Virtual Surgical Planning and Stereolithography-guided Osteotomy for 3 Dimensional Mandibular Reconstruction with Free Fibula Osseous Flaps: A Case Report.

The osseous or osteocutaneous free fibula flap has become the gold standard for most mandibular reconstructions because of its favorable osseous characteristics. However, disadvantages, such as the time-consuming reconstructive step, difficulty in performing the osteotomies to precisely recreate the shape of the missing segment of mandible and poor bone-to-bone contact play a role in making the surgeons look for alternative flaps. With the advent of computerized design software, which accurately plans complex 3-dimensional reconstructions, has become a process that is more efficient and precise. However, the ability to transfer the computerized plan into the surgical field with stereolithographic models and guides has been a significant development in advancing reconstruction in the maxillofacial regions. The ability to "pre-plan" the case, mirror and superimpose natural structures into diseased and deformed areas, as well as the ability to reproduce these plans with good surgical precision has decreased overall operative time, and has helped facilitate functional and esthetic reconstruction. We describe a complex case treated with this technique, showing the power and elegance of computer assisted maxillofacial reconstruction from the University of Michigan, Oral and Maxillofacial Surgery.ope

Validation of a fibula graft cutting guide for mandibular reconstruction: experiment with rapid prototyping mandible model

Objective: We examined whether cutting a fibula graft with a surgical guide template, prepared with computer-aided design/computer-aided manufacturing (CAD/CAM), would improve the precision and accuracy of mandibular reconstruction. Methods: Thirty mandibular rapid prototype (RP) models were allocated to experimental (N = 15) and control (N = 15) groups. Thirty identical fibular RP models were assigned randomly, 15 to each group. For reference, we prepared a reconstructed mandibular RP model with a three-dimensional printer, based on surgical simulation. In the experimental group, a stereolithography (STL) surgical guide template, based on simulation, was used for cutting the fibula graft. In the control group, the fibula graft was cut manually, with reference to the reconstructed RP mandible model. The mandibular reconstructions were compared to the surgical simulation, and errors were calculated for both the STL surgical guide and the manual methods. Results: The average differences in three-dimensional, minimum distances between the reconstruction and simulation were 9.87 ± 6.32 mm (mean ± SD) for the STL surgical guide method and 14.76 ± 10.34 mm (mean ± SD) for the manual method. Discussion: The STL surgical guide method incurred less error than the manual method in mandibular reconstruction. A fibula cutting guide improved the precision of reconstructing the mandible with a fibula graft.ope

Non-invasive Mucormycosis Associated with Ameloblastoma of the Mandible in Liver Transplant Patients

Mucormycosis is an aggressive opportunistic fungal infection that can be found in the oral cavity. The fungus usually affects the immunocompromised patients and tends to invade and block blood vessels, resulting in significant tissue necrosis and invasive mucormycosis. However, a non-invasive form of mucormycosis is mostly asymptomatic and found accidentally in the immunocompetent normal hosts, manifested by localized overgrowth of the fungus. Here, we report a rare case of asymptomatic non-invasive mucormycosis of the mandible that was incidentally diagnosed in wide resection specimen of liver transplant patient who had previously underwent surgery of excision and simultaneous alloplastic bone graft due to mandibular ameloblastoma. Histopathological examination of the specimen revealed that there was neither vasculitis nor tissue necrosis, but numerous fungal hyphae were located only within the alloplastic graft materials in decalcified tissue sections. Awareness of the possibility of life-threatening mucormycosis in immunocompromised patients should be emphasized because it can be inactive or reactivated depending on the immune state of patients.ope

Lingual Cyst with Columnar Epithelium in an Adult : A Case Report

Lingual cyst is a clinical term indicating a cyst occurring within the tongue. Various disease may clinically present as a lingual cyst, such as foregut cyst, dermoid cyst, thyroglossal duct cyst, salivary duct cyst, hemangioma and ranula. In general, lingual cysts are asymptomatic but may cause airway obstruction, feeding or swallowing problems. Most of these lesions can be simply treated by surgical excision with good postoperative healing and low recurrence rate. Apart from that, histopathological diagnosis of the lesion is important because it means the origin of the lesion. Thus it is important to rule out several origins of lingual cyst histopathologically, because it might be related with adjacent anatomical structure or may indicate cysts on other sites. Herein, we reported a case of lingual cyst with columnar epithelium at the ventral tongue of a 46-year old man and reviewed the clinical and histopathological considerations required for further classification in lingual cysts.ope

Use of the pedicled buccal fat pad in the reconstruction of intraoral defects: a report of five cases.

The buccal fat pad is specialized fat tissue located anterior to the masseter muscle and deep to the buccinator muscle. Possessing a central body and four processes it provides separation allowing gliding motion between muscles, protects the neurovascular bundles from injuries, and maintains facial convexity. Because of its many advantageous functions, the use of the buccal fat pad during oral and maxillofacial procedures is promoted for the reconstruction of defects secondary to tumor resection, and those defects resulting from oroantral fistula caused by dento-alveolar surgery or trauma. We used the pedicled buccal fat pad in the reconstruction of intraoral defects such as oroantral fistula, maxillary posterior bone loss, or defects resulting from tumor resection. Epithelization of the fat tissue began 1 week after the surgery and demonstrated stable healing without complications over a long-term period. Thus, we highly recommend the use of this procedure.ope

Handheld Near-Infrared Fluorescence Imaging Device Using Modified Action Cameras for Peri-Operative Guidance of Microvascular Flap Surgery

Indocyanine green near-infrared fluorescence (ICG-NIRF) imaging has recently come into use as a novel method in peri-operative microvascular flap assessment. However, a majority of the many commercial devices launched for clinical use lack mobility, portability, and cost-efficiency and are thus unsuitable for intra-oral applications. This study introduces a cost-effective, customized, handheld NIRF device following principles of ICG-NIRF imaging. Moreover, the novel characteristics of our prototype, considered in conjunction with a literature review highlighting the significance of fluorescence devices in microvascular surgery, point to a new generation of devices for use in microvascular flap surgery.ope

Condyle dislocation following mandibular reconstruction using a fibula free flap: complication cases

Background: Condylar dislocation can arise as a complication in patients who required mandibular and/or condylar reconstruction and were operated on with fibula free flap (FFF) using surgical guides designed using simulation surgery. Surgeons should be aware of the complications in these present cases when planning and performing reconstructions as well as predicting prognoses. Cases presentation: Two cases showed condylar dislocation in mandibular reconstruction using a FFF fixed with a reconstruction plate. Three cases showed condylar dislocation in mandibular reconstruction using a fibula free flap fixed with a mini-plate. Conclusion: Despite the lack of clinical symptoms in these cases following mandibular reconstruction using an FFF, the mandibular condyle was severely displaced away from the glenoid fossa. A surgeon must have sufficient time to consider the use of a long flap with thickness similar to that of the mandible, ways to minimize span and bending, and methods of fixation. The patient, moreover, should be educated on condylar dislocation. Customized CAD/CAM-prototyped temporomandibular condyle-connected plates may be a good alternative even if virtual simulation surgery is to be performed before surgery. These considerations may help reduce the incidence of complications after mandibular reconstruction.ope

ccuracy of preoperative assessments for cervical lymph node metastasis in oral cancer

Purpose : The aim of this study was to determine the accuracy of clinical and radiologic assessments in detecting positive cervical lymph nodes in oral cancer. Materials and Methods : We had reviewed the preoperative clinical, radiologic and postoperative histopathologic reports of 46 patients who had been diagnosed as oral cancer and underwent surgical excision combined with neck dissection (52 sides of neck) in the Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University from the July 1, 1992 to the April 30, 1999. Results : The results were as follows 1. The male to female ratio was 4.38 : 1 and the mean age was 57. 2. Sensitivity values for the preoperative assessment of cervical lymph node metastasis in oral cancer were 62.5 % in clinical examination and 50.0 % in radiologic assessments. Specificity values were 77.8 % in clinical examination and 94.4 % in radiologic assessments. 3. False positive values were 44.4 % in clinical examination and 20.0 % in radiologic assessments. False negative values were 17.6 % in clinical and 19.0% in radiologic assessments. 4. Overall efficiency values were 73.1 % in clinical examination and 80.8 % in radiologic assessments. Summary : There were some limits on the accuracy of clinical and radiologic assessments in the preoperative detection of the cervical lymph nodes in oral cancer. To improve the accuracy, it is important to communicate between clinician and radiologist, and adjunctive diagnostic measures, ultrasound and fine needle aspiration cytology, were helpful increasing the overall efficiency. In the high risk sites (oral tongue and floor of the mouth) the false negative value is higher and the overall efficiency in radiologic evaluation is lower than those of the low risk sites (gingiva and alveolar ridge, retromolar trigone and buccal mucosa). The elective neck dissection should be considered in the high risk sites.ope

Chios mastic gum extracts as a potent antitumor agent that inhibits growth and induces apoptosis of oral cancer cells.

PURPOSE: The purpose was to investigate Chios mastic gum (CMG) extract as an potential anti-tumor agent for oral squamous cell carcinoma in vitro. METHODS: We designed a study to examine the effects of CMG extracts on growth of oral squamous cell carcinoma cell line, YD-10B and to determine whether the extracts could induce apoptosis through the activation of caspase-3, using the common chemotherapeutic agent Paclitaxel (Taxol, Bristol-Myers Squibb) as a control. RESULTS: MTT assay suggested that both CMG and Taxol inhibited the proliferation of YD-10B cells in a time and dose dependent manner. Moreover, 10 μg/mL of CMG and 50 μg/mL of Taxol caused fragmentation of the genomic DNA at 24 hour. Finally, 10 μg/mL of CMG and 50 μg/mL of Taxol caused cleavage of procaspase-3 in western blot analysis. CONCLUSIONS: These results suggest CMG's potential as an anti-tumor agent.ope

Osteochondroma of the mandibular inferior border: an atypical case

An osteochondroma is an osseous protuberance with cartilaginous growth potential, usually arising in skeletal bone and relatively uncommon in the craniofacial bone. Osteochondroma of the craniofacial region usually occurs at the condyle or the tip of the coronoid process, and rarely arises in the mandibular body, symphysis, ramus, and similar areas. Excision of the lesion including the periosteum is curative, and recurrence or malignant change (usually to a chondrosarcoma) after treatment is rare. We present an atypical case of osteochondroma in the left mandibular inferior border with review of literatureope