post-surgical evolution in patients undergoing orthognathic surgery. Methods: A cohort study with 3 months of follow-up after maxillofacial surgery was conducted. Participants were recruited from the Maxillofacial Surgery Unit of Hospital Universitario La Paz in Madrid, Spain. Primary variables included the range of motion of mouth opening, protrusion tongue force, anxiety, depression and kinesiophobia. Assessments were realised on-site or via video call. Statistical analysis was conducted using mixed-effects models. Results: The initial recruitment yielded 22 patients, with 19 ultimately eligible for analysis. The study found significant impacts of pre-surgical factors on post-surgical evolution. Both ranges of motion and anxiety showed influences from baseline measures, with the range of motion affected by a pre-surgical range of motion (estimate: 3.89) and positive expectations (estimate: 4.83). Anxiety was influenced by both pre-surgical (estimate: 0.48) and baseline anxiety levels (estimate: 0.64). Kinesiophobia demonstrated a trend toward significance, with baseline levels affecting post-surgical evolution (estimate: 0.77). Conclusions: Our results highlight the relationship between pre-surgical factors and post-surgical outcomes in orthognathic surgery patients. Pre-surgical range of motion and positive expectations were found to influence post-surgical range of motion, while pre-surgical anxiety levels impacted post-surgical anxiety evolution. Pre-surgical kinesiophobia also showed potential as a post-surgical kinesiophobia predictor, but further investigation is needed to confirm this relationship.

Effect of betamethasone injection into the pterygomandibular space on the neurosensory disturbance after bilateral sagittal split ramus osteotomy: a pilot study

AIM

The aim of this study was to evaluate the effect of local betamethasone injection into the pterygomandibular space on postoperative neurosensory deficits.

MATERIALS AND METHODS

A prospective controlled clinical study was conducted on 16 patients (6 male, 10 female; mean age, 24.95 ± 9.22 years) who underwent bilateral sagittal ramus osteotomy for mandibular discrepancies. One side of each patient's mandible was randomly selected as the control side, and the opposite side as the experimental side. On the experimental side, a solution of betamethasone (6 mg/1 ml) was injected into the pterygomandibular space after the completion of wound closure. Neurosensory tests, including light touch, two-point discrimination, direction of movement, thermal sensitivity, and pin-prick discrimination, were performed. The follow-up period ranged between 6 and 12 months, according to the particular sensory test. The Fisher exact test was used to analyse the data.

RESULTS

The light touch sensation was abnormal in 75% of the control side and 31% of the study side, with the difference being significant (p = 0.03). However, at 6 months, all the study cases regained touch sensation, compared to 69% of the control side. No significant difference in direction movement discrimination was seen; however, at 3 months, the study side showed significantly less direction sensation (19%) compared to the control side (56%) (p = 0.02). There was no significant difference in the two-point discrimination; however, at 3 months, the study side had a significantly less abnormal two-point sensation (13%) than the control side (56%) (p = 0.02). In addition, no significant difference was noted in thermal sensitivity or pin-prick sensation.

CONCLUSION

Betamethasone injection into the pterygomandibular space reduces neurosensory disturbances after bilateral sagittal split ramus osteotomies nd leads to faster recovery of sensations.

Oral Functional Behavior and Neurosensation After Adult Maxillomandibular Advancement for Obstructive Sleep Apnea in the Long-Term

PURPOSE

We evaluated and correlated the long-term subjective perioral neurosensory deficit intensity and oral functional behavior difficulty after maxillomandibular advancement (MMA) for adult obstructive sleep apnea (OSA).

PATIENTS AND METHODS

We implemented a long-term retrospective cohort study of adult subjects who had undergone MMA for OSA, with subjective assessments using 7-point visual analog scales. Adult subjects who had undergone MMA for OSA with a minimum of 5 years of follow-up data available who had agreed to participate were included in the present study. The 1-sample Wilcoxon signed rank test and Spearman correlation coefficients were used to evaluate the data. Statistical significance was set at the P < .05 level.

RESULTS

Of the 51 eligible subjects, 27 (53% response rate) were included in the present study. The mean age preoperatively was 59.8 years, with a mean follow-up of 12.7 years. Most subjects (85%) had, overall, reported the long-term subjective perioral neurosensory deficit intensity to be none to very mild (mode, 0; mean, 2.20; P < .05) and oral functional behavior to have none to very mild difficulty (mode, 0; mean, 1.6; P < .05). Statistically significant moderate to strong positive correlations between the subjective assessments of oral functional behavior and perioral neurosensory deficit intensity were found for chewing (r = 0.74), kissing (r = 0.50), eating (r = 0.80), speaking (r = 0.81), and drooling (r = 0.67).

CONCLUSIONS

Within the limitations of the present study, more than 12 years after MMA for severe OSA, most subjects (85%) had minimal to no subjective perioral neurosensory deficits and very minimal to no difficulty in the subjective assessment of oral functional behavior. Strong positive correlations between the subjective decreased perioral neurosensory deficit intensity and decreased oral function behavior difficulty suggest that the return of perioral neurosensation might contribute to the return of oral functional behavior.

Comparison of postoperative paresthesia after sagittal split osteotomy among different fixation methods: a one year follow-up study

Objectives

Postoperative paresthesia is a common complication after sagittal split osteotomy (SSO). This study aimed to compare paresthesia among different fixation methods one year postoperative.

Materials and Methods

This prospective cohort study assessed subjects in four groups: class II with miniplate fixation (Group 1), class II with three-screw fixation (Group 2), class III with miniplate fixation (Group 3), and class III with three-screw fixation (Group 4). Paresthesia was evaluated one year postoperative based on a 0-10 visual analogue scale. Pearson correlation was used to evaluate associations of age and mandibular movement with paresthesia. ANOVA was used to compare paresthesia among groups.

Results

A total of 80 subjects were enrolled, with 20 subjects in each of the four groups. The Pearson correlation test demonstrated a significant correlation between mandibular movement and paresthesia (P=0.001). Comparison of paresthesia among the groups showed significant differences among groups 1 and 2, 2 and 3, and 3 and 4 (P<0.05).

Conclusion

The three-screw fixation method led to more paresthesia one year postoperative compared with miniplate fixation. In addition, the magnitude of mandibular movement had a positive correlation with paresthesia.

Does Sensory Retraining Improve Subjective Rating of Sensory Impairment after Bilateral Sagittal Split Osteotomy?

Background:

Sensory retraining could ameliorate neurosensory disturbance (NSD) resulting from the injury of the inferior alveolar nerve after a bilateral sagittal split osteotomy (BSSO). The aim of this study was to measure the effects of sensory retraining on NSD.

Methods:

A randomized, prospective, single-blinded clinical trial was conducted on consecutive patients with NSD resulting from a BSSO to correct skeletal class III malocclusion. The outcome measurement of sensory recovery was performed using a patient-centered survey assessed by the total score of questionnaire (TSQ) and visual analogue scale (VAS) at preoperation (T0), 1 week after surgery (T1), each month from 1 to 6 months after surgery (T2–T7), and 1 year after surgery (T8).

Results:

In total, 115 consecutive patients were randomized into a control group (56 patients without sensory retraining) or study group (59 patients with sensory retraining). TSQ and VAS values continually decreased from T1 to T8 in both groups. The study group tended to have lower, but not significantly lower, TSQ and VAS values than the control group at each postoperative time point. Women and men responded similarly to sensory retraining at each time point. The oldest patients did not respond well to sensory retraining, compared with the youngest patients, from T1 to T8, and this age effect evaluated by the VAS reached a significant difference at T7 and T8.

Conclusion:

NSD, assessed by the TSQ and VAS, continually decreased over time after the BSSO. Sensory retraining could improve NSD, but not significantly.

Influence of Electroacupuncture and Laser-Acupuncture on Treating Paresthesia in Patients Submitted to Combined Orthognathic Surgery and Genioplasty

Objective: The goal of this research was to observe the influence of electroacupuncture (EA) and laser-acupuncture on the return of tactile/pain sensitivity in patients who underwent orthognathic surgery. Materials and Methods: Thirty volunteers subjected to orthognathic surgery were evaluated and randomly divided into 2 groups, in which 3 treatments were evaluated: control (n = 30) (G0, medication + placebo laser treatment) and 2 experimental treatments (n = 15) (G1, medication + EA) or G2 (medication + laser-acupuncture). The control group had n = 30 because for each experimental treatment conducted on a volunteer's hemi-face, there was a control treatment on the other hemi-face. In G1, medication was given with EA, with needles placed at predetermined points (ST 4 [Dicang], M-HN-18 [Jiachengjiang], CV 24 [Chengjiang], ST 5 [Daying], ST 6 [Jiache], and point A1 [YNSA]). For electrostimulation, the device used delivered transcutaneous electrical nerve stimulation of a burst type, with intensity and frequency variations of T = 220 ms and F = 4 Hz (30 minutes, 2 × /week). In G2, in addition to the medication, laser irradiation (at 780 nm) was applied on acupuncture points (at 0.04 cm², 70 mW, 6 s/point, 0.42 J/point, 10 J/cm², 2 × /week). All volunteers were evaluated before and during the 4 months following the surgery. Tactile sensitivity was assessed by mechanical brushing (brush #s 2 and 12) and by a 2-point discrimination test, using a bow compass. A pain test was performed with a pulp electrical test that stimulates intact nerves of the dentin-pulp complex. A Kaplan-Meier test was performed, and survival curves were plotted for comparison between groups. Cox regression analysis was also conducted (α = 0.05). Results: There were no statistically significant differences among the groups for the 2-point discrimination test (brushes #2 and #12) on the buccal mucosa region and for the pulp test on all evaluated regions. However, the tactile test using brush #12 revealed significant differences between G1 and the other groups when considering the lower lip (P = 0.024) and chin (P = 0.028) areas. Conclusions: Only EA was able to influence-using the brushing test (brush #12)-the return of tactile sensitivity on the chin and lower lip positively after combined orthognathic surgery and genioplasty.

Anterior projection of the maxillomandibular soft tissue complex after surgical correction of maxillary hypoplasia: a Scottish perspective

After orthognathic surgery the forehead remains unchanged. To produce facial harmony, the planned projection of the maxillomandibular complex must be placed in the correct relations to the unchanged position of the forehead. We have compared the anterior soft tissue projection of the maxillomandibular complex relative to the forehead after Le Fort I advancement surgery for correction of maxillary hypoplasia with that of a local reference group chosen by lay assessors. We retrospectively studied 32 patients (16 men and 16 women) all of whom had previously been treated by Le Fort I maxillary advancement. In addition a panel of 8 lay assessors selected a reference group of 24 women and 16 men. Standard profile photographs were taken, and horizontal measurements made, of several landmarks from a true vertical line (TV) passing through glabella. Together with facial harmony values these were compared between the groups. The orthognathic group had significantly more anterior mandibular projection relative to the forehead than the female reference group (p=0.03). As a result half of the horizontal harmony values were smaller in the orthognathic group. For men the position of the mandible, particularly the chin, was acceptable even though it was positioned more anteriorly. We have provided values for maxillomandibular projection derived from lay assessors and identified areas where differences from those of a reference group were detected. The projection of the mid and lower face of the local reference group to the forehead should guide preoperative planning.

Systematic review of preoperative mandibular canal position as it relates to postoperative neurosensory disturbance following the sagittal split ramus osteotomy

The purpose of this study was to review the current literature for the relationship between the preoperative position of the mandibular canal on three-dimensional (3D) radiographic imaging and postoperative neurosensory disturbance (NSD) following a sagittal split ramus osteotomy (SSRO). A literature search was conducted using PubMed, EMBASE, and the Cochrane Database for articles published from 1 January 2000 through 31 December 2013. Studies that included preoperative 3D imaging and assessment of NSD after surgery were reviewed. Study sample characteristics and results were extracted. Of the 69 articles identified, seven met the inclusion and exclusion criteria. There was no standardization for measuring the canal position or for evaluating NSD. General consensus was that the less space between the mandibular canal and the outer border of the buccal cortex the more frequent the occurrence of NSD. Increased bone density also appeared to contribute to a higher incidence of NSD. Utilization of 3D images to locate and measure the position of the mandibular canal is not standardized. Advances in 3D imaging and evaluation tools allow for new methodologies to be developed. Early attempts are informative, but additional studies are needed to verify the relationship between the location of the nerve and NSD following surgery.

Therapeutic effects of local application of dexamethasone during bilateral sagittal split ramus osteotomy surgery

PURPOSE

Bilateral sagittal split ramus osteotomy (BSSO) is one of the most common procedures used in the treatment of mandibular deformity. One common complication of this surgical procedure is hypoesthesia of the inferior alveolar nerve. The authors hypothesized that perioperative local application of dexamethasone would have positive therapeutic effects on neurosensory function.

MATERIALS AND METHODS

This study investigated 18 patients (10 male, 8 female; mean age, 26.1 ± 4.9 yr) who underwent BSSO. One side of each patient's mandible was randomly selected as the control side and the opposite side as the experimental side. A solution of dexamethasone 4 mg/1 mL was drawn into a syringe and poured directly on the distal segment of the exposed inferior alveolar nerve during splitting and 1 mL was poured on the same nerve immediately before the start of fixation. Neurosensory tests, including light touch, direction of movement, static 2-point touch, thermal stimuli, and pin prick discrimination, were conducted. The χ(2) and Fisher exact tests were used to evaluate the data.

RESULTS

The difference between the control and experimental groups at all intervals was not significant for any of the neurosensory tests.

CONCLUSION

Local application of dexamethasone on the exposed inferior alveolar nerve during BSSO is not recommended.

Influence of osteotomy procedure and surgical experience on early complications after orthognathic surgery in the mandible

INTRODUCTION

This study evaluated the influence of osteotomy procedure and surgical experience on early complication rates following orthognathic surgery in the mandible.

MATERIALS AND METHODS

In a retrospective study, patients who underwent a mandibular osteotomy (Obwegeser-Dal Pont (ODP) and Hunsuk-Epker (HE)) were included. Incidence of "bad splits", "bleeding episodes", "delayed wound healing", "failed osteosynthesis" and "nerve lesions" at 2 months post-operatively were recorded. Surgical experience was classified as: beginner (<10), intermediate (10-40) and expert (>40). Complications were correlated to the surgical approach and the experience level of the surgeon.

RESULTS

400 patients were included. 200 underwent a bimaxillary approach. 186 patients were operated using the ODP technique, 214 according to HE. Multivariate analysis confirmed significantly more unwanted fractures and bleeding events for ODP when compared to HE (p = 0.28, p = 0.003). Experienced surgeons had more osteosynthesis failures (0.047) and significantly more nerve lesions than the other groups (p = 0.01).

DISCUSSION

The HE osteotomy showed a more reliable fracture mechanism with less relevant bleeding episodes. Differences between the surgeons of varying training status were marginal with exception of a higher rate of osteosynthesis failure and temporary hypoesthesia in the experienced group.

Orthognathic and TMJ surgery: postsurgical patient management

Postsurgical patient management is a critical factor for high-quality patient treatment and predictable outcomes in orthognathic and temporomandibular joint (TMJ) surgery. Lack of understanding of proper patient management on the part of the surgeon and orthodontist can result in compromised or even disastrous results. Surgeons and orthodontists must have the knowledge and ability to implement postsurgical management protocols and strategies to provide the best care and outcomes possible for their orthognathic and TMJ surgery patients. Information is presented here in reference to postsurgical orthodontics, healing process, dietary considerations, activities, and potential complications to aid the clinician in understanding the postsurgical processes that patients will encounter.

Sensory retraining: a cognitive behavioral therapy for altered sensation

Sensory retraining teaches the patient to ignore or blot out postinjury unpleasant orofacial sensations to optimally tune into and decipher the weakened and damaged signals from the tissues. Sensory retraining is a simple, inexpensive, noninvasive exercise program, which initiated shortly after injury, can lessen the objectionable impression of orofacial altered sensations. Sensory retraining exercises are most effective on decreasing the perceived burden associated with hypoesthetic orofacial altered sensations.

Inferior alveolar nerve injury following orthognathic surgery: a review of assessment issues

The sensory branches of the trigeminal nerve encode information about facial expressions, speaking and chewing movements, and stimuli that come into contact with the orofacial tissues. Whatever the cause, damage to the inferior alveolar nerve negatively affects the quality of facial sensibility as well as the patient's ability to translate patterns of altered nerve activity into functionally meaningful motor behaviours. There is no generally accepted, standard method of estimating sensory disturbances in the distribution of the inferior alveolar nerve following injury. Assessment of sensory alterations can be conducted using three types of measures: (i) objective electrophysiological measures of nerve conduction, (ii) sensory testing (stimulus) measures and (iii) patient report. Each type of measure with advantages and disadvantages for use are reviewed.

Sensory retraining: burden in daily life related to altered sensation after orthognathic surgery, a randomized clinical trial

OBJECTIVE

Assess the long-term effect of sensory retraining exercises, age, gender, type of surgery, and pre-surgical psychological distress on patients' perception of the interference related to altered sensation 2 years after orthognathic surgery.

SETTING AND SAMPLE POPULATION

A total of 186 subjects with a developmental dentofacial disharmony were enrolled in a multicenter randomized clinical trial: one center was a community-based practice and the other a university-based center.

METHODS AND MATERIALS

Subjects were randomly allocated to two groups: standard of care mouth opening exercises after BSSO or a progressive series of sensory retraining facial exercises in addition to the opening exercises. At 1, 3, 6, 12, and 24 months after surgery, subjects scored unusual feelings on the face, numbness, and loss of lip sensitivity from 'no problem (1)' to 'serious problem (7)'. A marginal proportional odds model was fit for each of the ordinal outcomes.

RESULTS

Up to 2 years after surgery, the opening exercise only group had a higher likelihood of reporting interference in daily activities related to numbness and loss of lip sensitivity than the sensory retraining exercise group. The difference between the two groups was relatively constant. Older subjects and those with elevated psychological distress before surgery reported higher burdens related to unusual facial feelings, numbness, and loss of lip sensitivity (p < 0.02).

CONCLUSION

The positive effect of sensory retraining facial exercises observed after surgery is maintained over time. Clinicians should consider the patient's age and psychological well-being prior to providing pre-surgical counseling regarding the impact on daily life of persistent altered sensation following a mandibular osteotomy.