Repair of complex ovine segmental mandibulectomy utilizing customized tissue engineered bony flaps.

Craniofacial defects require a treatment approach that provides both robust tissues to withstand the forces of mastication and high geometric fidelity that allows restoration of facial architecture. When the surrounding soft tissue is compromised either through lack of quantity (insufficient soft tissue to enclose a graft) or quality (insufficient vascularity or inducible cells), a vascularized construct is needed for reconstruction. Tissue engineering using customized 3D printed bioreactors enables the generation of mechanically robust, vascularized bony tissues of the desired geometry. While this approach has been shown to be effective when utilized for reconstruction of non-load bearing ovine angular defects and partial segmental defects, the two-stage approach to mandibular reconstruction requires testing in a large, load-bearing defect. In this study, 5 sheep underwent bioreactor implantation and the creation of a load-bearing mandibular defect. Two bioreactor geometries were tested: a larger complex bioreactor with a central groove, and a smaller rectangular bioreactor that were filled with a mix of xenograft and autograft (initial bone volume/total volume BV/TV of 31.8 ± 1.6%). At transfer, the tissues generated within large and small bioreactors were composed of a mix of lamellar and woven bone and had BV/TV of 55.3 ± 2.6% and 59.2 ± 6.3%, respectively. After transfer of the large bioreactors to the mandibular defect, the bioreactor tissues continued to remodel, reaching a final BV/TV of 64.5 ± 6.2%. Despite recalcitrant infections, viable osteoblasts were seen within the transferred tissues to the mandibular site at the end of the study, suggesting that a vascularized customized bony flap is a potentially effective reconstructive strategy when combined with an optimal stabilization strategy and local antibiotic delivery prior to development of a deep-seated infection.

Retrospective Cohort Study on the Management of Diffuse Deep Neck Space Infections Using a Modified Submental Approach and Placement of Wound Vacuum.

PURPOSE: Diffuse deep neck space infection (DDNSI) is an emergent condition that requires efficient surgical and airway management. A novel surgical approach has been developed to enhance access and improve visualization of the involved deep neck spaces, which allows for better evaluation of the extent of tissue necrosis. This study will compare the treatment of DDNSI with traditional incision and drainage with drain placement (Conventional) versus the new incision and drainage design with the use of a wound vacuum (VAC). METHODS: This retrospective cohort study was performed on DDNSI cases treated with the VAC versus Conventional techniques from July 2014 to September 2020 at Memorial Hermann Hospital by the oral and maxillofacial surgery service. To be categorized as a DDNSI, the patient had to demonstrate radiographic evidence of an infection bilaterally in a minimum of four spaces, such as bilateral submandibular, sublingual, and submental spaces. Primary predictor variable was treatment method for DDNSI, Conventional versus VAC. Primary outcome variables were hospital length of stay (LOS), number of washouts, and days of intubation. Covariates were age, sex, number of spaces involved, presence of necrotic tissues, comorbidities, and mortality. Appropriate uni- and bi-variate statistics were calculated. Statistical significance was set at P < .05. RESULTS: Fifty-one patients (17 female and 34 male) aged 18 to 65 years were treated for DDNSI. Twenty-eight patients were treated using the VAC approach and 23 patients were treated with the conventional approach. The average LOS 8.3 ± 0.8 days (P-value = .0001), number of days intubated 3 ± 0.3 (P-value = .0001), and number of required washouts 2 ± 0.2 (P-value = .004) were statistically lower in the VAC group compared to the Conventional group. CONCLUSIONS: There were significant improvements encountered with overall length of hospital stay, number of days intubated, and the number of required wash outs. There were significant differences in outcomes between patients with comorbidities when compared to those who had none.

Management of Trigeminal Neuralgia with Botulinum Toxin Type A: Report of Two Cases.

Trigeminal neuralgia is a chronic pain condition associated with sharp, shock-like pain in one or more divisions of the trigeminal nerve. For patients who do not respond well to pharmacotherapy, there is growing evidence that Botulinum toxin type A injections into the trigeminal ganglion provide pain relief for several weeks up to several months at a time. One option is to administer injections into the trigeminal ganglion in Meckel's cave by inserting a needle through the Pterygopalatine Fossa using fluoroscopy to guide and confirm the proper needle placement. However, there is evidence that Botulinum toxin travels across nerve synapses; thus, injecting directly into the trigeminal ganglion may not be necessary. We present two patients with a confirmed diagnosis of trigeminal neuralgia who were treated by injecting Botulinum toxin type A intraorally into the mental foramen which resulted in 6 months or longer of pain relief. Injections into the mental foramen are much easier to administer than those administered directly into the trigeminal ganglion, and both patients treated with this technique experienced comparable results to what can be expected from traditional fluoroscopy-guided botulinum toxin injections. Though more research is needed, these cases potentially imply that a less-invasive injection may be sufficient in managing trigeminal neuralgia-related pain.

Successful Treatment of Myofascial Pain Syndrome (MPS) with Surgical Cauterization of Temporalis Muscle Trigger Points: A Case Report.

For patients suffering from myofascial pain syndrome (MPS) affecting muscles of mastication, traditional trigger point therapy treatment regimens can prove inconvenient, due to the short duration of pain relief after each injection and expense of repeated visits which are often not covered by insurance. We present a case of a patient treated using an alternative technique that could develop into an additional modality for treating MPS patients who are refractory to conservative treatment. This technique involves identifying and marking the patient's trigger points and surgically cauterizing each location using a Bovie electrosurgical unit. While traditional trigger point injection therapy for myofascial pain syndrome is a well-described technique with acceptable pain relief expected for a period of 8-12 weeks, this technique provided up to 24 months of adequate pain relief in a patient. While further studies are indicated before widespread adoption can be recommended, this patient's response suggests that this technique may be useful in offering longer-term pain relief compared with trigger point injection therapy.

The Epidemiology and Management of Pediatric Maxillary Fractures.

BACKGROUND: Most literature regarding traumatic Le Fort or maxillary fractures exists in the adult population, with limited information regarding the epidemiology and management of pediatric fractures. The purpose of this study was to evaluate fracture mechanism, surgical management, and associated injuries in pediatric patients with Le Fort fractures. METHODS: A retrospective chart analysis of all pediatric patients age ≤18 years diagnosed with facial fractures at a single level 1 trauma center over a 10-year period (January 2006-December 2015) was performed. Demographics, fracture location, mechanism of injury, and hospital course were abstracted as well as associated injuries and need for operative management. RESULTS: A total of 1274 patients met inclusion criteria. Sixty-nine (5.4%) presented with Le Fort fractures. Factors associated with Le Fort fractures included motor vehicle collisions (P < 0.001), increased age (P < 0.001), and traumatic brain injury (P < 0.04). Patients with Le Fort fractures were more likely to need intensive care unit admission (P < 0.001), surgical management (P < 0.001), transfusions (P < 0.001), secondary fixation surgery (P < 0.001), and have a longer length of stay (P < 0.001). Multivariate showed increased odds for increased age (OR 1.1; 95%CI 1.04-1.17) and concomitant orbit fractures (OR 8.33; 95%CI 4.08-19.34). Decreased odds were associated for all mechanisms of injury other than motor vehicle collisions (Other blunt trauma: OR 0.36; 95%CI 0.2-0.6. Penetrating trauma: OR 0.13; 95%CI 0.01-0.6). CONCLUSION: Maxillary or Le Fort fractures represent a small portion of pediatric facial fractures but require high rates of operative management. The high velocity required to create this fracture type is associated with significant traumatic comorbidities, which can complicate the hospital course.

Localized mandibular infection affects remote in vivo bioreactor bone generation.

Mandibular reconstruction requires functional and aesthetic repair and is further complicated by contamination from oral and skin flora. Antibiotic-releasing porous space maintainers have been developed for the local release of vancomycin and to promote soft tissue attachment. In this study, mandibular defects in six sheep were inoculated with 106 colony forming units of Staphylococcus aureus; three sheep were implanted with unloaded porous space maintainers and three sheep were implanted with vancomycin-loaded space maintainers within the defect site. During the same surgery, 3D-printed in vivo bioreactors containing autograft or xenograft were implanted adjacent to rib periosteum. After 9 weeks, animals were euthanized, and tissues were analyzed. Antibiotic-loaded space maintainers were able to prevent dehiscence of soft tissue overlying the space maintainer, reduce local inflammatory cells, eliminate the persistence of pathogens, and prevent the increase in mandibular size compared to unloaded space maintainers in this sheep model. Animals with an untreated mandibular infection formed bony tissues with greater density and maturity within the distal bioreactors. Additionally, tissues grown in autograft-filled bioreactors had higher compressive moduli and higher maximum screw pull-out forces than xenograft-filled bioreactors. In summary, we demonstrated that antibiotic-releasing space maintainers are an innovative approach to preserve a robust soft tissue pocket while clearing infection, and that local infections can increase local and remote bone growth.

Answering the Call: How to Establish a Dentoalveolar Surgery Mission in Low- and Middle-Income Countries.

Addressing access to oral health care in many low- to middle-income countries is a complicated issue. Oral and maxillofacial surgeons may help engage with vulnerable populations through carefully planned dentoalveolar mission trips. The process of planning a mission includes selecting a population and identifying their unique needs, designing clinic layouts and workflows, team preparation, collection of supplies, fundraising, and advertising. During the mission, methods for protecting privacy, delivering treatment that is standard of care, and sanitation/sterilization options are reviewed. Ethical considerations include avoiding exploitation of vulnerable populations, offending local hosts, need for data collection, and long-term mission sustainability.

The Effect of Deep Vein Thrombosis Prophylaxis on Bleeding in Periorbital Surgery in Trauma Patients.

The aim of this study is to assess if there is an increase in postoperative venous thromboembolism (VTE) or bleeding complications in patients who received perioperative chemical thromboprophylaxis compared with patients in whom chemical thromboprophylaxis was held during periorbital trauma surgery. This is a retrospective chart review of patients undergoing periorbital surgery treated in three different city hospitals, by the Department of Oral and Maxillofacial Surgery, University of Texas, between August 2014 and December 2016. A total of 237 patients were included in this study. None of these patients suffered a postoperative VTE. A total of 102 patients received perioperative pharmacologic thromboprophylaxis in the form of enoxaparin or heparin. In this group, one patient suffered a buccal space hematoma. Chemical thromboprophylaxis was held in 135 patients preoperatively and for at least 24 hours postoperatively. In this group, one patient suffered a retrobulbar hematoma after repair of an orbital floor fracture. The rate of postoperative bleeding complications was compared by the chi-square test and was not statistically significant ( p = 0.8417).

Surgical Navigation for Oral and Maxillofacial Surgery.

This article reviews the basic setup and function of surgical navigation and displays a variety of applications in oral and maxillofacial surgery. The use of surgical navigation for dental implant placement is discussed elsewhere in this issue.

Intracranial Approach for Retrieval of the Condylar Head After Avulsion into the Middle Cranial Fossa.

BACKGROUND: Dislocation of the mandibular condyle into the middle cranial fossa is a rare injury that can be seen after facial trauma. Early identification of condyle dislocation into the middle cranial fossa was difficult until the development of computed tomography, and diagnosis was often significantly delayed after the initial trauma. CASE DESCRIPTION: We present a rare case of a young woman who presents after a mechanical fall resulting in facial trauma with an avulsion condyle fracture with dislocation of the mandibular condyle into the middle cranial fossa. CONCLUSIONS: To our knowledge, this complete avulsion of the condyle into the middle cranial fossa requiring an intracranial approach for condylectomy is extremely rare. We discuss the surgical management options for reduction and fixation accomplished in a multidisciplinary approach involving neurosurgery and oral maxillofacial surgery.

Factors Associated With Surgical Management for Pediatric Facial Fractures at a Level One Trauma Center.

Pediatric facial fractures present and are managed differently than the adult population. This study describes the pattern and mechanism of facial fractures in children and identifies factors associated with need for surgical management. An IRB-approved retrospective chart analysis of all pediatric patients age ≤ 18 years diagnosed with facial fractures at our level 1 trauma center over a 10-year period (January 2006-December 2015) was performed. Demographics, fracture location, mechanism of injury, concomitant head and neck injuries, and surgical management were reviewed. Statistical analysis was then performed comparing surgical and nonsurgical cohorts using univariate and multivariate analyses. One thousand two hundred seventy-four patients were diagnosed with facial fractures. Five hundred seventeen (40.6%) underwent surgical management. Two thousand one hundred seventy-two total facial fractures were recorded. Orbit fractures (29%) were the most commonly recorded, observed in 49% of patients presenting. Increased age was associated with increased odds of surgical management (OR 1.13; 95% CI 1.09-1.16). Mandible (OR 9.28; 95% CI 6.88-12.51) and Le Fort fractures (OR 19.73; 95% CI 9.78-39.77) had increased odds of surgical management. Patients with traumatic brain injury had reduced odds (OR 0.54; 95% CI 0.35-0.83) of surgical management for their facial fractures. Older pediatric patients may be more likely to require surgical management of their facial fractures, especially those with mandible or Le Fort fractures. Patients with traumatic brain injury are likely to sustain life threatening injuries, deferring repair of their facial fractures. Patient education and counseling, as well as predictive models, can be improved to reflect these data.

The Trends of Pediatric Facial Fractures Due to Violence in a Level One Trauma Population.

INTRODUCTION: Pediatric facial fractures due to intentionally violent mechanisms represent a unique subset of facial fractures. The objective of our research is to identify how violence affects patterns of facial fractures and their management in pediatric patients. METHODS: An IRB approved, retrospective study of our institution's pediatric patients ≤18 years of age who presented with ≥1 facial fracture due to violence from January 2006 to December 2015 was performed. Violence was defined as trauma intended to hurt another or self. Demographics, fractures, mechanism, concomitant injuries, and management were analyzed. RESULTS: The 1274 patients were diagnosed with facial fractures, with 235 of these due to violence (18%). These patients of violence (POV) had 332 fractures, with an average fracture per patient of 1.4 ±â€Š.0.8. The majority (86%) were male, Non-Hispanic African American (35%), and the average age was 15.9 ±â€Š2.8 years. The most common fracture was the mandible (50% of patients) and most common mechanism was assault (76%). The POV were older, male, and of minority race/ethnic groups when compared to patients of non-violence (PONV) (P <0.01). The POV presented with fewer concomitant injuries, were less likely to be admitted to the intensive care unit, and more often surgically managed when compared to the PONV (P <0.01). CONCLUSION: This study represents the largest US, single institution, Level 1 trauma center study of pediatric facial fractures. Pediatric patients with facial fractures due to a violent mechanism represent a distinct category of trauma patients with a unique profile of injuries.

Biomaterials-aided mandibular reconstruction using in vivo bioreactors.

Large mandibular defects are clinically challenging to reconstruct due to the complex anatomy of the jaw and the limited availability of appropriate tissue for repair. We envision leveraging current advances in fabrication and biomaterials to create implantable devices that generate bone within the patients themselves suitable for their own specific anatomical pathology. The in vivo bioreactor strategy facilitates the generation of large autologous vascularized bony tissue of customized geometry without the addition of exogenous growth factors or cells. To translate this technology, we investigated its success in reconstructing a mandibular defect of physiologically relevant size in sheep. We fabricated and implanted 3D-printed in vivo bioreactors against rib periosteum and utilized biomaterial-based space maintenance to preserve the native anatomical mandibular structure in the defect site before reconstruction. Nine weeks after bioreactor implantation, the ovine mandibles were repaired with the autologous bony tissue generated from the in vivo bioreactors. We evaluated tissues generated in bioreactors by radiographic, histological, mechanical, and biomolecular assays and repaired mandibles by radiographic and histological assays. Biomaterial-aided mandibular reconstruction was successful in a large superior marginal defect in five of six (83%) sheep. Given that these studies utilized clinically available biomaterials, such as bone cement and ceramic particles, this strategy is designed for rapid human translation to improve outcomes in patients with large mandibular defects.

Invasive Cutaneous Facial Mucormycosis in a Trauma Patient.

Mucormycosis, also known as zygomycosis, is an aggressive infection caused by a ubiquitous group of molds known as mucormycetes and is often associated with immune suppression or trauma among immunocompetent populations. We present the case of a 19-year-old woman who was involved in a motor vehicle accident in whom rapidly progressive invasive cutaneous facial mucormycosis subsequently developed. The diagnosis, treatment options, and incidence of this disease process are discussed in the context of trauma.

Characteristics, length of stay, and hospital bills associated with severe odontogenic infections in Houston, TX.

BACKGROUND: There were 2 main purposes of this retrospective chart review study. The first was to describe the demographic, social, and financial characteristics of patients with severe odontogenic infections. The second was to assess the relationships among several demographic, social, and treatment variables and length of stay (LOS) in the hospital and hospital bill (charges). METHODS: The authors conducted a retrospective chart review for patients admitted to the hospital and taken to the operating room for treatment of severe odontogenic infections at 3 hospitals in Houston, TX (Ben Taub, Memorial Hermann Hospital, and Lyndon B. Johnson) from January 2010 through January 2015. RESULTS: The authors included data from severe odontogenic infections in 298 patients (55% male; mean age, 38.9 years) in this study. In this population, 45% required admission to the intensive care unit, and the mean LOS was 5.5 days. Most patients (66.6%) were uninsured. The average cost of hospitalization for this patient population was $13,058, and the average hospital bill was $48,351. At multivariable analysis, age (P = .011), preadmission antibiotic use (P = .012), diabetes mellitus (P = .004), and higher odontogenic infection severity score (P < .001) were associated with increased LOS. Higher odontogenic infection severity score, diabetes mellitus, and an American Society of Anesthesiologists score of 3 or more were associated with an increased charge of hospitalization. CONCLUSIONS: Severe odontogenic infections were associated with substantial morbidity and cost in this largely unsponsored patient population. The authors identified variables associated with increased LOS and charge of hospitalization. PRACTICAL IMPLICATIONS: Clinicians should consider these findings in their decision-making processes and prioritize early treatment of odontogenic infections potentially to decrease the number of patients admitted to the hospital, LOS, and overall costs of treatment for these infections.

Reconstruction of large mandibular defects using autologous tissues generated from in vivo bioreactors.

Reconstruction of large mandibular defects is clinically challenging due to the need for donor tissue of appropriate shape and volume to facilitate high fidelity repair. In order to generate large vascularized tissues of custom geometry, bioreactors were implanted against the rib periosteum of 3-4year-old sheep for nine weeks. Bioreactors were filled with either morcellized autologous bone, synthetic ceramic particles, or a combination thereof. Tissues generated within synthetic graft-filled bioreactors were transferred into a large right-sided mandibular angle defect as either avascular grafts (n=3) or vascularized free flaps (n=3). After twelve additional weeks, reconstructed mandibular angles were harvested and compared to contralateral control angles. Per histologic and radiologic evaluation, a greater amount of mineralized tissue was generated in bioreactors filled with autologous graft although the quality of viable bone was not significantly different between groups. Genetic analyses of soft tissue surrounding bioreactor-generated tissues demonstrated similar early and late stage osteogenic biomarker expression (Runx2 and Osteocalcin) between the bioreactors and rib periosteum. Although no significant differences between the height of reconstructed and control mandibular angles were observed, the reconstructed mandibles had decreased bone volume. There were no differences between mandibles reconstructed with bioreactor-generated tissues transferred as flaps or grafts. Tissues used for mandibular reconstruction demonstrated integration with native bone as well as evidence of remodeling. In this study, we have demonstrated that synthetic scaffolds are sufficient to generate large volumes of mineralized tissue in an in vivo bioreactor for mandibular reconstruction. STATEMENT OF SIGNIFICANCE: A significant clinical challenge in craniofacial surgery is the reconstruction of large mandibular defects. In this work, we demonstrated that vascularized tissues of large volume and custom geometry can be generated from in vivo bioreactors implanted against the rib periosteum in an ovine model. The effects of different bioreactor scaffold material on tissue ingrowth were measured. To minimize donor site morbidity, tissues generated from bioreactors filled with synthetic graft were transferred as either vascularized free flaps or avascular grafts to a large mandibular defect. It was demonstrated that synthetic graft in an in vivo bioreactor is sufficient to produce free tissue bone flaps capable of integrating with native tissues when transferred to a large mandibular defect in an ovine model.

'Cytology-on-a-chip' based sensors for monitoring of potentially malignant oral lesions.

UNLABELLED: Despite significant advances in surgical procedures and treatment, long-term prognosis for patients with oral cancer remains poor, with survival rates among the lowest of major cancers. Better methods are desperately needed to identify potential malignancies early when treatments are more effective. OBJECTIVE: To develop robust classification models from cytology-on-a-chip measurements that mirror diagnostic performance of gold standard approach involving tissue biopsy. MATERIALS AND METHODS: Measurements were recorded from 714 prospectively recruited patients with suspicious lesions across 6 diagnostic categories (each confirmed by tissue biopsy -histopathology) using a powerful new 'cytology-on-a-chip' approach capable of executing high content analysis at a single cell level. Over 200 cellular features related to biomarker expression, nuclear parameters and cellular morphology were recorded per cell. By cataloging an average of 2000 cells per patient, these efforts resulted in nearly 13 million indexed objects. RESULTS: Binary "low-risk"/"high-risk" models yielded AUC values of 0.88 and 0.84 for training and validation models, respectively, with an accompanying difference in sensitivity+specificity of 6.2%. In terms of accuracy, this model accurately predicted the correct diagnosis approximately 70% of the time, compared to the 69% initial agreement rate of the pool of expert pathologists. Key parameters identified in these models included cell circularity, Ki67 and EGFR expression, nuclear-cytoplasmic ratio, nuclear area, and cell area. CONCLUSIONS: This chip-based approach yields objective data that can be leveraged for diagnosis and management of patients with PMOL as well as uncovering new molecular-level insights behind cytological differences across the OED spectrum.

Osteomyelitis of the Mandible in an Adolescent.

A 13-year-old female, who had been experiencing episodes of mandibular pain and swelling for approximately six months, was referred to a university urgent care dental clinic for evaluation after receiving endodontic treatment. At the referral examination, clinical and radiographic findings were suggestive of osteomyelitis. The purpose of this report is to present the possible etiology, clinical and radiographic findings and surgical management of mandibular osteomyelitis in an adolescent patient.

Interobserver agreement in dysplasia grading: toward an enhanced gold standard for clinical pathology trials.

OBJECTIVE: Interobserver agreement in the context of oral epithelial dysplasia (OED) grading has been notoriously unreliable and can impose barriers for developing new molecular markers and diagnostic technologies. This paper aimed to report the details of a 3-stage histopathology review and adjudication process with the goal of achieving a consensus histopathologic diagnosis of each biopsy. STUDY DESIGN: Two adjacent serial histologic sections of oral lesions from 846 patients were independently scored by 2 different pathologists from a pool of 4. In instances where the original 2 pathologists disagreed, a third, independent adjudicating pathologist conducted a review of both sections. If a majority agreement was not achieved, the third stage involved a face-to-face consensus review. RESULTS: Individual pathologist pair κ values ranged from 0.251 to 0.706 (fair-good) before the 3-stage review process. During the initial review phase, the 2 pathologists agreed on a diagnosis for 69.9% of the cases. After the adjudication review by a third pathologist, an additional 22.8% of cases were given a consensus diagnosis (agreement of 2 out of 3 pathologists). After the face-to-face review, the remaining 7.3% of cases had a consensus diagnosis. CONCLUSIONS: The use of the defined protocol resulted in a substantial increase (30%) in diagnostic agreement and has the potential to improve the level of agreement for establishing gold standards for studies based on histopathologic diagnosis.