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R Adell

Publications and source records attributed to R Adell.

At least 19 recordsLinked to original sources
PubMed1990

Long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws.

This study reviews the long-term outcome of prostheses and fixtures (implants) in 759 totally edentulous jaws of 700 patients. A total of 4,636 standard fixtures were placed and followed according to the osseointegration method for a maximum of 24 years by the original team at the University of Göteborg. Standardized annual clinical and radiographic examinations were conducted as far as possible. A lifetable approach was applied for statistical analysis. Sufficient numbers of fixtures and prostheses for a detailed statistical analysis were present for observation times up to 15 years. More than 95% of maxillae had continuous prosthesis stability at 5 and 10 years, and at least 92% at 15 years. The figure for mandibles was 99% at all time intervals. Calculated from the time of fixture placement, the estimated survival rates for individual fixtures in the maxilla were 84%, 89%, and 92% at 5 years; 81% and 82% at 10 years; and 78% at 15 years. In the mandible they were 91%, 98%, and 99% at 5 years; 89% and 98% at 10 years; and 86% at 15 years. (The different percentages at 5 and 10 years refer to results for different routine groups of fixtures with 5 to 10, 10 to 15, and 1 to 5 years of observation time, respectively.) The results of this study concur with multicenter and earlier results for the osseointegration method.

Adult↗
PubMed1990

Reconstruction of severely resorbed edentulous maxillae using osseointegrated fixtures in immediate autogenous bone grafts.

A surgical technique for rehabilitation of severely resorbed edentulous maxillae using fixed prostheses or overdentures supported by osseointegrated fixtures in immediate autogenous corticocancellous bone grafts from the ilium is described. The results of the first 23 consecutively treated patients are reviewed. The mean observation time was 4.2 years (range 1 to 10 years). A total of 124 fixtures was originally placed into the grafts, supplemented with 16 fixtures inserted later into seven of the jaws. Throughout their observation period, 17 of the patients had continuously stable prostheses. The remaining five had overdentures, and one patient had resorted to a conventional complete denture. After 4 years, 12 of 16 patients had continuously stable prostheses. Corresponding values at 5 years were 7 of 8 patients. Calculated from the date of abutment connection, 82.1% and 81.6% of the original fixtures were clinically stable and radiographically osseointegrated after 4 and 5 years in function, respectively. From the date of fixture placement, the corresponding figures were 75.3% and 73.8%, respectively. The mean marginal bone loss after the first year of prosthesis function was 1.49 mm. The annual marginal bone loss thereafter was about 0.1 mm. The results indicate that this technique is worthwhile for patients with extreme maxillary atrophy and who cannot wear conventional complete dentures.

Adult↗
PubMed1989

Osseointegrated implants in the treatment of partially edentulous patients: a preliminary study on 876 consecutively placed fixtures.

A total of 876 consecutively placed fixtures ad modum Brånemark was followed in 268 partially edentulous jaws of 244 patients treated between April 1968 and the end of December 1988. A total of 24 of 712 fixtures exposed at the abutment connection was lost (3%); the continuous prosthesis stability rate was 98.7%, as only four of 293 prostheses were removed. The results of the study indicate the possibility for the Brånemark osseointegration technique also to be used in the treatment of partial edentulism.

Adolescent↗
PubMed1987

Accuracy of cephalometric prediction in orthognathic surgery.

The reliability of predicting the results of orthodontic surgical treatment was analysed. The sample consisted of 30 patients treated with one of the following six types of surgery: mandibular anterior alveolar surgery; maxillary anterior alveolar surgery; mandibular setback surgery; mandibular advancement surgery; Le Fort I surgery; and a combination of Le Fort I and mandibular setback surgery. Comparisons of tracings of the initial cephalometric radiographs, the prediction tracing and the six-month follow-up film showed great variation in the results both within and between the surgical subgroups. Generally, it was easier to predict the treatment results of alveolar segmental osteotomies, especially in the mandible, than of operations in which the whole mandible was repositioned. The results from Le Fort I surgery with or without a concomitant mandibular setback showed the greatest difference between the predicted and the actual outcome. The postoperative vertical dimension appeared to be particularly hard to predict. Explanations for these discrepancies are offered and possibilities for improvements suggested. It is concluded that prediction tracings are still of value despite the poor accuracy in some cases.

Adolescent↗
PubMed1987

Delayed healing of fractures of the mandibular body.

401 mandibular body fractures occurring during a 5-year period were analysed retrospectively. Out of these, 38 fractures (9.5%) were not consolidated by 50 days and made up the delayed healing group (DHG). A control group (CG) of another 38 fractures was constituted using the first mandibular body fracture consecutively following one in the DHG. The mean time until consolidation of the fractures was 116 days in the DHG and 35 days in the CG. The 2 groups were statistically analysed and mutually compared using a great number of variables including patient-, fracture site-, treatment- and end-result characteristics. It was concluded that a few days delay between trauma and treatment did not necessarily lead to a delayed healing. Uncooperative alcoholics with psycho-social handicaps, and general as well as local periodontitis, were found to be especially liable to consolidate their fractures at a slower rate than the average patient. The DHG more often required changes of unstable dental fixation, prolonged maxillo-mandibular fixation time and treatment for late infections at the fracture site. The patients in this group lost more teeth than those in the CG but above all required considerably extended therapeutic efforts. It is suggested that patients with the above-mentioned characteristics should be given special attention and care.

Adult↗
PubMed1986

Temperatures during drilling for the placement of implants using the osseointegration technique.

The temperatures elicited during drilling according to the osseointegration technique were measured in vivo in five edentulous human mandibles. The temperature changes were measured by a thermocouple, the tip of which was situated 0.5 mm from the drill surface and separated from it by a cortical wall. Eighteen measurements showed a mean initial temperature of 29.2 degrees C before drilling and a mean maximum temperature of 30.3 degrees C during drilling. The maximum temperature recorded was 33.8 degrees C. The duration of the maximum temperatures never exceeded 5 seconds. All temperatures recorded were below the level for impaired bone regeneration. It was concluded that drilling according to the osseointegration technique does not cause any impaired bone regeneration because of excessive heat production.

Adult↗
PubMed1986

Marginal tissue reactions at osseointegrated titanium fixtures (I). A 3-year longitudinal prospective study.

16 consecutive totally edentulous patients were provided with 95 osseointegrated titanium fixtures in 7 upper and 9 lower jaws. Facultatively removable bridges were later connected to abutments, attached to the fixtures. The marginal soft and hard tissue reactions were investigated at a baseline examination and after 6, 12, 21, 30 and 39 months by standardized clinical and radiographical methods. At the last examination, microbiological samples and gingival biopsies were also analysed. The % ratios of abutments without plaque, 70-75%, and without any gingivitis, 80-85%, were almost constant throughout the study. The mean probing depth was 2.9 mm at the final examination. About 75% of all probing depths were 3 mm or less and none exceeded 5 mm. The bridge-gingiva distances increased during the investigation. Attached gingiva surrounded 65% of the buccal and lingual abutment surfaces. Only 0.9 mm marginal bone was lost as a mean during the first year and not more than 0.05 mm annually for the next 2 years. After 6 months, no significant changes in marginal bone levels occurred. The perifixtural bone gradually became more radiopaque, especially marginally in upper jaws, indicating a successive load-related remodelling. The microbiotia comprised coccoid cells and non-motile rods to 93% in 32 samples. Healthy tissues were present in 35% of the 14 soft tissue biopsies. In a further 29%, only a slight inflammation was observed. No constant correlations could be established for any of the investigation parameters used. It is concluded that the marginal soft tissue reactions were mild and not significant for a progressive periodontitis. Mobility tests of separate fixtures combined with quantitative and qualitative standardized radiological examinations of the surrounding bone appear to provide a truer comprehension of longitudinal events at osseointegrated implants than conventional clinical soft tissue observations. The prognosis for the osseointegrated implants appears excellent, especially with regard to the microbiotia, the small marginal bone height changes, and the radiological indications of remodelling in the perifixtural bone.

Adult↗
PubMed1986

Marginal tissue reactions at osseointegrated titanium fixtures. (II) A cross-sectional retrospective study.

20 totally edentulous patients, provided with 24 facultatively removable fixed bridges (13 upper and 11 lower jaws) were recalled. The material consisted of 125 osseointegrated titanium fixtures with a mean observation time of 7.6 years (range 6 months to 15 years). The marginal tissues were examined by conventional periodontal clinical methods and standardised radiography. Microbiological samples and biopsies of the soft marginal barrier tissues were retrieved for dark-field and histological analysis, respectively. The percental ratios of abutment surfaces devoid of plaque and without signs of gingivitis, were 46% and 20%, respectively. In contrast to earlier studies, the presence of plaque and gingivitis was significantly correlated. This relationship was probably due to more plaque being present. The mean probing depth was 3.8 mm. In 40% of the measurements, the probing depths were 3 mm or less, and in 45% between 4 and 5 mm, whereas they only in 15% were 6 mm or more. They were greater in upper than in lower jaws and were found to be significantly correlated with gingivitis. Attached gingiva surrounded about 51% of the buccal and lingual abutment surfaces. The marginal bone height changes were very small during the follow-up period (0.07 mm annually). Coccoid cells and non-motile rods dominated the microflora to 94% in the 48 samples taken. Out of the 19 biopsies, 58% showed healthy mucosa and a further 37% had the lowest inflammation score. The indications of gingivitis and deep pockets at the clinical examination were not found accompanied by an accelerated marginal bone loss, nor by a microflora or histological changes indicative of periodontitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

The condition of the soft tissues at tooth and fixture abutments supporting fixed bridges. A microbiological and histological study.

In 10 partially edentulous patients provided with fixed bridgework supported by the combination of tooth and titanium fixture abutments, the condition of the soft tissues surrounding the abutments was examined. Sampling of supra- and subgingival plaque was performed from both teeth and fixtures. The samples were analyzed regarding the total bacterial counts, the relative distribution of bacterial morphotypes and the cultivable microflora. From each patient, soft tissue biopsies were obtained from 1 tooth and 1 fixture abutment, and the specimens were analyzed for the presence and extension of inflammatory cell infiltrates. The microbiological examination showed that the distribution of bacterial morphotypes in the supra- and subgingival plaque both at teeth and fixtures were similar, irrespective of localization and type of abutment. Nonmotile rods dominated the microflora, whereas spirochetes were either not detected or occurred in very low proportions. From the histological analysis, it was found that a majority of the soft tissue biopsies (75-80%) from both tooth and fixture sites contained only very small inflammatory cell infiltrates.

Adult↗
PubMed1985

Marginal tissue reactions at osseointegrated titanium fixtures.

A longitudinal prospective and a cross-sectional retrospective study were undertaken in order to investigate the marginal tissue reactions at osseointegrated titanium fixtures and their abutments, supporting fixed bridges. Conventional clinical periodontal examination methods were combined with a serial-identical radiography. At the termination of the studies samples were taken for microbiological and histological analyses. Altogether the reactions at 220 fixtures in 40 jaws were explored. The clinical parameters were not found correlated with the other examination methods. Only 0.9 mm marginal bone was lost as a mean during the first year and then not more than 0.05-0.07 mm as a mean annually for the follow-up years. A stress-related remodelling of the perifixtural bone was observed radiographically. The microbiotia in the gingival pockets was dominated by cocci and non-motile rods (94%), indicating a favourable composition if similar findings had been observed at teeth. Half the number of the biopsies had no inflammatory infiltrates and a further third had the lowest inflammatory score in a 3-grade scale. The results indicate that the soft tissue surrounding the gingival part of osseointegrated fixtures remains remarkably healthy, which, in combination with the annual minor loss of marginal bone, is an indication of good long-term clinical prognosis.

Alveolar Process↗
PubMed1985

Tissue integrated prostheses in clinical dentistry.

Implants can be anchored to bone either by a sheath of non-mineralized connective tissue or by osseointegration. The latter gives a firm, intimate and lasting connection. The requirements for osseointegration and the evidence that it occurs are reviewed together with its indications within dentistry. Treatment procedures with jaw-bone anchored bridges on osseointegrated implants are summarized. The series treated comprised about 6000 implants in 1000 jaws of 1000 patients. About 1500 implants were statistically analysed after observation times of 5-12 years. The longest observation period is presently 19 years. Only 14 patients had to revert to removable dentures. The masticatory function of the patients was restored to the same level as that of patients with natural dentitions of corresponding extent. Psycho-socially the patients were almost entirely relieved of their previous severe handicaps related to edentulousness. In all lower and 90 per cent of upper jaws the bridges were continuously stable. The marginal soft tissue reactions were mild and the marginal bone loss less than 1.0 mm during the first year and thereafter only 0.05-0.07 mm annually. After the first year hardly any implants were lost and almost no marginal bone. The implant survival rates were 84 and 93 per cent for those in upper and lower jaws respectively. These results allow a very predictable prognosis to be given for tissue integrated prostheses.

Adult↗