Rainer Schmelzle

Jaw malformations plus displacement and numerical aberrations of teeth in neurofibromatosis type 1: a descriptive analysis of 48 patients based on panoramic radiographs and oral findings

AIM The aim of this study was to analyse jaw malformations and tooth displacement in patients with neurofibromatosis type 1 (NF1). MATERIAL AND METHODS Forty-eight patients were included in the study (male or female 24 each). All fulfilled the current NIH diagnostic criteria for NF1. The age range was 2.5-66 years. The type of neurofibroma was histologically proven in surgically treated patients. Patients with disseminated cutaneous neurofibromata and those with the plexiform type were distinguished. The analysis was based on physical investigation, photographs, panoramic radiographs and dental casts. RESULTS With the emphasis on alterations of tooth position, deformities of the adjacent bones and malocclusion, the majority of these patients (26) were affected by plexiform neurofibromata. In the other 22 patients with disseminated neurofibromata, malformations of the alveolar ridge were absent and individual oral symptoms were rarely found and were mild, and in all cases were unimpaired. Numerical aberrations and retention of molars was exclusively associated with a trigeminal nerve affected by plexiform neurofibroma. Aplasia of a second lower molar was recognized in four of these plexiform-neurofibroma patients. CONCLUSION It is widely accepted that malformations of the facial skeleton are often of genetic origin. However, in this study these malformations were strongly associated with plexiform neurofibromata originating from the trigeminal nerve. Thus, in addition to presently unknown genetic factors, the pattern of skeletal malformation can be caused by tumour invasion and local destruction, e.g. the neuromuscular unit or prenatal development of the plexiform neurofibroma in the inferior alveolar nerve. It is further concluded that epidemiologic studies on the incidence and severity of NF1 in the oral and maxillofacial region have to distinguish between patients with or without plexiform neurofibroma, especially when analysing alterations and deformities of the jaws, teeth and malocclusion. Aplasia of second inferior molars is an additional (dental) finding associated with plexiform neurofibromata in NF1.

Outcome and complications of 540 microvascular free flaps: the Hamburg experience.

The aim of this study was to retrospectively analyze surgical outcome and complications of 540 free flap procedures performed at the Department of Oral and Maxillofacial Surgery of the University Medical Center Hamburg-Eppendorf during 1987–2005. A total of 532 patients were reconstructed with 540 flaps: 32% were latissimus dorsi flaps, 23% were radial forearm flaps, 21% were iliac crest flaps, 10% were fibula flaps, 6% were jejunal flaps, and 8% were other flaps. Thrombosis of one of the vessels and hematoma were the most frequent causes of failure in microvascular free tissue transfer. A total free flap failure occurred in 34 (6.2%) and a partial flap failure in 42 (7.7%) patients. The most reliable flap in regard to survival was the radial forearm flap. The present study confirms that free flaps are extremely reliable in achieving successful reconstruction of the head and neck.

Mucoepidermoid carcinoma of salivary gland origin: classification, clinical-pathological correlation, treatment results and long-term follow-up in 55 patients

Over a period of 30 years, 55 patients with mucoepidermoid carcinomas (MEC) of the salivary glands underwent surgical treatment. Reclassified TNM-stage (Hermanek et al., 1992) at the time of initial diagnosis varied (T0: 0, T1: 26, T2: 20, T3: 2, T4: 7; N0: 49, N1: 4, N2: 2; M0: 53, M1: 2). In 46% (n = 24), the history of symptoms ranged from 6 months to 2 years without any specificity of features. The therapy of choice is a radical ablative surgery of the primary tumour. The resection of the related lymphatic system has to be included in the therapeutic concept in patients suspected of having metastases of the regional lymph nodes. The prognosis is excellent in patients with a localized manifestation of the disease only. Our patients who died for reasons of tumour metastasis had all been classified as stage III or IV at the time initial diagnosis (n = 5). Distant metastases are rarely found even decades after surgical therapy (n = 1). This is why a long-term follow-up is recommended for patients with MEC of the salivary glands.

The biosurgical wound debridement: Experimental investigation of efficiency and practicability

The use of maggot therapy is experiencing a revival in the treatment of problem wounds. Although this alternative therapy is ancient, little scientific research has been aimed at standardizing this therapy. The purpose of our investigation was to determine the debridement efficiency of this therapy, i.e., to compare the use of freely crawling maggots with maggots in a Biobag and to estimate the amount of maggots needed for debridement. We designed an artificial wound model and investigated the rate of decomposition of porcine tissue. Two application alternatives were compared, each being carried out either for 3 or for 4 days, (1) maggots that were allowed to crawl freely over the substrate and (2) maggots confined to a Biobag with no direct contact with the wound. We found that a single maggot was capable of debriding approximately 0.15 g of dead tissue per day. Assuming an absolute difference of <0.05 g per day and maggot as clinically irrelevant, the debridement efficiency of free maggots appears to be similar to those in a Biobag. We were able to determine for the first time the average debriding ability of maggots and thus provide the clinician with data that may help to optimize the maggot therapy by facilitating more exact approximations of the number of maggots needed. Furthermore, the result that the maggots in the Biobag are equal to free maggots in their debriding efficiency will promote its use, especially with respect to the time saved for changing of the dressings. Also, we were able to show that no direct contact is necessary between the maggots and the wound surface, proving that the mechanical crawling effect appears to be neglectable. Because significantly more tissue was metabolized after 4 than after 3 days, application intervals of 4 days appear more appropriate than those of 3 days.

Intraoperative Cone-Beam Computed Tomography in Oral and Maxillofacial Surgery Using a C-Arm Prototype : First Clinical Experiences After Treatment of Zygomaticomaxillary Complex Fractures

PURPOSE To describe the first clinical applications of intraoperative cone-beam computed tomography with an integrated flat-panel detector in oral and maxillofacial surgery after surgical treatment of zygomaticomaxillary complex fractures PATIENTS AND METHODS Nine cone-beam computed tomography datasets of patients with zygomaticomaxillary complex fractures were intraoperatively acquired using a mobile isocentric C-arm (PowerMobil; Siemens Medical Solutions, Erlangen, Germany), including a flat-panel detector. Datasets based on 400, 200, and 100 fluoroscopic images were performed with different tube currents (4.6 mA, 3.3 mA, 2.3 mA, 1.2 mA, and 0.5 mA) and a current tube voltage of 100 kV. Postprocessing resulted in 15 different datasets available for comparison with corresponding preoperative computed tomography datasets. Four oral and maxillofacial surgeons and 2 experienced radiologists evaluated each dataset regarding noise, transition, and the delimitation of landmarks. RESULTS All examinations were successfully performed. Reconstructed datasets showed high-resolution images of all midfacial osseous structures in near-computed tomography quality. Regarding high-contrast structures, detailed analyses of datasets acquired in this study suggest that the parameters 400 projections, 1.2 mA, and 100 kV are sufficient. In terms of soft-tissue visualization, a higher level of mA seems preferable. CONCLUSIONS The tested prototype predicts a new era in cone-beam computed tomography imaging. The integration of a flat-panel detector will overcome the limitations of current available systems. The size of the field of view is increased allowing regularly the visualization of the whole facial skeleton. Particularly in cases of open reduction of unilateral fractures, the assessment of symmetry is of clinical value.

Resection of small plexiform neurofibromas in neurofibromatosis type 1 children

BackgroundPlexiform neurofibromas (PNF) are benign tumors of the peripheral nerve which mostly develop in patients with neurofibromatosis type 1 (NF1). Surgical interventions are usually not applied to children with small tumors. These are rather restricted to debulking of larger tumors in adults that cause clinical complications or aesthetic disfigurement. In most cases, a total resection of PNF is not possible due to the network-like growth of the tumors.Patients and methodsEarly surgical intervention was carried out for 9 small PNFs in 7 NF1 children. Tumor resection was performed following the graphical delineation of the affected skin and according the MRI findings.ResultsTotal resection was achieved for all 9 PNF without causing any neurological or organic deficit. Annual magnetic resonance tomography over a period of four years did not reveal any relapse of the tumors.ConclusionsEarly surgical intervention for small superficial PNFs in NF1 children have various advantages and may especially be considered a strategy to prevent progression.

Clinical follow-up examination of surgically treated fractures of the condylar process using the transparotid approach.

PURPOSE The surgical approaches for the open treatment of condylar process fractures have been controversial. In our study, we evaluated the morbidity of the transparotid approach during 2 years of follow-up. PATIENTS AND METHODS A total of 48 patients with condylar process Class II and IV fractures according to classification of Spiessl and Schroll, were included in the present study. Of the 48 patients, 16 were female and 32 male. The patient age range was 16 to 79 years (average 36.52). All patients were treated using the transparotid approach, with rigid internal fixation using miniplates. Follow-up examinations were performed for a minimum of 6.5 months and a maximum of 25 months (average 12.16) after surgical treatment. At the follow-up examination, the patients completed the Mandibular Function Impairment Questionnaire, and the examiner completed the Helkimo index. X-rays taken before, directly after, and 6 months after surgery were compared. RESULTS None of our patients had problems with wound healing; 2 patients developed a fistula of the parotid gland; and 4 patients developed palsy of the facial nerve that was completely reversible after 6 weeks. The results of the Mandibular Function Impairment Questionnaire and the Helkimo index revealed only a few subjective and objective problems after 6 months. CONCLUSIONS The transparotid approach to condylar process fractures is most appropriate for strongly displaced Class II fractures. Especially for very old patients with dementia, for whom maxillomandibular fixation is contraindicated, this approach is very appropriate. Another benefit to this type of patient is the short operating time, with an average of 45 minutes.

Major Mandibular Surgical Procedures as an Indication for Intraoperative Imaging

PURPOSE This study investigated 3-dimensional (3D) imaging with intraoperative cone beam computed tomography (CBCT) in major mandibular reconstruction procedures. PATIENTS AND METHODS The study group was comprised of 125 patients (83 males, 42 females) admitted for surgical treatment of the mandible. The patients ranged in age from 3 months to 91 years (average age, 40.72 +/- 22.843 years). Surgical procedures of the mandible were subdivided into repair of body fractures (17 patients), angle fractures (21 patients), condylar fractures (14 patients), and multiple fractures (30 patient). In addition, the study group included 21 patients undergoing orthognatic surgery and 22 undergoing reconstructive surgery on the mandible. Intraoperatively, 3D images were generated with a mobile CBCT scanner (Arcadis Orbic 3D; Siemens Medical Solutions, Erlangen, Germany). RESULTS During open reduction of mandibular fractures, not all fracture sites can be readily exposed for direct visual control. For example, the lingual cortical bone of the mandible is difficult to assess intraoperatively. This structure and others can be effectively visualized using the 3D mode of CBCT. Furthermore, screw placement can be evaluated, specifically in insertions near the alveolar nerve. The intraoperative acquisition of the data sets is uncomplicated, and the image quality is sufficient to allow evaluation of the postoperative result in all cases. CONCLUSION Intraoperative CBCT has proven to be a reliable imaging technique for providing visual control during major mandibular procedures.

Intraoral osteotomies using piezosurgery for distraction in an infant with Pierre–Robin sequence

Airway management in infants with Pierre Robin sequence (PRS) is often challenging. Advancement of the tongue base using mandibular distraction in neonates can avoid tracheotomy and is increasingly propagated. The osteotomies can be performed via intra- and extraoral approaches. Nowadays, for precise bone cutting, piezosurgical devices have been introduced in maxillofacial surgery, which we used for osteotomies via the intraoral approach in the 7-week-old patient presented in this study. Instead of a preoperative CT scan, a 3D data set was generated preoperatively in the operating theatre using a 3D C-arm system. After bilateral transcutaneous pin placement and osteotomies, a second 3D data set was acquired. Primary and secondary reconstructions clearly visualized the patient’s bone despite the low level of ossification in newborns and the presence of a large amount of metal implants. In view of the low level of radiation exposure going along with the 3D C-arm imaging, a follow-up examination after removal of the distractors was performed. With this report of a 7-week-old female infant with the diagnosis of PRS, we want to extend the surgical and diagnostic armamentarium for the treatment of infants with PRS.

Leech Therapy in Reconstructive Maxillofacial Surgery

PURPOSE Corrective plastic surgery is indicated after accidents, burns, cancer surgery, or postoperative wound healing disorders with large tissue defects. The range of reconstructive techniques includes local skin flaps, pedicle grafts, and microvascular anastomosed flaps in the case of large defects. Main complications such as arterial and venous insufficiency caused by a vessel collapse or a vascular spasm are reported regularly in the area of anastomosed vessels and are the concern of any surgeon. Today, leeches are used if wound healing is at risk because of hemodynamic imbalance or a venous insufficiency. PATIENTS AND METHODS A retrospective evaluation of 148 patients who underwent medical leech therapy in the case of local or pedicaled flaps and some patients who had undergone reconstruction with microvascular flaps from 2005 and 2010 was conducted. Our sample had the typical symptoms of venous congestions of their flaps, despite suture removal, relief of pressure on the flap, and the elimination of a hematoma beyond the flap after surgery. Medical leech therapy was used in these cases. RESULTS Our series has confirmed the excellent and predictable healing after medical leech therapy for local and microsurgical anastomosed flaps in the case of venous congestion. CONCLUSION Leech therapy should be considered as a reliable additional procedure and an advantage in maxillofacial and plastic reconstructive surgery to remedy complications resulting from a hemodynamic imbalance or venous insufficiency in the immediate postoperative period.