Daniel Buchbinder

Primary Placement of Osseointegrated Implants in Microvascular Mandibular Reconstruction

The goal of mandibular reconstruction is to rehabilitate the patient by restoring occlusal relationships, lower facial contour, oral continence, and a denture-bearing surface. One of the major advantages of the use of vascularized bone over all other methods of mandibular reconstruction is its ability to achieve dental rehabilitation rapidly. The use of osseointegrated dental implants is a valuable adjunct in oral rehabilitation. It provides the most rigid form of stabilization to withstand the forces of mastication. In situations In which soft tissue reconstruction or the height of the alveolar ridge is not sufficient for a tissue-borne denture, implants offer the most suitable alternative. Mandibular reconstruction with free tissue transfer techniques is Ideally suited for the placement of implants. These can be inserted at the time of mandibular reconstruction. Four months after surgery, when the integration process has occurred, the implants are unroofed, loaded, and ready for prosthetic placement. We will present several representative patients who underwent mandibular reconstruction with microvascular free bone transfer who have been successfully rehabilitated by osseointegrated implants. The process of osseointegration, different types of dental implants, and issues regarding radiation and Implants are discussed. This is the first report of dental rehabilitation by primary placement of dental implants in patients undergoing microvascular mandibular reconstruction.

Functional mandibular reconstruction of patients with oral cancer

For the patient with oral cancer who has undergone quadrant resection, mandibular reconstruction provides normalization of the lower facial contour, regained architectural support, and reestablishment of occlusal relationships. Reconstruction with vascularized bone offers the most rapid rehabilitation. Replacement of dentition provides improved deglutition, mastication, and speech. In eligible patients the use of osteointegrated implants can provide rigid stabilization for dental prostheses. In previous studies these implants were placed in a secondary procedure. In the present study microvascular mandibular reconstruction was combined with primary placement of osteointegrated implants in the treatment of seven patients. Preliminary results indicate that the combination of procedures can provide more rapid and effective rehabilitation for the patient with cancer. Issues for further study are also identified.

Subcutaneous Mandibulotomy : A New Surgical Access for Large Tumors of the Parapharyngeal Space

Objectives: Surgery for tumors of the parapharyngeal space (PPS) requires adequate exposure to identify and protect vital structures. Transcervical and transcervical‐transparotid approaches to the PPS may be enhanced by mandibulotomy. However, midline mandibulotomy traditionally requires lip‐splitting and extensive intraoral incisions, often necessitating tracheostomy and nasogastric feeding. We describe a new technique to gain exposure to the PPS while avoiding these consequences. Study Design: Case series. Methods: Five patients with PPS tumors underwent surgery using a new technique, the subcutaneous mandibulotomy approach (SMA). Each case was retrospectively assessed for tumor size, intraoperative access to the PPS, perioperative complications, and length of hospitalization. Results: In this series, the additional exposure achieved by SMA was adequate to safely remove large PPS tumors that could not be delivered through the transcervical‐transparotid approach. All patients started oral diets on postoperative day 1 and were discharged within 3 days. There were no intraoperative complications, and postoperative complications were self‐limited. The pathologic entities were a venous malformation, a paraganglioma, and three large, deep‐lobe pleomorphic adenomas of the parotid. Conclusions: We introduce a new technique, the SMA, which affords excellent access to the PPS without the lip‐split, chin‐split, and floor of mouth incisions. The SMA avoids both nasogastric feeding and a tracheostomy and offers improved cosmesis compared with a traditional midline mandibulotomy. Our current stepwise approach to achieve exposure to the PPS includes use of the SMA as an intermediate step for extensive PPS lesions, which are inaccessible through the transcervical approach yet do not require full labiomandibulotomy for safe and complete removal.

Maxillofacial Pathology and Management of Pierre Robin Sequence

Pierre Robin sequence affects 1:8500 newborns and is characterized by cleft palate, micrognathia, and airway obstruction. Evolution in the understanding of the causes and pathogenesis of this condition is reviewed. Clinical findings and treatment options are also addressed. An overview of syndromes commonly associated with Pierre Robin sequence is provided.

Tongue flaps in maxillofacial surgery

The tongue provides well-vascularized tissue that can be used predictably in maxillofacial reconstruction. Pertinent surgical anatomy and the different designs and clinical applications of tongue flaps are presented. Clinical cases are discussed.

Periadventitial delivery of heparin in the prevention of microvenous thrombosis

PURPOSE In spite of advances in technique and instrumentation, microvascular free tissue transfer remains associated with a persistent risk of flap failure. The use of systemic anticoagulants to overcome the formation of vasoocclusive thrombi at reactive anastomotic sites is associated with a high rate of flap hematoma and is ill advised in the operative setting. The purpose of this study was to investigate the use of a biodegradable, nontoxic polymer gel (polyvinyl alcohol, PVA) to effect a sustained localized release of perivascular heparin around thrombogenic venous anastomoses. MATERIALS AND METHODS A modified adventitial inclusion model was created in the femoral vein of 64 adult female Sprague-Dawley rats. Animals were divided into four experimental groups: 1) no treatment (controls), 2) periadventitial PVA gel contained in a vicryl chamber, 3) periadventitial PVA gel mixed with heparin, and 4) systemic heparin (intravenous pump). Patency rates in the femoral vein were checked at 10 minutes, 1 hour, 1 day, and 4 days after surgery. Systemic coagulation parameters and histology (scanning electron microscopy, SEM) were assessed in representative animals from all groups. RESULTS Patency rates for experimental groups showed a significant improvement in animals treated with PVA/heparin and systemic heparin over controls. Wound hematomas occurred in 7 of 16 animals in group 3, and in 4 of 16 animals in group 4. Activated partial thromboplastin times were elevated in group 4 only (> 150 seconds). CONCLUSIONS Continuous release of periadventitial heparin using a polymeric delivery system may represent an efficient means of attenuating the reactivity of microvenous anastomoses without affecting systemic coagulation parameters. In this model, however, its use was associated with a high rate of local wound hematoma.

Tongue Strength as a Predictor of Functional Outcomes and Quality of Life after Tongue Cancer Surgery

Objectives: Surgical resection of oral cancer can result in altered speech, swallowing, and quality of life (QOL). To date, the oral outcome variables of tongue strength, tongue and jaw range of motion, and saliva production have not been extensively assessed. This pilot study was done to assess tongue strength along with other oral outcomes and their relationship to performance status for speech, swallowing, and QOL after partial glossectomy. Our aim was to create a norm for what should be considered a normal tongue strength value in this population. We hypothesized that patients with tongue strength of 30 kPa or greater would perform better on the performance status scale and various QOL measures than do patients with tongue strength of less than 30 kPa. Methods: We used a cross-sectional design in this study. The postoperative assessment included 1) Performance Status Scale and Karnofsky Performance Status Scale; 2) oral outcome variables of tongue strength, jaw range of motion, and saliva production; and 3) patient-rated QOL ratings via Eating Assessment Tool, M. D. Anderson Dysphagia Inventory, EORTC-H&N35, and Speech Handicap Index. Results: Patients with tongue strength of at least 30 kPa performed better on the performance status scales and various QOL measures. The cutoff score of 30 kPa for tongue strength measures revealed a trend in predicting performance on the scales and QOL measures. Conclusions: The oral outcome variables correlated with performance status for speech, swallowing, and QOL. We propose a norm for tongue strength in this population, based on the trend seen in this group of patients, as none previously existed. Future studies are under way that incorporate a larger sample size to further validate this norm. Future studies will also examine oral functional outcome measures in a larger population by including other oral and oropharyngeal sites to help predict speech and swallow performance status and QOL.

Computer-Assisted Implant Rehabilitation of Maxillomandibular Defects Reconstructed With Vascularized Bone Free Flaps

IMPORTANCE Functional recovery for patients who undergo maxillomandibular reconstruction with vascularized bone free flaps (VBFFs) is potentially more attainable with computer-assisted implant rehabilitation. This prosthodontic-driven approach uses software planning and surgical templates for implant placement supporting fixed dental prostheses (FDP). Implant success with immediate load (IL) provisional and definitive FDP restorations in VBFFs is reported for the first time in a patient cohort. OBJECTIVES To determine implant success for FDP restorations and IL restorations. To determine factors that may influence success and predictability to provide FDP restorations in VBFFs. DESIGN A retrospective medical chart review was conducted of patients who underwent VBFF reconstruction and computer-assisted planning (CP) for FDP implant rehabilitation. This study was conducted with approval from the institutional review board at Beth Israel Medical Center, New York, New York. SETTING Clinical procedures were conducted in operating room and outpatient facilities in a tertiary referral medical center. PARTICIPANTS Twenty-eight consecutive patient treatments were reviewed. Inclusion criteria for all patients were VBFF reconstruction and CP for FDP restoration prior to stage 1 implant surgery. Patients were evaluated for implant success, surgical templates, IL provisional restorations, and prosthodontic framework design. A comparison is made between patients with IL provisional restorations and those patients who did not receive an immediate restoration. MAIN OUTCOMES AND MEASURES Implants that achieved osseointegration and used for prosthetic reconstruction determined success. Prosthodontic design considerations included whether the patient received an IL provisional restoration and 3 categories of FDP metal framework design. RESULTS Ninety-nine implants of 116 implants placed were used for prosthetic restorations, achieving an 85.4% success rate. Twenty-five of 28 patients received FDP restorations. Thirteen of 28 patients received IL provisional restorations at stage 1 implant surgery. Fifty of 56 implants were successful (89.3%) in the IL group. CONCLUSIONS Computer-assisted implant rehabilitation of reconstructed defects can achieve superior results to provide FDP and IL provisional restorations. This prosthodontic-driven approach also uses unique framework design to account for mandible height discrepancy after fibula free flap reconstruction. Patient management for FDP rehabilitation is also dependent on radiation status, soft-tissue modification, and patient selection.

Microanatomic analysis of the medial antebrachial nerve as a potential donor nerve in maxillofacial grafting

PURPOSE To histologically compare the anterior branch of the medial antebrachial cutaneous nerve (MACN) with the sural nerve using biometric techniques. PATIENTS AND METHODS Twenty-centimeter segments of the right and left (MACN) and sural nerves from three cadavers were analyzed. The number of fascicles within the nerves were counted and the neural to connective tissue ratio was estimated. RESULTS Sural nerves consistently showed greater amounts of connective tissue between the fascicles than the MACN. Fascicle diameter varied less throughout the length of the MACN. Fascicle diameter varied less throughout the length of the MACN and it showed fewer and larger fascicles, more closely approximating the anatomy of the inferior alveolar nerve. CONCLUSION These preliminary data suggest that the MACN, on anatomic grounds, is theoretically more suited for grafting to the alveolar and lingual nerves than the sural nerve.

Lag screw fixation of a nonstable zygomatic complex fracture : Case report

Fractures of the zygomatic complex and their treatment have been the focus of much attention in the last 30 years. Treatment frequently depends on the surgical findings, experience, and discretion of the surgeon. Treatment of zygomatic complex (ZMC) fractures often requires stabilization at the frontozygomatic (FZ) suture. Frodel’ and Marentette’ have described the use of lag screw fixation of the midfacial skeleton, including the FZ area. The purpose of this report is to describe the use of lag screw fixation of the FZ suture for cases of ZMC fractures in which fixation in this location is necessary.