Ralf Schoen

Inferior Alveolar Nerve Transposition—An In Vitro Comparison Between Piezosurgery and Conventional Bur Use

An in vitro comparison between a new ultrasound-based piezoelectric device and a conventional bur was performed for lateralization or transposition of the inferior alveolar nerve to evaluate the effects on soft and hard tissue. Transposition of the inferior alveolar nerve was performed in the cadaver mandibles of 10 sheep: the left nerve was uncovered with a saline-cooled diamond-coated spherical bur (2000 rpm), and the right nerve was uncovered with the piezoelectric device mounted with a spherical diamond tip. The surface, the zone of bone defect, and the nerve were examined by light microscopy and laser microscopy. Bone treated with the rotary bur showed significantly smoother surfaces and shallower defect zones (50 microm) in comparison with the piezoelectric device (150 microm). Lesions of the epineurium and an increased amount of bone particles were found in the lesions prepared with the piezoelectric device. In vitro preparation with the piezoelectric device was more invasive to the bone than was a conventional diamond bur. Touching the inferior alveolar nerve resulted in roughening of the epineurium without affecting deeper structures. The degree of injury was lower than when using the conventional rotary bur.

Endoscopic approach to removal of an ectopic mandibular third molar

M. M. Suarez-Cunqueiro, ∗, † R. Schoen, ‡ A. Schramm, ‡ N.-C. Gellrich, § R. Schmelzeisen ¶ ∗Research Fellow, Department of Oral and Craniomaxillofacial Surgery, University Hospital Freiburg, Albert-Ludwigs-University, Freiburg, Germany; †Assistant Professor, University Santiago de Compostela, Spain; ‡Senior Resident; §Professor; ¶Professor and Chairman, Department of Oral and Craniomaxillofacial Surgery, University Hospital Freiburg, Albert-Ludwigs-University, Freiburg, Germany

Speech and Swallowing Impairment After Treatment for Oral and Oropharyngeal Cancer

OBJECTIVES To assess the prevalence of speech and swallowing impairment after radical surgery for oral and oropharyngeal cancer from the patients viewpoint and to examine the association of these functional alterations with selected clinical characteristics regarding patients, tumors, and oncologic treatment. DESIGN Cross-sectional, multicenter study using a self-administered questionnaire. SETTING Forty-three hospitals in Germany, Switzerland, and Austria. PATIENTS A total of 3894 questionnaires about rehabilitation problems after treatment for oral and oropharyngeal squamous cell carcinoma were sent to patients. Of these, 1652 were filled out and returned, and 1334 (80.8%) met the inclusion criteria. MAIN OUTCOME MEASURES Morbidity associated with treatment of oral and oropharyngeal cancer. RESULTS Speech problems were reported by 851 patients (63.8%), and swallowing problems were reported by 1006 patients (75.4%). The variables that presented a significant association with speech and swallowing impairment were sex, tumor location, pTNM stages, stage of tumor, treatment modality, and reconstruction type. CONCLUSIONS This survey, based on patient perception, suggests that those who undergo radiotherapy associated with the surgical removal of a tumor, have late-stage tumors (III-IV), or have tumors located in the floor of the mouth should be informed of the greater risk of persistent severe speech and swallowing problems.

Endoscopic Approach to Removal of an Osteochondroma of the Mandibular Condyle

Osteochondroma is one of the most common benign tumors of bone. It usually develops in long bones but rarely occurs in the oral and maxillofacial area, where it is generally associated with the coronoid process followed by the condyle. An osteochondroma protrudes from the surface of a bone and is a bony excrescence covered with cartilage. It may arise spontaneously or as a result of previous osseous trauma. An osteochondroma can affect any bone preformed in cartilage. Malignant transformation should be suspected if an exostosis rapidly increases in size, especially in an adult, such as in a chondrosarcomatous transformation. On panoramic radiographs, an osteochondroma of the condylar process is noted consistently as a radiopaque condylar enlargement with a tapered anteromedial extension into the lateral pterygoid tendon. In this region, it is too deeply located to be examined clinically. Osteochondroma of the condylar process shows a slowly progressive limitation of the range of motion of the jaw, facial asymmetry, malocclusion, and deviation on opening.

Increased Safety in Computer-Assisted Skull Base Surgery by Navigation-Guided Transmandibular Approach

Introduction: Computer-assisted surgery (CAS) is very helpful in the preoperative planning of surgical procedures of both soft- and hard-tissue tumors, treatment of fractures, and even in the insertion of dental implants. Intraoperative important anatomical landmarks can be identified more easily. In cases of the resection of soft-tissue tumors after chemotherapy or radiation, the old margins of the tumor can be found more easily by using the CAS and resection of the tumor is safer. Method: We present a case of a child at age 9 years who presented with increased mouth opening and swelling of the right cheek. MRI revealed a tumor in the right pterygopalatinal fossa affecting the skull base and the mandible. The biopsy showed an embryonal rhabdomyosarcoma. Result: After performing MRI and CT scans, image fusion was done for planning of the surgical procedure. The tumor and safety margins were marked. Prior to surgery, chemotherapy was performed for decreasing the tumors size. For the surgical procedure a transmandibular approach was chosen. Intraoperatively, the tumor was resected within the planned safety margins using CAS. Histologically, the tumor was resected in clean margins. Postoperatively, a radiation therapy was conducted. After 3 years, the child is still free of recurrence of the tumor. Conclusion: Using computer-assisted surgery in planning a surgical procedure, especially in soft- and hard-tissue tumors, is very helpful. Intraoperative computer-assisted surgery increases the safety of the resection of a tumor in the old margins, especially if presurgical treatment using chemotherapy and/or radiation was performed. For the treatment of an embryonal rhabdomyosarcoma, an interdisciplinary approach should be performed.