摘要:

Successful attachment of the oral tissues to an endosseous dental implant relies in part on its chemical stability, nontoxic properties and maintenance of normal cell functions in the surrounding tissues. The aim of this study was therefore to investigate these 3 factors experimentally. The corrosion resistance of single crystal sapphire (a ‐αl,O,) implants was analysed with respect to the release of aluminium ions; no ions could be detected in the test solutions. The influence of single crystal sapphire on the behaviour of human epithelial cells and fibroblasts derived from biopsies of the oral mucosa, was studied. The cells were cultured in chemically defined or in low serum‐containing media. Compared to the corresponding control cultures, no effects on cell morphology and growth characteristics were observed. Sapphire rods were in‐serted subcutaneously into rats and tissue responses were examined after 4, 8 and 12 weeks post‐implantation. None or slight reactions were found in the tissues. The combined evaluation of these experimental approaches indicates that single crystal sapphire is a material well suited for biological impl

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020201.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

The aim of the present study was to determine the degree of osseointegration of fixtures in different onlay grafting materials. Hydroxylapatite blocks of 2 different pore sizes and free monocortical bone grafts from the iliac crest were inserted in Gijttingen minipigs and fixed with 2 titanium fixtures. The extent of the bone/implant interface area on the fixture surface was determined from histological specimens by morphometric measurements and related to the total thread surface of the fixtures. Fixtures inserted into bone grafts showed the most complete degree of osseointegration, whereas the smallest bone/implant interface area was found with fixtures inserted into those HA blocks with the smaller pore size. There was a significant decrease in the degree of osseointegration between the host bone site and the augmentation material only with the fixtures inserted into the HA blocks of smaller pore size.

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020202.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

The 15 patients included in this study each had 2‐6 permucosal Branemark osseointegrated implants that had functioned successfully for 18 months or more. They were given a full oral examination which included measurements of probing depth and gingival, bleeding and plaque indices around the implants. Marginal bone reduction during the functional life of the implants was estimated from radiographs. At a separate visit, peri‐implant sulcus fluid (PISF) was collected on filter paper strips from the deepest probing site of each implant. PISF volumes were measured and the samples eluted into buffer. Protease activities in the eluates were determined by fluorimetric assay with peptidyl derivatives of 7‐amino‐4‐trifluoromethyl coumarin. Enzyme levels followed the order: cathepsin B/L>elastase>dipeptidyl peptidase IV>trypsin‐like activity. Total enzyme activities and concentrations both correlated positively with all clinical parameters in linear regression analysis. This was true on both a patient level using mean patient values and a site level using pooled patient data. Nearly all of the site level correlations were statistically significant, though coefficients were generally higher for total enzyme activities than concentrations. Elastase‐like activity gave the best overall correlations of the different proteases measured. Amongst the clinical parameters, correlations were generally best with gingival index and bone reduction. Total enzyme activities had good diagnostic specificity and sensitivity as predictors of clinical parameters and the figures were especially high for elastase‐like activity as a marker of bone reduction. PISF proteases may thus be of value in monitoring tissue responses to osseointe

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020203.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

The aim of this study was to test the effect of chlorhexidine gel application on periodontal health of abutment teeth in patients with overdentures. 19 patients with immediate overdentures were distributed ar random among 2 experimental groups. In these groups, a placebo and chiohexidine gel were daily applied. Patients were recalled at 6‐month intervals over a period of 2 years. In both groups, pocket depth, tooth mobility and bleeding index were initially found to decrease after insertion of the overdenture. In the chlorhexidine group. the bleeding index remained very low over the 2‐year period. whereas in the placebo group. the bleeding index gradually returned to the baseline values. The pocket depth in the chlorhexidine group remained below the baseline value. in contrast to values in the control group. The width of the attached gingiva decreased in both the groups. but less in the chlorhexidine gr

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020204.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

To clarifv more of the tactile function of oral implants, both an interocclusal thickness detection and discrimination task were carried out in 4 different test conditions on 37 patients: t (tooth)/t, i (implant)/t. i/i and d (denture)/0 (overdenture supported by implants). For the interocclusal detection of steel foils. the 50percnt; detection threshold level (RL) in the 4 conditions was 20, 48, 64 and 108 pm, respectively. which indicates significant differences. The ability to discriminate interdental thickness differences was tested with a 0.2 and 1.0 mm standard. It was evaluated as the 75% discrimination level (DL). In the 0.2 mm discrimination task, corresponding DL‐values for the t/t, i/t, i/i and d/o condition were 25, 55, 66 and 134 μm, whereas the 1.0 mm standard gave values of 193. 293, 336 and 348 μm. respectively. All results differed significantly from each other (p<0.05) except for the i/i‐d/o comparison of the 1.0 mm discrimination task where the difference was negligible. The present findings indicate that the tactile sensibility of implants is reduced with regard to natural teeth. Remaining receptors of the peri‐implant tissues might play a compensatory role in the decreased exteroceptive I f

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020205.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

In the present animal experiment. analyses and comparisons were made between the structure and composition of clinically healthy supraalveolar soft tissues adjacent to implants and teeth. 5 beagle dogs were used. The right mandibular premolar region was selected in each dog for placement of titanium implants. while the left mandibular premolar region served as control. Extractions of the mandibular premolars were performed. healing allowed, following which titanium fixtures were installed in the edentolous premolar region. Abutment connection was carried out 3 months later. After another 2 months of healing. plaque control was initiated and maintained for 8 weeks. At the end of the plaque control period. clinical examinations were performed and biopsies harvested from the implant site and the contralateral premolar tooth region. Following fixation and decalcification, all tissue samples were embedded in EPON and examined by histometric and morphometric means. The result from the analyses demonstrated that the peri‐implant mucosa which formed at titanium implants following abutment connection had many features in common with gingival tissue at teeth. Thus, like the gingiva. the peri‐implant mucosa established a cuff‐like barrier which adhered to the surface of the titanium abutment. Further. both the gingiva and the peri‐implant mucosa had a well‐keratinized oral epithelium which was continuous with a junctional epithelium that faced the enamel or the titanium surface. In the periimplant mucosa. the collagen fibers appeared to commence at the marginal bone and were parallel with the abutment surface. All gingival and peri‐implant units examined were free from infiltrates of inflammatory cells. It was suggested that under the conditions of study. both types of soft tissues. gingiva and peri‐implant mucosa. have a proper potential to prevent subgingival I pla

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020206.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY

摘要:

This paper presents a specific technique for maxillary sinus augmentation and simultaneous placement of implants in partially edentulous patients. In such patients. there is from time to time insufficient interarch distance for any type of onlay grafting. Healthy. non‐smoking patients without previous or present sinus pathology. where the radiological and clinicle examination revealed insufficient height and/or width of the remaining alveolar process in the posterior maxillary region, were selected. They were operated on using a mandibular bone graft obtained from the symphyseal region between the mental foramina and placed in the maxillary sinus. The recipient site was prepared by cutting in a rectangular shape the lateral sinus wall into the sinus lining. The bone wall was then separated towards the lateral nasal wall by rotating the inferior portion of the cut sinus wall medially. In the space thus created, the bone graft was placed. Fixtures were installed at the same session. The method described has proved to be uncomplicated to perform under local anesthesia and no major disadvantages for the patient or pre‐ or postoperative complications have so far been obser

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1991.020207.x

出版商:Munksgaard International Publishers    

年代:1991

数据来源: WILEY