[Titanium magnets on implants as an aid in rehabilitation after tumor treatment]. / Titanmagnete auf Implantaten als Hilfsmittel zur Rehabilitation nach Tumorbehandlung.

After the resection of a tumor, many patients need a reconstruction with hard and soft tissue and also with sufficient dentures. Often, only little space is available for the implantation. Implant length and diameter have to be reduced, and the result is a change in the biomechanics with a possible mechanical overloading of the implant. We examined 52 tumor patients undergoing reconstruction with 189 implants. A new concept involving attachment with the help of magnets is presented, offering a satisfactory solution in these difficult cases after tumor resection and reconstruction.

[A new aspect on the development of chronic middle ear diseases in patients with cleft palate]. / Ein neuer Aspekt zur Entstehung chronischer Mittelohrerkrankungen bei Patienten mit Gaumenspalte.

BACKGROUND: The prevalence of chronic middle ear disease in patients after surgery for cleft palate is about 50%. Aim of the present study was to analyse its morphological and physiological causes to prevent chronic atelectatic otitis media or cholesteatoma. METHODS: 15 adult patients with cleft palate were examined using middle ear microscopy, pure tone audiometry, EMG of the tensor veli palatini muscle and MRI of the Eustachian tube. RESULTS: 8 of 15 patients had chronic middle ear disease. With 13 of 15 patients single motor unit action potentials could be recorded from the tensor veli palatini muscle. MRI of the Eustachian tube revealed two decisive observations in patients with chronic middle ear disease: in 4 patients the pterygoid hamulus could not be detected, in all otitis patients the continuity of tensor veli palatini muscle was interrupted or disturbed by medial or lateral fixation. CONCLUSION: Chronic middle ear disease with cleft palate patients is basically caused by impaired muscular compliance of the Eustachian tube. Thus integrity of hamulus as well as tensor veli palatini muscle must become of crucial interest in cleft palate surgery.

[Primary solitary malignant schwannoma of the trigeminal nerve, Report of a case and review of the literature]. / Primär solitäres malignes Schwannom des N. trigeminus. Fallbericht mit Literaturübersicht.

We present the case of a primary solitary malignant schwannoma of the trigeminal nerve. A total of 55 cases have been described in the literature; however, in these cases two tumors were affecting the supraorbital branch. This nerve-sheath tumor usually affects men in the fifth decade of life. The main clinical sign of malignant schwannomas of the head and neck is an indolent swelling. Hematogenic or lymphogenic metastasis has not been described. Because of the pleomorphism of the tumor cells immunohistochemical study is important. The treatment of choice is radical resection, possibly with adjuvant radio- or chemotherapy. The 5-year survival rate of malignant schwannoma of the trigeminal nerve is 41.7%.

[Ultrasound of segment distraction and callus formation in reconstruction of the mandible. Value of surgical ultrasound of callus distraction of vascularized ilial crest transplants and mandibular segments in a previously irradiated area]. / Sonographie der Segmentdistraktion und Kallusbildung des rekonstruierten Unterkiefers. Stellenwert der chirurgischen Sonographie der Kallusdistraktion vaskularisierter Beckenkammtransplantate und Underkiefersegmente in einer perkutan strahlenvorbelasteten Region.

PURPOSE: B-scan ultrasonography (US) was applied in patients subjected to callus distraction for bone formation at the interface of mandibular segments and vascularised bone grafts. METHODS: This study consisted of 7 patients requiring further surgical augmentation to allow for prosthetic treatment. All patients had been preoperatively irradiated percutaneously in the region of the primary oral squamous cell carcinoma up to an isodose of 60-75.5 Gy. Ablative surgery was then performed, including discontinuity resection of the mandible. Vascularised iliac crest grafts had been chosen due to poor healing conditions in the irradiated recipient site. For callus distraction, a distraction device was inserted in both the mandibular segment and the bone graft. Subsequently, osteotomy was performed, and distracting forces were applied to the segments. For US, a small-part applicator was used (7.5 MHz). RESULTS: US gives a true estimation of the distraction length, actually achieved at the time of investigation. The applicator can be easily adjusted to the area of interest. Application is safe and easy, the results are reliable, and the procedure can be carried out without affecting the hygiene of the wound after surgical intervention. In addition, US enables the supervising surgeon to detect zones of calcification in the area of callus distraction at an earlier point than can be detected by standard x-ray documentation, thus facilitating control of the therapy. CONCLUSION: US is highly recommended for routine application in callus distraction of the mandible. X-ray documentation is a "must".

[Insertion of autografts after acute damage of the common carotid artery. Experimental microvascular anastomoses after balloon dilatation]. / Einsatz von Autointerponaten nach akuter Schädigung der Arteria carotis communis. Experimentelle mikrovaskuläre Anastomosen nach Ballondilatation.

The objective of our investigation was to study the patency rates of anastomoses in arteries, damaged by a balloon dilatation, in a training model of microvascular surgery. In general anaesthesia, a balloon dilatation was repeated 5 times in 31 left common carotid arteries of female Wistar rats (body weight: 250 to 350 g). A common carotid artery autograft of 4 mm was harvested 1 minute after reflow, turned 180 degrees, and reinserted into the artery. The reflow of the vessels was investigated by micro-Doppler ultrasound equipment. Autografts without balloon dilatation or any other intended damage were performed in further 26 common carotid arteries. In addition, in further 14 common carotid arteries the balloon dilatation was the sole damage. The vessels were harvested and investigated postoperatively after perfusion with 3% glutaraldehyde at 1 day, 7 days, and 1 month. The balloon dilatation in no instance caused an occlusion of the vessel as judged by the micro-Doppler ultrasound. One vessel was found to be occluded after reflow was allowed following insertion of the autograft in the group without balloon dilatation. However, this vessel proved to be patent after explantation (patency rate: 100%). In the group with balloon dilatation preceding the autograft insertion, by micro-Doppler ultrasound, 16 vessels were occluded and 14 were patent. At different times of follow-up, in this group the summarized patency rates were 50%. The patency differences in both groups with autografts proved to be significant, both after micro-Doppler imaging and by histological evaluation (p < 0.001). For clinical use the balloon dilatation is recommended to remove a thrombus or to dilate a spastic vessel segment in anastomized vessels threatening the success of microvascular flaps. In this training model of microvascular surgery we demonstrated the thrombogenic effect of balloon dilatation.

Mucoepidermoid carcinoma of the salivary glands, Clinical data and follow-up of 52 cases.

Between 1965 and 1993, a total of 52 patients with mucoepidermoid carcinomas underwent surgical treatment. Their TNM stage at the time of initial diagnosis varied (T0:0, T1:24, T2: 19, T3: 2, T4: 7; NO: 46, N1: 4,N2: 2; MO:50, M1: 2). In the majority of patients (n=24) the history of symptoms ranged from more that 0.5 to 2 years without any specificity of features. Radical ablative surgery of the primary tumour is the therapy of choice. In patients suspected of having metastases of the regional lymph nodes, resection of the related lymphatic system has to be included in the therapeutic approach. The prognosis is excellent in patients with a localized manifestation. The patients who died for reasons of tumour metastasis had all been classified as having stage Iii to IV disease at the time of initial diagnosis. Distant metastases are rarely found even decades after surgical therapy. Long-term follow- up is recommended for patients with mucoepidermoid carcinomas.

Interstitial high-dose rate brachytherapy with iridium-192 in patients with oral squamous cell carcinoma.

Thirty-four patients with recurrent oral and oropharyngeal carcinomas were treated over a period of 4 years, by interstitial high-dose rate (HDR) brachytherapy (BT) using an iridium-192 source (Gammamed 2i and 12i equipment, Sauerwein, Germany) and fractionated application (1 up to 3 times, weekly recovery phases, single maximum dose 10 Gy). Pretreatment characteristics of patients in terms of irradiation (RT) and surgery differed (22 had external RT alone, with a total dose between 60.0 and 75.6 Gy; RT and surgery: 7; surgery alone: 1). The initial TNM-stages (UICC, Hermanek et al., 1987) of patients were: I = 2, II =3, III = 7, IV = 22. In the majority of cases, clinical indications for HDR-BT included tumour recurrence or progression following external RT, and second primary tumours of the oral cavity. Therapy was successful in most cases, i.e. complete remission: 11, partial remission: 16, no change: 2, progression: 5. Local control and overall survival rates, including patients surgically treated after BT, were at 6 months 58% and 62%, and 44% and 53% at 12 months, respectively. This type of treatment is recommended in patients with local recurrence or second primary tumours after previous external RT in the head and neck region. However, the benefit of interstitial HDR-BT remains questionable, particularly in patients with large tumours and lymph node metastases.

[Wound management after wisdom tooth osteotomy]. / Wundversorgung nach Weisheitszahnosteotomie.

Closure and dressing techniques in wound treatment after surgical removal of the mandibular third molars were compared. Large abscesses were found after third molar removal in 8 percent. An extraoral incision was made in 58 percent of these cases. On the other side, in a group of 1189 third molar removals treated by a gauze strip no abscess was observed. In a further investigation the subjective disturbance of patients treated with a dressed gauze were the slightest. Also, the dressing technique in the treatment after third molar removal could decrease the number of postoperative infections.

[Merkel cell carcinoma of the face. Histology, clinical course and therapy in six cases]. / Das Merkelzellkarzinom im Gesichtsbereich. Histologie, klinischer Verlauf und Therapie bei 6 Fällen.

Six patients suffering from Merkel cell carcinoma of the face are described. A reliable confirmation and differential diagnosis of Merkel cell carcinoma have become possible with the aid of immunohistochemistry. There is a poor prognosis for patients affected by this tumour. Three out of the six cases described died within two years, two of them with distant metastases, one with a widespread local recurrence. Optimal treatment of Merkel cell carcinoma consists in early radical resection, perhaps combined with radiotherapy.

[Microvascular anastomoses in irradiated blood vessels in the area of the mouth, jaw and face]. / Mikrovaskuläre Anastomosen an bestrahlten Gefässen im Mund-, Kiefer- und Gesichtsbereich.

Pedicle and free microsurgical reanastomized vascularised flaps are useful to cover defects in an irradiated area. In 51 patients microvascular anastomoses were performed on irradiated vessels in the neck area. Facial reconstruction was done after radiation by free flaps. Seventeen jejunum, 10 myocutaneous, 21 iliac crest and 3 fibula flaps were transplanted. The time between irradiation and reconstruction varied between 2 and 144 months. Four anastomoses had to be revised, two flaps were totally lost. Although the vessels were damaged by preoperative radiotherapy, 92 percent of the anastomoses were patent. This success rate is as high as in anastomoses on non-irradiated vessels.

[Diagnosis and differential diagnosis of sialo-odontogenic (glandular-odontogenic) cyst]. / Diagnose und Differentialdiagnose der sialoodontogenen (glandulär-odontogenen) Zyste.

Sialo-odontogenic (glandular-odontogenic) cyst is a new entity in the classification of developmental epithelial odontogenic cysts. Differentiation of this type of odontogenic cysts from dentigerous cysts and keratocysts and also from cystic mucoepidermoid carcinoma is essential. A sialo-odontogenic (glandular-odontogenic) cyst is likely to show aggressive growth, so that complete resection is essential. We demonstrate sialo-odontogenic (glandular-odontogenic) cyst by presenting four new cases and differentiate it from a special type of odontogenic keratocyst and a typical cystic mucoepidermoid carcinoma.

Blunt trauma lesions of the extracranial internal carotid artery in patients with head injury.

Blunt trauma lesions of the extracranial internal carotid artery (ICA) are rare. In our hospital 18 patients with such an injury were diagnosed. All patients were involved in traffic accidents. Most of them had sustained head injuries with fractures of the skull, mandible or maxilla. The onset of neurological signs, most frequently hemiparesis, was usually delayed. 50 percent had bilateral ICA lesions but the clinical presentation was similar to those with unilateral lesions. Mortality of patients with ICA lesions was substantial (28%).

Laser Doppler monitoring of free microvascular flaps in maxillofacial surgery.

In free microvascular flap transplantation, reliable postoperative monitoring is necessary to indicate the necessity for early re-exploration in the event of decreased blood supply. In this study the positive evidence of laser Doppler monitoring of free flaps was investigated in 28 cases. Myocutaneous, osteomyocutaneous and small intestine flaps were measured. The laser Doppler flowmetry values ranged within a wide band and were relative to the different tissues measured, and the patients. It was not possible to define a reliable inferior limit for the various tissues. Only the assessment of the development of the values was interesting. Flaps with high measured laser Doppler flowmetry values were successful, flaps with decreasing values showed problems. The most important tool for the surgeon is his clinical experience, but laser Doppler monitoring in flap transplantation can be helpful to the surgeon.

[Injury of the inferior alveolar nerve due to Carnoy's solution]. / Schädigung des N. alveolaris inferior durch die Carnoysche Lösung.

In 14 Wistar rats the inferior alveolar nerve was prepared and treated with Carnoy's solution. Varying with the time of application, the histological examination showed extensive nerve injury involving the destruction of myelin and macrophage invasion.

[Results with the use of the SCC antigen in squamous cell carcinomas of the oral cavity]. / Erfahrungen mit dem SCC-Antigen beim Plattenepithel-Karzinom der Mundhöhle.

The serum concentration of squamous-cell-carcinoma antigen (SCC) and carcinoembryonic antigen (CEA) in 51 patients with squamous cell carcinoma of the oral cavity were compared to those of 53 patients with non-malignant disorders of the head and neck. The sensitivity found for SCC was only 24%, but was much higher than for CEA. SCC could be a valuable tool in follow-up monitoring of patients treated for squamous cell carcinomas of the oral cavity.