摘要:

An intimate contact between bone and titanium implants was first demonstrated in 1969. and since then the bone‐implant interface of osseointegrated implants has been investigated extensively. However. investigations of the marginal tissues and the microflora associated with osseointegrated implants have almost exclusively been carried out over the last decade. This review covers the clinical, radiographic, histologic, and microbiologic studies of marginal tissues of osseointegrated oral implants. In general, successfully osseointegrated implants exhibit low amounts of plaque con‐comitant with the absence of marginal inflammation. However, plaque accumulation may cause inflammatory reactions around the implants, sometimes giving rise to mucosal hyperplasia. Apparently, keratinized mucosa is not a requisite for the maintenance of peri‐implant health if oral hygiene is adequate, but the presence of peri‐implant keratinized mucosa is generally advocated. Alveolar bone loss around successful implants is minimal, but significant focal loss may occur due to plaque‐induced inflammation or perhaps repeatedly extensive implant load. The progression of plaque‐induced alveolar bone loss of osseointegrated implants may be different from that of teeth. It is unknown whether simultaneous marginal inflammation and excessive implant load further increase the loss of alveolar bone height. Both the light microscopic and ultrastructural characteristics of marginal tissues of implants and teeth are similar except for a lack of root cementum with inserting gingival collagen fibers of implants. Clinical inflammatory reactions are histologically characterized by an increased number of inflammatory cells infiltrating the connective tissue. The scattered subgingival microbiota associated with osseointegrated implants surrounded by healthy or slightly inflamed marginal tissues is similar to that of teeth with healthy gingiva. The microbiota associated with implants affected by marginal inflammation and bone loss is complex and consists predominantly of gram‐negative anaerobic rods: this. again, is a similarity to period

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030401.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

The purpose of this study was to investigate the possibility of antimicrobial treatment of peri‐implant infections associated with a periodontitis‐like subgingival microbiota. Nine partially or fully edentulous patients with titanium hollow cylinder implants were selected which showed loss of bone and probing depths ≥ 5 mm on one or several implants after at least 6 months following installation. They also yielded subgingival microbial samples with ≥ 106CFU/ml, including ≥ 20% gram‐negative anaerobic bacteria, The treatment included mechanical cleaning, irrigation of all peri‐implant pockets>3 mm with 0.5% chlorhexidine and systemic antimicrobial therapy (1000 mg ornidazole for 10 consecutive days). After therapy, bleeding scores decreased immediately and, over a one‐year observation period, remained significantly lower than before treatment. A significant gradual reduction in mean probing depths was detected over this one‐year period; only one case showed no improvement of local probing depth. Microbiological parameters indicated an instantaneous quantitative and qualitative change following treatment. Subsequently, several of these parameters tended to shift back towards pre‐treatment values. In the second half of the observation period, however. this tendency was reversed, and levels significantly different from baseline were eventually established. This study demonstrated that treatment aiming at reducing the subgingival bacterial mass and suppressing the anaerobic segment had a beneficial effect in patients suffering fr

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030402.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

Eight non‐submerged titanium implant screws were placed in the first upper molar edentulous sites of monkeys and subsequently kept loaded with single crown prosthesis 1 month following implantation. The animals were killed after a further 14 months and specimens including implant and adjacent teeth were processed for light and electron microscopy. Histological pictures of all samples showed the neck and most of the screw body to be surrounded by new bone. The soft tissue surrounding the implant post included pocket epithelium and supra‐crestal connective tissue displaying collagen fiber bundles comparable to gingival ligaments. These peri‐implant collagen fiber bundles arose from the neighboring alveolar crest, root cementum of adjacent teeth or, superficially, from the epithelium and followed a circular array around the implant

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030403.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

In 21 individuals, edentulous in the upper jaw, the speech function was evaluated. In an earlier study, registrations were made when the patients wore complete dentures in the upper jaw and 3–6 months after they had been treated with fixed prostheses on osseointegrated implants in the maxilla. These patients were re‐examined after 3 years, as reported in this follow‐up study. An expert group as well as a non‐expert group participated in a perceptual analysis. Acoustic, audiological and cast analyses were performed. In addition, a questionnaire was filled in. The results indicated that, after initial phonetic problems, 94% of the individuals considered themselves free from speech problems at the 3‐year follow‐up. The patients' experience of the change of the s‐sound corresponded well with the judgement of both the expert and the non‐expert groups. Difficulties with pronouncing the s‐sound were associated with decreased bite force, the number of occluding contacts, the frontal width of the fixed prosthesis and tenderness at palpation of the masticatory muscles. These oral functional factors will contribute to the s

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030404.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

Several parameters have been described to determine success or failure in long‐term evaluations of dental implants. One of these parameters is the observation of changes in peri‐implant bone levels. Studies on submerged implants have analyzed the bone level changes in the pre‐ and post‐loading phases. No such data exist for intentionally nonsubmerged implants. The purposes of this study were: (1) to test the applicability and reproducibillity of a simple computer‐assisted method in the evaluation of changes in peri‐implant bone levels;(2) to establish a baseline for the longterm radiographic follow‐up; and (3) to evaluate changes in crestal bone levels adjacent to nonsubmerged IT1 implants between the 1‐year and 2‐year examination. Standardized periapical radiographs were obtained from 80 implants at the l‐year and 2‐year follow‐up examinations after their placement. The implants were located in different jaw areas of 55 patients and supported single crowns or short‐span fixed partial dentures. For each implant, the distance from implant shoulder to first crestal bone contact (DIB) was measured at the proximal surfaces with a digitizer/computer assembly. Statistically significant greater mean DIB were found at the l‐year (baseline) evaluation for: (I) maxillary sites overall (4.10 x 1.02 mm (SD)) compared with mandibular sites overall (3.61 ± 1.03 mm);(2) maxillary anterior sites (4.08 ± 0.97 mm) compared with mandibular posterior sites (3.60 ± 1.05 mm); and (3) maxillary posterior sites (4.13 ± 1.12 mm) compared with mandibular posterior sites. No statistically significant changes in DIB occurred in any of the jaw locations between the l‐year and 2‐year evaluations. These results indicate similar changes in peri‐implant bone levels for non‐submerged implants over a 2‐year pe

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030405.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY

摘要:

The purpose of this research was to determine the nature of the residual hydroxyapatite (HA)‐coated implant surface after treatment with various chemotherapeutic modalities, including: citric acid, chlorhexidine gluconate, hydrogen peroxide, tetracycline HCl, stannous fluoride, polymyxin B and a prototype plastic Cavitron tip. Implant surfaces were evaluated macroscopically, microscopically (scanning electron microscopy (SEM)) and spectrometrically (energy‐dispersive spectrometry and X‐ray diffraction). HA‐substrate bond strength and dissolution testing was also performed for surfaces treated with a supersaturated citric acid solution. All treatments left either microscopic residues or a loss of surface roughness when viewed on SEM. A 30‐ to 60‐s application of citric acid left a significantly greater coating thickness than all other treatments, whereas a 3‐min application of citric acid removed significantly more HA than untreated controls. Significant changes in CaiP ratios were seen with most treatments. The clinical significance of this phenomenon is not known. No treatments altered the crystallinity of the residual HA coating. A l‐min application of citric acid did not significantly alter the tensile bond strength of the coating to the substrate. The clinical significance of these findings is not known at present. However. when taken with results from previous studies. it appears that in treating the infected HA‐coated implant surface, a 30‐ to 60‐s application of citric acid (pH 1) may be beneficial in detoxifying the HA coating prior to regenerative procedures. Further in vitvo and in viva studies are necessary to evaluate the biological response to citric acid when used to detoxify the inf

ISSN:0905-7161    

DOI:10.1034/j.1600-0501.1992.030406.x

出版商:Munksgaard International Publishers    

年代:1992

数据来源: WILEY