Recommendations to minimize tooth root remodeling in patients undergoing maxillary osteotomies.

The purpose of this study was to report root remodeling/resorption percentages of maxillary teeth following the different maxillary osteotomies; i.e. one-piece, two-pieces, three-pieces Le Fort I, surgically assisted rapid palatal expansion (SARPE). The possibility of relationships between root remodeling and various patient- and/or treatment-related factors were further investigated. A total of 110 patients (1075 teeth) who underwent combined orthodontic and orthognathic surgery were studied retrospectively. The sample size was divided into: 30 patients in one-piece Le Fort I group, 30 patients in multi-pieces Le Fort I group, 20 patients in SARPE group and 30 patients in orthodontic group. Preoperative and 1 year postoperative cone beam computed tomography (CBCT) scans were obtained. A validated and automated method for evaluating root remodeling and resorption in three dimensions (3D) was applied. SARPE group showed the highest percentage of root remodeling. Spearman correlation coefficient revealed a positive relationship between maxillary advancement and root remodeling, with more advancement contributing to more root remodeling. On the other hand, the orthodontic group showed a negative correlation with age indicating increased root remodeling in younger patients. Based on the reported results of linear, volumetric and morphological changes of the root after 1 year, clinical recommendations were provided in the form of decision tree flowchart and tables. These recommendations can serve as a valuable resource for surgeons in estimating and managing root remodeling and resorption associated with different maxillary surgical techniques.

Determination of safety margin of nasal septum osteotomy for sphenoid sinus in cleft lip and palate patients.

BACKGROUND: Nasal septum osteotomy is used for separating the nasal septum and maxilla during a Le Fort I osteotomy. If this osteotomy is applied too high or is tilted into the nasal cavity, the sphenoid sinus and various adjacent vital structures may be damaged, and serious bleeding, neurological complications, blindness or even death may occur. The aim of this study is to determine the safety margin of the nasal septum osteotomy for sphenoid sinus during the Le Fort I surgery in cleft lip and palate (CLP) patients. METHODS: Twenty cleft lip and palate (the CLP group) and 20 healthy individuals (the control group) were included in this study. Three values (two lines and an angle) were measured by cone beam computed tomography (CBCT). The first line is the line passing through the junction of the spina nasalis anterior point and the lower point of the perpendicular lamina of the palatine bone. The undersired line is the line passing through the junction of the spina nasalis anterior point and the lower anterior border of the base of the sphenoid sinus. The osteotomy angle is the angle between these two lines. RESULTS: In the control group; a surgical line of 44.11-61.14 mm (mean 51.91 ± 4.32), an undesired line of 52.48-69.58 mm (mean 59.14 ± 5.08) and an angle of 18.22-27.270 (mean 22.66 ± 2.55) were found, while in the CLP group, a surgical line of 34.53-51.16 mm (mean 43.38 ± 4.79), an undesired line of 46.86-61.35 mm (mean 55.02 ± 3.24) and an angle of 17.60-28.810 (mean 22.60 ± 2.81) were found. CONCLUSIONS: Although the angle to the sphenoid sinus was not significantly affected by CLP, careful planning and consideration of these anatomical differences are crucial to prevent complications and ensure the safety of Le Fort I surgery in CLP patients. Further research with larger sample sizes and subgroup analysis of unilateral and bilateral CLP cases is needed to improve our understanding of these anatomical variations and improve surgical approaches to individuals with CLP undergoing orthognathic procedures.

Nasal profile changes after LeFort I osteotomy (maxillary advancement) with and without ANS reduction in class III skeletal patients: a study protocol for a randomized clinical trial.

BACKGROUND: Dentofacial malformation is a common condition that affects a significant portion of the population, resulting in functional and aesthetic defects. Orthognathic surgeries, such as LeFort I osteotomy, are performed to correct these abnormalities. However, the impact of these surgeries on nasal profile changes remains unclear. Additionally, the role of anterior nasal spine (ANS) reduction in maxillary advancement surgeries of 3-5 mm range is yet to be determined. This study aims to investigate the effect of ANS reduction on soft tissue profile changes following LeFort I osteotomy with a maxillary advancement range of 3-5 mm in class III skeletal patients. The hypothesis is that the changes in nasolabial angle and upper lip length will not significantly differ between patients who undergo LeFort I osteotomy with and without ANS reduction. METHOD AND DESIGN: This study is designed as a randomized controlled trial. A total of 26 class III skeletal patients with maxillofacial abnormalities will be recruited from the maxillofacial clinic of Bu-Ali and Farahikhtegan Hospitals in Tehran, Iran. Patients meeting the inclusion criteria will be randomly assigned to two groups: one group will undergo LeFort I osteotomy with ANS reduction, and the other group will undergo LeFort I osteotomy without ANS reduction. The soft tissue profile changes, specifically the nasolabial angle and upper lip length, will be evaluated and compared between the two groups. DISCUSSION: Achieving facial harmony through orthognathic surgery requires careful planning and consideration of the impact on surrounding soft tissue. The primary objective is to predict and plan for the effects on the nasolabial region. LeFort I osteotomy is a common procedure used to correct dentofacial deformities, particularly in class III patients. Maxillary advancement during this surgery can lead to changes in nasal tip position, width, and rotation, potentially due to repositioning of the anterior nasal spine and soft tissue dissection. In this study, soft tissue changes will be assessed in non-growing class III patients using cephalometric radiographs. The impact of reducing the anterior nasal spine (ANS) on nasal profile changes will be investigated for maxillary advancements of 3-5 mm. Objective measurements and patient-reported outcomes will be evaluated to gain insights into the aesthetic outcomes of orthognathic surgery. The findings will provide valuable guidance for treatment decisions and alternative options based on expected nasal profile changes. TRIAL REGISTRATION: This project was registered at The Iranian Registry of Clinical Trials (Identifier No. IRCT20210928052625N1, Website: https://www.irct.ir/trial/59171 ) and Open Science Framework (OSF) (Registration https://doi.org/10.17605/OSF.IO/X3HD4 ). 2021-06-09.

Stability between single and segmental maxillary osteotomies in bimaxillary surgery for cleft-associated class III deformity: a CBCT study.

OBJECTIVE: Segmental Le Fort I osteotomy through the cleft is a common strategy to narrow the alveolar cleft in adults. This study compared skeletal stability between single and segmental Le Fort I osteotomies in patients with unilateral cleft lip and palate (UCLP). MATERIALS AND METHODS: This retrospective analysis examined 45 adults with complete UCLP-associated class III deformities who underwent bimaxillary surgery with either single (n = 30) or segmental (n = 15) Le Fort I advancement. Cone beam computed tomography (CBCT) scans of the facial skeleton were acquired before surgery, 1-week postsurgery, and at follow-up. Measures of landmarks from the CBCT images for the two treatment groups were compared for translation (left/right, posterior/anterior, superior/inferior) and rotation (yaw, roll, pitch). RESULTS: Postsurgery, the downward movement of the maxilla was larger in the segmental group than the single group. At follow-up, the maxilla moved backward in both groups, and upward in the segmental group. The mandible moved forward and upward and rotated upward in both groups. The amount of upward movement and rotation was larger in the segmental group than the single group. CONCLUSIONS: Two years after bimaxillary surgery in patients with UCLP-associated class III deformity, greater relapse was found after segmental Le Fort I osteotomies in vertical translation of the maxilla and mandible, and pitch rotation of the mandible compared with single Le Fort I osteotomies. CLINICAL RELEVANCE: The vertical relapse of the maxilla was larger after segmental Le Fort I advancement compared with single Le Fort I advancement in clefts.

Monitoring of Home Respiratory Polygraphy During Mandibular Distraction Osteogenesis Succeeded by LeFort I Osteotomy in Adult Patients With Obstructive Sleep Apnea.

BACKGROUND: Bilateral internal ramus distraction (BIRD) is now part of select protocols for treating obstructive sleep apnea (OSA). Introducing a home monitoring protocol offers a valuable alternative to overnight laboratory polysomnography (PSG). PURPOSE: The purpose of this study was to evaluate and compare OSA parameters obtained via home respiratory polygraphy (HRP) and hospital PSG in a cohort of patients undergoing mandibular distraction for OSA management. STUDY DESIGN, SETTING, SAMPLE: Hospital Universitario La Princesa (Madrid) researchers conducted a prospective cohort study with patients diagnosed with moderate (apnea-hypopnea index (AHI) = 15 to 30) to severe (AHI>30) OSA undergoing BIRD followed by LeFort maxillary osteotomy. Exclusion criteria were as follows: severe systemic diseases, central apneas, smoking, poor dental hygiene, or prior OSA interventions. PREDICTOR VARIABLE: The predictor variable was PSG and HRP techniques. MAIN OUTCOME VARIABLES: The main outcome variable comprises a collection of OSA parameters, including the AHI, oxygen desaturation index (ODI), and time spent below 90% oxygen saturation (T90). These data were measured both before and after distraction, as well as after 6 mm, 9 mm, and 12 mm of mandibular distraction. COVARIATES: The covariates were age, sex, cardiovascular risk parameters, and the Epworth sleepiness scale. ANALYSES: Pearson's correlation analyzed AHI, ODI, and T90 values from PSG and HRP. Wilcoxon Signed Rank-Sum Test compared 2 distraction stages, and the Friedman Test evaluated 3 stages (P < .05). Multiple regression analysis assessed if covariates were independent risk factors for postoperative persistent OSA. RESULTS: The study included 32 patients (25% with moderate and 75% with severe OSA). Final AHI was 10.9 ± 8.9 (events/hour) with HRP, compared to 15.2 ± 13.4 with PSG (r = 0.7, P < .05). ODI was 9.0 ± 8.1 (des/h) with HRP and 8.7 ± 9.5 with PSG (r = 0.85, P < .05). T90 was 1.6 ± 2.2 with HRP and 1.3 ± 3.0 with PSG (r = 0.6, P < .05). Based on HRP data, AHI improved from D1 (34.0 ± 19.5) to D2 (20.8 ± 14.1) and D3 (12.5 ± 10.4) (P < .05). ODI decreased from D1 (26.1 ± 19.0) to D2 (16.0 ± 12.6) and D3 (9.4 ± 8.8) (P < .05). T90 reduced from D1 (8.2 ± 12.6) to D2 (4.1 ± 5.2) and D3 (1.9 ± 2.8) (P < .05). Multiple regression analysis of comorbidities produced nonsignificant results. CONCLUSION AND RELEVANCE: Monitoring BIRD through HRP has demonstrated efficacy in yielding results that align with PSG.

On the feasibility of minimally invasive Le Fort I with patient-specific implants: Proof of concept.

A novel approach to Le Fort I osteotomy is presented, integrating patient-specific implants (PSIs), osteosynthesis and cutting guides within a minimally invasive surgical framework, and the accuracy of the procedure is assessed through 3D voxel-based superimposition. The technique was applied in 5 cases. Differences between the surgical plan and final outcome were evaluated as follows: a 2-mm color scale was established to assess the anterior surfaces of the maxilla, mandible and chin, as well as the condylar surfaces. Measurements were made at 8 specific landmarks, and all of them showed a mean difference of less than 1 mm. In conclusion, the described protocol allows for minimally invasive Le Fort I osteotomy using PSIs. Besides, although the accuracy of the results may be limited by the small sample size, the findings are consistent with those reported in the literature. A prospective comparative study is needed to obtain statistically significant results and draw meaningful conclusions.

Mandibular Body Osteotomy Combined with Sagittal Split Ramus Osteotomy for the Treatment of Severe Skeletal Class â ¢ Malocclusion with Ankylosed Teeth.

This study presents a combination of 2 different surgery procedures performed on the mandible as part of the treatment aiming to improve the facial profile and occlusal function of patients with severe skeletal class Ⅲ malocclusion and bilateral edentulous gaps. The teeth next to the edentulous gaps were found to be ankylosed. Mandibular setback by bilateral sagittal split ramus osteotomies and mandibular body osteotomies, combined with Le Fort Ⅰ level maxillary advancement were performed, since the chief complaint of the patient was a concave profile. As a result, the skeletal class Ⅲ malocclusion had been corrected, a satisfying facial profile had been achieved, and no apparent adverse effect was found. Thus, it has been proved that the combination of sagittal split ramus osteotomy and mandibular body osteotomy is available for correcting skeletal class Ⅲ malocclusion.

Comprehensive analysis of lateral nasal wall anatomy to optimize the osteotomy in different skeletal patterns.

PURPOSE: Variations in nasal wall anatomy are crucial in patients with dentofacial deformities undergoing Le Fort I osteotomy. These structural variations heighten the potential for complications during surgical procedures. Hence, the study focused on evaluating the differences in the lateral nasal wall anatomy across different skeletal Classes. METHODS: This study evaluated 86 patients aged 18-43 years with different skeletal Classes. In the axial images acquired from coronal sections, two angulations and the linear distances of the lateral nasal wall were measured in Class I, II, and III patients. The measurement between the piriform opening and the most anterior point of the greater palatine foramen was evaluated in three parts regarding the osteotomy line. Differences between the skeletal patterns were analyzed using an independent sample t-test and Mann-Whitney U test with a significance level of 0.05. The intra-class correlation coefficient was calculated for inter-observer and intra-observer agreement. RESULTS: There was a statistically significant difference between Class I and Class II subjects regarding the anterior lateral nasal wall (p = 0.011) and anterior nasal thickness (a) (0.004). There was a significant difference between Class I and Class III patients regarding anterior nasal thickness (a) (p < 0.001) and total lateral nasal wall length (p < 0.001). CONCLUSION: For instance, the measurements of Class III and Class II patients were relatively different from those of the Class I patients. Therefore, preoperative Cone-Beam Computed Tomographic analysis should be performed for each patient prior to Le Fort I osteotomy to ensure that the procedure is performed safely.

Does Maxillomandibular Fixation Technique Affect Occlusion Quality in Segmental LeFort I Osteotomy?

BACKGROUND: Segmental maxillary osteotomies require precise occlusal control due to variability in individual segment positioning. The role of maxillomandibular fixation (MMF) technique on occlusal control has not been validated. PURPOSE: The purpose is to measure and compare the accuracy of occlusal positioning among MMF techniques. STUDY DESIGN, SETTING, SAMPLE: This was a double-blinded in vitro study on experiment models to simulate a 3-piece LeFort I osteotomy. The models were constricted posteriorly and expanded using 3 different MMF techniques and compared to the unaltered baseline occlusion. Based on sample size calculation, 32 separate attempts were made for each MMF technique. PREDICTOR VARIABLE: The predictor variable was MMF technique (brackets, MMF screws, and embrasure wires). MAIN OUTCOME VARIABLES: The primary outcome variable was the visual occlusal analysis score, a 1.00 to 4.00 continuous scale measuring the similarity of the achieved occlusion to the planned (control) occlusion assessed by an oral and maxillofacial surgeon and an orthodontist. High visual occlusal analysis score indicated greater occlusal accuracy, with 3.50 defined as the threshold for accuracy. The secondary outcome variable was the linear error of the achieved occlusion at the canine and first molar teeth, with lower error indicating greater accuracy. An a priori accuracy threshold of 0.5 mm was set for this variable. COVARIATES: None. ANALYSES: Kruskal-Wallis test with post hoc testing was used to analyze the difference in the outcome variables of interest. P value < .05 was considered statistically significant. RESULTS: Thirty-two attempts for each technique showed that brackets had higher VAOS than MMF screws and embrasure wires (median differences 1.49 and 0.48, P < .001), and had lower linear occlusal error (median differences 0.35 to 0.99 mm, P < .001). CONCLUSION AND RELEVANCE: MMF technique influences the quality of occlusal control, with greater visual rating scores and lower linear errors seen with brackets than with embrasure wires or MMF screws.

Comparative Analysis of Temperature-Responsive Hydrogel (PF 72) for Postoperative Pain After Bimaxillary Surgery: A Retro-spective Study.

Bimaxillary surgery is a painful invasive procedure in plastic surgery. Pain control is typically achieved using intravenous analgesics. We aimed to investigate the efficacy of a novel temperature-responsive hydrogel, PF72, mixed with ropivacaine, as a local pain management solution when applied directly to the surgical site following orthognathic surgery. The study was conducted from October 2022 to July 2023 and included a cohort of 40 candidates for orthognathic surgery, encompassing LeFort I maxillary ostectomy and sagittal split ramus osteotomy. The participants were divided into an Injection group (n = 20), where PF72 was administered at the surgical site before the orthognathic surgery, and a Control group (n = 20), which relied solely on intravenous analgesics. Pain was evaluated at 3, 6, 24, 48, and 72 h after surgery using a numerical rating scale (NRS). The mean NRS scores at 24 h were 6.35 and 4 for the Control and Injection groups, respectively. The mean NRS scores at 72 h were 3.4 and 2.55 for the Control and Injection groups, respectively. Patients who received PF72 experienced less pain than those who received intravenous analgesics. These findings underscore the potential of PF72 as an effective alternative for enhancing pain management in patients undergoing orthognathic surgery.Level of Evidence III Therapeutic study. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Validation of a fully automatic three-dimensional assessment of orthognathic surgery.

The aim of the present study was to propose and validate FAST3D: a fully automatic three-dimensional (3D) assessment of the surgical accuracy and the long-term skeletal stability of orthognathic surgery. To validate FAST3D, the agreement between FAST3D and a validated state-of-the-art semi-automatic method was calculated by intra-class correlation coefficients (ICC) at a 95 % confidence interval. A one-sided hypothesis test was performed to evaluate whether the absolute discrepancy between the measurements produced by the two methods was statistically significantly below a clinically relevant error margin of 0.5 mm. Ten subjects (six male, four female; mean age 24.4 years), class II and III, who underwent a combined three-piece Le Fort I osteotomy, bilateral sagittal split osteotomy and genioplasty, were included in the validation study. The agreement between the two methods was excellent for all measurements, ICC range (0.85-1.00), and fair for the rotational stability of the chin, ICC = 0.54. The absolute discrepancy for all measurements was statistically significantly lower than the clinical relevant error margin (p < 0.008). Within the limitations of the present validation study, FAST3D demonstrated to be reliable and may be adopted whenever appropriate in order to reduce the work load of the medical staff.

Simultaneous standard total joint prosthesis reconstruction with SSRO and Le Fort I osteotomy in the treatment of unilateral temporomandibular joint ankylosis with jaw deformity: a case cohort study.

OBJECTIVE: Unilateral temporomandibular joint ankylosis with jaw deformity (UTMJAJD) may require simultaneous total joint prosthesis (TJP) reconstruction, sagittal split ramus (SSRO), and Le Fort I osteotomies. The purpose of this study was to evaluate outcomes in patients treated with these procedures. METHODS: Patients diagnosed UTMJAJD between 2016 and 2018 were selected for the study. Mandible-first procedure was performed after ankylosis release with TJP on the ankylosed side and SSRO on the contralateral side. Le Fort I osteotomy with and without genioplasty was lastly performed. Maximal incisor opening (MIO), facial symmetry, and jaw and condyle stability were compared before, after operation, and during follow-ups. RESULTS: Seven patients were included in the study. Their average chin deviation was 9.5 ± 4.2 mm, and maxillary cant was 5.1 ± 3.0°. After operation, jaw deformity significantly improved, with chin deviation corrected 7.6 ± 4.1 mm (p = 0.015) and advanced 5.9 ± 2.5 mm (p = 0.006). After an average follow-up of 26.6 ± 17.1 months, MIO significantly increased from 11.4 ± 9.3 to 35.7 ± 2.6 mm (p = 0.000). The occlusion was stable with no significant positional or rotational changes of the jaw (p > 0.05). There was no obvious condylar resorption during follow-ups. CONCLUSION: Simultaneous TJP reconstruction, SSRO, and Le Fort I osteotomy are reliable and effective methods for the treatment of UTMJAJD.

Mandibular autorotation: a critical virtual parameter in clinical decision-making regarding maxilla-first versus mandible-first sequence.

Large degrees of mandibular autorotation during intermediate splint design are prone to transfer error and decrease accuracy. The purpose of this study was to evaluate the amount of mandibular autorotation necessary to design intermediate splints for maxilla- and mandible-first sequences using virtual planning software, to help the clinical decision-making regarding the most adequate sequence for each patient. The influence of specific orthognathic movements (different vertical and sagittal changes at the Le Fort I level, cant correction) and the type of maxillofacial deformity (skeletal Class II, III, anterior open bite) were evaluated to identify those that would require higher levels of autorotation for each sequence. Three-dimensional virtual surgical planning data of 194 patients were reviewed (126 female, 68 male; mean age 26.5 ± 11.0 years; 143 skeletal Class II, 51 skeletal Class III) and subgroup analyses were conducted using the Kruskal-Wallis test and post-hoc pairwise comparisons. As an additional parameter (mandibular autorotation), maxilla-first is indicated for bimaxillary osteotomies with Le Fort I posterior intrusion, anterior open bite, and skeletal Class III, while mandible-first is recommended for Le Fort I global extrusion, especially with maxillary cant correction.

Skeletal stability after maxillary distraction osteogenesis or conventional Le Fort I osteotomy in patients with cleft lip and palate: A superimposition-based cephalometric analysis.

PURPOSE: The aim was to assess skeletal stability after maxillary advancement using either distraction osteogenesis (DO) or conventional Le Fort I osteotomy (CO) in patients with cleft lip and palate (CLP) or cleft palate (CP) utilising a new superimposition-based cephalometric method. METHOD: This retrospective study included patients who were treated with DO (N = 12) or CO (N = 9). Sagittal and vertical changes after surgery, and skeletal stability at 18 months post-operatively were assessed with superimposition-based cephalometry, comparing lateral cephalograms performed pre-operatively (T0), post-operatively after CO or immediately after completed distraction in DO (T1), and at 18 months of follow-up (T2). RESULTS: The mean sagittal movements from T0 to T2 in the DO and CO groups were 5.9 mm and 2.2 mm, respectively, with a skeletal relapse rate of 16% in the DO group and 15% in the CO group between T1 and T2. The vertical mean movement from T0 to T2 in the DO and CO groups was 2.8 mm and 2.0 mm, respectively, and the skeletal relapse rate between T1 and T2 was 36% in the DO group and 32% in the CO group. CONCLUSION: Sagittal advancement of the maxilla was stable, in contrast to the vertical downward movement, which showed more-extensive relapse in both groups. Despite more-extensive maxillary advancement in the DO group, the rates of skeletal relapse were similar.

[Comparison of the virtual surgical planning position of maxilla and condyle with the postoperative real position in patients with mandibular protrusion].

OBJECTIVE: To compare the difference between virtual surgical planning (VSP) position and postoperative real position of maxilla and condyle, and to explore the degree of intraoperative realization of VSP after orthognathic surgery. METHODS: In this study, 36 patients with mandibular protrusion deformity from January 2022 to December 2022 were included. All the patients had been done bilateral sagittal split ramus osteotomy (SSRO) combined with Le Fort Ⅰ osteotomy under guidance of VSP. The VSP data (T0) and 1-week postoperative CT (T1) were collected, the 3D model of postoperative CT was established and segmented into upper and lower jaws in CCMF Plan software. At the same time, accor-ding to the morphology of palatal folds, the virtual design was registered with the postoperative model, and the unclear maxillary dentition in the postoperative model was replaced. Then the postoperative model was matched with VSP model by registration of upper skull anatomy that was not affected by the operation. The three-dimensional reference plane and coordinate system were established. Selecting anatomical landmarks and their connections of condyle and maxilla for the measurement, we compared the coordinate changes of marker points in three directions, and the angle changes between the line connecting the marker points and the reference plane to analyze the positional deviation and the angle deviation of the postoperative condyle and maxilla compared to VSP. RESULTS: The postoperative real position of the maxilla deviates from the VSP by nearly 1 mm in the horizontal and vertical directions, and the anteroposterior deviation was about 1.5 mm. In addition, most patients had a certain degree of counterclockwise rotation of the maxilla after surgery. Most of the bilateral condyle moved forward, outward and downward (the average distance deviation was 0.15 mm, 1.54 mm, 2.19 mm, respectively), and rotated forward, outward and upward (the average degree deviation was 4.32°, 1.02°, 0.86°, respectively) compared with the VSP. CONCLUSION: VSP can be mostly achieved by assistance of 3D printed occlusal plates, but there are certain deviations in the postoperative real position of maxilla and condyle compared with VSP, which may be related to the rotation axis of the mandible in the VSP. It is necessary to use patient personalized condylar rotation axis for VSP, and apply condylar positioning device to further improve surgical accuracy.

Three-dimensional positioning of the maxilla using novel intermediate splints in maxilla-first orthognathic surgery for correction of skeletal class III deformity.

OBJECTIVES: Successful orthognathic surgery requires accurate transfer of the intraoperative surgical plan. This study aimed to (1) evaluate the surgical error of a novel intermediate splint in positioning the maxilla during maxilla-first orthognathic surgery and (2) determine factors influencing surgical error. MATERIALS AND METHODS: This prospective study examined 83 patients who consecutively underwent Le Fort I osteotomy for correction of skeletal class III deformity using a novel intermediate splint and a bilateral sagittal split osteotomy. Surgical error was the outcome variable, measured as the difference in postoperative translational and rotational maxillary position from the virtual plan. Measures included asymmetry, need and amount for mandibular opening during fabrication of intermediate splints, and planned and achieved skeletal movement. RESULTS: Mean errors in translation for vertical, sagittal, and transversal dimensions were 1.0 ± 0.7 mm, 1.0 ± 0.6 mm, and 0.7 ± 0.6 mm, respectively; degrees in rotation for yaw, roll, and pitch were 0.8 ± 0.6, 0.6 ± 0.4, and 1.6 ± 1.1, respectively. The transverse error was smaller than sagittal and vertical errors; error for pitch was larger than roll and yaw (both p < 0.001). Error for sagittal, transverse, and roll positioning was affected by the achieved skeletal movement (roll, p < 0.05; pitch and yaw, p < 0.001). Surgical error of pitch positioning was affected by planned and achieved skeletal movement (both p < 0.001). CONCLUSIONS: Using the novel intermediate splint when performing Le Fort I osteotomy allowed for accurate positioning of the maxilla. CLINICAL RELEVANCE: The novel intermediate splint for maxillary positioning can be reliably used in clinical routines.

Le fort I osteotomy with or without concomitant removal of upper third molars: A prospective cohort study of intraoperative findings, related complications, and level of pterygomaxillary separation after down-fracture.

The main objective of our study was to assess the clinical implications of concomitant intraoperative removal of maxillary third molars (M3M) with the Le Fort I osteotomy 'twist' technique (LF1twist). A prospective comparative study was carried out regarding the necessity of bone trimming around the pedicle, intra- and postoperative complications, surgery time, and the level of pterygomaxillary junction (PMJ) separation following LF1twist with concomitant intraoperative removal of M3M (test group) versus LF1twist alone (control group). Outcome parameters were assessed from clinical and radiographic measurements. In total, 100 surgery sites were included (50 in each group). The mean surgery time was 53.4 ± 7.8 min, with nonsignificant differences between groups. The frequency of intraoperative complications was negligible, with no significant differences between groups - though all bleeding events (n = 4) occurred when M3M was not removed concomitantly. No postoperative complications were recorded. Percentages of disarticulations occurring at the PMJ were similar in both groups. In conclusion, the results demonstrate that removal of M3M in conjunction with LF1twist does not imply additional surgery time, or differences regarding the level of PMJ separation or perioperative complications. Furthermore, the concomitant procedure reduces the amount of maxillary and palatal bone in the disjunction area, which facilitates down-fracture and field clearing for maxillary repositioning.

Evaluation of transpalatal distraction in cleft palate patients.

PURPOSE: The aim of this study was to evaluate the effect of combining a bone-borne palatal expander (distractor) with a maxillary osteotomy in the treatment of narrowed maxillae in treated cleft palate patients. Few articles in the literature isolated the effects of transpalatal distraction in cleft patients and most either excluded cleft patients or grouped them with non-cleft patients. The hypothesis is that the use of a bone-borne palatal expander in conjunction with a maxillary osteotomy would improve the amount of maxillary expansion at the anterior segment with less tipping of the segments and provide a harmonious arch form. METHODS: We studied four patients above 14 years of age with repaired cleft palate and progressive anterior constriction of the arch. All patients received a bone-borne distractor (UNI-Smile Distractor, Titamed, Belgium) combined with a LeFort I level osteotomy without pterygomaxillary disjunction. Dental models and CBCT measurements were used to analyze the skeletal and dental effects of the intervention. RESULT: All the patients who completed the trial had satisfactory expansion and normalization of the maxillary arch form. The average increase in the intercanine distance was 12.9 mm while the average increase in the intermolar distance was 7.2 mm. No significant change in molar inclination or buccal bone thickness was observed. CONCLUSION: The use of bone-borne palatal expanders aided by a maxillary osteotomy (transpalatal distraction) in treated cleft palate patients can provide a harmonious arch form in adolescent and adult patients. This trial was registered in the clinical trials registry with the ID NCT03837652 on February 12, 2019.

Does Anesthesiologist Experience Influence Early Postoperative Outcomes Following Orthognathic Surgery?

BACKGROUND: Anesthesia provider experience impacts nausea and vomiting in other surgical specialties but its influence within orthognathic surgery remains unclear. PURPOSE: The study purpose was to evaluate whether anesthesiologist experience with orthognathic surgery impacts postoperative outcomes, including nausea, emesis, narcotic use, and perioperative adverse events, for patients undergoing orthognathic surgery. STUDY DESIGN, SETTING, SAMPLE: This is a retrospective cohort study of subjects aged 12 to 35 years old who underwent orthognathic surgery, including Le Fort 1 osteotomy ± bilateral sagittal split osteotomy, at Boston Children's Hospital from August 2018 to January 2022. Subjects were excluded if they had incomplete medical records, a syndromic diagnosis, or a hospital stay of greater than 2 days. PREDICTOR VARIABLE: The predictor variable was attending anesthesia provider experience with orthognathic surgery. Providers were classified as experienced or inexperienced, with experienced providers defined as having anesthetized ≥10 orthognathic operations during the study period. MAIN OUTCOME VARIABLES: The primary outcome variable was postoperative nausea. Secondary outcome variables were emesis, narcotic use in the hospital, and perioperative adverse events within 30 days of their operation. COVARIATES: Study covariates included age, sex, race, comorbidities (body mass index, history of psychiatric illness, cleft lip and/or palate, chronic pain, postoperative nausea/vomiting, gastrointestinal conditions), enhanced recovery after surgery protocol enrollment, and intraoperative factors (operation performed, anesthesia/procedure times, estimated blood loss, intravenous fluid and narcotic administration, and anesthesiologist's years in practice). ANALYSES: χ2 and unpaired t-tests were used to compare primary predictor and covariates against outcome variables. A P-value <.05 was considered significant. RESULTS: There were 118 subjects included in the study after 4 were excluded (51.7% female, mean age 19.1 ± 3.30 years). There were 71 operations performed by 5 experienced anesthesiologists (mean cases/provider 15.4 ± 5.95) and 47 cases by 22 different inexperienced providers (mean cases/provider 1.91 ± 1.16). The nausea rate was 52.1% for experienced providers and 53.2% for inexperienced providers (P = .909). There were no statistically significant associations between anesthesiologist experience and any outcome variable (P > .341). CONCLUSIONS AND RELEVANCE: Anesthesia providers' experience with orthognathic surgery did not significantly influence postoperative nausea, emesis, narcotic use, or perioperative adverse events.

Objective assessment of visual attention in orthognathic surgery training based on eye tracking.

The aim of this study was to investigate the differences in visual attention between novices and orthognathic experts, as well as to provide evidence for use in developing and optimizing training strategies for orthognathic surgery. Novice and orthognathic experts were recruited, and their distributions of visual attention were monitored via an eye-tracking device while they watched orthognathic surgery videos. The percentages of visual fixation duration devoted to the areas of interest - surgical objects, instruments controlled by the main surgeon, and instruments controlled by the assistants - in each orthognathic surgery section were analyzed and compared between the two groups using repeated-measures factorial analysis of variance (ANOVA). In total, there were 18 participants, comprising both novices (n = 9) and experts (n = 9). For all sections of orthognathic surgery, the percentage of fixation duration on surgical objects was significantly higher for the novices than for the experts (p = 0.031, p = 0.005, p = 0.026, p = 0.047, p = 0.047, p = 0.031, p = 0.027, p = 0.034, p = 0.008, and p = 0.016). During the maxillary segment separation as part of Le Fort I osteotomy and the splitting of the mandible as part of bilateral sagittal split osteotomy, the novices also had a higher percentage of fixation duration on the instruments controlled by the main surgeon, as compared with the experts (p = 0.007 and p = 0.048, respectively). Novices invested great cognitive effort into the surgical objects in each section of orthognathic surgery, including the instruments controlled by the main surgeon in the maxillary segment separation and the splitting of the mandible. Strengthening this aspect of instruction could help novices reduce their cognitive load and achieve mastery more efficiently.