Health-related quality of life, jaw function and sleep-disordered breathing among patients with dentofacial deformity

BACKGROUND AND OBJECTIVES

Patients with dentofacial deformity (DFD) requiring orthognathic treatment have poor aesthetics, jaw function and psychological well-being, which potentially affect the quality of life. This study aimed to investigate the health-related general, oral and orthognathic quality of life, jaw function and sleep-disordered breathing at different stages of orthognathic surgical treatment.

METHODS

A total of 120 consecutive patients with DFD were recruited and grouped as pre-orthodontic treatment (group 1), pre-surgery (group 2), 4 months post-surgery (group 3), 24 months post-surgery (group 4) and in addition 30 controls without DFD (group 0). Outcomes were assessed using general health Short Form Survey (SF-36), Oral Health Impact (OHIP-14), Orthognathic Quality of Life Questionnaire (OQLQ), STOP-Bang and Jaw Function Limitation Scale (JFLS) questionnaires. In addition, presence or absence of pain was recorded. Data were tested with analysis of variance, Kruskal-Wallis test, Tukey post hoc test and structural equation modelling (SEM).

RESULTS

Results revealed SF-36 (p = .814) and STOP-Bang (p = .143) total scores did not differ between control and treatment groups. In contrast, OHIP-14, OQLQ and JFLS total scores differed between groups (p = .001). Higher scores were observed in groups 1 (p = .001), 2 (p = .001) and 3 (p = .041) compared to group 0, indicating poor oral health in patients with DFD. Importantly, in group 4, oral health-related quality of life was better, and OHIP-14 (p = .936) and JFLS (p = .572) scores did not differ from controls. OQLQ scores of group 4 were significantly lower than group 1 (p = .001) but higher than group 0 (p = .013). SEM results revealed a significant negative associations of pain with JFLS and OQLQ; OHIP-14 with OQLQ; OHIP-14 with SF-36; and finally STOP-Bang with SF-36. Positive associations were observed between JFLS and OHIP-14; OHIP-14 and OQLQ.

CONCLUSION

Oral health-related quality of life and jaw function appears to be improved 24 months after orthognathic surgery. Pain and limitation in jaw function had a negative association with health-related quality of life.

Do Patients Detect Changes in Breathing After Orthognathic Surgery?

BACKGROUND

Orthognathic surgery addresses facial aesthetics and function in patients with dentofacial deformities. It is associated with changes in upper airway volume (UAV). If changes in UAV are perceived by asymptomatic patients is unclear.

PURPOSE

The purpose was to measure associations between changes in UAV and patient-reported benefits using patient-reported outcome measures.

STUDY DESIGN

A sample presenting dentofacial deformities without reported breathing problems undergoing orthognathic surgery was retrospectively studied. Patients aged 18-30 years with 12-month follow-up were included. Patients with systemic disease, drug abuse, mental health disorder, or temporomandibular joint dysfunction were excluded.

PREDICTOR

The predictor variable was changes in UAV measured in 3-dimensional computed tomography. Subjects were grouped into increased or decreased UAV.

MAIN OUTCOME VARIABLE

The primary outcome variable was changes in health-related quality of life measured with Oral Health Impact Profile 49 (OHIP-49).

COVARIATES

Weight, height, age, sex, and sub-scaled OHIP-49 were registered. Cephalometric measurements of hard tissue movements were recorded.

ANALYSES

Mean, standard deviation, and a level of statistical significance at P < .05 were used. Differences in OHIP-49 were compared using unpaired t-test. The correlation between covariates and outcomes was analyzed using the Spearman's rank test. Analysis of covariance between the predictor and outcome, adjusted for covariates (body mass index), was performed.

RESULTS

Fifty-four subjects with a mean age of 20.89 years and 52% males were enrolled. The mean change in UAV was 0.12 cm3 (standard deviation [SD] 9.21, P = .93) with a mean absolute deviation of 7.28 cm3 (SD 5.54). The mean change in OHIP-49 score was 20.93 (SD 28.90). Twenty-seven (50%) subjects had increased UAV (7.4 cm3, SD 6.13) and the other had decreased (-7.17 cm3, SD 5.01) (P = .01). At follow-up, equal levels of mean OHIP-49 score were found, but because of a baseline difference (15.74, P = .048), the subjects with and without increased UAV improved in OHIP-49 score 13.04 (SD 30.53) and 28.81 (SD 25.33), respectively (P = .04).

CONCLUSIONS

Because equal levels of OHIP-49 score at follow-up, changes in UAV could not be associated with patient-reported health-related quality of life. Patient-reported outcome measure evaluations of orthognathic surgical treatment for airway obstruction should be performed in patients with a perceived impairment.

Outcome measures of the surgery first approach for orthognathic correction of dentofacial deformities

In the surgery-first approach (SFA), orthognathic surgery is performed without the need for presurgical orthodontic treatment. This study was aimed at assessing the treatment durations and occlusal outcomes for a consecutive cohort of patients, with a range of dentofacial deformities, who had completed orthognathic treatment using SFA. The duration of orthognathic treatment was measured. The overall change in occlusion, and the quality of the final occlusion, were evaluated using the patients' study casts. A single, independent, calibrated operator carried out the occlusal scores, using the validated Peer Assessment Rating (PAR) index. This was repeated to test intraoperator reliability. A total of 51 patients completed surgery-first treatment during the study period. The mean (range) age at surgery was 23.3 (15-47) years. The pre-treatment skeletal jaw relationship was Class III in 39 cases, and Class II in 12 cases. The mean (SD) overall treatment duration was 11.7 (5.7) months. The intraexaminer reliability of assessing the occlusion was high. The PAR scores confirmed a significant improvement in the quality of occlusion at the completion of treatment, which compares favourably with previous studies on the conventional orthodontics-first approach. The surgery first approach can be effective at correcting both Class II and Class III malocclusion types with reduced treatment times.

Surgery-First Orthognathic Approach for Correction of Dentofacial Deformity in Unilateral Cleft Lip and Palate

BACKGROUND

Although several studies have reported the advantages of the surgery-first approach for orthognathic correction of class III deformity, there is no report of the success of this approach for patients with cleft lip and palate. Therefore, the purpose of this study was to evaluate the stability and outcome of bimaxillary surgery for cleft-related dentofacial deformity using a surgery-first approach.

METHODS

Forty-one patients with unilateral cleft lip and palate who consecutively underwent Le Fort I and bilateral sagittal split osteotomies for skeletal class III deformity were included. Cone-beam computed tomographic scans before surgery, 1 week after surgery, and after orthodontic treatment were used to measure the surgical and postsurgical changes in jaw position by landmarks, and outcomes of jaw protrusion and relation, incisor angle and occlusion, and menton deviation after treatment. Self-report questionnaires regarding satisfaction with overall appearance of the face and seven facial regions were administered after treatment.

RESULTS

A clinically insignificant relapse was found in the maxilla (<1 mm) and mandible (<2 mm). There was a significant improvement in the jaw protrusion and relation, incisor angle and occlusion, and menton deviation. Responses from the self-report questionnaires completed after treatment indicated that patient satisfaction was high.

CONCLUSION

These findings demonstrate surgical-orthodontic treatment with a surgery-first approach can successfully improve cleft-related dentofacial deformity in patients with unilateral cleft lip and palate.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Impact of patient age on the functional and psychosocial outcomes of orthognathic treatment

Orthognathic treatment has been demonstrated to enhance oral function and quality of life. In the UK, prior approval criteria have been trialled to govern the provision of orthognathic surgery within the National Health Service (NHS). These include the patient's age and presence of functional concerns. The purpose of this paper was to examine the outcomes of orthognathic treatment with respect to patient age at the start of treatment. This was a retrospective evaluation of a single surgeon's experience of patients treated for dentofacial deformity over a 17-year period. A total of 118 patients completed pre-treatment and post-treatment questionnaires. There were significant improvements (p < 0.001) in reported functional problems, and in Body Satisfaction Scale (BSS), General Health Questionnaire (GHQ-12), and in Anxiety questionnaire scores. There was no difference in outcome when younger and older patients were compared. Orthognathic treatment produced positive functional and psychosocial outcomes irrespective of the patient's age at the start of treatment.

Body mass index and weight loss in patients submitted to orthognathic surgery: a prospective study

OBJECTIVE

To compare the body mass index (BMI) and the weight loss (WL) in patients with dentofacial deformities who underwent monomaxillary versus bimaxillary orthognathic surgery.

MATERIALS AND METHODS

This prospective longitudinal study included 69 patients with dentofacial deformities who underwent surgical orthodontic treatment. Patients were divided into two groups according to the type of orthognathic surgery: monomaxillary or bimaxillary. A preoperative nutritional assessment based on BMI was performed; the percentage of involuntary WL between the preoperative and postoperative periods was also calculated. Data were collected at preoperative and 10, 40, and 90 days postoperative (PO). Statistical analysis was performed using SPSS 17.0 (IBM Corp., Armonk, NY, USA), and data are reported with 95% confidence interval.

RESULTS

According to BMI, patients who underwent monomaxillary surgery presented: underweight = 2.6%, normal weight = 51.3%, overweight = 35.9%, and obese = 10.3%. The subjects who underwent bimaxillary surgery presented: normal weight = 43.3%, overweight = 36.7%, and obese = 20%. BMI was similar between the groups at all time points (preoperative, p= 0.237; 10 days PO, p= 0.325; 40 days PO, p= 0.430; and 90 days PO, p= 0.609). All patients lost weight postoperatively, and WL was similar among the PO measurements (p= 0.163).

CONCLUSIONS

Although both monomaxillary and bimaxillary orthognathic surgeries resulted in WL and lower BMI, there was no statistically significant difference in these metrics between the two types of surgery.

Maxillomandibular Advancement Efficacy in Obstructive Sleep Apnea Patients With Class 2 Versus 3 Dentofacial Deformity

OBJECTIVE

To compare the efficacy of maxillomandibular advancement (MMA) for patients with obstructive sleep apnea (OSA) with class 2 versus 3 dentofacial deformities (DFDs).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary sleep surgery center.

METHODS

Patients with OSA and DFD class 2 versus 3 undergoing MMA at Stanford Sleep Surgery between 2014 and 2021 were matched by preoperative body mass index (BMI), age, and sex. Postoperative outcome was compared with polysomnography measures and patient-reported outcome measures (PROMs).

RESULTS

Twenty-eight matched subjects, 14 in each deformity group were identified and assessed. The mean age (standard deviation) was 34.29 (10.21) and 33.86 (10.23) for classes 2 and 3, respectively. The apnea-hypopnea index (AHI) decreased from 43.42 (28.30) to 9.6 (5.29) (p < .001) and 37.17 (35.77) to 11.81 (15.74) (p = .042) in class 2 and 3 subjects, respectively. The oxygen desaturation index (ODI) changed from 30.48 (24.02) to 6.88 (3.39) (p = .024) and 11.43 (11.40) to 5.44 (7.96) (p = .85) in class 2 and 3 subjects, respectively. The Epworth sleepiness scale changed from 8.93 (5.28) to 3.91 (2.70) (p = .018) and 10.23 (4.38) to 4.22 (3.07) (p = .006) in class 2 and 3 subjects, respectively.

CONCLUSION

Among age, sex, and BMI-matched subjects, MMA is equally effective in both dentofacial class 2 and 3 groups, both objectively and subjectively. Preoperatively, dentofacial class 2 patients with OSA presented with the more severe disease with higher AHI and ODI. Dentofacial class 3 patients with OSA may require additional attention to improve nasal function outcomes.

Treatment of dentofacial deformities secondary to condylar hyperplasia

Dentofacial deformities secondary to condylar hyperplasiais a kind of disease presenting facial asymmetry, malocclusion, temporomandibular joint dysfunction, and other symptoms caused by non-neoplastic hyperplasia of the condyle. The etiology is still unknown, and currently, pre- and post-operative orthodontics accompanied by orthognathic surgery, temporomandibular joint surgery and jawbone contouring surgery are the main treatment methods. A personalized treatment plan was developed, considering the active degree of condyle hyperplasia, the severity of the jaw deformity, and the patient's will, to correct deformity, obtain ideal occlusal relationship, and regain good temporomandibular joint function. Combined with the author's clinical experience, the etiology, clinical and imageological features, treatment aims, and surgical methods of condylar hyperplasia and secondary dentofacial deformities were discussed in this paper.

Impact of orthognathic surgery on quality of life in patients with different dentofacial deformities: longitudinal study of the Oral Health Impact Profile (OHIP-14) with at least 1 year of follow-up

OBJECTIVE

The objective of this study was to assess the impact of orthognathic surgery for dental facial deformities on oral health-related quality of life (OHRQoL) in the immediate postoperative period up to at least 1 year after surgery.

STUDY DESIGN

This prospective study evaluated data from 85 patients. OHRQoL was assessed using the Dutch version of the Oral Health Impact Profile questionnaire (OHIP-14NL) preoperatively (T0), each day for 7 days postoperatively (T1-T7) and 4 weeks (T8), 6 months (T9), and at least 1 year (T10) after surgery. The total OHIP score was calculated for each patient, with higher OHIP scores indicating a worse impact on oral health. Patients also completed an extra questionnaire about self-care, discomfort, and experienced pain (rated on a 10-point scale) in the postoperative period (T1-T10).

RESULTS

The mean OHIP score increased sharply at T1 compared to T0 but decreased significantly in the first postoperative week. The mean OHIP score at T8 was still higher than before surgery. However, at T9 and T10, the mean OHIP score was significantly lower than at T0 (P < .05). No significant difference in OHIP score was found between gender, age, type of surgery, and indication for surgery. Pain significantly decreased from T6 to T0. The OHIP and pain scores significantly positively correlated at every time point except T9.

CONCLUSION

The findings indicate that OHRQoL is reduced from baseline in the immediate postoperative period but improves over time. By 1 year, OHRQoL improves significantly after orthognathic surgery in patients with dentofacial deformities.

[Surgery first as an alternative approach in patients treated for dentofacial deformities]

Recently surgery first became more popular alternative for treatment of dentofacial deformities. In this approach treatment starts from orthognathic surgery. Immediately after othognathic surgery facial aesthetics and oral function are improved. Thus main complaints of the orthognathic patients are resolved early during treatment period. Indications for surgery first approach are wider than years ago and include: skeletal Class II and III malocclusion, skeletal open bite, bimaxillary protrusion, even cases with severe facial asymmetry are reported. The key point for gaining stable results and total treatment time shortening is an appropriate surgical occlusion. For higher precision of treatment 3D virtual planning is recommended. Total treatment time depends on: number of contact points in surgical occlusion, number of extracted teeth and postsurgical midline deviation. Surgery first is a good alternative approach in some patients treated for dentofacial deformities. Stability in this approach is similar to conventional method of treatment and both methods result in quality of life improvement. As there is lack of presurgical orthodontics in surgery first approach patients avoid transient deterioration in facial aesthetics and oral function that results in higher satisfaction and shorter total treatment time.

Condyle modeling stability, craniofacial asymmetry and ACTN3 genotypes: Contribution to TMD prevalence in a cohort of dentofacial deformities

Craniofacial asymmetry, mandibular condylar modeling and temporomandibular joint disorders are common comorbidities of skeletally disproportionate malocclusions, but etiology of occurrence together is poorly understood. We compared asymmetry, condyle modeling stability and temporomandibular health in a cohort of 128 patients having orthodontics and orthognathic surgery to correct dentofacial deformity malocclusions. We also compared ACTN3 and ENPP1 genotypes for association to clinical conditions. Pre-surgical posterior-anterior cephalometric and panometric radiographic analyses; jaw pain and function questionnaire and clinical examination of TMD; and SNP-genotype analysis from saliva samples were compared to assess interrelationships. Almost half had asymmetries in need of surgical correction, which could be subdivided into four distinct morphological patterns. Asymmetric condyle modeling between sides was significantly greater in craniofacial asymmetry, but most commonly had an unanticipated pattern. Often, longer or larger condyles occurred on the shorter mandibular ramus side. Subjects with longer ramus but dimensionally smaller condyles were more likely to have self-reported TMD symptoms (p = 0.023) and significantly greater clinical diagnosis of TMD (p = 0 .000001), with masticatory myalgia most prominent. Genotyping found two significant genotype associations for ACTN3 rs1671064 (Q523R missense) p = 0.02; rs678397 (intronic SNP) p = 0.04 and one significant allele association rs1815739 (R577X nonsense) p = 0.00. Skeletal asymmetry, unusual condyle modeling and TMD are common and interrelated components of many dentofacial deformities. Imbalanced musculoskeletal functional adaptations and genetic or epigenetic influences contribute to the etiology, and require further investigation.

Complications associated with orthognathic surgery: A retrospective study of 485 cases

PURPOSE

To identify the most prevalent types of complications associated with orthognathic surgery and its possible risk factors.

METHODS

This study was a retrospective investigation of records of 485 patients who underwent orthognathic surgery between 2008 and 2014 at the Oral and Maxillofacial Surgery Service at the Federal University of Paraná, Curitiba, Brazil. Types of complications were recorded. Independent variables such as sex, age, duration of surgery and hospitalization, number of surgeries, surgical site, and types of osteotomy performed were evaluated. Complications were also evaluated based on the treatment according to the Clavien-Dindo Classification. Data were submitted to statistical analysis with a significance level of 0.05.

RESULTS

A total of 93 complications were reported (19.2%), including postoperative malocclusion, hemorrhage, inferior alveolar nerve injury, bad split, and infection. Complications were more common in men (p = 0.029). The number of complications was higher in surgeries that took more time to perform (p < 0.05) when the entire sample was taken into consideration. The prevalence of complications was related to a higher number of procedures per surgery (p = 0.019). Complications were more frequent in mandibular procedures (p = 0.010), particularly in bilateral sagittal split osteotomies (p < 0.001). Related to treatment, Clavien-Dindo grade I complications were the most frequent (72.04%). There was no association between sex, age, surgery duration, length of hospitalization, or surgical site with complication grades according to the Clavien-Dindo classification (p ≥ 0.05).

CONCLUSION

Postoperative malocclusion, hemorrhage, inferior alveolar nerve injury, bad split and infection are the most prevalent complication in orthognathic surgery. They seem to be related to sex, duration of surgery, number of surgeries, surgical site, and the type of osteotomy performed. With these in mind, it is possible to explain to the patient the different levels of severity of complications related to the surgery.

Interceptive Dentofacial Orthopedics (Growth Modification)

Although all dentofacial deformities involve deviation of skeletal and dental units that require correction, the timing and method of treatment can vary considerably. Growth is a key consideration when managing dentofacial deformities, because it has a direct impact on the timing and method of management. Some deformities may be intercepted and managed during growth, whereas others can only be definitively managed after cessation of growth. This article focuses on clinical considerations of growth in managing dentofacial deformities, and discusses methods of growth evaluation and interceptive orthodontic management strategies in different types of dentofacial deformities.

Orthognathic Surgery Treatment Need in a Turkish Adult Population: A Retrospective Study

Objectives: Limited information exists on orthognathic procedures and respective dentofacial deformities in Turkey. This retrospective study assessed the orthognathic surgery procedures in two universities, using the Index of Orthognathic Functional Treatment Need (IOFTN), and compared the IOFTN grades according to gender as well as sagittal and vertical skeletal relationships. Material and Methods: Records of 200 consecutive patients (120 females, 80 males, mean age = 23.4 (SD: 5.4) years) who received orthognathic treatment (2014–2018) were analyzed. Sagittal (ANB angle) and vertical skeletal type (GoGnSN angle), osteotomies, and IOFTN scores were recorded. Results: Class III, II, and I malocclusions formed 69%, 17.5%, and 13.5% of the samples, respectively. Class III skeletal relationships (69%) and high-angle cases (64%) were the most prevalent (p < 0.05). IOFTN scores were unevenly distributed among genders (p < 0.05) and the prevalent scores were 5.3 (40.5%), 4.3 (15.5%), 5.4 (13%), and 5.2 (7.5%), with 94% scoring 4 or 5 (great and very great functional need). Bimaxillary osteotomies were the most prevalent (55%), followed by LeFort I (32%), and 26% had genioplasty. Conclusion: IOFTN is a reliable tool to identify patients in need of orthognathic surgery. Class III malocclusions and Class III sagittal skeletal relationships were more common in this sample. Comparatively, a higher number of patients had genioplasty as a part of their treatment.

Facial asymmetry: virtual planning to optimize treatment predictability and aesthetic results

Facial asymmetry is a condition that compromises function and social interactions and, consequently, the quality of life. Orthodontic-surgical treatment may be indicated to achieve a stable occlusion and significant improvement in facial aesthetics. The virtual planning of the maxillary, mandibular and chin movements can be done prior to surgery. These movements can be successfully performed with the use of prototyped guides obtained from virtual planning. The aim of this article is to show the state of the art of treatments of facial asymmetries, and emphasize how important is the multi-disciplinary approach to achieve predictable aesthetic and functionally stable results in a patient with facial asymmetry and chin protrusion.

Postural assessment in class III patients before and after orthognathic surgery

PURPOSE

This study aimed to assess body posture before and after bimaxillary orthognathic surgery by photogrammetry in skeletal class III patients.

METHODS

Thirty-one patients with skeletal class III dentofacial deformities (14 men, 17 women) who underwent orthodontic preparation for surgery were included in this non-randomized controlled trial. Of these, 15 who did not undergo orthognathic surgery during the period of this study served as controls. Postural assessment was performed by photogrammetry using SAPO® (Postural Assessment Software) based on anterior-, posterior-, and lateral-view images taken 1 month before and 4 months after bimaxillary orthognathic surgery with internal rigid fixation (or 4 months after the initial assessment, for the control group). The study was approved by PUCRS Research Ethics Committee, and written informed consent was obtained from all individual participants prior to their inclusion in the study.

RESULTS

There was no significant difference between groups for age, gender, and GAP. In the intervention group, the right leg/hindfoot angle, which initially indicated a valgus deformity, normalized after intervention (P < 0.048). Posterior displacement of the head (P < 0.005) and trunk (P < 0.004) were observed after intervention.

CONCLUSIONS

These results suggest that correction of class III dentofacial deformities by bimaxillary orthognathic surgery can produce systemic postural adjustments, especially posterior displacement of the head and trunk and knee and ankle valgus.

Is Atypical Swallowing Associated With Relapse in Orthognathic Patients? A Retrospective Study of 256 Patients

PURPOSE

To determine the association of atypical swallowing (AS) with relapse in patients undergoing combined orthodontic and orthognathic treatment.

MATERIALS AND METHODS

In this retrospective cohort study, the clinical data of all patients who underwent combined surgical and orthodontic treatment from 1998 through 2015 at the University Hospital of Geneva (Geneva, Switzerland) were reviewed. The primary outcome variables were 1) AS and 2) post-treatment relapse. Other variables included, age, gender, dentofacial deformity (facial asymmetry, mandibular deficiency, mandibular excess, maxillary retrusion, open bite), surgical procedure performed (bilateral sagittal split osteotomy [BSSO] with or without Le Fort I osteotomy), and dental interocclusal relations according to Angle.

RESULTS

Of the 256 patients investigated, 23 (9%) showed relapse at 1 year after treatment. Multivariate analysis showed that AS status (before treatment, odds ratio [OR] = 9.44, P = .005; after treatment, OR = 56.17, P < .001; before and after treatment, OR = 20.49, P < .001) was significantly associated with relapse. The presence of a pretreatment open bite also was associated with an increased risk of relapse (OR = 0.04, P < .001) regardless of AS status.

CONCLUSION

The present study showed that in orthognathic patients 1) AS was associated with relapse regardless of dentofacial deformity or surgical procedure performed and 2) AS can appear after treatment in patients who were initially free of it.

A new approach of splint-less orthognathic surgery using a personalized orthognathic surgical guide system: A preliminary study

The purpose of this study was to evaluate a personalized orthognathic surgical guide (POSG) system for bimaxillary surgery without the use of surgical splint. Ten patients with dentofacial deformities were enrolled. Surgeries were planned with the computer-aided surgical simulation method. The POSG system was designed for both maxillary and mandibular surgery. Each consisted of cutting guides and three-dimensionally (3D) printed custom titanium plates to guide the osteotomy and repositioning the bony segments without the use of the surgical splints. Finally, the outcome evaluation was completed by comparing planned outcomes with postoperative outcomes. All operations were successfully completed using the POSG system. The largest root-mean-square deviations were 0.74mm and 1.93° for the maxillary dental arch, 1.10mm and 2.82° for the mandibular arch, 0.83mm and 2.59° for the mandibular body, and 0.98mm and 2.45° for the proximal segments. The results of the study indicated that our POSG system is capable of accurately and effectively transferring the surgical plan without the use of surgical splint. A significant advantage is that the repositioning of the bony segments is independent to the mandibular autorotation, thus eliminates the potential problems associated with the surgical splint.

An Overview of the Surgical Correction of Dentofacial Deformity

The correction of severe dentofacial discrepancies involving a combination of orthodontic and surgical therapies (termed ‘orthognathic treatment’) is commonplace. There is an abundance of evidence within this field but it is often inconsistent. This article is an evidence-based overview of such treatments and is aimed at the general dental practitioner. It will cover: the timing of treatment; the indications and risks associated with different surgical osteotomies; the magnitude of surgical movements that can be achieved with these procedures; and the importance of mandibular autorotation when planning treatment. Orthognathic treatment is considered to be the gold standard for comprehensive correction of severe dentofacial discrepancies. It is undertaken by a multidisciplinary team of clinicians involving, but not exclusive to, consultants in orthodontics and oral and maxillofacial surgery in secondary and tertiary medical centres throughout the United Kingdom. Clinical relevance: It is imperative that general dental practitioners have a good understanding of orthognathic treatment in order to recognize when such treatments are indicated, to inform the patient of possible treatment modalities and to be able to discuss associated risks in order to make appropriate referrals. Since treatment timing and magnitude of surgical movements have a profound effect on stability of the treatment result, these must be carefully considered by all clinicians involved in patient care to minimize relapse potential.

[Short sagittal osteotomy]

Bilateral sagittal split osteotomy has become the standard mandibular surgery for the treatment of dento-facial deformities. Even patients with less important deformities may undergo surgery. The morbidity must be as low as possible. We describe a technique with reduced split surfaces. The osseous section follows an oblique line since the thorn of Spix below and outside towards the supra-angular region. This section is completed by an osteotomy of the posterior border of the mandible. This split never reaches the inferior alveolar nerf tunnel. The protection of the alveolar nerve is increased what decreases considerably the risk of nervous complications of this intervention. The majority of the mandibular movements are possible by this technique with the exception of the important advancements and the increase of the height of the ramus.

Combined surgical-orthodontic treatment: how did it evolve and what are the best practices now?

It has been 50 years since the landmark presentation by Hugo Obwegeser at Walter Reed Army Hospital. At that conference, Professor Obwegeser offered American surgeons techniques to correct facial skeletal deformities with access through intraoral incisions. As important advances in surgical technique and anesthesia evolved for the surgical procedures, a major contribution by American orthodontists in collaboration with surgeons was the creation of a common diagnostic, planning, and treatment scheme for use by both clinician groups in the treatment of dentofacial deformities, the skeletal and dental problems of the most severely affected 5% of the population. This article summarizes what American orthodontists and surgeons have learned in the late 20th and early 21st centuries, and forecasts what might be the future of treatment for patients with dentofacial deformities.

[Skeletal discrepancies: could we avoid surgical procedures?]

Orthodontic-surgical protocols are nowadays considered as the state-of-the-art in cases of skeletal dentomaxillary dysmorphosis. However, for some reasons, it may happen that unquestionable indications for orthodontic-surgical procedures are not respected, patients being treated by orthodontics alone. This kind of mistake in the treatment planning lay the patient open to various potential complications such as: abnormal duration of the orthodontic treatment, dental root resorptions, questionable tooth extraction, unfavorable facial aesthetics, treatment instability... The authors discuss these points illustrated by clinical cases. Although orthognathic surgery protocols became considerably simplified these last two decades, orthodontic-surgical protocols are still relevantly considered as heavy both by patients and practitioners. As a consequence, their indication must be carefully weighed by a multidisciplinary team, keeping in mind that these protocols represent the ultimate functional and aesthetic treatment for dento-skeletal dysmorphoses.

[Analysis of a change in the position of the hyoid bone when displacing the lower jaw in patients with dentofacial malformations]

OBJECTIVE

To estimate the magnitude of a change in the position of the hyoid bone when displacing the lower jaw during surgical treatment in patients with dentofacial abnormalities.

MATERIAL AND METHODS

Fifty patients with dentofacial abnormalities (25 and 25 patients with distal and mesial occlusion, respectively) were examined and treated. All the patients underwent multislice spiral computed tomography before and 6 months after surgery. The authors developed linear quantities to analyze the position of the hyoid bone with respect to the skull base and cervical spine. The paired Wilcoxon signed-rank test was used.

RESULTS

None of the examined groups was noted to have a statistically significant change in the distance between the basihyoid and the vertebral column, suggesting that the datum was moderately changed. No case of worse respiratory function was found.

CONCLUSION

Our investigation has revealed that mandible displacement during orthognathic surgery causes no critcal change in the position of the hyoid bone and hence it has no significant impact on upper airway patency in this area.

Risk factors of neurosensory disturbance following orthognathic surgery

Objectives

To report the incidence of objective and subjective neurosensory disturbance (NSD) after orthognathic surgery in a major orthognathic centre in Hong Kong, and to investigate the risk factors that contributed to the incidence of NSD after orthognathic surgery.

Materials and Methods

A retrospective cross-sectional study on NSD after orthognathic surgery in a local major orthognathic centre. Patients who had bimaxillary orthognathic surgery reviewed at post-operative 6 months, 12 months or 24 months were recruited to undergo neurosensory tests with subjective and 3 objective assessments. Possible risk factors of NSD including subjects’ age and gender, surgical procedures and surgeons’ experience were analyzed.

Results

238 patients with 476 sides were recruited. The incidences of subjective NSD after maxillary procedures were 16.2%, 13% and 9.8% at post-operative 6 months, 12 months and 24 months, respectively; the incidences of subjective NSD after mandibular procedures were 35.4%, 36.6% and 34.6% at post-operative 6 months, 12 months and 24 months, respectively. Increased age was found to be a significant risk factor of NSD after orthognathic surgery at short term (at 6 months and 12 months) but not at 24 months. SSO has a significantly higher risk of NSD when compared to VSSO. SSO in combination with anterior mandibular surgery has a higher risk of NSD when compared to VSSO in combination with anterior mandibular surgery or anterior mandibular surgery alone. Gender of patients and surgeons’ experience were not found to be risk factors of NSD after orthognathic surgery.

Conclusion

The incidence of NSD after maxillary and mandibular orthognathic procedures at post-operative 6 months, 12 months and 24 months was reported. Increased age was identified as a risk factor of short term post-operative NSD but not in long term (24 months or more). Specific mandibular procedures were related to higher incidence of NSD after orthognathic surgery.

Health-related quality of life and depression in patients with dentofacial deformity

INTRODUCTION

Patients with dentofacial deformities present difficulties at work and in social adaptation. At the same time, they often appear depressed, and as a consequence, the psychosocial aspects of surgery play an important role. The aim of this study was to investigate the effects that depression causes in the quality of life of patients with dentofacial deformity.

MATERIAL AND METHODS

Filthy patients were recruited 1 year before undergoing orthognathic surgery and correlated oral and general health with the presence and absence of depression. In order to accomplish this, these patients received an adapted questionnaires of quality of life and Beck Depression Inventory to fill out. Fisher's test was applied, with a significance level of 5 %. Intercooled Stata version 9.0 was used to analyze data.

RESULTS

Among the eight domains of quality of life, there were three associated with depression status: vitality (p < 0.001), social aspects (p = 0.011), and mental health (p = 0.008).

DISCUSSION

There is growing interest in the impact of dentofacial deformity conditions on patients' quality of life. The scientific literature has discussed the social aspects of these deformities and showed that untreated patients had low self-esteem and suffered social restrictions before making the orthodontic and surgical treatments. This study concluded that the depression interferes significantly in vitality, social aspects of the individual, and mental health and, at the same time, emphasizes that the orthognathic surgery aims to not only restore esthetics and function to the patient but also improve the quality of life.

Masticatory function and temporomandibular disorders in patients with dentofacial deformities

About 30% of individuals in the Swedish population will at some stage during life have treatment with orthodontic appliances. In more severe cases, when orthodontic treatment is not considered sufficient enough to correct the malocclusion, the orthodontic treatment is combined with orthognathic surgery. For these cases, a satisfying jaw relation is achieved by surgically moving the maxilla and/or the mandible into a pre-planned position. Patients due to be treated with orthognathic surgery often suffer from an impaired masticatory function, symptoms from the masticatory muscles or temporomandibular joints (temporomandibular disorders), headaches as well as dissatisfaction with their facial aesthetics. Since orthognathic treatment is expensive, in many cases arduous to the patient and not without complications, it is important to assess the treatment outcome and if this is satisfying for the patients. Previous studies that have examined the outcome after orthognathic treatment have had diverging study designs and have come to different conclusions with regard to both temporomandibular disorders and masticatory function. The overall aim of this thesis was to assess and compare the frequencies of temporomandibular disorders and the masticatory function in patients with dentofacial deformities before and after orthognathic treatment. THE THESIS IS BASED ON THE FOLLOWING STUDIES: Paper I is a systematic literature review aiming to, in an evidence-based approach, answer the question whether orthognathic treatment affects the prevalence of signs and symptoms of temporomandibular disorders. The review encompasses the period from January 1966 to April 2006 and was further extended to May 2013 in the frame story of this thesis. CONCLUSIONS IN PAPER I AND THE COMPLEMENTARY SURVEY: There is insufficient scientific evidence for a decrease of sub diagnoses of temporomandibular disorders after orthognathic treatment. There is limited scientific evidence for a reduction of masticatory muscle pain on palpation after orthognathic treatment. There is insufficient scientific evidence for an effect on temporomandibular joint pain on palpation and temporomandibular joint sounds from orthognathic surgery. Further controlled, well-designed studies assessing temporomandibular disorders before and after orthognathic treatment are needed to consolidate strong evidence considering treatment outcomes. Papers II and III are studies comparing frequencies of temporomandibular disorders in patients with dentofacial deformities with a control group. The patients were referred for a combined orthodontic and orthognathic treatment to correct their malocclusion. The control group comprised individuals with normal occlusion or minor malocclusion traits not in need of orthodontic treatment. In Paper III, temporomandibular disorders were longitudinally analysed by assessing and comparing frequencies before and after orthognathic treatment. All individuals in the studies were diagnosed according to the research diagnostic criteria for temporomandibular disorders. CONCLUSIONS IN PAPERS II AND III: Patients due to be treated with orthognathic surgery had more signs and symptoms of temporomandibular disorders and a higher frequency of diagnosed temporomandibular disorders compared with the age- and gender matched control group. Patients with dentofacial deformities, corrected by orthodontic treatment in conjunction with orthognathic surgery, had a positive treatment outcome in respect of myofascial pain and arthralgia. After treatment the frequency of temporomandibular disorders . in the treatment group was low and at an equivalent level of that in the control group. Paper IV evaluates the self-estimated masticatory ability and the masticatory performance before and after orthognathic treatment in the same individuals as in Paper II and III. CONCLUSIONS IN PAPER IV: Masticatory ability and performance increased after orthognathic treatment. The number of occlusal contacts and severity of overall symptoms of TMD influenced both the masticatory ability and performance. Open bite had a negative effect on masticatory performance.