Polymorphous Low-Grade Adenocarcinoma: A Proposed Reconstruction Protocol Based on Past Surgical Experience.

BACKGROUND: To propose a reconstructive protocol based on surgical management experience of polymorphous low-grade adenocarcinoma (PLGA) and the location of the primary lesion. METHODS: Data on the surgical management and the reconstructive technique of 14 histologically conformed patients with PLGA, all treated by the same surgeon, were analyzed and evaluated. RESULTS: Mean follow-up period in our series was 6.2 years. Mean age at diagnosis was 55.5 years and female to male ratio was 2.2:1. The most common presenting sign was a nonpainful lump or mass in an intraoral location. Most patients were managed by wide local excision and reconstruction method varied from primary closure to the use of radial forearm graft. Recurrence appeared in one of the patients in this series, while 2 required further radiation therapy. A protocol for reconstruction of intraoral patients with PLGA is suggested based on our analysis. CONCLUSION: Surgical management is the gold standard for PLGA treatment. Neck dissection is recommended only in patients with presurgery fine-needle aspiration confirmed lymph node involvement. The reconstruction depends mainly on location and size of the primary lesion.

Functional Reconstruction in Mandibular Avulsion Injuries.

The present report describes the planning and surgery as well as pitfalls and management of a patient with a near total mandibular avulsion injury that was rehabilitated using three-dimensional (3D) laser printing of a titanium lower jaw. Laser-sintering involves zapping layers of powdered metal to recreate a 3D implantable skeletal defect. The process involves using either mirror imaging of the unaffected side or using archival image database of healthy individuals. A 25-year-old man presented with a gunshot injury that left him with a near total avulsed mandible. The patient received state-of-the-art treatment using a laser 3D printed mandible which was connected to the muscles of mastication for functionality. The inner side of the titanium jaw was filled with the patient's comminuted fractured bones in addition to harvested iliac crest bone graft that was covered with the patient's remaining periosteal tissue. The implantation of a near total mandible using 3D laser printing is a fast and predictable process that in selected patients can result in aesthetically as well as functionally excellent results. The authors believe that the future of craniofacial reconstruction will employ these methods for facial bony reconstruction.

Lymphoepithelial carcinoma--review of the treatment modalities and report of a rare case in the sublingual gland.

Controversies exist in the current literature regarding the treatment of lymphoepithelial carcinoma (LEC). The presented study summaries the literature controversies in the treatment of LEC and present a case of a rare LEC diagnosed in the sublingual gland of an otherwise healthy 21-year-old Arab woman. The patient was admitted for swelling in the sublingual area. A biopsy indicated a diagnosis of LEC of the sublingual gland. Treatment included a wide resection with safe margins, marginal mandibulectomy, functional neck dissection, and a radial forearm free flap for reconstruction. The patient received concomitant radiotherapy and has remained disease free since her last follow-up. The recommended primary treatment, based on the literature review, is primary surgical excision with neck dissection and optional adjuvant radiotherapy to the gland area. Chemotherapy was not found to be beneficial according to the literature.

Does long-term treatment with Doxil® predispose patients to oral cancer?

We present a possible adverse reaction related to long-term use of Doxil(®) in female patients. We believe that long-term use of Doxil(®) may predispose female patients to oral squamous cell carcinoma. The patients in this report were not exposed to the common risk factors related to oral cancer formation such as smoking or alcohol consumption. Both patients were 59-year-old females. The first patient was diagnosed in 2001 with stage IIIC ovarian cancer. Seven years following treatment with Doxil(®), she was diagnosed with stage III squamous cell carcinoma of the right maxilla. The second patient was diagnosed with Kaposi's sarcoma with evidence of spread to the lungs. Four years following treatment with Doxil(®) she was diagnosed with stage I squamous cell carcinoma of the left maxilla. A literature review did not reveal any report on Doxil(®) and predisposition to oral cancer; however, we found an abstract that was presented at the last annual meeting of the American Society of Clinical Oncology (ASCO) by Cannon et al. When we combine the data from Cannon et al. and the data presented here, a total of six female patients developed an epithelial carcinoma of the oral cavity following long-term treatment with Doxil(®). We believe that a large-scale study should be initiated on patients that were treated with Doxil(®) for more than 3 years, since these patients might be at risk for developing secondary cancer of the oral cavity.

Incidence of oral cancer occult metastasis and survival of T1-T2N0 oral cancer patients.

PURPOSE: In head and neck cancer, the most important prognostic factor is the presence or absence of neck metastasis. Although still debated in the published data regarding the "wait and see" policy for Stage T1-T2 oral cancer, a large number of clinicians support the necessity of neck dissection, especially in cases of oral tongue carcinoma, because of the poor prognosis and high risk of recurrence. The aim of the present study was to summarize and quantify the incidence of occult metastasis in oral cancer treatment at the oral and maxillofacial surgery department, Rambam Medical Center, in the past 10 years. PATIENTS AND METHODS: A total of 142 neck dissections performed at our department in the past 10 years (1998 to 2009) and a series of 68 patients (44 men and 22 women) treated for Stage T1N0 or T2N0 oral cancer were included in the present retrospective study. All patients underwent surgical resection of the oral cancer and selective neck dissection of the ipsilateral side. RESULTS: Occult lymph node metastases were detected in 11 patients (16% overall, 9 in the tongue, 1 in the buccal mucosa, and 1 in the gingiva of the mandible). The frequency of occult metastasis from tongue carcinoma was 34% (9 of 26 cases). The 5-year survival rate in the present study was 78.9%. In patients who underwent chemotherapy, radiotherapy, brachytherapy, or a combination of the 3 after surgical management, the overall survival rate decreased significantly to 22.5% (P = .006, log-rank test). CONCLUSION: The incidence of occult metastasis in patients with oral cancer in the present study was 16% overall. In those with tongue carcinoma, a much greater incidence (34%) of occult metastasis was detected. Furthermore, the need for chemoradiotherapy after initial surgical management, mainly because of occult metastasis, was a significant negative predictor of patient outcome. The results of the present study emphasize the need for prophylactic neck dissection in patients with oral cancer diagnosed with Stage T1N0 or T2N0 disease, especially when the primary lesion is localized in the tongue.

Surgical approach to impacted mandibular third molars--operative classification.

PURPOSE: The aim of the present study is to suggest a convenient way to classify the position of the impacted third mandibular molar relative to the mandibular canal and to suggest indications for the use of each surgical approach for mandibular third molar extraction. MATERIALS AND METHODS: The presented new typing system, Third Molar Classification (TMC), is a simple and easy-to-apply method for the surgical management of mandibular third molars and can be extended for any ectopic or impacted mandibular tooth. There are 3 major types of third molar positions. The second type is subdivided further into 2 subtypes. In the present study, 9 patients with high-risk mandibular third molars were treated according to the present classification and are presented and discussed. Patients typed as TMC IIb were treated with a sagittal split osteotomy approach and patients typed as TMC III were treated with an extraoral approach. RESULTS: The operative classification was successfully implemented in very rare cases of deeply impacted mandibular third molars. In 3 of 9 cases (33%) minor complications included some degree of hypoesthesia using the extraoral approach; these complications resolved spontaneously without the need for any intervention. CONCLUSIONS: The present study describes the use of a new surgical classification system for treatment planning in all types of mandibular third molar extractions. We believe that the present classification could help the oral and maxillofacial surgeon in decision-making and limit the possible risks that are present when attempting to extract impacted mandibular third molars.

The use of the temporalis myofascial flap in oral cancer patients.

PURPOSE: The purpose of this article is to present our experience using the simple, reliable, and predictable temporalis myofascial flap (TMF) in rehabilitation and reconstructive surgery in cancer patients who are older and whose health is compromised in a way that precludes the use of microvascular free flaps. PATIENTS AND METHODS: Our series includes 10 patients (8 men and 2 women), ranging in age from 62 to 85 years (mean, 73.4 years). A full-thickness anteroinferiorly based TMF was used in 5 patients for palatal reconstruction, 3 patients for buccal lining reconstruction, and 2 patients for reconstruction after resection of facial skin and buccal mucosa. RESULTS: The TMF survival rate in this study was excellent, with an 80% success rate (2 minor complications). Complications included 1 case of a partial distally necrotic flap that resolved after local debridement and did not require further flap manipulation and 1 case of transient, spontaneously resolved facial nerve (temporal branch) palsy and limited mouth opening (<20 mm), which also resolved after judicious physiotherapy. CONCLUSIONS: The TMF was found in this study to have a fairly low complication rate, was relatively easy to use, and had a predictable outcome. The proximity and reliability of the myofascial flap make it a favorable and highly recommended candidate for oral and maxillofacial reconstructive surgery in elderly patients, who usually have relatively poor recovery potential and decreased physiologic reserves.

Regeneration of bone and periodontal ligament induced by recombinant amelogenin after periodontitis.

Regeneration of mineralized tissues affected by chronic diseases comprises a major scientific and clinical challenge. Periodontitis, one such prevalent disease, involves destruction of the tooth-supporting tissues, alveolar bone, periodontal-ligament and cementum, often leading to tooth loss. In 1997, it became clear that, in addition to their function in enamel formation, the hydrophobic ectodermal enamel matrix proteins (EMPs) play a role in the regeneration of these periodontal tissues. The epithelial EMPs are a heterogeneous mixture of polypeptides encoded by several genes. It was not clear, however, which of these many EMPs induces the regeneration and what mechanisms are involved. Here we show that a single recombinant human amelogenin protein (rHAM(+)), induced in vivo regeneration of all tooth-supporting tissues after creation of experimental periodontitis in a dog model. To further understand the regeneration process, amelogenin expression was detected in normal and regenerating cells of the alveolar bone (osteocytes, osteoblasts and osteoclasts), periodontal ligament, cementum and in bone marrow stromal cells. Amelogenin expression was highest in areas of high bone turnover and activity. Further studies showed that during the first 2 weeks after application, rHAM(+) induced, directly or indirectly, significant recruitment of mesenchymal progenitor cells, which later differentiated to form the regenerated periodontal tissues. The ability of a single protein to bring about regeneration of all periodontal tissues, in the correct spatio-temporal order, through recruitment of mesenchymal progenitor cells, could pave the way for development of new therapeutic devices for treatment of periodontal, bone and ligament diseases based on rHAM(+).

Odontogenic myxoma--a case series and review of the surgical management.

BACKGROUND: Odontogenic myxomas (OMs) are considered to be a benign odontogenic tumour with locally aggressive behaviour. Since these neoplasms are rare in the oral cavity, the possible surgical management can be quite variable. Literature recommendation can vary from simple curettage and peripheral ostectomy up to segmental resection. CASE REPORTS: In the present article, a series of three new cases are presented and discussed. The first case is a 43-year-old male presented with a relatively large OM in the left maxillary area. The second case is a 37-year-old female presented with a relatively smaller left maxillary swelling that was diagnosed as OM. The third and final case is a 52-year-old male presented with a large OM of the right mandibular molar area. The surgical management that was chosen in each case is discussed. CONCLUSION: In the present manuscript, a short review of the current literature on the surgical management of OMs is presented with a review of three cases of oral OMs that were treated in our department, followed by a discussion of the treatment options in each case.

High yield of biologically active recombinant human amelogenin using the baculovirus expression system.

The amelogenins are secreted by the ameloblast cells of developing teeth; they constitute about 90% of the enamel matrix proteins and play an important role in enamel biomineralization. Recent evidence suggests that amelogenin may also be involved in the regeneration of the periodontal tissues and that different isoforms may have cell-signalling effects. During enamel development and mineralization, the amelogenins are lost from the tissue due to sequential degradation by specific proteases, making isolation of substantial purified quantities of full-length amelogenin challenging. The aim of the present study was to express and characterize a recombinant human amelogenin protein in the eukaryotic baculovirus system in quantities sufficient for structural and functional studies. Human cDNA coding for a 175 amino acid amelogenin protein was subcloned into the pFastBac HTb vector (Invitrogen), this system adds a hexa-histidine tag and an rTEV protease cleavage site to the amino terminus of the expressed protein, enabling effective one-step purification by Ni2+-NTA affinity chromatography. The recombinant protein was expressed in Spodoptera frugiperda (Sf9) insect cells and the yield of purified his-tagged human amelogenin (rHAM+) was up to 10 mg/L culture. Recombinant human amelogenin (rHAM+) was characterized by SDS-PAGE, Western blot, ESI-TOF spectrometry, peptide mapping, and MS/MS sequencing. Production of significant amounts of pure, full-length amelogenin opened up the possibility to investigate novel functions of amelogenin. Our recent in vivo regeneration studies reveal that the rHAM+ alone could bring about regeneration of the periodontal tissues; cementum, periodontal ligament, and bone.