[Recommendation of the Hungarian Society for Face, Mandible and Oral Surgery in the indication of supportive therapy with Avemar].
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Publications and source records attributed to Zsolt Németh.
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It is an important modern trend to try to modify the surface properties of titanium implants with titanium oxide produced in various ways. One possibility of surface modification is the formation of an oxide layer by heat and electric treatment. The authors examined three osteosynthesis plates treated with anodic oxidation of Hungarian development. 5-10 microm thick slides were made of the plates in several cross sectional planes with a special cutting-grinding technique and were examined under a microscope with various magnifications. In the study it was seen that the surface of the basic metal was covered with a continuous oxide layer in all the cross sectional planes. No material faults were discovered on the surface. The thickness of the surface layer in various regions was found to be changing in the nm range, which coincides with the results of other studies. It was proven in the study by using the surface modification technique in part developed by the authors a passivating layer was formed on the surface of titanium, which separates it from the human organism.
BACKGROUND: The radical removal of mesopharyngeal tumors necessitates very extensive, aggressive surgery. In certain cases, therefore, they strive to ensure the quality of life of these patients by means of two other possibilities in the complex treatment: chemotherapy and irradiation; in this way, over radicality can be avoided. AIM: One of the elements of the complex therapy may be intraarterial chemotherapy. The present work relates to a study of the effects and side-effects of primary intraarterial chemotherapy administrated in the period 1995-2000, and the overall survival of the patients. PATIENTS AND METHOD: Remission was attained in a total of 30 patients who participated in primary intraarterial chemotherapy. The degree of severity of any complications that occurred was studied, as was the duration of survival. Treatment was performed by retrograde cannulation of the external carotid artery and the administration of a relatively low dose of drug for a relatively long time (5-14 days). The intra-arterial chemotherapy was supplemented with other modes of treatment. RESULTS: A clinically observable degree of tumor regression was detected in 83.3% of the cases after the intraarterial treatment. The 5-year survival rate was approximately 30%. CONCLUSIONS: The overall survival rate for oropharyngeal carcinoma patients treated with combined procedures is reported to range between 32% and 83%. Since our patients (with 2 exceptions) were in stage III or IV, and in many cases were inoperable, our 5-year survival rate of approximately 30% may be stated to be acceptable, while the quality of life of the patients was much more favourable than following the primary radical operation.
Knowledge of the course of the mandibular canal and its anatomic variations is of great importance in oral surgery, especially in preprosthetic operations and the insertion of endosteal implants and during the planning of removable dentures prepared in cases involving extensively atrophied mandibles. We review the literature on duplicated mandibular canals, which is based exclusively on radiologic findings. Then, we compare this with an examination of dry mandibles and further radiologic studies. The incidence of duplicated mandibular canals observed in macroscopic examinations of mandibles was substantially higher than that revealed by radiographs. One case involving a novel variation, a triple mandibular canal, is reported.
The authors review the literature relating to anatomical variations of mandibular canals. They compare the results of their examinations with the literature data. The proportion of duplicated mandibular canal observed during macroscopic examinations of mandibles proved to be substantially higher than that revealed by X-ray pictures. The knowledge of the course of the mandibular canal and its anatomical variations is of great importance in certain oral surgical interventions, such as preprosthetic operations and the insertion of enosseal implants, and during the planning of removable dentures prepared in cases involving extensively atrophied mandibles. The authors review the possible consequences of the injury of accessory mandibular canal.
Syndecan-1, a transmembrane proteoglycan, may exert anti-proliferative effects and promote cell growth by binding various growth factors. Malignant epithelial cells often down-regulate their own syndecan-1 production, and are capable of inducing an aberrant syndecan-1 expression in stromal fibroid cells. Decreased tumor cell syndecan-1 levels in human head and neck squamous cell carcinomas indicate poor prognosis, however, no correlation between stromal syndecan-1 expression and clinical parameters has previously been established. By means of immunohistochemistry, we observed a decrease in tumor cell syndecan-1 reactivity in 33/39 oral carcinoma cases, the degree of which, however, correlated only weakly with the clinical outcome (p = 0.097). Conversely, stromal syndecan-1 positivity proved to be a significant risk factor of recurrence (Cox analysis, p = 0.03) and tumor-specific death (p = 0.023) within a 24-month period after operation. Taken together, stromal expression of syndecan-1 is a reliable factor of adverse prognosis in oral carcinomas.
Arthropods and in particular spiders are a common embodiment of our fears, despite the fact that only a few species are dangerous to man. The authors present a case involving severe local and general reactions to a loxosceles (brown recluse spider) bite. They give an overview of the occurrence of loxosceles spiders, the signs and symptoms of envenomation and the therapeutic possibilities. The severe symptoms presenting following loxosceles envenomation is termed loxoscelism. Loxoscelism is characterised by local soft tissue necrosis of varying degree at the site of the sting, and rarely, life-threatening general reactions, such as haemolysis with ensuing anaemia, and renal failure. Therapeutic interventions following loxosceles bites range from dapsone treatment to hyperbaric oxygen therapy, but the most promising therapy is the use of the antiserum, commercially available in certain South-American countries where loxosceles bites are common. Treatment of soft tissue necrosis consists of necrectomy and surgical reconstruction following the resolution of the inflammatory symptoms.
Sixty patients with tumors of the floor of the mouth or of the tongue (T2N0-1-2M0) were randomized into three treatment groups. The first two groups participated in low-dose inductive chemotherapy, surgery, and then radiotherapy, whereas the third control group underwent only surgery and radiotherapy. In all three groups, studies were made of the stage, grade, sex, localization, extents of expression of the pretreatment laminin and syndecan-1 and the cancer specific survival rate, and the correlations among these. The response to neoadjuvant chemotherapy was assessed by means of a method that we developed, involving measurement of the degree of histologic regression observed in response to chemotherapy. Immunohistochemical methods were applied to investigate the changes in degree of expression of laminin and syndecan-1 in response to the medication and their correlations with the survival. As concerns the overall tumorfree survival rate, a significant difference was not found between the two chemotherapeutic groups. However, there was a significant difference between the survival indices of those who participated in cytostatic treatment (70%) and the control group (40%). In the clinical and immunohistochemical examinations, the initial laminin and syndecan-1 levels obtained from biopsy samples could be used as prognostic factors. Our model measuring the extent of histologic regression clearly demonstrated that the survival indices of the patients who responded to the neoadjuvant cytostatic treatment with adequate tissue regression were better than those of the patients who responded to the treatment to only a decreased extent or not at all. The changes in the expressions of laminin and syndecan-1 in response to cystostatic treatment proved to be important predictive factors. The increase or stagnation of these clearly forecast a good prognosis, whereas their decrease was a definite indication of poor prognosis.
Despite the considerable advances in the diagnostic and therapeutic possibilities, the prognosis of epithelial tumors in the oral cavity is very poor. A knowledge of the prognostic factors at the beginning of treatment is therefore indispensable for determination of the appropriate therapy for the given patient. These factors may be linked to the patient (e.g. age, sex, general condition and immunological parameters) or to the tumor (localization, TNM stage, histological features, DNA content, or immunohistochemical and other parameters). A survey of the literature reveals that the TNM stage, the grade, the mode of invasion and the depth of the tumor are generally the most important factors influencing the fate of the patient. The prognosis primarily depends on the clinicopathological parameters, though even if they are known, it is not possible to screen out those patients who are at particular risk of a relapse. During the past 10 years, study of the DNA content, the proliferation markers and certain oncogenes has came into the focus of attention; great interest is also shown in the matrix metalloproteinases, which play key roles in the invasion and metastasis formation.
BACKGROUND: Numerous possibilities are available for the reconstruction of facial bone defects. The materials used to fill such defects must satisfy various requirements. One of the most important is that they must undergo transformation into autologous bone tissue in the process of remodeling. AIM: A report is given of the long-term results of augmentations of large bone defects performed with different bone-substitute materials in two patients. PATIENTS AND METHODS: In one case, augmentation was carried out with beta-tricalcium phosphate after the removal of a fibromyxoma. In the second case, three large cystic lesions in the mandible of a patient with Gorlin-Goltz syndrome were filled with beta-tricalcium phosphate, with a mixture of beta-tricalcium phosphate and platelet concentrate, or with hydroxyapatite of algal origin. The process of ossification was checked at 6-month intervals by means of clinical, radiologic (orthopantomograms and two-dimensional and three-dimensional computer tomograms), and histologic methods. RESULTS: At 1 year after the intervention, the site of the augmentation was in all cases occupied by hard tissue of good quality. With the given imaging procedures, it was difficult to distinguish between the original bone and the region filled with bone-substitute material. The three-dimensional computer tomogram images indicated that the contours and quality of the new bone corresponded with the physiologic and anatomical conditions. The histologic examinations show the remodeling of the bone-substitute materials. DISCUSSION: The bone-substitute materials applied in these cases fully satisfied the demands of transformation into bone (remodeling). The speed of remodeling seemed to be the fastest when the mixture of beta-tricalcium phosphate and platelet concentrate was used.
One of the surgical procedures preceding implantation is elevation of the base of the maxillary sinus. Numerous bone substituting materials (grafts) may be used for this purpose, including autogenous bone, heterografts, xenogenous bone, and synthetic materials alone or in combination or mixed with growth factors and bone morphogenetic protein (BMP) preparations. A study of the frequencies of the failures (graft material resorption or implant loss) after sinus elevations with various graft materials or their combinations was conducted. In the 5-year period from 1996 through 2001, a follow-up investigation of 810 maxillary sinus augmentations was performed, in which the sinus elevations involved the use of autogenous bone, a calcium carbonate-coated polymer, hydroxylapatite of algal origin, calcium carbonate gel produced from coral or beta-tricalcium phosphate alone, autogenous bone mixed with these bone substitutes, or a combination of beta-tricalcium phosphate and platelet-rich plasma. The incidences of graft resorption and implant loss after the augmentations with various bone substitutes were recorded. Total resorption (disappearance) of the bone substitute material was observed in 2.7% of the cases. An essential difference was not experienced between the various bone substitutes from this aspect, with the exception of the gel-state calcium carbonate, where 40% of the grafts were resorbed. In total, 5.46% of the implants were lost; the differences between the various materials were not significant.
A case is reported in which a unilateral parotid gland cystadenolymphoma was combined with actinomycosis. A 48-year-old woman presented with a mass in the left parotid region and paresis of the lower left palpebra. The computed tomography, echography, and parotid radiographic findings did not exclude a neoplasm of the left parotid gland. The ramus of the mandible was involved in the process. Intraoperative freezing histology, total parotidectomy, and partial mandibulectomy were performed, with sacrifice of the facial nerve followed by nerve reconstruction. The final histological evaluation was Warthin tumor with actinomycosis. Four years after treatment, the patient is free of disease. No similar cases seem to have been reported thus far.
INTRODUCTION: When the maxilla is edentulous and the alveolar process is extensively absorbed, a dental root can be implanted only after the implantation of bone or a bone-substitute. Only in this way can the subjective and objective negative features associated with a removable prosthesis be avoided. Many forms of bone-substitutes are known. Freely taken bone from the patient generally serves as the gold standard for the classification of bone-substitutes. AIMS: The aim of our work was to compare two materials (the patient's own bone and beta-tricalcium phosphate) in the same patient. METHODS: Ten patients were selected who for some reason did not want or could not wear a removable prosthesis. The maxilla was so atrophied that bone or bone-substitute implantation was necessary before the dental root could be implanted. The maxilla had to be elevated from inside (sinus elevation) and thickened from outside (onlay-plasty). Bone was taken in the usual manner from the hipbone. For the internal elevation, such autogenous bone was utilized on one side, and beta-tricalcium phosphate granulate on the other. The formation of new bone and the rate of bone formation were followed by clinical methods and by radiological, histological, and histomorphometric examinations. RESULTS: The implantation succeeded clinically in all ten patients: one year later they all received a fixed bridge. The radiological and histological examinations demonstrated good bone formation on both sides. As concerns the rate of formation of new bone, there was practically no difference after the implantation of autogenous bone or beta-tricalcium phosphate. CONCLUSIONS: This study has therefore provided further evidence that, when certain bone deficiencies are to be eliminated, the unpleasant phenomena accompanying the removal of the patient's own bone can be avoided through the use of new synthetic materials. Accordingly, when comparing the present results with the findings of other authors, beta-tricalcium phosphate may be considered a good graft material even without autogenous bone.
Transformation of the surface of metallic titanium with titanium oxides prepared in various ways is a modern procedure. For more than 15 years, the authors have been utilizing fixing elements coated with titanium oxide ceramics, prepared by anodic oxidation and thermal treatment, for purposes of jawbone osteosynthesis. The aim of the authors' work was to assess the extent to which the titanium oxide ceramic coating influences the fate of the plates used for osteosynthesis within the human organism, in regard to the possible need for their removal. During a 5-year period, 108 of 1,396 plates coated with anodic titanium oxide had to be removed for various reasons: plate exposure (47), osteomyelitis (25), palpable swelling and tenderness (21), patient request for psychological reasons (13), or fracture of the plate (2). In none of these 108 cases was metallosis observed, which otherwise is reported relatively frequently in the vicinity of traditional titanium fixing elements, nor was any tissue damage connected with the surface of the plates. The results indicate the favorable properties of the titanium oxide ceramic surface.
Transformation of the titanium metal surface with titanium oxides produced in various ways belongs among the most up-to-date procedures. The authors as pioneers in this field (e.g. Nobel Biocare TiUnite surface), have been utilizing for more than 15 years dental root implants and fixing elements (for mandibular osteosynthesis) coated with titanium oxide ceramics, produced by anodic oxidation and thermal treatment. The aim of this work was to assess the extent to which a titanium oxide ceramic coating influences the fate of plates applied for osteosynthesis within the human body. During a 5-year period (1995-1999), 108 of 1396 titanium oxide ceramic plates had to be removed for various reasons: loosening of the plate [47], osteomyelitis [25], a palpable swelling and tenderness [21] at the request of the patient for psychological reasons (13) or breaking of the plate [2]. When these 108 plates were removed, it was not possible to detect metallosis in even a single case; nor was there any tissue damage that could be attributed to the surface of the plates, whereas the literature data indicate that such damage is relatively frequent in the environment of traditional titanium fixing elements. The present investigation confirms the favourable properties of the titanium oxide ceramic surface.
Following tooth loss, augmentation of the extensively atrophized alveolar ridge of the maxilla may be necessary, in order to restore the masticatory function by the replacement of teeth anchored on implants. A number of bone augmentation methods are available for the acceptance of implants. The aim of the presented report is to summarize our experience relating to the use of free monocortical bone grafts originating from the hip (spina iliaca anterior superior) for purposes of onlay-plasty.
The authors discuss 3 cases of Gardner-syndrome, outlining malignized large intestine polyposis, multiplex osteomas and the different skin tumours as the main features. The earliest symptoms suspecting the clinical picture are usually dental and/or mandibular lesions and draw the attention to the highly malignant polyposis.
PURPOSE: Two different graft materials, beta-tricalcium phosphate (Cerasorb) and autogenous bone, were used in the same patient. The objective was to determine whether donor site morbidity could be avoided by using pure-phase beta-tricalcium phosphate (Cerasorb). MATERIALS AND METHODS: Bilateral sinus grafting was performed on 20 selected patients; Cerasorb was used on the experimental side, and autogenous bone was used on the control side. In each patient, one side was randomly designated the experimental side. In 10 of the 20 patients, the maxilla reconstruction included sinus grafting and onlay bone grafting. Implants were placed 6 months after the procedure. In addition to routine panoramic radiographs, in 10 of the 20 patients, 2- and 3-dimensional computerized tomographic examinations were performed pre- and postoperatively and after implantation. Eighty bone biopsy specimens were taken at the time of implant placement. RESULTS: Histologically and histomorphometrically, there was no significant difference between the experimental and control grafts in terms of the quantity and rate of ossification. For each histologic sample, the total surface area, the surface area that consisted of bone, and the surface area that consisted of graft material were measured in mm2, and bone and graft material were analyzed as percentages of the total. The mean percentage bone areas were 36.47% +/- 6.9% and 38.34% +/- 7.4%, respectively; the difference was not significant (P = .25). DISCUSSION AND CONCLUSION: Comparisons with other studies reveal that beta-tricalcium phosphate (Cerasorb) is a satisfactory graft material, even without autogenous bone.