Surgical risk factors and maxillary nerve function after Le Fort I osteotomy

A prospective cohort study evaluating subjective and objective neurosensory changes following LeFort I osteotomy

INTRODUCTION

This study aimed to investigate the incidence and recovery of neurosensory deficit (NSD) after LeFort I osteotomy over 12 months and identify any association between age, gender, and extent of surgical movement on recovery. Furthermore, the study explored the relationship between objective and subjective outcome measures.

METHODS

A prospective cohort study consisting of 31 patients. Subjects were assessed at baseline, 1 week (T1), 1 month, 3 months, 6 months, and 12 months (T5) after LeFort I osteotomy. Objective assessment measures included pinprick (PP), static light touch (SLT), static 2-point discrimination (STPD), and electric pulp testing (EPT). Subjective reporting was undertaken using a visual analog scale. Patients rated the impact of NSD on intraoral and extraoral sites at the same time points as for objective measures.

RESULTS

Twenty-eight patients (16 females and 12 males) with a mean age of 24.5 years (standard deviation, 7.4) completed the study. There was a notable reduction in NSD from T1 (85.7%) to T5 (17.9%). No significant differences were found with respect to the influence of gender; PP (P = 0.06), SLT (P = 0.10), STPD (P = 0.65) and EPT (P = 0.19) or extent of surgical movement; PP (P = 0.50), SLT (P = 0.72), STPD (P = 0.06) and EPT (P = 0.74) on NSD. Age is a significant factor for intraoral NSD in the immediate postoperative period; PP (P < 0.0001) and SLT (P < 0.0001). Subjectively, patients reported a high degree of concern associated with NSD immediately after surgery with a gradual reduction from T1 to T5. There is a significant difference in subjective reporting between those with intraoral NSD than those with no intraoral NSD at 12 months (P = 0.031).

CONCLUSIONS

NSD is high after LeFort I surgery, particularly intraorally in the palate. At 12 months, the incidence of NSD is 17.9%. Recovery of NSD to a nonsignificant value from baseline takes up to 3 months for extraoral sites and between 3 and 6 months for intraoral soft tissues. The maxillary dentition continues to recover from NSD up to 12 months postsurgery. Age, gender, and extent of the surgical movement do not influence the extent of NSD at 12 months. Increasing age is associated with increased NSD at intraoral sites immediately after surgery. Intraoral NSD is more of a concern to patients than extraoral NSD. Patients' concerns associated with NSD reduced over time, demonstrating a degree of adaptation in the longer term.

Complications or rather side effects? Quantification of patient satisfaction and complications after orthognathic surgery-a retrospective, cross-sectional long-term analysis

OBJECTIVES

The aim of this clinical analysis was to evaluate intraoperative and early postoperative complications as well as late findings and the overall patient satisfaction following orthognathic surgery.

MATERIALS AND METHODS

In a retrospective, cross-sectional study, 119 patients after orthognathic surgery were included. Surgical approaches were single bilateral sagittal split osteotomy (BSSO (n = 52)), single LeFort-I osteotomy (n = 5) and bimaxillary osteotomy (LeFort-I + BSSO (n = 62)). Intraoperative and early (0-4 weeks postoperative) complications were investigated retrospectively (n = 119), whereas late findings and quality of life were assessed via clinical follow-up and survey (mean: 59 months postoperative) on 48 patients.

RESULTS

Bad split (n = 4/114) was the most common intraoperative complication followed by one case of severe bleeding. Regarding early postoperative complications, temporary damage of the inferior alveolar nerve after BSSO was most common (n = 33/114), followed by facial nerve dysfunction (n = 3), failed osteosynthesis (n = 2) and one case of postoperative dyspnoea. Permanent hypaesthesia of the lower lip was the most prevalent (n = 28/45^{(BSSO and LeFort-I + BSSO)}) late finding with varying extent, followed by temporomandibular dysfunction (TMD) (n = 25/48). Skeletal relapse mostly occurred after class II treatment, followed by class III, posterior crossbite and open bite. Overall, the surgery improved the patients' self-perception (85.4%), with 60.4% of patients opting for surgery again.

CONCLUSIONS

Long-term complications after orthognathic surgery occurred more frequently than commonly described in the literature, and analyses of the quality of life show the need for more comprehensive preoperative patient education.

CLINICAL RELEVANCE

Hypaesthesia of the lower lip presented less as complication but rather as side effect following BSSO. As orthognathic surgery is mostly elective, preoperative patient education is of pivotal importance and should include proactive risk stratification.

Anatomic Study of Accessory Infraorbital Nerves and Foramina: Application for a Better Understanding of Complications of Le Fort Fractures and Osteotomy

PURPOSE

Neurosensory disturbance of the infraorbital nerve is one of the many complications of the Le Fort osteotomy. An accessory infraorbital foramen (AIOF) can be one reason for such complications. Therefore, the purpose of the present study was to elucidate the distribution of the accessory infraorbital nerve (AION) arising from the AIOF.

MATERIALS AND METHODS

We dissected 60 sides from 30 fresh-frozen cadaveric heads.

RESULTS

An AIOF was found in 36.7% of the heads examined. When an AIOF was detected, the nerve was traced distally and proximally. The mean horizontal and vertical diameters of the AIOF were 1.64 ± 0.88 and 1.75 ± 0.87 mm, respectively. The largest AIOF was 3.42 × 3.79 mm. All AIOFs were located medial to the infraorbital foramen. Most of the AIONs (87.5%) had branches to the external nose.

CONCLUSIONS

The AION should always be remembered by surgeons to allow for improved outcomes and better understanding of the complications such as those occurring after Le Fort osteotomy.

Changes in pulp blood flow and pulp sensibility resulting from surgically assisted rapid maxillary expansion: A clinical study

INTRODUCTION

The aim of this work was to assess and compare changes in pulp blood flow (PBF) and pulp sensibility (PS) after surgically assisted rapid maxillary expansion (SARME) and rapid orthopedic maxillary expansion (OME).

METHODS

Ten patients requiring SARME and 10 requiring OME had the pulp status of their maxillary incisors and canines assessed with the use of laser Doppler flowmetry, electric pulp testing (EPT), and CO₂ snow. The SARME group was assessed at T1-S (before surgery), T2-S (after surgery, before expansion), T3-S (after surgery, at completion of expansion), and T4-S (3 months after surgery). The OME group was assessed at T1-O (before expansion), T2-O (after rapid expansion), and T3-O (3 months after expansion commencement). Relationships between PBF/PS and the procedures, assessment times, and tooth types were evaluated.

RESULTS

In the SARME group, surgery did not cause significant (P ≥0.05) reduction in PBF, maxillary expansion did cause significant (P ≤0.05) reduction in PBF, pretreatment PBF was reestablished by T4-S, and nonresponses to both EPT and CO₂ peaked at T2-S. In the OME group, rapid expansion caused significant (P ≤0.05) reduction in PBF, pretreatment PBF was reestablished by T3-O, and all teeth responded to at least 1 of EPT or CO₂ at each assessment time.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Within the study's limitations, it can be concluded that both SARME and OME induce reduction but not elimination of PBF to maxillary anterior teeth and therefore do not cause loss of pulp vitality; surgery for SARME does not significantly reduce PBF to maxillary anterior teeth, rather it is the process of maxillary expansion that significantly reduces PBF in SARME patients; and caution when using CO₂ and EPT tests alone to assess pulp status after SARME is warranted because the capacity for CO₂ or EPT to provide negative sensibility responses despite the presence of PBF was observed.

Quantitative sensory testing for assessment of somatosensory function in human oral mucosa: a review

OBJECTIVE

This narrative review provides an overview of the quantitative sensory testing (QST) to assess somatosensory function in human oral mucosa.

MATERIAL AND METHODS

A literature search was conducted in the PubMed database to identify studies in vivo on human oral mucosa using QST methods. A list of 149 articles was obtained and screened. A total of 36 relevant articles remained and were read in full text. Manual search of the reference lists identified eight additional relevant studies. A total of 44 articles were included for final assessment.

RESULTS

The included studies were divided into six categories according to the study content and objective. In each category, there was a great variety of aims, methods, participants and outcome measures. The application of QST has nevertheless helped to monitor somatosensory function in experimental models of intraoral pain, effects of local anesthesia, after oral and maxillofacial surgery and after prosthodontic and orthodontic treatment.

CONCLUSIONS

QST has been proved to be sufficiently stable and reliable, and valuable information has been obtained regarding somatosensory function in healthy volunteers, special populations and orofacial pain patients. However, as most of the studies were highly heterogeneous, the results are difficult to compare quantitatively. A standardized intraoral QST protocol is recommended and expected to help advance a mechanism-based assessment of neuropathies and other intraoral pain conditions.

Anatomic basis of Le Fort 1 impaction osteotomy: a radiological study

PURPOSE

In Le Fort 1 osteotomy when a maxillary impaction is necessary, surgeons have to face different anatomical problems. (1) To determine the best bone resection route, they have to consider the situation of dental roots, infraorbital foramen and maxillary artery. (2) In case of Le Fort 1 osteotomy combined with a mandibular sagittal split osteotomy, the palate has to be replaced in horizontal position although there is no anatomical landmark. (3) In case of Gummy smiles, it can be due to either long face or short upper lip. The main objective was to identify safe bony landmarks to perform a Le Fort I osteotomy and to find a reliable way for repositioning the palate horizontally; the secondary objective was to determine the upper lip normal length.

METHODS

The study was based on 178 facial CT examinations. The following parameters have been used: the vertical length of the upper lip, the vertical heights of the anterior nasal spine, the canine and molar roots, the inferior limit of the pterygomaxillary fossa and the vertical height of the infraorbital foramen on both sides.

RESULTS

The vertical length from the subnasal point to the upper vermilion was 15.06 ± 3.09 mm, and to the junction of the upper and lower lips was 23.94 ± 3.79 mm. The vertical length from the anterior nasal spine to the incisor alveolar border was 19.70 ± 3.17 mm. The height of the canine root was 17.11 ± 2.60 mm. The height of the highest lateral root of first or second maxillary molars was 11.71 ± 1.83 mm. The vertical length from the inferior limit of the pterygomaxillary fossa (pti point) to the alveolar border of the pterygomaxillary suture was 19.86 ± 3.45 mm. The height from the center of the infraorbital foramen to the alveolar border of the maxilla on a vertical line was not statistically different on right and left sides.

CONCLUSIONS

According to our results, in impaction Le Fort 1 osteotomy, the bone resection must pass 20 mm above the alveolar border in canine area, and 15 mm above the alveolar border in molar area. The resection has to end less than 20 mm above the inferior border of the pterygomaxillary suture. The vertical height of the infraorbital foramen is a consistent landmark for repositioning of the palate in a horizontal plane.

Orthognathic Surgery: Outcome in a Facebook Group

The literature shows that the indications for orthognathic surgery (OS) are often functional problems and unsatisfactory facial esthetics. This study investigated the esthetic outcomes and overall satisfaction following OS. Somatosensory change is a relatively common complication and its influence on the level of satisfaction was studied. The social-networking web site Facebook was used to identify the study population. An online questionnaire was performed using the website SurveyMonkey. In all, 105 (9%) respondents from the Danish Facebook group about OS, called Kaebeoperation (jaw surgery), were enrolled in the study. The respondents consisted of 12 men and 93 women, with a mean age of 27 ± 9 years. Fifty-four percent replied that esthetic concerns were the reason for the OS. Eighty-four percent reported improvement in facial esthetics after the OS. Men indicated a higher degree of improvement in beauty than women (P = 0.030). Sixty-four percent replied that their attractiveness had been increased after OS. Eighty-six percent were happy with the results and 89% would recommend the surgery to others in need. No significant differences in esthetic results and satisfaction were seen with regard to sex, age, and somatosensory change. High satisfaction and improvement in facial esthetic after OS were seen. Young patients (16-25 years) and men indicated a higher degree of satisfaction than old (>25 years) patients and women. The use of social media seems to be an interesting platform for qualitative scientific research in certain age groups. Further prospective and objective studies about the esthetic improvement after OS should be performed.

Preoperative, intraoperative, and postoperative complications in orthognathic surgery: a systematic review

Objectives

The aim of this study was to determine whether orthognathic surgery is associated with any complications, and what type of complications may occur.

Materials and methods

Data were obtained using PubMed (MEDLINE), ISI Web of Knowledge, Ovid, Cochrane Library, Embase Library, and an additional manual search. The titles and abstracts of the electronic search results were screened and evaluated by two observers for eligibility according to the inclusion and exclusion criteria.

Results

A total of 1924 articles were identified, and we retained 44 articles for the final analysis. The Prisma diagram flowchart demonstrates our selection scheme. For the purpose of this study, the Cochrane data extraction form was modified. One review author extracted data from the included studies, and the second author checked all of the forms. The hierarchy of evidence classification from the UK NHS Centre for Reviews and Dissemination was used to assess the level of evidence for the retrieved studies.

Conclusions

An evaluation of the obtained studies revealed the existence of a large number of varied complications associated with orthognathic surgery procedures.

Clinical relevance

Oral and maxillofacial surgeons, orthodontists, and the surgical team need to prevent such complications during preoperative, intraoperative, and postoperative periods to increase the safety of orthognathic surgery procedures. This review was registered on http://www.crd.york.ac.uk/PROSPERO as CRD42013004711.

Electronic supplementary material

The online version of this article (doi:10.1007/s00784-015-1452-1) contains supplementary material, which is available to authorized users.

Stimulation of the sphenopalatine ganglion (SPG) for cluster headache treatment. Pathway CH-1: a randomized, sham-controlled study

Background

The pain and autonomic symptoms of cluster headache (CH) result from activation of the trigeminal parasympathetic reflex, mediated through the sphenopalatine ganglion (SPG). We investigated the safety and efficacy of on-demand SPG stimulation for chronic CH (CCH).

Methods

A multicenter, multiple CH attack study of an implantable on-demand SPG neurostimulator was conducted in patients suffering from refractory CCH. Each CH attack was randomly treated with full, sub-perception, or sham stimulation. Pain relief at 15 minutes following SPG stimulation and device- or procedure-related serious adverse events (SAEs) were evaluated.

Findings

Thirty-two patients were enrolled and 28 completed the randomized experimental period. Pain relief was achieved in 67.1% of full stimulation-treated attacks compared to 7.4% of sham-treated and 7.3% of sub-perception-treated attacks (p < 0.0001). Nineteen of 28 (68%) patients experienced a clinically significant improvement: seven (25%) achieved pain relief in ≥50% of treated attacks, 10 (36%), a ≥50% reduction in attack frequency, and two (7%), both. Five SAEs occurred and most patients (81%) experienced transient, mild/moderate loss of sensation within distinct maxillary nerve regions; 65% of events resolved within three months.

Interpretation

On-demand SPG stimulation using the ATI Neurostimulation System is an effective novel therapy for CCH sufferers, with dual beneficial effects, acute pain relief and observed attack prevention, and has an acceptable safety profile compared to similar surgical procedures.

Evaluation of neurosensory alterations via clinical neurosensory tests following anterior maxillary osteotomy (Bell technique)

Neurosensory deficits are the most common complication following orthognathic surgery. Le Fort I and sagittal split ramus osteotomies have been widely studied but there is a lack of data about the neurosensory alterations resulting from anterior maxillary osteotomy (AMO). This paper evaluates the neurosensory alterations in cutaneous regions including lower eyelid, cheek, nose, upper lip and vestibular and palatal mucosal areas using simple clinical tests following AMO performed with Bell's incision so patients can be properly informed about the extent of sensory loss and its rate of recovery following AMO. Twenty-four sides of 12 patients (eight females; four males) with a mean age of 14.20 ± 1.86 years (range 12-17 years) were examined. Pin prick sensation, light touch sensation, static and dynamic two-point discrimination tests were used. Following AMO, vestibular mucosa, upper lip, nose and cheek were the most commonly affected sites. No alterations were detected in lower eyelid and palatal mucosa. The neurosensory deficits in cheek, nose and upper lip resolved 10 days after surgery. The vestibular mucosa showed normal sensation on day 30. In conclusion, following AMO, neurosensory alterations can occur, but it will resolve spontaneously in 30 days.

Verification of nerve integrity after surgical intervention using quantitative sensory testing

PURPOSE

The aim of this study was to apply a standardized Quantitative Sensory Testing (QST) approach in patients to investigate whether oral surgery can lead to sensory changes, even if the patients do not report any sensory disturbances. Furthermore, this study determines the degree and duration of possible neuronal hyperexcitability due to local inflammatory trauma after oral surgery.

PATIENTS AND METHODS

Orofacial sensory functions were investigated by psychophysical means in 60 patients (30 male, 30 female) in innervation areas of infraorbital nerves, mental nerves and lingual nerves after different interventions in oral surgery. The patients were tested 1 week, 4 weeks, 7 weeks, and 10 weeks postoperatively. As controls for bilateral sensory changes after unilateral surgery, tests were additionally performed in 20 volunteers who did not have any dental restorations.

RESULTS

No differences were found between the control group and the control side of the patients. Although not 1 of the patients reported paresthesia or other sensory changes postoperatively, QST detected significant differences between the control and the test side in the mental and lingual regions. Test sides were significantly less sensitive for thermal parameters (cold, warm, and heat). No differences were found in the infraorbital region. Patients showed significantly decreased pain pressure thresholds on the operated side. QST monitored recovery over time in all patients.

CONCLUSIONS

The results show that oral surgery can lead to sensory deficits in the mental and lingual region, even if the patients do not notice any sensory disturbances. The applied QST battery is a useful tool to investigate trigeminal nerve function in the early postoperative period. In light of the increasing forensic implication, this tool can serve to objectify clinical findings.

Guidelines and recommendations for assessment of somatosensory function in oro-facial pain conditions--a taskforce report

The goals of an international taskforce on somatosensory testing established by the Special Interest Group of Oro-facial Pain (SIG-OFP) under the International Association for the Study of Pain (IASP) were to (i) review the literature concerning assessment of somatosensory function in the oro-facial region in terms of techniques and test performance, (ii) provide guidelines for comprehensive and screening examination procedures, and (iii) give recommendations for future development of somatosensory testing specifically in the oro-facial region. Numerous qualitative and quantitative psychophysical techniques have been proposed and used in the description of oro-facial somatosensory function. The selection of technique includes time considerations because the most reliable and accurate methods require multiple repetitions of stimuli. Multiple-stimulus modalities (mechanical, thermal, electrical, chemical) have been applied to study oro-facial somatosensory function. A battery of different test stimuli is needed to obtain comprehensive information about the functional integrity of the various types of afferent nerve fibres. Based on the available literature, the German Neuropathic Pain Network test battery appears suitable for the study of somatosensory function within the oro-facial area as it is based on a wide variety of both qualitative and quantitative assessments of all cutaneous somatosensory modalities. Furthermore, these protocols have been thoroughly described and tested on multiple sites including the facial skin and intra-oral mucosa. Standardisation of both comprehensive and screening examination techniques is likely to improve the diagnostic accuracy and facilitate the understanding of neural mechanisms and somatosensory changes in different oro-facial pain conditions and may help to guide management.

Analysis of trigeminal nerve disorders after oral and maxillofacial intervention

Background

Quantitative sensory testing (QST) is applied to evaluate somatosensory nerve fiber function in the spinal system. This study uses QST in patients with sensory dysfunctions after oral and maxillofacial surgery.

Methods

Orofacial sensory functions were investigated by psychophysical means in 60 volunteers (30 patients with sensory disturbances and 30 control subjects) in innervation areas of the infraorbital, mental and lingual nerves. The patients were tested 1 week, 4 weeks, 7 weeks and 10 weeks following oral and maxillofacial surgery.

Results

QST monitored somatosensory deficits and recovery of trigeminal nerve functions in all patients. Significant differences (p < 0.05) between control group and patients were shown for cold, warm and mechanical detection thresholds and for cold, heat and mechanical pain thresholds. Additionally, QST monitored recovery of nerve functions in all patients.

Conclusion

QST can be applied for non-invasive assessment of sensory nerve function (Aβ-, Aδ- and C-fiber) in the orofacial region and is useful in the diagnosis of trigeminal nerve disorders in patients.