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R Schmelzle

Publications and source records attributed to R Schmelzle.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Pneumatization of the zygomatic arch on pantomography].

BACKGROUND: The pneumatized spaces of the zygomatic arch (zygomatic air cell defect) are a clinically asymptomatic variation of the temporal bone. The empty spaces of the articular eminence and temporal bone of the zygomatic arch are depicted on radiographs as a sharply demarcated osteolytic lesion of round or oval shape. The aim of this study was to determine the prevalence and characteristics of the ZACD in our outpatients. MATERIALS AND METHODS: We investigated the panoramic radiographs of 1,084 patients who were treated during 1 February and 31 July 2000. The mean age of the 1,084 patients was 41.9 years (SD: 17.2 years; range: 2-96): 628 patients were male (58%) and 456 female (42%). A ZACD was found in 20 of 1,084 patients (prevalence: 1.85%). The mean age of the patients with a ZACD was 43.2 years (SD: 18.4 years; range: 7-87): 11 were female (55%) and 9 male (45%). RESULTS: A bilateral ZACD was found in 20% (four patients). Interestingly, one of these ZACD patients was a 7-year-old boy. Up to now, it had generally been accepted that pneumatization of the zygomatic arch takes place after puberty with the youngest persons with ZACD being 15 years of age. Our findings should prompt consecutive studies on the prevalence of ZACD in children. This finding can be relevant in patients treated for spreading otitis media or mastoiditis.

Adolescent↗
PubMed2000

[Vascular and neural malformations].

The presentation of vascular and neural malformations in an understandable terminology permits accurate diagnosis, proper treatment, individualized prognosis, and also stimulates studies of pathogenesis. The descriptive classification includes: NF 1 and NF 2; hemangiomas, low- and high-flow vascular malformations, combined malformations, and hypertrophy; and syndromes such as, Parkes Weber, Klippel-Trénaunay, Maffuci's, and multiple dysplasia syndromes. Lymphatic malformations are abnormalities of lymphatic development. The list of treatment includes surgical and nonsurgical treatment. Not all vascular malformations can be successfully treated. Coping with NF is a challenge for both, affected individuals and health care professionals. NF is often associated with a myriad of anomalies that present a lot of problems for plastic surgery. In certain cases watchful waiting seems justified but not in cases of severe problems, giant growth, and local complications.

Adolescent↗
PubMed2000

[Squamous epithelial carcinoma in a Zenker diverticulum].

Zenker's diverticulum is a common anomaly in the elderly patient. Carcinoma in such a diverticulum is a rare but recognized complication of a posterior pharyngeal pulsion diverticulum. We present a case of a 67-year-old patient with a long-standing symptomatic Zenker's diverticulum. The diagnosis of the neoplasm was only achieved intraoperatively. The patient underwent a proximal esophageal resection with lymphadenectomy. Reconstruction was done with a microvascular free jejunal transplant. The postoperative course was uneventful. Wide oncologic surgical resection is the therapy of choice in cases of carcinoma in a Zenker's diverticulum.

Aged↗
PubMed1999

[Titanium magnets on implants as an aid in rehabilitation after tumor treatment].

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.

Bone Transplantation↗
PubMed1999

[Primary solitary malignant schwannoma of the trigeminal nerve, Report of a case and review of the literature].

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%.

Aged↗
PubMed1998

[Tumor reduction of plexiform neurofibroma in the craniofacial and neck area].

Neurofibromatosis type 1 (NF1) is an autosomal dominant hereditary disease of high penetrance and variable expression. Epidemiologic data on craniofacial manifestations are still lacking. Up until now 74 patients with NF1 have been treated at the Department of Oral and Maxillofacial Surgery of the University of Hamburg. Forty-two patients presented periorbital and orbital neurofibromas varying in extension and in the severity of findings of the affected site. Surgical therapy is mainly based on tumour reduction, frequently combined with face-lifting. In our experience neurofibromas of the neck tend to be pseudo-encapsulated, facilitating the preparation of the tumour. On the other hand, identification and preparation of diffuse infiltrating neurofibromas in the trigeminal nerve region are difficult and local recurrence must be expected.

Adult↗
PubMed1998

[Detection of extracellular matrix protein (laminin) in experimental arterial anastomoses].

AIM: To investigate the distribution of Laminin in experimental microvascular surgery. MATERIAL AND METHODS: Autografts (4 mm) of the left common carotid artery in 20 Wistar rats were harvested after 4 weeks. The specimens were investigated immunohistochemically for the demonstration and distribution of Laminin. RESULTS: The demonstration and distribution pattern of Laminin was a function of the accuracy of each single suture. In the intima, the organisation and amount of Laminin was directed to the lumen and dependent from the distance and vitality of the vessel segments' cells. The media had in its axis direction the lowest reparative potency to regenerate the continuity break. The adventitia formed a thick cuff around the anastomosis, which was circularly grown through with Laminin-positive vasa vasorum. The marked myointimal hyperplasia in the area around the anastomosis and in the entire autograft was constituted of Laminin-positive extracellular matrix. CONCLUSIONS: Our results support the demand for a careful and atraumatic suture technique in microvascular surgery.

Anastomosis, Surgical↗
PubMed1998

[Clear cell odontogenic carcinoma in connection with squamous epithelial carcinoma. Case report and review of the literature].

One case of a newly described, rare odontogenic tumor is reported. A literature review of 19 cases lends support to the odontogenic origin and metastatic capability, both regionally and distantly, of the clear cell odontogenic tumor. We conclude that this tumor is malignant, with a tendency to recur locally after surgery. It requires an aggressive surgical approach and should be referred to as a clear cell odontogenic carcinoma. In our patient we saw a clear cell odontogenic carcinoma and a squamous cell carcinoma, both with regional lymph node metastasis. The histological differentiation of this type of tumor from other clear cell tumors is difficult.

Adenocarcinoma, Clear Cell↗
PubMed1997

[Salvage therapy of advanced squamous cell carcinoma of the mouth cavity and oropharynx. Results of interstitial high-dose-rate brachytherapy combined with ablative tumor surgery].

PURPOSE: The clinical effect of high-dose-rate (HDR) interstitial brachytherapy combined with tumor resection was investigated in this retrospective study on patients with recurrent oral and oropharyngeal squamous cell carcinoma. PATIENTS AND METHODS: Oral and oropharyngeal squamous cell carcinoma in 38 patients were treated over a period of 7 years (1988-1994) by HDR interstitial brachytherapy using Gammamed 12i equipment. Pretreatment of patients in terms of irradiation and surgery differed (33 irradiated with a total dose between 60.0 and 75.6 Gy, including 8 patients with additional surgery; 1 patient with surgery alone, and 4 patients without any pretreatment). Indications for interstitial brachytherapy differed according to individual responses to treatment and medical histories. RESULTS: Interstitial brachytherapy was successful in the majority of patients, i.e. complete remission: 12, partial remission: 19, no change: 2, progression: 5. Local control and overall survival including patients with surgical treatment was 59% and 81% at 6 months and 47% and 49% after 12 months, respectively. CONCLUSION: Interstitial HDR brachytherapy with Iridium 192 is recommended in patients with local recurrences or second primary carcinomas after previous external radiotherapy in the head and neck region. Combination of interstitial brachytherapy and surgery is preferable for these patients.

Adult↗
PubMed1997

[Life-threatening swelling of the tongue in antihypertensive therapy with ACE inhibitors].

Although generally showing a low incidence of side effects, inhibitors of angiotensin-converting enzyme (ACE) may in rare cases induce angioedemas, mainly located in the oro-facial area and larynx. The interval between the beginning of the ACE inhibitor therapy and the occurrence of such angioedemas may range from a few hours to a few years. Here, the case of a 53-year-old man with massive swelling of the tongue after dental surgery is presented who had started with ACE inhibitor therapy only 24 h before. At admission to the clinic, obstruction of the upper airway due to the tongue swelling had already progressed so far that fiberoptic intubation was necessary. Additionally, the patient was treated with corticosteroids, antihistaminics and epinephrine, avoiding any further administration of the ACE inhibitor. The swelling resolved within 48-72 h. Dentists and physicians should take into consideration this potential side effect in patients treated with ACE inhibitors.

Angioedema↗
PubMed1997

[Detection of human papillomavirus (HVP)-DNA in oral manifestation of lichen planus].

Human papilloma viruses (HPV) can be detected in different epithelia with the help of the polymerase chain reaction (PCR). The role of HPV in the development of anogenital cancers has been intensively studied, and current evidence shows that most cervical cancers are associated with so-called high risk HPV types (e.g. HPV 16 and 18). HPV-infections can also be demonstrated in oral premalignant lesions and squamous cell carcinomas. Depending on the sensitivity of the detection method, 40-67% of leukoplakias, 2.5-76% of squamous cell carcinomas and 0-87% of cases of lichen planus were described to be infected with HPV 16 or 18. Whether lichen planus can be considered as a premalignant lesion is still controversial. By the use of PCR and hybridization we found infections with the high risk HPV types 16, 18 and 31 in 42% (3/7) of the patients with lichen planus. Further investigations with a higher numbers of cases in combination with the analysis of the viral gene expression as well as the clinical and histological control of the corresponding regions are necessary. The aim of these studies is to find out the prognostic value of the HPV infection for this facultative premalignant disease.

DNA Probes, HPV↗
PubMed1997

[Use of a fibula bone span in alveolar ridge augmentation. Outcome after 2 years].

A preliminary report presenting the results of fibular strut grafting in the severely resorbed mandibular and maxillary region is presented. Thirteen patients were treated due to severe resorption of alveolar and basilar bone of 49 segments of the mandible and the maxilla. Two patients additionally had pathological fractures of the mandible. In 10 cases the strut graft was harvested by means of a new minimally invasive technique. After modelling the fibular bone it was fixed to the recipient site by miniscrews or implants. After a mean follow-up period of 20 months (max. 31, min. 11 months) a retrospective analysis of clinical and radiological findings was carried out. It showed that a mean augmentation of 16 mm was achieved. Compared to other studies the fibular strut graft was resorbed less, and due to the primary stability it could be used for the treatment of fractures of the mandible. No more than natural resorption was observed when the patients received their prostheses fixed to dental implants.

Adult↗
PubMed1997

[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].

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".

Bone Transplantation↗
PubMed1997

[Insertion of autografts after acute damage of the common carotid artery. Experimental microvascular anastomoses after balloon dilatation].

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.

Anastomosis, Surgical↗
PubMed1997

[Face lift: prevention of complications and future developments].

The best treatment for any complication following a face-lift operation is prophylaxis. Well-known complications are hematoma, eschar, necrosis, facial nerve paralyses, injury of the great auricular nerve, loss of hair, keloid formation "dog ear", wound infection, local disfigurement and inordinate relaxation. The reasons are mostly poor selection for the operation by the physician, a poor technique on the part of the surgeon and undesirable changes in the tissue being operated on, reasons that are beyond the surgeon's control.

Adolescent↗