PubMed Health⌕ Search

Biomedical subjects

F W Neukam

Publications and source records attributed to F W Neukam.

At least 19 recordsLinked to original sources
PubMed2007

[Solitary fibrous tumor in the tongue: case report and review of the literature].

Solitary fibrous tumors (SFT) are rare, mostly fibroblastic tumors usually situated in the pleura. Extrapleural manifestations have been described. However, the oral cavity is an uncommon localisation of this tumor. We report the very unusual case of an SFT affecting the tongue that could be removed completely because of its clear delineation. Intraoperative incisional biopsies were used to exclude malignancy. For definitive classification of the tumor, additional histopathologic examinations had to be carried out. Because SFT exhibit malignant behavior only in exceptional cases and their recurrence after complete removal has never been encountered, surgery can focus on the preservation of undisturbed function of the tongue.

Fibroma↗
PubMed2006

The interleukin-8 (-251A/T) polymorphism is associated with increased risk for oral squamous cell carcinoma.

AIMS: In light of recently found contribution of angiogenic and inflammation-related factors to malignancies, this study investigated the possible association of interleukin-8 gene (IL-8) to increased risk of oral cancer. METHODS: The IL-8 (-251 A/T) polymorphism, which influences IL-8 gene expression, was evaluated by restriction fragment length polymorphism analysis in DNA samples of 158 German and Greek patients with oral squamous cell carcinoma and 156 healthy controls of equivalent sex, ethnicity and age. RESULTS: Significant increase of mutant (A-251) allele, which results in higher IL-8 gene expression, was observed in all patients in comparison to normal controls (P<0.001). The A/T heterozygotes had a two-fold greater risk (odds ratio 1.76, CI 1.11-2.79) for developing oral cancer compared to normal TT homozygotes. Furthermore, significantly increased values of mutant allele frequencies compared to controls were observed in all patients as well as in subgroups of patients with or without positive history of cancer (P<0.05 and P<0.001, respectively) and with or without positive history of thrombophilia (P<0.05 and P<0.001, respectively). CONCLUSIONS: In light to known observations of elevated plasma levels of IL-8 in several types of cancer including oral squamous cell carcinoma, the findings of this study suggest that the mutant allele of the (-251 A/T) polymorphism may be a major contributing genetic factor to risk for oral cancer.

Adult↗
PubMed2006

Plasminogen activator inhibitor-1 polymorphism is associated with increased risk for oral cancer.

In light of the recently observed contribution of thrombosis-related factors to carcinogenesis, we investigated the possible association of plasminogen activator inhibitor-1 (PAI-1) with increased risk for oral cancer. In DNA samples of 104 patients with oral squamous cell carcinoma and 106 healthy controls of comparable ethnicity, age and sex, we studied the 4G/5G polymorphism in the PAI-1 gene, which affects its expression. The mutant 4G allele and carrier frequencies were significantly increased in patients compared to controls (65.9% versus 49.5%; 88.5% versus 69.8% respectively, P<0.01). That increase was even higher in patients with a positive family history for thrombophilia or without one for cancer (P<0.001). Interestingly, significant difference from controls was observed only in patients with cancer stages I and II. These findings suggest that the 4G allele, by resulting in higher PAI-1 expression, is a major contributing factor in early stages of oral oncogenesis. Possibly, increased PAI-1 promotes initial development of oral cancer through regulation of cell detachment and delays further tumor progression by inhibiting vascularization.

Adult↗
PubMed2006

Association of platelet glycoprotein Ia polymorphism with minor increase of risk for oral cancer.

AIMS: In light to association of increased platelet glycoprotein Ia (GPIa) expression with tumor invasion and metastasis in several types of cancer, we investigated the possible contribution of a common polymorphism (C807/T807), affecting the GPIa gene expression, in the development of oral cancer. METHODS: DNA samples of 110 patients with oral cancer and 114 healthy controls were examined by allele-specific polymerase chain reaction followed by electrophoretic analysis. RESULTS: The mutant T807 allele homozygotes were significantly increased in the group of patients compared to the control group (P < 0.001). Furthermore, significantly increased frequency of mutant alleles compared to controls was observed in the subgroup of patients with a positive history for cancer (P < 0.01). CONCLUSIONS: The obtained results indicate that the C807/T807 polymorphism is indeed a genetic predisposing factor which contributes to increased risk for oral cancer.

Alleles↗
PubMed2005

Methylenetetrahydrofolate reductase polymorphism and minor increase of risk for oral cancer.

PURPOSE: We investigated whether the mutant methylenetetrahydrofolate reductase (MTHFR) increases risk for oral cancer. The common germ-line mutation C677T in the MTHFR gene significantly diminishes specific activity of the enzyme, which is responsible for the circulating form of folate. Folate deficiency is associated with increased risk for thrombosis, as well as for several types of cancer, through disruption of DNA methylation, DNA synthesis and deficient DNA repair. METHODS: We searched for the C677T mutation by restriction fragment analysis of PCR products in DNA samples of 110 patients with oral squamous cell carcinoma and 120 healthy controls of comparable ethnicity, age and sex. RESULTS: The number of heterozygotes was significantly different in the two groups (P<0.005), as well as in subgroups of patients with or without a positive family history for cancer, compared to normal controls (P<0.01 and P<0.005, respectively). Furthermore, the subgroup of patients with a positive family history for thrombophilia had a significant increase both in the frequencies of mutant alleles (P<0.01) and heterozygotes (P<0.001) in comparison to normal controls. CONCLUSIONS: The obtained results suggest that the MTHFR mutation is a minor contributing factor in oncogenesis in the oral region, in conjunction with low dietary uptake of folate.

Adult↗
PubMed2005

Onlay augmentation versus sinuslift procedure in the treatment of the severely resorbed maxilla: a 5-year comparative longitudinal study.

Augmentation procedures in the severely resorbed maxilla are standard techniques in preprosthetic surgery. Aim of the present study was to compare onlay bone grafting and sinus floor elevation with autogenous bone grafts in edentulous patients in terms of bone resorption of the posterior alveolar crest and implant survival in a 5-year longitudinal study. A total of 100 patients (53 female and 47 male patients) requiring augmentation using autogenous bone due to a severely resorbed maxillae were evaluated. The degree of resorption and bone quality were preoperatively estimated in panoramic radiographs according to Lekholm and Zarb. The overall 5-year success rate of implants placed after augmentation procedures in the posterior maxilla was 93.1%. Following onlay augmentations 215 out of 235 implant insertions were successful, i.e. a success rate of 91.5% was achieved. In the sinuslift group, 330 out 349 implants remained successful, i.e. a success rate of 94.6% was found. The difference between both groups was statistically significant at the end of the evaluation period. Bone resorption, measured as loss of total bone height in panoramic radiographs, was initially more pronounced following onlay augmentations (>20% after 12 months of observation). The degree of resorption decreased in the further course of the study. Lower resorption rates and a higher overall success rate were demonstrated for the sinus lift group.

Adult↗
PubMed2005

Feasibility of an endoscopic approach to the submandibular neck region--experimental and clinical results.

We have investigated the feasibility of an exclusively endoscopic approach to the submandibular region in four pigs, four cadavers and two women. We inflated the subplatysmal space with carbon dioxide at low pressure. The submandibular gland and the jugulodigastric region were easy to identify once the correct anatomical space had been dissected and inflated. Four endoscopic resections of the submandibular gland were done successfully.

Adult↗
PubMed2005

[Prognosis of the facial profile line using the finite element method].

AIM: The aim of the present study was to verify how realistic the prediction of the clinical appearance of the patient's profile is by using the finite element method to simulate orthodontic and surgical intervention. MATERIAL AND METHOD: This single-case study explains step by step interdisciplinary treatment planning in a case with angle class III. Orthodontic and surgical procedures can be simulated and visualized using the lateral cephalogram and the Onyx Ceph software. The facial profile line is calculated over the skeletal surface using the finite element method. The morphing feature of the Onyx Ceph software is used to create an image of the predicted appearance of the patient's profile using a preoperative lateral photograph. RESULTS: The comparison of the simulated profile and the clinical result after bimaxillary surgery showed high concordance. CONCLUSION: The finite element method represents a useful tool for the prediction of the postoperative appearance in patients undergoing fixed orthodontic appliance and orthognathic surgery.

Adult↗
PubMed2005

Harvesting of bone from the iliac crest--comparison of the anterior and posterior sites.

In 1998 we harvested a total of 127 bone grafts from the iliac crest of 65 male and 53 female patients aged 8-80 years. We measured the quantity of bone obtained, the operating time and the donor site morbidity of the anterior approach (n=81) compared with the posterior approach (n=46). The mean volume of bone harvested was 15 cm(3) (range: 9-25.5) of monocorticocancellous- or bicortico-cancellous bone chips or those from a trephine bur. The mean operating time for the anterior approach was 35 min (range: 22-48), for the posterior approach 40 min (range: 32-55). There were 15 complications, which were limited to those in whom the volume of bone exceeded 17 cm(3). The posterior approach caused less morbidity, notably in the form of significantly less pain and irregularity of gait. The patient has, however, to be repositioned during operation, which added to its total duration.

Adolescent↗
PubMed2005

Effects of distraction forces and frequency of distraction on bony regeneration.

The rate and frequency of distraction have a decisive influence on the regenerative process. We tested a newly developed hydraulic osteodistractor in 12 pigs, which were assigned to have continuous and intermittent osteodistraction of the mandible after osteotomy. The forces necessary to distract the mandible were recorded during intermittent distraction. These data were then used for continuous distraction of the bone. Continuous osteodistraction resulted in intramembranous regeneration of bone, whereas intermittent osteodistraction caused chondroid ossification in the regeneration of the bone. Continuous osteodistraction caused speedier regeneration, and distraction forces were lower than with intermittent distraction.

Animals↗
PubMed2005

Management of spontaneous enophthalmos due to silent sinus syndrome: a case report.

Silent sinus syndrome (SSS) is a rare disease exhibiting unilateral enophthalmos and hypoglobus. A 26-year-old white female presented with right side enophthalmos and hypoglobus. There was no history of previous trauma or maxillary sinus diseases. A CT scan showed an opacified right maxillary antrum with decreased volume and downward bowing of the right orbital floor. From clinical and radiological findings the diagnosis SSS was made. Biopsies were collected from the maxillary sinus for the exclusion of malignancy. Two months later orbital floor reconstruction was carried out. Before antrostomy of the affected maxillary sinus, a relative enophthalmos of 4mm was determined. Five days after antrostomy the value reduced to 2.3mm. During the following 2 months the enophthalmos remained constant. At the end of the operation for orbital floor reconstruction it was 0.1mm. Five days after surgery the relative enophthalmos increased to 0.8mm. The value remained constant during the following 3 months. Initial antrostomy of the affected maxillary sinus may lead to a relevant, spontaneous reduction of enophthalmos. After a minimum period of 2 months a re-evaluation should be made, if a reconstruction of the orbital floor is still necessary for the correction of the globe position.

Adult↗
PubMed2004

[Patients with oral squamous cell carcinoma. Long-term survival and evaluation of quality of life-initial results obtained with two treatment protocols in a prospective study].

INTRODUCTION: In patients with oral cancer the treatment has a strong impact on the quality of life. In recent years different therapeutic concepts have been developed, which include preoperative simultaneous 'neoadjuvant' radiochemotherapy (RCT) and one-stage surgery with tumour ablation and reconstruction. Consideration of long-term survival rates yields substantial evidence that mixed-modality treatment including neoadjuvant RCT is superior to adjuvant therapy concepts based on a surgical approach with postoperative radiation. PATIENTS AND METHODS: In this nonrandomised longitudinal prospective study quality of life was evaluated in two groups made up of a total of 53 patients with squamous cell carcinoma of the oral cavity, 26 of whom underwent neoadjuvant radiochemotherapy with subsequent surgical resection while the remaining 27 received surgical treatment first and then postoperative radiotherapy. The quality-of-life core questionnaire (QLQ C-30) and the head and neck cancer module (H&N 35) of the European Organisation for Research and Treatment of Cancer (EORTC) were used. Long-term survival was estimated according to the Kaplan-Meier test. RESULTS: Postoperatively both groups showed a marked reduction in quality of life, especially in restricted chewing, swallowing and speaking. One year later their quality of life had improved substantially, though without quite reaching the preoperative quality-of-life scores. Both groups showed specific impairments in the symptom scales. With adjustment for the fact that the patients were not randomised, long-term survival was 78% in the neoadjuvant treatment group and 50% in the adjuvant treatment group. CONCLUSION: Temporary limitations in the quality of life can be expected after tumour treatment of the kinds presented here for oral cancer. Neoadjuvant therapy concept is more aggressive and might result in longer disease-free survival. The primary goal should be eradication of the tumour. Nevertheless preservation or reconstruction of a maximum of function is essential for a high level of quality of life. Combined-modality treatments seem to be superior to any kind of monotherapy and should therefore be preferred.

Adult↗
PubMed2004

Hertel exophthalmometry versus computed tomography and optical 3D imaging for the determination of the globe position in zygomatic fractures.

It has been the aim of the present study, to introduce the combination of computed tomography and optical 3D imaging to exophthalmometry and to compare the resulting data to the classic Hertel method. Twenty patients without orbital pathology and 12 patients were included in the study, who were subjected to a preoperative computed tomography. Optical 3D images of the facial surface were assessed and Hertel exophthalmometry was carried out to determine protrusion. In patients with zygomatic fractures the assessment of optical 3D images and Hertel values was repeated 5 days after surgery. Preoperative axial CT slices and postoperative optical contours through the globes were superimposed and the change in protrusion was determined. The protrusion values assessed either by CT, Hertel exophthalmometry or optical 3D imaging for patients without orbital pathology did not show any statistically significant differences between each other. For zygomatic fractures, Hertel exophthalmometry revealed more pronounced protrusion data in four of five cases of a posterolaterally dislocated lateral orbital rim and a higher degree of enophthalmos in cases without dislocation of the lateral orbital rim than it could be proved in the CT slices. The differences between optical measurements and CT data were minimal in patients with zygomatic fractures. The combination of computed tomography as baseline measurement and optical 3D imaging for the follow-up examinations reveal more realistic data in cases of zygomatic fractures than Hertel measurements and should be preferred.

Adult↗
PubMed2004

Morbidity of harvesting of bone grafts from the iliac crest for preprosthetic augmentation procedures: a prospective study.

It has been the aim of the present prospective clinical study to assess the morbidity following the harvest of bone from the anterior and posterior ilium in elective preprosthetic augmentations. Fifty consecutive healthy patients (30 female, 20 male, mean age 52.5+/-9.3 years, range 31 years to 65 years) underwent augmentations of implant sites by iliac crest bone grafts. The bone harvest was carried out in 25 cases from the anterior and in 25 cases from the posterior ilium. The superficial sensory function of the skin was determined quantitatively preoperatively, 7 and 30 days after surgery with the 'Pain and Thermal Sensitivity' Test (PATH Test). On the same occasions subjective pain on a visual analogue scale (VAS) and gait disturbances were documented. In the PATH Test, for the innervation areas of the lateral femoral cutaneous nerve (LFCN) and the superior and middle cluneal nerves (SMCN) a significant impairment of the superficial sensory function could be found after 1 week and a significant tendency towards recovery after 1 month (warm stimulus(FCNpreop) 37.9+/-3.0 degrees C, warm stimulus(LFCNday7): 38.6+/-3.2 degrees C, warm stimulus(LFCNday30): 37.9+/-2.9 degrees C, P(LFCNwarmpreop/day7)=0.023,P(LFCNwarmpreop/day30) =0.886, warm stimulus(SMCNpreop): 36.1+/-2.4 degrees C, warm stimulus(SMCNday7): 36.6+/-2.3 degrees C, warm stimulus(SMCNday30): 36.3+/-4.0 degrees C,P(SMCNwarmpreop/day7) <0.0005,P(SMCNwarmpreop/day30) =0.086). Gait disturbances were seen in seven patients after anterior and in three patients after posterior bone harvest 7 days after surgery (P(gaitdisturbanceanterior/posterior)=0.123). After 1 month none of the patients of both groups showed gait disturbances any longer. The maximum subjective pain level was found on the second postoperative day in both groups. It was significantly higher for the anterior approach (VAS(anteriorday2) 7.0+/-1.5, VAS(posteriorday2) 5.5+/-1.8,P(VASanterior/posteriorday2) =0.004). At day 7 and at day 30, the pain levels did no longer differ significantly (VAS(anteriorday7) 3.7+/-1.4, VAS(posteriorday7) 3.2+/-1.6,P(VASanterior/posteriorday7) =0.165, VAS(anteriorday30) 1.4+/-0.7, VAS(posteriorday30) 1.4+/-0.8,P(VASanterior/posteriorday30) =0.724). Because of the lower morbidity of bone harvest from the posterior ilium in the early postoperative phase compared to the anterior approach it seems that it should be preferred in elective augmentation procedures.

Adult↗
PubMed2003

[Osseous defect regeneration using autogenous bone alone or combined with Biogran or Algipore with and without added thrombocytes. A microradiologic evaluation].

In addition to autogenous bone, a variety of bone substitute materials is used to regenerate bony defects. The aim of the study was to evaluate the reossification of critical size defects in the os frontale of adult pigs ( n=16) with microradiography. The defects were filled randomly with autogenous bone or the bone substitute materials Algipore and Biogran each combined with a defined quantity of autogenous bone. Additionally, platelet-rich plasma (PRP) was added in defined quantities (0.5 ml) in two different concentrations (4-fold and 6.5-fold). At 2, 4, 12, and 26 weeks four animals were sacrificed and the osseous regeneration documented by quantitative evaluation of the microradiographic findings. Microradiographic results in the autogenous bone group showed an earlier PRP concentration-dependent mineralization. Over the whole observation period the peak value of autogenous bone as filler alone could not be reached in both PRP groups. Using Algipore, no accelerated effect of mineralization however could be observed. In our study, Biogran proved to be a defect filler only partially suitable for bony defect healing, no matter whether PRP was added or not.

Alginates↗
PubMed2003

Bone regeneration in critical size defects by cell-mediated BMP-2 gene transfer: a comparison of adenoviral vectors and liposomes.

Large bone defects resulting from nonunion fractures or tumour resections are common clinical problems. Recent studies have shown bone morphogenetic protein-2 (BMP-2) gene transfer using adenoviral vectors to be a promising new therapeutic approach. However, comparative studies of different vectors are required to identify the optimal system for possible clinical trials. This study compares the use of liposome-mediated and adenoviral gene transfer for the generation of autologous BMP-2-producing bone marrow stromal cells (BMSC). Primary BMSC isolated from the rat femur were treated ex vivo with either an adenovirus or a liposome carrying human BMP-2 cDNA. The genetically modified cells were evaluated in vitro and transplanted into critical size defects in the rat mandible in vivo. BMSC treated with a reporter gene vector or untreated BMSC served as controls. The newly formed tissue was analysed by in situ hybridization, radiography and immunohistochemistry. Both groups of genetically modified cells produced BMP-2 for at least 2 weeks, and markers of new bone matrix such as osteopontin and osteocalcin were observed within 2 weeks following gene transfer. In the liposome group, the critical size defects were found completely healed at 6 weeks after the gene transfer, whereas the more efficient adenoviral gene transfer allowed for complete bone healing within 4 weeks. None of the three control groups showed bone healing, not even after 8 weeks. Thus, both liposome-mediated and adenoviral BMP-2 gene transfer to primary BMSC are suitable methods to achieve the healing of critical size bone defects in rats. As liposomes have proven sufficient for this purpose and offer several advantages over any other vector, such as ease of preparation, theoretically no limitation of the size of the DNA, and less immunological and safety problems, they may represent the best vector system for future clinical trials of bone regeneration by BMP-2 gene therapy.

Adenoviridae↗
PubMed2002

[Endoscopically-assisted LeFort I osteotomy in distraction procedures of the maxilla].

PURPOSE: The purpose of this study was to demonstrate the feasibility of combining a minimally invasive endoscopic approach to the maxilla with transverse and sagittal distraction procedures. MATERIALS AND METHODS: Four human cadavers were used for training of a minimally invasive access to the maxilla to perform an endoscopically assisted Le Fort I osteotomy, before this technique was applied in three patients with transverse and sagittal growth deficits of the maxilla. Access to the maxilla was gained through a small mucosa incision in the vestibule to create a visualization port to the maxillary sinus through a bur hole. Landmarks were identified through the endoscope before a Le Fort I osteotomy was performed using straight and angulated chisels of different form and angulation. In two patients, the maxilla was split sagittally to perform a transverse maxillary expansion. In one patient, a buried distractor was applied close to the piriform aperture to correct a sagittal growth deficit in a hypoplastic maxilla. RESULTS: The endoscopic exposure of the maxillary sinus walls from within the sinus, the accurate identification of landmarks, and the creation of a Le Fort I osteotomy was achieved in all cases. Distractor application close to the piriform aperture rendered good stability. CONCLUSION: The results of these case reports indicate that the endoscopic approach to the maxillary sinus allows excellent exposure of the sinus walls to perform an endoscopically assisted Le Fort I osteotomy. The combination of endoscopy and osteodistraction supports the trend toward minimally invasive, less traumatic surgical procedures, especially in individuals still growing.

Adolescent↗