Double-jaw Surgery Research Articles

Quasi-least squares regression method with dentistry data.

In dentistry, single-jaw surgery or double-jaw surgery is performed depending on the patient's need to correct severe skeletal malocclusions. The effect of these surgical methods used in treatment is to be investigated with quasi-least squares regression (QLS), which is a new data analysis method for correlated data obtained by extending generalized estimating equations (GEE). The aim of this study is to investigate whether jaw surgery methods (single jaw and double jaw) and time are effective on some outcome variables (C point menton distance, cervical plane angle, distance from point C to pogonion perpendicular, angle between cervical plane and facial plane) using QLS method. In application, 114 measurements were performed on the lateral cephalometric radiographs of 34 patients aged 18 years and older who received orthodontic treatment and underwent surgery in the period of 2000-2018. The effects of time and group variables on four dependent variables were investigated and evaluated using QLS and GEE methods. Single-jaw surgery and double-jaw surgery as a group variable on all outcome variables were not significant. Among the working correlation structures used in QLS, the highest correlation value was obtained by "Markov" working correlation structure. Single-jaw surgery and double-jaw surgery were found to be statistically insignificant for outcome variables examined. QLS is superior to GEE in cases where repeated measurements are performed at unequal time intervals and there are missing observations.

Benefits of the enhanced recovery after surgery pathway for orthognathic surgery

The enhanced recovery after surgery (ERAS) protocol was designed to improve patient outcomes and decrease complications, opioid use, and postoperative nausea and vomiting (PONV). The aim of this retrospective cohort study was to examine the effectiveness of ERAS protocols implemented in orthognathic surgeries from 2017 to 2018 at the University of Alabama at Birmingham Hospital by measuring opioid use and PONV. Two groups were identified through chart review, a non-ERAS group (traditional) of patients who had surgery without a protocol and an ERAS group of patients who had surgery with the ERAS protocol. The anesthesia and surgical teams followed a standardized protocol for perioperative management. All procedures were performed by a single surgeon and included single- and double-jaw surgeries and adjunctive procedures. The patient charts were analyzed for postoperative opioid consumption (measured in morphine milligram equivalents, MME) and PONV. IBM SPSS Statistics version 26 was used to conduct the statistical analyses. The ERAS group received less opioids during the postoperative period than the control group (31.2 MME vs 54.6 MME, P= 0.002). The ERAS group also had a lower incidence of PONV, with 1.2 episodes of PONV compared to 2.4 episodes in the non-ERAS group (P= 0.008). This study demonstrates that the ERAS protocol is effective in decreasing postoperative opioid consumption and PONV.

Impact of orthognathic surgery on quality of life and comparison of patients’ postoperative experience after single- and double-jaw surgery: a longitudinal study

To evaluate the impact of orthognathic surgery on quality of life (QoL) and to compare single- and double-jaw surgeries in terms of ratio and patient perceptions of the postoperative period. A prospective, longitudinal observational study was conducted. The short form Oral Health Impact Profile (OHIP-14) and the Orthognathic Quality of Life Questionnaire (OQLQ) were applied preoperatively and 6 months postoperatively to evaluate oral health-related QoL (OHRQoL). Additionally, patient perceptions of the immediate postoperative period were assessed at the first and fourth week after surgery. One hundred consecutive patients were recruited and assigned to the single-jaw group (n=24) or the double-jaw group (n=76) according to the characteristics of each facial or occlusal deformity. The questionnaires showed lower scores for both groups after surgery, indicating significant benefits to OHRQoL. The whole sample OHIP-14 mean total scores decreased from 10.5 to 2.8 (P < .001, d=1.35), whereas OQLQ showed a decrease from 48.4 to 11.6 (P < .001, d=1.75). Orthognathic surgery can improve OHRQoL, and long-term benefits outweigh the risks and discomfort associated with the treatment.

Control of the occlusal plane in orthognathic surgery

• Diagnostic considerations of occlusal plane can make a treatment plan for better results. • Presurgical control of occlusal plane can contribute in reducing the need for double-jaw surgery. • Functional occlusal plane should be controlled to improve stability with better esthetics. • Adequate planning of occlusal plane orientation is of high significance in orthognathic surgery. The orientation of the occlusal plane (OP) influences the functional and esthetic balance of the face. We report on two patients for which the careful consideration of OP angulation from diagnosis to treatment planning aided in achieving a superior esthetic correction and improved stability. In both surgical patients, adequate presurgical control of the OP facilitated the surgical correction with a rotation of the OP. The results showed a better esthetic outcome and improved orientation of the musculoskeletal relation. Therefore, in severe mandibular prognathism or retrognathism, adequate planning of the OP orientation is of high significance.

Color changes of maxillary and mandibular incisors following surgical orthodontic treatment : Aprospective controlled clinical pilot study.

To assess possible color changes of natural teeth after surgical orthodontic treatment. This prospective controlled clinical pilot trial included 6consecutively treated surgical orthodontic patients with classIII malocclusion and neutral vertical relation (ST: surgical treatment), 3of which received double jaw osteotomies (SGI: surgical subgroupI) and 3received single mandibular sagittal split ramus osteotomies (SGII: surgical subgroupII). Eleven untreated individuals (UC: untreated control) and 9individuals who received conventional comprehensive orthodontic treatment only (OC: orthodontic control) served as controls. Tooth color measurements were performed using areflectance spectrophotometer on the upper and lower incisors before the initiation of the surgical orthodontic treatment (T1) and after its completion (T2). Primary endpoint was ∆E* (T1-T2) of summarized CIE-L*a*b* color differences. The null hypothesis of this study was that there is no statistically significant change in total tooth color difference ∆E* CIE-(L*a*b*) in vivo at baseline and following surgical orthodontic treatment. There was a statistically significant increase in ∆E* (T1-T2) in the ST group compared to the UC and OC groups. Single mandibular surgery had astronger effect on the lower teeth in comparison to double jaw surgery, while Le FortI osteotomy, as part SGI, had astronger effect on the upper teeth. Despite statistical significance, the majority of mean values of these color changes were lower than the threshold value of color alterations considered to be perceivable by the naked eye in aclinical setting (3.7 ∆E units), with the exception of the mandibular incisors in SGII, where this threshold value was slightly exceeded. Orthognathic surgery showed ameasurable effect on tooth color. However, esthetic disturbance or patient discomfort based on these color and lightness alterations are unlikely, due to their small impact and low perceptibility in aclinical setting.

The effects of orthognathic surgery on auditory function

BackgroundOrthognathic surgery is widely used in treating functional and skeletal problems. Any surgical procedure could cause side effects.ObjectivesThis study aimed to evaluate the potential changes in orthognathic surgery on the hearing function of patients.Materials and methodsThirty-one orthognathic surgery candidates were recruited in this study. Patients underwent either single or double jaw surgery. Pure tone audiometry (PTA), tympanometry, and Eustachian Tube Dysfunction Test (ETFT) were performed postoperatively at 24 h, 6 weeks, and 6 months after surgery. Patients were tabulated based on the type of maxilla and mandibular surgical movements (vertical and horizontal).ResultsPTA evaluation, based on horizontal or vertical movements, did not show significant differences, although vertical movements resulted in less change in hearing threshold. In other words, no significant changes occurred in patients’ hearing threshold after surgery. No significant difference was also observed between horizontal and vertical movements in the results of tympanometry. Negative changes were found in the results of ETFT in vertical movements, which returned to pre-surgery values in the final test.ConclusionsThe risk of minor changes in hearing function is probable during the first week after orthognathic surgery, but these negative changes will either totally fade or remain negligible. Patients gave informed consent preoperatively, and reassurance postoperatively is prudent.

Predictors of Opioid Prescription After Orthognathic Surgery in Opioid Naive Adults From a Large Database.

Orthognathic surgery often requires postoperative opioid pain management. The goal of this study was to examine opioid prescribing patterns in adults after orthognathic surgery and to analyze factors associated with high-dose postoperative opioid administration and persistent opioid use. We included opioid naive adults in the IBM MarketScan Databases who had undergone orthognathic surgery from 2003 to 2017. Three outcomes were examined: presence of a perioperative outpatient opioid claim; total oral morphine milliequivalents (MMEs) in the perioperative period; and persistent opioid use. Univariate analysis and multiple regression were used to determine associations between the outcomes and independent variables. Our study yielded a cohort of 8163 opioid naive adults, 45.6% of whom had an opioid claim in the perioperative period. The average prescribed MMEs in the perioperative period was 466 MMEs total, and 66 MMEs daily. Of patients with an opioid claim, 17.9% had persistent opioid use past 90 days. The presence of a complication was a predictor of having an opioid claim (P<0.001). Increasing age (P<0.001) and days hospitalized (P < 0.001) were associated with increased opioid usage. Persistent opioid use was associated with being prescribed more than 600 MMEs in the perioperative period (P < 0.001), as well as increasing age and days hospitalized. Interestingly, patients undergoing double-jaw surgery did not have significantly more opioids prescribed than those undergoing single-jaw surgery. Prescription opioids are relatively uncommon after jaw surgery, although 17.9% of patients continue to use opioids beyond 3 months after surgery. Predictors of persistent opioid use in this population include the number of days hospitalized, increasing age, and increasing amount of opioid prescribed postoperatively.

Incidence of condylar resorption after bimaxillary, Lefort I, and mandibular surgery: an overview

The aim of the present overview was to evaluate the outcomes of systematic reviews to determine the incidence of condylar resorption in patients submitted to orthognathic surgery and analyze whether the risk of developing this condition is related to a specific type of surgery. Searches were conducted in the PubMed/MEDLINE, Embase, and Cochrane electronic databases for systematic reviews with quantitative data on condylar resorption due to any type of orthognathic surgery for dentoskeletal deformities published up to May 25, 2019. The AMSTAR 2 and Glenny tools were applied for the quality appraisal. Five systematic reviews were included for analysis. Only one article was considered to have high quality. Among a total of 5128 patients, 12.32% developed condylar resorption. From those patients, 70.1% had double jaw surgery, 23.4% had mandibular surgery alone, and in 6.5% a Lefort I technique was used. Based on these findings, bimaxillary surgery could be considered a risk factor for condylar resorption. However, these results should be interpreted with caution, since other factors, such as pre-operative skeletal deformities, type of movement, and type of fixation, can contribute to the development of this condition. Further studies should consider reporting main cephalometric data, temporomandibular diagnosis, hormonal levels, and tomographic measures before and after the surgery at least every 6 months during the firsts two years to identify accurately risk factors for condylar resorption.

Association between Lateral Cephalometric Changes in X-Y Coordinate System and Profile Changes among Skeletal Class III Patients after Orthognathic Surgery.

BACKGROUNDSince aesthetic issues are the most important causes of referring skeletal class III patients to surgeons, investigating the impact of orthognathic surgeries on improving patient profiles increases the quality of treatment and quality of life. METHODSIn a retrospective observational-analytical study, 25 patients older than 18 years with class III skeletal malocclusion who had gone under both orthodontic and double-jaw orthognathic treatment were enrolled. Cephalometric imaging interval was before and at least 6 months after surgery. By defining a number of points and coordinate axes (X-Y), a criterion for comparing hard and soft tissue changes was obtained. These measurements were coordinated, linear and angular. The quantitative data were compared with data obtained using the Likert Scale Questionnaire by means of electronic “Google Forms” that was completed by orthodontists (n=5) and maxillofacial surgeons (n=5) to rank improvement in post-surgical profiles for both cephalometry and photography from poor to pleasant. Spearman Correlation Analysis was conducted between the quantitative and qualitative data.RESULTSVertical changes of point B and horizontal changes of point PNS showed correlation with improvement of patient profile. Changes in N-Pog line (R=-0.4), mandibular plane angle (R=-0.4) and nasolabial angle (NLA) (R=0.38) were significantly correlated with improvement of profiles. CONCLUSIONIn orthognathic double-jaw surgery on patients with skeletal Class III, forward movement of maxilla, upward positioning of mandible (decreasing anterior facial height), decreasing mandibular plane angle and increasing nasolabial angle would result in a better profile.

The relationship between fixation method and early central condylar sagging after bilateral sagittal split ramus osteotomy in orthognathic surgery

PurposeThere is no consensus about the ideal fixation methods and their effects on the condyle after the sagittal split ramus osteotomy (SSRO) procedure. The aim of this study was to compare the incidence, clinical presentation, and treatment of condylar sagging between different fixation methods following SSRO. MethodsPatients who underwent double jaw surgery between 2007 and 2017 were evaluated retrospectively. Mandibular fixation was maintained using one of three different options: a miniplate and a single bicortical screw, three bicortical screws, or a single bicortical screw. Some patients had malocclusion relapse in the early postoperative period due to condylar sagging, and needed reoperation. The reoperated condylar sagging patients were analysed statistically with respect to their fixation methods. Results233 patients (134 females, 99 males) with a mean age of 23.3 years were enrolled in the study. The patients fixated with a single bicortical screw had lower revision surgery rates than those with three bicortical screws or with miniplate with a single bicortical screw (p = 0.034 and p = 0.032, respectively). These differences in central condylar sagging with a need for revision were statistically significant. ConclusionAlthough a miniplate and a single bicortical screw and three bicortical screws are widely used after SSRO, if the priority is to avoid sagging then it seems that a single screw should be preferred for osteosynthesis.

Clockwise Rotation of the Occlusal Plane for Aesthetic Purposes by Double Jaw Surgery without Orthodontic Treatment.

The occlusal plane angle is an important factor in lateral facial aesthetics. Low occlusal plane facial profiles appear planar and long-faced, whereas high occlusal plane facial profiles are considered more attractive, especially in Asian regions. Clockwise rotation of the occlusal plane for truly aesthetic purposes can be accomplished with double jaw surgery, without need for orthodontic treatments. Patients with normal occlusion who desired to improve their lateral facial aesthetics were included in this study. A conventional Le Fort I osteotomy was followed by a sagittal split ramus osteotomy under general anesthesia. The movement of the maxillomandibular complex was determined in accord with a preoperative analysis. From 2015 to 2017, 43 patients with normal occlusion underwent double jaw surgery without orthodontic treatment. Whereas all patients were subjectively satisfied with the surgery, two underwent orthodontic treatment to correct mild occlusal discrepancies noticed after surgery. There were no delayed occlusal problems or relapses reported during the study. For patients who desired to improve their lateral facial aesthetics but had normal occlusion, orthognathic surgery without orthodontic treatment can be effective. Clockwise rotation of the occlusal plane by double jaw surgery without orthodontic treatment resulted in satisfactory aesthetic outcomes with stable and reliable long-term results. CLINICAL QUESTION/LEVEL OF EVIDENCE:: Therapeutic, IV.

Discussion: Clockwise Rotation of the Occlusal Plane for Aesthetic Purposes by Double Jaw Surgery without Orthodontic Treatment.

Summary:The occlusal plane angle is an important factor in lateral facial aesthetics. Low occlusal plane facial profiles appear planar and long-faced, whereas high occlusal plane facial profiles are considered more attractive, especially in Asian regions. Clockwise rotation of the occlusal plane for

Nasolabial Changes Following Double Jaw Surgery.

This study aimed to analyze 3-dimensional nasolabial soft tissue changes following double jaw surgery with Le Fort I maxillary advancement and relate them to underlying surgical movements. Pre- and post-surgical cone-beam computed tomography images of 37 maxillomandibular surgery patients with ≥2 mm of advancement at A-point were analyzed. Lateral cephalograms were constructed to determine horizontal and vertical surgical movements and 3-dimensional facial images were created from the CBCTs to calculate linear and angular changes. Alar base width increased 1.9 mm, nasal tip protrusion decreased 0.74 mm, the upper lip flattened 7.71 degree and increased 0.9 mm in length, nasal tip was displaced 2.47 mm superiorly causing an increased concavity of 5.52 degree for the overall dorsal surface and 3.99 degree at the supratip break angle (SBA), nasal tip angle decreased 2.16 degree and nasolabial angle decreased 7.37 degree. Correlations were found between underlying surgical movements and nasal tip protrusion, SBA, nasolabial angle (NLA), and nasal tip elevation (NTE). Multiple linear regression equations were calculated to predict changes in SBA from horizontal change at A-point, NLA from horizontal change at B-point, and NTE from the change at A-point horizontally and U1-tip vertically. Double jaw surgery with maxillary advancement has significant effects on nasolabial anatomy.

Three-Dimensional Morphological Changes of the Upper Airway in Patients With Skeletal Class III Malocclusion After Orthognathic Surgery.

To evaluate the morphological changes of the upper airway of patients with skeletal Class III malocclusion after undergoing bilateral mandibular ramus dislocated mandibular retrogression (SSRO) or SSRO combined with Le Fort I maxillary osteotomy and 3-dimensional imaging. All previous studies related to the upper airway in patients with skeletal class III malocclusion and orthognathic surgery were collected from the PubMed, EMB, Cochrane Library, Web of science, ClinicalKey, EBSCO, Weipu, Wanfang, China National Knowledge Infrastructure, and Chinese BioMedical Literature databases. The search date ends in August 2017. RevMan5.3 software was used to perform a meta-analysis related to upper airway morphology. Ten studies were included. The meta-analysis showed that 6 months after SSRO, CV1, and CV2 did not change significantly (P >0.05), whereas CV3 and CV4 narrowed (P <0.05) and remained narrow after 1 year (P <0.05). (CV1,CV2,CV3,CV4: Plans parallel to the FH plane passing through the most anterior inferior point of the anterior arch of the atlas, the 2nd cervical vertebra, the 3rd cervical vertebra, the 4th cervical vertebra.) There was no significant change in nasopharyngeal volume or laryngeal pharyngeal volume (P >0.05), but oropharyngeal volume and total volume decreased (P ≤0.01). Six months after SSRO combined with Le Fort I maxillary osteotomy, the minimum cross-sectional area of the upper airway was smaller (P <0.05), there was no significant change in nasopharyngeal volume or oropharyngeal volume (P >0.05), and oropharynx volume and total volume decreased (P <0.05). Single and double jaw surgery has no significant effect on nasopharynx and oropharynx, but reduces laryngopharynx and total volume; however, whether this will result in postoperative obstructive sleep apnea-hypopnea syndrome or become ameliorated over time requires more in-depth study and a longer period of clinical observation.

PSYCHOLOGICAL, SOCIAL AND ECONOMIC, SATISFACTION OF DOUBLE JAW SURGERY VS. SINGLE JAW SURGERY: A RETROSPECTIVE CLINICAL STUDY.

16Sep 2019 PSYCHOLOGICAL, SOCIAL AND ECONOMIC, SATISFACTION OF DOUBLE JAW SURGERY VS. SINGLE JAW SURGERY: A RETROSPECTIVE CLINICAL STUDY. Maryam Al-Hindi , Mohammed Alkindi , Noura AlOtaibi , Safa Alrashed and Syed Sirajul Hassan. Assistant Professor and Consultant Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, King Saud University. Associate Professor and Chairman of Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, King Saud University. Lecturer, Faculty of Dentistry, King Saud University. Private Sector King Saud University. Assistant Consultant Oral & Maxillofacial Surgery (Surgical Dentistry) King Saud University.

The Effect of Bimaxillary Surgery on the Airway Morphology in Class III Patients: Taking Into Account the Head Posture During Walking.

To assess changes in head and neck posture, airway, hyoid, tongue, and soft palate in skeletal class III individuals whose cephalograms were taken using dynamic natural head positioning method with an inclinometer. This study was conducted on 20 class III patients operated with double jaw surgery. Natural head positions were determined before and 6 months after the surgery. Craniocervical, pharyngeal airway, tongue, and hyoid positions were measured. In the analysis of the data, paired t test, independent sample t test and correlation tests were used. There was a statistically significant change in the craniocervical measurements with the operation and the head position was further extended (P < 0.05). Significant changes were observed in the soft palate angles upon surgery (P < 0.026) and the increase in oropharyngeal airway area was statistically significant (P < 0.001). There was a statistically significant increase in tongue length (TL) and distance from vertical reference plane to tongue tip (TTi/VRP) measurements (P < 0.001 and P < 0.012, respectively). There was a statistically significant decrease in distance from horizontal reference plane to tongue tip (TTi/HRP) and tongue dorsum (TD/HRP) measurements (P < 0.033 and P < 0.003, respectively). The only significant change among the hyoid bone position-related measurements was distance between hyoidale and epiglottis (P < 0.013). Hyoid bone location, tongue measurements, and posterior pharyngeal airway were found to be related to each other and they have been found to be effective on the head and neck posture. Head position will be affected by possible surgical alternatives.

Interaction Analysis of Risk Factors for Long-Term Skeletal Relapse Following Mandibular Advancement with Bilateral Sagittal Split Osteotomy

The aim of this study was to identify interaction effects among risk factors for long-term skeletal relapse. The study sample consisted of 96 patients who underwent mandibular advancement with bilateral sagittal split osteotomy. Ten predictor variables were analyzed for an interaction effect: sex, age, preoperative temporomandibular joint symptoms, mandibular plane angle (MPA), single or double jaw surgery, clockwise or counterclockwise mandibular rotation, magnitude of mandibular advancement, concomitant genioplasty, type of fixation, and follow-up duration. Modeling interactions between pairs of covariates were applied to detect a significant interaction among these risk factors on horizontal and vertical long-term skeletal relapse, respectively. Stratification analyses and two-way full factorial interaction analyses were performed to demonstrate how the interaction influenced the associations between covariates and relapse. The interactions between sex and mandibular rotation (P=0.006) and between MPA and mandibular rotation (P=0.002) were statistically significant for horizontal long-term skeletal relapse. No significant interaction was identified for vertical relapse. This study showed that female patients and those with an MPA ≥30° undergoing counterclockwise mandibular rotation are predisposed to greater horizontal long-term skeletal relapse. Therefore, the judicious use of counterclockwise rotation is recommended in order to minimize the relapse, especially in female patients and those with a high MPA.

Interaction analysis of risk factors for long-term skeletal relapse following mandibular advancement with bilateral sagittal split osteotomy

The aim of this study was to identify interaction effects among risk factors for long-term skeletal relapse. The study sample consisted of 96 patients who underwent mandibular advancement with bilateral sagittal split osteotomy. Ten predictor variables were analyzed for an interaction effect: sex, age, preoperative temporomandibular joint symptoms, mandibular plane angle (MPA), single or double jaw surgery, clockwise or counterclockwise mandibular rotation, magnitude of mandibular advancement, concomitant genioplasty, type of fixation, and follow-up duration. Modeling interactions between pairs of covariates were applied to detect a significant interaction among these risk factors on horizontal and vertical long-term skeletal relapse, respectively. Stratification analyses and two-way full factorial interaction analyses were performed to demonstrate how the interaction influenced the associations between covariates and relapse. The interactions between sex and mandibular rotation (P=0.006) and between MPA and mandibular rotation (P=0.002) were statistically significant for horizontal long-term skeletal relapse. No significant interaction was identified for vertical relapse. This study showed that female patients and those with an MPA ≥30° undergoing counterclockwise mandibular rotation are predisposed to greater horizontal long-term skeletal relapse. Therefore, the judicious use of counterclockwise rotation is recommended in order to minimize the relapse, especially in female patients and those with a high MPA.

Characterization of facial asymmetry in skeletal Class III malocclusion and its implications for treatment

Jaw deviation is frequently seen in Class III patients. The aim of the study was to investigate asymmetric features of skeletal, dental and soft tissues in three types of jaw asymmetry based on our previously reported classification system. The cone-beam computed tomography (CBCT) images of 70 Class III patients were analysed. Group 1 patients showed large shift of menton and synchronous but smaller ramus deviation. The maxillomandibular complex had roll and yaw rotations to the menton-deviation side. Maxillary and dental asymmetry was obvious in transverse and vertical dimensions. Cant of occlusal plane and lip line was apparent. Group 2 patients also exhibited menton and ramus deviation to the same side but the discrepancy in ramus width was larger than menton shift. Asymmetry in Group 2 resulted from a bodily side shift of the maxillomandibular complex without obvious rotation. Group 3 patients had menton and ramus deviated in opposite directions which seemed secondary to a yaw rotation. Double-jaw surgery is generally required for Groups 1 and 3 while Group 2 patients may be successfully treated by mandibular surgery only provided that arch width discrepancy can be managed by orthodontic measures.

Accuracy of three-dimensional planning in maxillary repositioning in double-jaw orthognathic surgery: how far along are we? a retrospective analysis of 100 patients

Accuracy of three-dimensional planning in maxillary repositioning in double-jaw orthognathic surgery: how far along are we? a retrospective analysis of 100 patients