Outcomes of conventional versus virtual surgical planning of orthognathic surgery using surgery-first approach for class III asymmetry.

OBJECTIVES: To determine if patient outcome variables differ between conventional and virtual surgical planning of orthognathic surgery for class III asymmetry. MATERIAL AND METHODS: This retrospective case-control study examined 95 patients with class III asymmetry who had been consecutively treated with at least a Le Fort I osteotomy and a bilateral sagittal split osteotomy with a surgery-first approach. Two groups were examined: 51 patients treated with conventional surgical planning and 44 with virtual surgical planning. After treatment, quantitative assessment was determined with measurements of midline symmetry, contour symmetry, and overall facial symmetry using standardized frontal photographs. Subject assessments were analyzed with questionnaires regarding self-perception of overall appearance, satisfaction with appearance, and quality of life. RESULTS: Conventional and virtual surgical planning resulted in significant improvements in outcomes for all patients. However, facial midline and overall facial symmetry were significantly greater for the virtual compared with the conventional group. There were no significant differences in subjective measures of appearance, satisfaction with appearance, and quality of life for patients treated with conventional or virtual surgical planning; measures were high for both groups. CONCLUSIONS: Conventional and virtual surgical planning of surgery-first bimaxillary orthognathic surgery resulted in quantitative and qualitative improvements in facial symmetry. Although patient satisfaction was similar for both approaches, virtual surgical planning was superior to conventional surgical planning for the improvement of midline and overall asymmetry. CLINICAL RELEVANCE: Improvements with virtual surgical planning in facial midline, facial contour, and overall facial symmetry are as good as or better than conventional surgical planning.

The Medial Subcoronoid Process Region as a Novel Source of Bone Grafts in Orthognathic Surgery and Genioplasty.

BACKGROUND: Since 2012, the authors have adopted the medial subcoronoid process bone interpositional grafting in OGS and genioplasty procedures. The purpose of this study was to present the technical details and clinical outcomes of this alternative bone interpositional grafting for LeFort I and chin osteotomies. METHODS: Consecutive patients (n = 50) who underwent single-splint bimaxillary OGS with or without genioplasty and received medial subcoronoid bone interpositional grafting were included. Standardized facial and intraoral photographs at early and late postoperative periods (12.2 ±â€Š3.3 and 44.8 ±â€Š8.4 months postsurgery, respectively) were blindly rated to assess facial symmetry, chin, and occlusion status based on qualitative rating scales. Complication and reoperation rates were also reviewed. RESULTS: The medial subcoronoid bone interpositional grafts were adopted to stabilize different LeFort I maxillary movement types or lengthening/advancing genioplasty (36 and 14 patients, respectively). Overall, the early facial symmetry, chin, and occlusion status were maintained at late evolutions. None of the patients had donor-site or bone graft-related complications (i.e., bad split, undesired mandible fracture, infection, fibrous union, nonunion, and/or permanent neurosensory deficit) or revisionary surgery during follow-up. CONCLUSION: The medial subcoronoid process bone grafting was a feasible alternative for bone interpositional defects of LeFort I and chin osteotomies with no significant morbidity and avoiding secondary donor sites.

The radiographic and functional outcome of bilateral mandibular condylar head fractures: a comparison between open and closed treatment.

UNLABELLED: Bilateral mandibular condylar fractures accounts for 24% to 33% of condylar fractures but the indications of open reduction of bilateral condylar fracture are still controversial. It is generally accepted that displaced subcondylar fractures are indicated for open reduction, but the proper treatment of condylar head fractures are still variable. This retrospective study compares the radiographical and functional outcomes of bilateral condylar head fractures between open and closed reduction groups. MATERIALS AND METHODS: From February 1994 to June 2012, a total of 85 patients with bilateral condylar head fractures were retrospectively reviewed. Among this group, 41 cases underwent open reductions while the other 44 cases had closed reductions. Only adult patients with adequate follow-up and complete radiographic study were included in this study: consisting of 20 patients in the open group and 18 patients in the closed group.The subjective symptoms including temporomandibular joints (TMJ) symptoms, complications or adverse sequelae, and functional results, such as maximal mouth opening, were recorded. The outcome of patient's satisfaction was individually assessed by an independent reviewer. The computed tomographic results after treatment were evaluated between both groups. RESULTS: The mean follow-up period was 25.5±13.3 months. The open reduction group had better postoperative chewing functions, less malocclusion rates, less degree of TMJ pain (p=0.046), better radiographic outcome (p=0.036), and an overall satisfaction rate (p=0.039).There were 4 cases of failure in the closed reduction group. Subsequent open reduction (n=2) and redo closed reduction with intermaxillary fixation (n=2) were performed. Eleven patients in the close reduction group presented persistent malocclusion through objective evaluation. The subsequent treatment included further orthognathic surgery (n=1) and orthodontic treatment (n=7). Three of the patients refused further treatment. CONCLUSIONS: Open reduction for bilateral condylar head fractures presented an overall better functional and radiographic outcome, with higher patient satisfaction if condylar fracture segments were still feasible for rigid fixation.

Low molecular weight heparin for prevention of microvascular occlusion in digital replantation.

BACKGROUND: The success of digital replantation is highly dependent on the patency of the repaired vessels after microvascular anastomosis. Antithrombotic agents are frequently used for preventing vascular occlusion. Low molecular weight heparin (LMWH) has been reported to be as effective as unfractionated heparin (UFH) in peripheral vascular surgery, but with fewer adverse effects. Its benefit in microvascular surgery such as digital replantation is unclear. OBJECTIVES: To assess whether subcutaneous LMWH treatment improves the salvage rate of the digits in patients with digital replantation after traumatic amputation. SEARCH METHODS: The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (October 2012), CENTRAL (2012, Issue 10) and trials databases. In addition, the authors searched PubMed, CNKI (China National Knowledge Infrastructure) and CEPS (Chinese Electronic Periodical Services), and sought additional trials from reference lists of relevant publications. SELECTION CRITERIA: We selected randomised or quasi-randomised controlled trials of LMWH in patients who received digital replantation. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the risk of bias of the included trials. Disagreements were resolved by discussion. MAIN RESULTS: Two randomised trials involving 114 patients with at least 122 replanted digits met the inclusion criteria and were included. Both trials compared the efficacy and safety of LMWH with UFH. We found no trials comparing LMWH with placebo or other anticoagulants. The data from the two included studies were insufficient for meta-analysis. The overall success rate of replantation did not differ between the LMWH and UFH groups, 92.3% versus 89.2% in one trial (risk ratio (RR) 1.03; 95% confidence interval (CI) 0.87 to 1.22) and 94.3% versus 94.15% in the other trial (RR 1.00; 95% CI 0.89 to 1.13). The incidence of both postoperative arterial and venous insufficiency were reported in one trial and did not significantly differ between the LMWH and UFH groups (RR 1.08; 95% CI 0.16 to 7.10 and RR 0.81; 95% CI 0.20 to 3.27, respectively). Direct and indirect causes of microvascular insufficiency were not reported in the trials. Different methods were used to monitor the adverse effects related to anticoagulation in the two trials. Bleeding tendency was monitored for the LMWH and UFH groups in one trial and was reported by the incidence of wound haemorrhage (11.5% versus 17.9%; RR 0.65; 95% CI 0.17 to 2.44), ecchymoses (3.8% versus 10.7%; RR 0.36; 95% CI 0.04 to 3.24), haematuria (3.8% versus 7.1%; RR 0.54; 95% CI 0.05 to 5.59), nasal bleeding (0% versus 7.1%; RR 0.21; 95% CI 0.01 to 4.28), gingival bleeding (0% versus 10.7%; RR 0.15, 95% CI 0.01 to 2.83) and faecal occult blood (0% versus 3.6%; RR 0.36; 95% CI 0.02 to 8.42). The bleeding tendency was increased in the UFH group but this was not statistically significant. This trial also monitored coagulability changes using parameters such as antithrombin activity, factor Xa activity, bleeding time, clotting time and activated partial thromboplastin time (aPTT). No comparison was made between the LMWH and UFH groups but all data consistently showed that coagulability was reduced more in the UFH group than in the LMWH group. The other trial reported a postoperative decrease in platelet count in the UFH group (preoperative 278.4 ± 18.7 x 10(9)/L, postoperative 194.3 ± 26.5 x 10(9)/L; P < 0.05) but not in the LMWH group (preoperative 260.8 ± 32.5 x 10(9)/L, postoperative 252.4 ± 29.1 x 10(9)/L; P > 0.05). AUTHORS' CONCLUSIONS: Current limited evidence based on two small-scaled low-to-medium quality randomised trials found no differences in the success rate of replantation between LMWH and UFH, but a lower risk of postoperative bleeding and hypocoagulability after the use of LMWH. Further well-designed and adequately powered clinical trials are warranted.

Improving Dental Implant Outcomes: CNN-Based System Accurately Measures Degree of Peri-Implantitis Damage on Periapical Film.

As the popularity of dental implants continues to grow at a rate of about 14% per year, so do the risks associated with the procedure. Complications such as sinusitis and nerve damage are not uncommon, and inadequate cleaning can lead to peri-implantitis around the implant, jeopardizing its stability and potentially necessitating retreatment. To address this issue, this research proposes a new system for evaluating the degree of periodontal damage around implants using Periapical film (PA). The system utilizes two Convolutional Neural Networks (CNN) models to accurately detect the location of the implant and assess the extent of damage caused by peri-implantitis. One of the CNN models is designed to determine the location of the implant in the PA with an accuracy of up to 89.31%, while the other model is responsible for assessing the degree of Peri-implantitis damage around the implant, achieving an accuracy of 90.45%. The system combines image cropping based on position information obtained from the first CNN with image enhancement techniques such as Histogram Equalization and Adaptive Histogram Equalization (AHE) to improve the visibility of the implant and gums. The result is a more accurate assessment of whether peri-implantitis has eroded to the first thread, a critical indicator of implant stability. To ensure the ethical and regulatory standards of our research, this proposal has been certified by the Institutional Review Board (IRB) under number 202102023B0C503. With no existing technology to evaluate Peri-implantitis damage around dental implants, this CNN-based system has the potential to revolutionize implant dentistry and improve patient outcomes.

Enlarging the deficient mandible.

The authors describe a technique to improve skeletal contours of the deficient mandible with normal occlusion using alloplastic implants, often in combination with chin lengthening or shortening. Successful outcomes depend on knowledge of normal facial skeletal relationships, appropriately designed biocompatible implants, and facility with craniofacial techniques.

Injectable insulin-lysozyme-loaded nanogels with enzymatically-controlled degradation and release for basal insulin treatment: In vitro characterization and in vivo observation.

Diabetes is a common global disease that causes immense suffering for individuals and huge costs for the health care system. To minimize complications such as organ degeneration, diabetic patients are required to undergo treatments to maintain the blood glucose level in the normal range, ideally mimicking normal insulin secretion. The normal physiological insulin secretion pattern in healthy individuals consists of a base (basal) level through the day and increased secretion after meals (bolus insulin). Thus effective treatments may combine long acting, low-level insulin therapy with boosts of short acting insulin and/or oral agents. To achieve long term management of basal insulin level, an injectable insulin-loaded gel composed of self-assembled nanoparticles from carboxymethyl-hexanoyl chitosan (CHC) and integrated lysozyme for controlled biodegradation and insulin release was developed. In vitro characterizations and evaluations confirmed that lysozyme was active on CHC and that the amount of lysozyme in a CHC hydrogel determined the degradation and insulin release rate. The degradation products were found to be highly cytocompatible using a cell assay. In vivo evaluation of the system in a diabetic mouse model revealed that the fasted blood glucose level could be maintained in the normal range for 10days with a single injection of insulin-loaded CHC-lysozyme gel. The insulin-loaded CHC-lysozyme gels clearly show promise for use as a novel injectable long-acting insulin delivery system, with potential to manage the basal insulin level for many days with a single injection.

Effect of bimaxillary rotational setback surgery on upper airway structure in skeletal class III deformities.

BACKGROUND: Upper airway narrowing has been a concern of mandibular setback. The aims of this study were (1) to evaluate the effect of bimaxillary rotational setback surgery on upper airway structure in patients with skeletal class III deformities, and (2) to compare the preoperative and postoperative upper airways of class III patients with age- and sex-matched class I control subjects. METHODS: The upper airways of 36 adults who consecutively underwent bimaxillary rotational setback surgery for skeletal class III deformities were assessed by means of cone-beam computed tomography before and at least 6 months after surgery. Results were compared with those of age- and sex-matched control subjects with skeletal class I structure. RESULTS: Before surgery, the class III patients had significantly larger velopharyngeal, oropharyngeal, and hypopharyngeal volumes than did the control subjects (all p < 0.01). The velopharyngeal, oropharyngeal, and hypopharynx volumes decreased significantly after surgery (all p < 0.01). The postoperative airways of class III patients were similar with regard to velopharyngeal, oropharyngeal, and hypopharyngeal volume (all p > 0.01) compared to control subjects. The postoperative velopharyngeal and oropharyngeal airway volumes were associated with the baseline airway volume (p < 0.001) and horizontal movement of the soft palate (p < 0.01). CONCLUSION: These results suggest that upper airway volume is decreased after bimaxillary rotational setback surgery for skeletal class III deformities, but is not smaller than in normal controls, and the postoperative upper airway volume is related to airway volume at baseline and changes in the surrounding structures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Osteoradionecrosis of the mandible after oromandibular cancer surgery.

Although postoperative radiotherapy has proved effective in improving local control and survival in patients with head and neck cancers, its complications, especially mandibular osteoradionecrosis, reduce the quality of life. Mandibular surgery before the radiotherapy adds an additional risk factor for osteoradionecrosis. This study reviews patients in Chang Gung Memorial Hospital, Taipei, Taiwan, over a 10-year period, who underwent intraoral cancer resection followed by postoperative radiotherapy and thereafter developed osteoradionecrosis of the mandible. A total of 24 men and three women with a mean age of 49.9 years were identified and included in the study. In 10 cases, tumor resection was performed with a marginal mandibulectomy; in eight cases, tumor resection was performed after mandibular osteotomy; and in three cases, a segmental mandibulectomy was performed, and the defect was reconstructed with a fibula osteoseptocutaneous flap. In six cases, tumor excisions were performed without interfering with the mandibular continuity. Patients received postoperative external beam radiotherapy into the primary site and the neck, with a mean dose (+/-SD) of 5900 +/- 1300 cGy in an average of 35 fractions during an average of 6.5 weeks. The average elapsed time between the end of radiation therapy and clinical diagnosis of osteoradionecrosis of the mandible was 11.2 months (range, 2 to 36 months). The time elapse between the end of the radiation therapy and the diagnosis of osteoradionecrosis was influenced by initial treatment (Kruskal-Wallis test: n = 27, chi-square = 12.884, p < 0.005), and this period was shorter if the mandibular osteotomy or marginal mandibulectomy was performed (the two lowest mean ranks in the test). However, if the initial surgery resulted in a segmental mandibulectomy reconstructed with a fibula osteoseptocutaneous flap, onset of the osteoradionecrosis was relatively late (Kruskal-Wallis test: n = 21, chi-square = 7.731, p = 0.052). After resection of osteoradionecrotic bone and surrounding soft tissue, 22 patients underwent reconstructive procedures with a fibula osteoseptocutaneous flap, and five patients underwent reconstructive procedures with an inferior genicular artery osteoperiosteal cutaneous flap. One fibula osteoseptocutaneous flap showed total failure and another showed a 25 percent skin loss; both were revised with pedicled flaps. The skin paddle of an inferior genicular artery flap was replaced with an anterolateral thigh flap because of anatomic variation of the skin vessel. Once the diagnosis of osteoradionecrosis is established, replacement of the dead bone and surrounding tissue with a vascularized free bone flap is inevitable, and a composite osteocutaneous free flap is a good option.

Surface modification of polycaprolactone scaffolds fabricated via selective laser sintering for cartilage tissue engineering.

Surface modified porous polycaprolactone scaffolds fabricated via rapid prototyping techniques were evaluated for cartilage tissue engineering purposes. Polycaprolactone scaffolds manufactured by selective laser sintering (SLS) were surface modified through immersion coating with either gelatin or collagen. Three groups of scaffolds were created and compared for both mechanical and biological properties. Surface modification with collagen or gelatin improved the hydrophilicity, water uptake and mechanical strength of the pristine scaffold. From microscopic observations and biochemical analysis, collagen-modified scaffold was the best for cartilage tissue engineering in terms of cell proliferation and extracellular matrix production. Chondrocytes/collagen-modified scaffold constructs were implanted subdermally in the dorsal spaces of female nude mice. Histological and immunohistochemical staining of the retrieved implants after 8 weeks revealed enhanced cartilage tissue formation. We conclude that collagen surface modification through immersion coating on SLS-manufactured scaffolds is a feasible scaffold for cartilage tissue engineering in craniofacial reconstruction.

Reinforced bioresorbable implants for craniomaxillofacial osteosynthesis in pigs.

Our aim was to design a new bioresorbable fixation device for craniomaxillofacial surgery based on reinforcement of fibres between 2 different polymers. The final device, the 2.8 mm polyglycolide fibre-reinforced-poly-l-lactide screw (PGA FR-PLLA; PLLA/PGA: 70%:30%), was evaluated for its mechanical properties and compared with a commercial resorbable device that was not reinforced with fibre. To model clinical conditions, a unilateral sagittal split ramus osteotomy fixation model in pigs was then used to compare the clinical effectiveness of the resorbable screw with that of a titanium screw in vivo, followed by 3-dimensional reconstructive imaging and histological analysis. Finally, an ex vivo biomechanical test was completed to investigate the immediate fixation stability of the newly designed screws. The PGA FR-PLLA screw resulted in clinical healing that was comparable to that of the titanium screw and was mechanically superior to the commercial device, indicating that the newly-developed screws have a potential clinical application.

Reconstruction of traumatic nasal deformity in Orientals.

PURPOSE: The application of rhinoplasty in the treatment of traumatic nasal deformity remains one of the most challenging problems for surgeons. Not only is the skeletal structure severely deformed, but the soft tissue may also be disfigured by a previous injury. Although autogenous bone and cartilage have been the primary choice for nasal reconstruction, synthetic material is desirable for various reasons. This article presents our experiences in the reconstruction of traumatic nasal deformity by using porous polyethylene (Medpor) implant in Orientals. MATERIALS AND METHODS: From May 1998 to January 2005, 32 patients, including 15 males and 17 females, underwent augmentation rhinoplasty for the correction of traumatic nasal deformity. Of these, 30 patients had experienced associated midfacial bone fractures. The surgical procedures employed consisted of the open-tip approach that was followed by implant carving, placement and fixation. Twenty patients received lateral nasal osteotomies, and septoplasty procedures were performed in nine patients, simultaneously. External taping was done, and nostril tampons were placed postoperatively and left in situ for 3 days. The outcome was assessed by an independent investigator and the patients themselves. RESULTS: The patients were, on average, 22 years old at the time of reconstruction and were followed up for an average period of 25.4 months. The interval from injury to the rhinoplasty procedure was 304 days, on average. The average length of dorsal grafts was 44.9 mm. The overall aesthetic-improvement rate was 90.6%, and the patient-satisfaction rate was 84.4%. There were three complications, including an implant-tip exposure and two implant infections. CONCLUSION: A porous polyethylene (Medpor) implant is an effective alternative to autograft for correction of traumatic nasal deformity in Orientals to achieve a pleasing appearance of the nose without donor-site morbidity. A meticulous execution of concomitant procedures and impregnation of the implant by submerging it in an antibiotics solution prior to use were helpful in decreasing the complications.

A safe and effective way for reduction of temporomandibular joint dislocation.

Anterior dislocation of the temporomandibular joint (TMJ) is a common problem which demands immediate reduction to relieve the discomfort. The most popular technique is to put the operator's thumbs over the molar teeth of the patient and push the dislocated jaw downward and backward. This maneuver takes a lot of effort and usually needs sedation. Failure to reduction is not uncommon. Furthermore, the physician has to take the risk of being bitten and disease transmission. A novel method for reduction of the dislocated TMJ via extraoral route is presented, based on the observation that once the mandible is dislocated anteriorly, the coronoid process and anterior border of the ramus can be palpated easily over the cheek. By applying steady pressure over this prominent part, the anteriorly dislocated mandible can be reduced easily. From May 2000 to July 2005, there were 7 anterior mandible dislocations treated successfully by this method in Chang Gung Memorial Hospital. None of the patients need any adjuvant medication for sedation or relaxation. This technique is simple and effective, and the physicians are spared from the risk of bite trauma and unexpected disease transmission.