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.

The correlation of maxillomandibular advancement and airway volume change in obstructive sleep apnea using cone beam computed tomography.

The purpose of this retrospective study was to evaluate the correlation of maxillomandibular advancement (MMA) and airway volume changes in patients with obstructive sleep apnea (OSA), and to determine the surgical skeletal movements necessary to achieve an increase in total airway volume (TAV) of ≥70%. Thirty patients with OSA treated by MMA were evaluated. Pre- and postoperative cone beam computed tomography images were used to determine the horizontal distance and angular changes in surgical parameters and linear, area, and volumetric airway parameters. Postoperatively, the horizontal distance of surgical parameters (A-point, UI, B-point, pogonion, and menton) and craniofacial angulation (SNA and SNB) increased significantly, similar to total surface area, TAV, and minimum cross-sectional area of the airway (p<0.0001). The total airway length decreased significantly (p<0.0001). The mean increase in TAV was 67.2%. There were positive correlations between linear surgical changes and the percentage change in TAV. All surgical parameters were predictive of a change in TAV ≥70%. The optimal surgical change was 6mm for A-point, 7.9mm for UI, 7.6mm for B-point, 11.2mm for pogonion, and 10mm for menton. In conclusion, maxillary advancement of less than 10mm was adequate in this study to obtain an increase in the TAV of at least 70%.

Differential enamel and osteogenic gene expression profiles in odontogenic tumors.

Odontogenic tumors occur within the jaw bones and may be derived from odontogenic epithelium or ectomesenchyme or contain active components of both tissue types. We investigated the gene expression profile of enamel matrix proteins (EMPs), genes related to osteogenesis, and the mineralization process in odontogenic tumor cell populations focusing on an ameloblastoma (AB-1), a keratocystic odontogenic tumor (KCOT-1), and a calcifying epithelial odontogenic tumor (CEOT-1). All cell populations were shown to be epithelial in origin by CK14 expression. All tested EMPs were expressed by all odontogenic tumor cell types, with higher transcript levels seen in the AB-1 population especially for AMEL, AMBN, and ODAM. CEOT-1 cell populations showed a greater content of ALP-positive cells as well as higher ALP mRNA levels. Using qRT-PCR, we found a higher expression of 8 genes in the CEOT-1 compared to the AB-1 and KCOT-1. In this study we demonstrated the establishment of AB-1, KCOT-1 and CEOT-1 cell populations. The unique gene expression profiles of AB-1, KCOT-1, and CEOT-1 cells and their interactions with the surrounding microenvironment may support their unique tumor development, progression, and survival.

Strength analysis of Le Fort I osteotomy fixation: titanium versus resorbable plates.

PURPOSE: The purpose of this study was to compare the biomechanical characteristics of metallic and polymeric fixation systems using a 3-dimensional skull model to simulate clinical conditions of maxillary advancement and loading. MATERIAL AND METHODS: Standard titanium, prebent titanium, and resorbable plates and mesh were applied to surgically altered polyurethane skulls. The constructs were loaded using an Instron machine (Instron Inc, Canton, MA) in anterior-posterior (AP) and inferior-superior (IS) directions. The load displacement, load to failure, and deformation magnitudes and modes of failure were recorded. Statistical studies included analysis of variance (ANOVA) at P <.05. RESULTS: Elastic stiffness was different among groups in the AP direction, but no significant difference was found in the IS direction. The IS loading direction load displacement (stiffness) was significantly greater than that on AP loading. The maximum load for permanent deformation was larger in the AP direction, while the maximum load for breaking was larger in the IS direction. CONCLUSION: The overall evaluation of the model and test analyses supported the relative value of this in vitro system and study procedure. All systems showed load capacity magnitudes above 285 N (64 lbs) and more elastic resistance in the IS direction. The resorbable systems showed lower elastic stiffness compared with the titanium systems, but they appear to be adequate for fixation and withstanding the forces of mastication.

Soft tissue changes of the upper lip associated with maxillary advancement in obstructive sleep apnea patients.

PURPOSE: This retrospective study evaluated the horizontal and vertical soft tissue changes that occur with maxillary advancement surgery with a Le Fort I osteotomy with concomitant anatomic reorientation of the nasolabial musculature. SUBJECTS AND METHODS: Fifteen OSA patients who underwent maxillary advancement with a Le Fort I osteotomy without adjunctive nasal soft tissue procedures were studied after a minimum of 8 months of follow-up. The V-Y technique was used to close the maxillary vestibular incision. Only cases with minimal vertical movement (< 3.5 mm) in which no orthodontics were used were included. The average maxillary advancement was 8.0 +/- 2.5 mm, measured at the upper incisor (UPI) and the average vertical movement was 0.7 +/- 1.8 mm. The horizontal and vertical soft tissue change in subnasale (SN), labrale superiorus (LS), superior stomion (SS), nasal tip (NT), nasolabial angle (NLA), and lip length were measured in each patient and correlated with hard tissue measurements at anterior nasal spine (ANS) and UPI. The effect of lip thickness on these soft tissue changes also was evaluated. RESULTS: Using mean data, the horizontal soft-to-hard-tissue ratio for LS to UPI was 0.80:1, with a concomitant vertical (superior) soft tissue change to hard tissue advancement of 0.16:1. Lip length did not change significantly. All patients except 1 showed a slight decrease in nasolabial angle. The average decrease was 5 (range, -10 to +7 ). There was no statistically significant correlation between the degree of change in NLA and the amount of maxillary advancement. CONCLUSION: This study showed that advancement of the maxilla when controlling vertical movement resulted in the a hard-to-soft-tissue ratio of LS:UPI of 0.80:1. NLA did not change significantly.

A case report. Chondromatosis of the temporomandibular joint.

Synovial chondromatosis is a rare pathological condition that usually affects large joints but can affect the temporomandibular joint. The disease typically manifests itself with signs and symptoms similar to internal derangement. The disease is characterized by free-floating or attached cartilaginous bodies in the joint space. In this article, the authors present a case of synovial chondromatosis and discuss its pathological process. They also discuss diagnostic approaches and current treatment.

Surgical management of impacted third molars.

Teeth may become impacted when they fail to erupt or develop into the proper functional location. As such, impacted teeth are considered nonfunctional, abnormal, and pathological. The mandibular third molar is the most common tooth to become impacted. The cause of impacted third molars is thought to be inadequate space. Several studies indicate that a change from a coarse, attritive diet to a modern, refined diet has lead to an increased incidence of impacted teeth. Interproximal attrition allows for greater mesial migration of teeth and space for third molar teeth. Teeth that fail to attain a functional position may be pathological and should be considered for removal. The indications for removing impacted teeth can be divided into those of acute or chronic pathology. Impacted third molars are often associated with pain, infection, cyst formation, benign tumors, root resorption, bone loss, periodontal disease, and caries. The decision to surgically remove impacted third molars is often unclear. There are no absolute treatment protocols established. The dentist must consider a variety of factors and make an informed decision with the patient. Most experienced clinicians combine objective data and common sense to arrive at a logical treatment plan. The purpose of this article is to discuss factors related to impacted teeth and help the orthodontist understand the general management of impacted third molars. The decision for surgery will be assisted by an understanding of all of the risk factors associated with impacted teeth and presenting the options to the patient.

Bone grafting for the alveolar cleft defect.

Seventy-five percent of all cleft lip and palate patients have osseous defects of the alveolus. Bone grafting of this defect normalizes facial and dental function. Failure to reconstruct the osseous deformity may result in oronasal fistula, fluid reflux, speech pathology, anteroposterior deficiency of the maxilla, transverse deficiency of the maxilla, lack of bone support for the incisors and cuspids, dental crowding, and facial asymmetry. Bone grafting unifies the maxilla and is best done after the majority of facial growth is complete and the secondary dentition is erupting. This is known as secondary bone grafting and yields the best results. The dentofacial deformity of cleft lip and palate is best managed by coordination of dental development, surgery and orthodontics.

The stability of maxillary advancement using Le Fort I osteotomy with and without genial bone grafting.

The purpose of this study was to determine whether better stability is achieved with genial bone grafts and four-plate rigid fixation for large advancement Le Fort I osteotomies of the maxilla than with nongrafted osteotomies. We analyzed radiographic data on 22 patients with obstructive sleep apnea syndrome. All patients underwent Le Fort I osteotomy for maxillary advancement, 11 patients without bone grafts and 11 patients with bone grafts harvested from the mandibular symphyseal area. Bilateral sagittal split advancement osteotomies and genial tubercle advancements were also performed in all patients. Patients in the genial bone-grafted group had a mean advancement (surgical change) of 9.7 mm and a mean relapse (postsurgical change) of 0.7 mm (7%). Patients who had rigid fixation alone had a mean advancement of 10 mm and a mean relapse of 1.8 mm (18%). It is concluded that the stability with genial bone grafts to the lateral wall of the maxilla with four-plate rigid fixation was better than in the nongrafted group.

Maxillomandibular advancement surgery in obstructive sleep apnea syndrome patients: long-term surgical stability.

PURPOSE: This study examined the long-term skeletal stability of relatively large maxillomandibular advancement surgery in the treatment of obstructive sleep apnea syndrome (OSAS). MATERIALS AND METHODS: The presurgical, immediate (< 1 month), and long-term (> 12 months) postsurgical cephalometric radiographs of 19 patients undergoing maxillomandibular advancement with simultaneous genioplasty for OSAS were studied. The cephalometric measurements and calculations were performed using a commercial cephalometric software. RESULTS: Maxillary and mandibular advancement seems to be stable in the horizontal and vertical planes over the long term. There was no significant correlation between the amount of surgical advancement and the amount of postsurgical instability, with the exception of gonion in the vertical plane. CONCLUSION: The results from this study indicate that large surgical advancements in OSAS patients result in relatively stable repositioning of the maxilla and mandible over the long term.

Autologous TMJ disk replacement.

Several techniques have been advocated for replacement of displaced or diseased temporomandibular joint disks. Techniques are reviewed and the author's experience in managing this complex problem is presented.

Long-term skeletal stability after rigid fixation of Le Fort I osteotomies with advancements.

The purpose of this retrospective study was to evaluate relapse, comparing large and small maxillary advancements with four-plate rigid fixation and without bone grafting. All patients had obstructive sleep apnea, and underwent bimaxillary surgery. Standardized cephalometric analysis by two separate examiners was performed on serial radiographs of 20 patients immediately before surgery, and at 1 week and at least 6 months postoperatively (mean 18.5 months). The group was divided into three subsets to determine whether the magnitude of maxillary advancement correlated with the magnitude of relapse. In group 1 (< or = 6 mm, n = 4), the average advancement was 4.7 +/- 0.8 mm, with a mean relapse of 0 +/- 0.6 mm. In group 2 (7-9 mm, n = 9), the average advancement was 8.2 mm +/- 0.9, with a mean relapse of 0.7 +/- 1.5 mm. In group 3 (> or = 10 mm, n = 7), the mean advancement was 12.3 +/- 2.8 mm, with a mean relapse of 1.9 +/- 1.8 mm. There was no statistical difference in the measured relapse among the groups.

In vitro strength analysis of sagittal split osteotomy fixation: noncompression monocortical plates versus bicortical position screws.

An in vitro study using bovine ribs was performed to compare the strength of monocortical plates with bicortical position screws. An osteotomy was created to simulate a sagittal split and a 5-mm bone gap was produced. Four study groups were created: screw nongap, screw with gap, plate nongap, and plate with gap. Parameters of strength were analyzed by elastic deformation, stiffness ratio, permanent deformation, and breaking load. The results showed that monocortical plate fixation in bovine ribs provides less rigidity and is more susceptible to deformation than is bicortical position screw fixation.