Biomedical subjects
Publications and source records attributed to Z Suba.
A rare case of a 10-year-old girl with an endodermal sinus tumor that occurred in the nasal cavity is presented. She received chemotherapy and radiotherapy at the age of 4. The subsequent abnormal development of the maxillary teeth is described and discussed in the light of the known effects of radiotherapy.
Short- and medium-term experience with a pure-phase beta-tricalcium phosphate bone-substitute material (Cerasorb) is reported on the basis of clinical, radiological (panorama, 2-3D CT records) and histological examination on 52 patients. The treatment modes on these patients included the filling of cysts, sinus grafting, augmentation and the filling of parodontal lesions. Disturbance of wound healing was not observed in any of the cases, and both the radiological and the histological examinations revealed that transformation of the implanted beta-tricalcium phosphate into bone could be detected as early as in the second month. During the 10-month follow-up period, this transformation was continuous, but was not complete; completion is to be expected only after 12 months. It is important that load-bearing tissue had already developed after 4-6 months. Studies to date suggest that autologous bone is not necessary for either sinus grafting or the filling of large cysts: Cerasorb alone is suitable for this purpose.
Clinical and histologic evaluations of a synthetic bone were performed in 224 patients in a well monitored environment. This material (Bioplant HTR, Bioplant Inc., South Norwalk, CT) was used to obliterate cysts, treat periodontal defects, correct jawbone contours and deficiencies, and gain sufficient support for the placement of dental implants in maxillary subantral augmentation. Implants were positioned either at the time of the synthetic bone graft or after the new supporting tissue was formed. Evidence of new bone formation between the synthetic granules and host tissue was observed during histological examinations. After the material was placed, tissue that could strengthen and augment the inferior wall of the maxillary sinus formed in 3 months. This was observed both clinically and radiographically. After 8 to 12 months, this tissue provided sufficient hard tissue support for the placement of dental implants. This clinical study reconfirmed the applicability of a synthetic bone for bone replacement and augmentation in oral and maxillofacial surgery. No complications caused by infection, inflammation, or rejection of the implanted graft material were observed.
To elucidate some factors related to the malignant phenotype of an oral tumor with mixed cell population the question has been raised whether the biological behavior of the basaloid or the squamous cells show any difference in an immunosuppressed host organism. Basaloid squamous cell carcinoma (BSCC) surgically removed from sublingual location was xenotransplanted either subcutaneously or in the oral submucosa and the histology, ultrastructures, LDH isoenzyme pattern were investigated. The epithelial origin of the established tumor line (HTB-1) could be recognized according to the characteristic epithelial ultrastructures, while the type of the LDH isoenzymes proved its human origin. The squamous cell population dominating the parent surgical specimen of BSCC regressed during xenotransplantation in the subcutan location, on the contrary the basaloid cells grew and maintained the tumor. Interestingly the basaloid cells transplanted from the subcutis to the oral submucosa generated a squamous cell population with an infiltrative growth pattern. The xenografted BSCC offer a promising model to investigate the contribution of each cell populations in the malignant phenotype. The presented data indicate that the basaloid cells are responsible for maintaining the tumor cell population, but certain malignant features (i.e. infiltrative growth) is associated to the squamous cells which are generated from the basaloid cells only under specific circumstances. Thus this particular model system showed that different malignant features could be associated to the basaloid and to the squamous cell component.
This article describes the long-term follow-up of Bioplant HTR Synthetic bone (HTR: hard tissue replacement) in the human organism, as revealed by clinical, radiological and histological examinations and observations over a period of 5 years. Twenty-nine patients with lesions, 9 keratocysts, 16 radicular cysts, 3 traumatic cysts and 1 odontome were followed continuously during this period. All patients selected for follow-up had two criteria in common: the initial intervention had been performed at least 5 years previously; and the largest diameter of the bone defect was at least 2 cm. In all cases, when large bone defects were filled with HTR, the cavity was eventually filled with newly formed and remodelled bone. The process of ossification was relatively slow. In these cases, complete bony regeneration took up to 5 years. Ossification did not continue in the soft parts around the bone cavity. The histological pictures confirmed complete bone healing over the time.
The effect of complex therapy (intra-arterial chemotherapy and radical surgery) on primary tumours and their metastases was studied in 38 oral squamous cell cancer cases. The therapy had different effect on the primary tumours and their lymph node metastases. There was a close correlation between the number of metastatic lymph nodes and survival. The extension and the chemotherapeutic regression rate of metastatic lesions showed a significant correlation with patients' survival.
Effect of ligation on the vascular permeability in the gingiva and alveolar mucosa encircling the mandibular left 1st molar was studied in rats with and without capsaicin pretreatment. Vascular permeability was assessed by the Evans blue extravasation. Ligation caused a significant augmentation in vascular permeability of the gingivomucosal tissue at day 8 (right: 18.14 +/- 1.68 micrograms g-1; left (ligature): 38.21 +/- 2.43 micrograms g-1, n = 8, p < 0.001) and at day 14 (right: 20.31 +/- 1.71 micrograms g-1: left (ligature): 36.98 +/- 2.73 micrograms g-1, n = 8, p < 0.001). 4 days after ligation, no difference could be observed in vascular permeability in the oral mucosa of the ligated side (left: 23.14 +/- 1.21 micrograms g-1) as compared to the side without ligature (right: 23.5 +/- 1.45 micrograms g-1, n = 8, NS). There was no elevation of vascular permeability of gingivomuscosal tissue around the ligation in rats pretreated with capsaicin either in newborn age (right: 23.92 +/- 1.76 micrograms g-1; left (ligature): 23.51 +/- 2.16 micrograms g-1, n = 8, NS) or in adult age (right: 20.61 +/- 1.62 micrograms g-1; left (ligature): 20.85 +/- 1.07 micrograms g-1, n = 8, NS). Light microscopical studies of oral mucosa revealed, that 8 and 14 days after the ligature placed around the mandibular left 1st molar of the rat, there resulted an accumulation of inflammatory cells in the connective tissue.(ABSTRACT TRUNCATED AT 250 WORDS)
The examinations were performed on thirty patients with biopsy-confirmed squamous cell carcinoma of the oral cavity in clinical stage T2-3No-2M0. The aim of the present study was to perform a histological evaluation of the effect of preoperative intra-arterial treatment of surgically removed tumours and to analyse the correlations with the survival of the patients. The tumour regression (R) was evaluated quantitatively on a scale ranging between 1 and 4 points. The evaluation yielded a value of R1 in 8/30 cases (residual tumour was not found histologically). A tumour of microscopic size (R2) was found in 5/30 cases. Partial regression (R3) was established in 12/30 cases, and a slight response (R4) in 5/30 patients. The histologic picture was evaluated qualitatively on the basis of three arbitrarily chosen parameters. Examinations were made on the morphological picture of the residual cancer (C), the inflammatory reaction of the stroma (S) and the demarcation tendency of the tumour (D) and the sum of these values (A). The higher this point score, the poorer the tumour in question responds. Tumours with a score of A3-5 proved to have a very favourable prognosis in contrast with those with a score of A8-9. For the borderline scores of A6-7 the subsequent fate of the patient was decided by the extent of the original tumour and by the occurrence or not metastases. It is noteworthy that, with a comparatively small number of patients, a significant correlation was demonstrated between the survival and the total qualitative point count (A), the S value and the D value.
Biopsy specimens from 42 oral cancer cases were graded by a histological scoring system which was initiated by Bryne et al. This system was based on both the features of the tumor cells and the relationship between tumor cells and connective tissue. The results suggested significant correlation between the histological score values and the survival, the occurrence of recidive tumors and metastatic tumors.
The tissue reactions of titanium-coated cobalt-samarium magnets were investigated following their full-thickness implantation into the skulls of dogs and pigs (six of each species). The implants, together with the surrounding bone, were removed en bloc 1, 2, 3, 6, 9, and 12 months postoperatively. Following physical and radiological examinations, the excised samples were subjected to histologic investigation. The osseointegration process was observed to follow a normal course around the titanium capsule. The magnetic field did not give rise to any tissue changes that could be demonstrated by means of classical histologic methods.
HTR (hard tissue replacement) polymer was used in a second session to perform 26 sinus floor elevations in 16 patients with dental implantation (Flexiroot, U.S.A.). A period of 6, 8, 10, or 12 months elapsed between the two operations, making it impossible to examine the tissular integration of HTR from both clinical and human histologic aspects. Following the sinus elevation, neither prolonged wound healing nor a rejection reaction was observed in any of the cases. During an 8 to 10 month period, sufficient new bone and fibrous connective tissue had grown between the HTR granules to ensure appropriate supporting tissue for the implantation. Subsequently (12 months), the HTR and the new bone became clinically increasingly harder, forming a union that was difficult to shape. HTR may be stated to be a material suitable for purposes of sinus elevation. In three cases in which the alveolar bone was originally very thin (2 to 3 mm), the resorption of this bone was observed, as a consequence of this the implantation was not performed. The resorption is explained by the inadequate blood supply that developed for surgical-technical reasons, and is not connected with the nature of the material used for the sinus elevation.
In cases of untreated mouth cavity carcinomas cisplatin, farmorubicin as well as a combination of the two have been administered intra-arterially to three groups of patients. Result of the treatment was similar tumor regression in all three groups. Thrombotic complications were more frequent in cases treated with farmorubicin. Possibilities of preventing vein damages are reported on.
The HTR polymer was employed under clinical circumstances. Results supported that the HTR polymer may well be employed for bone replacement. The forming of the support tissue between the plastic granulums has been accompanied with biopsies. Though in some cases giant cell reaction of alien body type have been observed, yet this has never been of such degree that it would have impeded the reception of the stuff. According to the authors opinion after reinforcement of the lower wall of the facial cavity with HTR polymert in 8 to 10 months an enduring suitable support tissue is formed.
This study on selected tumour patients demonstrates relationship between the effectiveness of preoperative, postoperative and palliative intra-arterial cytostatic treatment of tumours of the head and neck and the long-term survival. During the period ranging between 3.5 and 9 years after preoperative treatment of 11 cases, palliative treatment of 6 cases, resulting in 100% tumour regression, and postoperative-adjuvant treatment of 23 cases (selected from 254 cases receiving intra-arterial treatment), local recurrence was observed in 10 cases. The question is raised of the necessity of radical surgery corresponding to the original tumour after preoperative treatment resulting in a completely tumour-free state.
Until now big oral cavity degenerated schwannoms were publishen in the literature. The publication describes two further cases. The x-ray'macroscopic and microscopic images of their cases are known.
A rare case of gouty tophus localized to the temporomandibular joint is reported on by which alimentary troubles were caused. Establishment of clinical diagnosis was rendered more difficult by lack of gauty anamnesis.
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