Search PubMed⌕ Search

Biomedical subjects

B Andersson

Publications and source records attributed to B Andersson.

629 records · Page 35Linked to original sources
PubMedDate not supplied

Rehabilitation of patients with severely resorbed maxillae by means of implants with or without bone grafts: a 3- to 5-year follow-up clinical report.

Forty three patients with severely resorbed maxillae who had been referred for implant treatment were assigned to 1 of 3 treatment options: bone grafting and implant placement (graft group), modified implant placement with no bone grafting (trial group), or optimized complete dentures (no-implant group). Sixteen, 20, and 7 patients, respectively, were assigned to the 3 groups. The patients have been examined annually, and at the time of this report they had been followed for 3 to 5 years after treatment. At the 1-year follow-up, 10% (22 of 221) of the implants had been lost, and at the 2-year follow-up, 18% of the implants had been lost (40 of 221; 25% in the graft and 13% in the trial group); after that time, no further losses occurred. Life table analysis showed cumulative success rates of 82% in the graft group and 96% in the trial group after 1 year, and 74% and 87%, respectively, at the final examination after 3 to 5 years. The failure rate was higher in smokers than in non-smokers. A substantial reduction of the grafted bone, especially of onlay grafts, occurred early after grafting surgery in many patients. Mean marginal peri-implant bone loss was 0.6 mm during the period from prosthesis connection to the 1-year follow-up, and from the 1-year to the 3-year follow-up, average peri-implant bone loss was 0.3 mm in the graft group and 0.5 mm in the trial group. The results corroborated previous findings that patients with severely resorbed maxillae have an increased risk of implant failure in comparison to patients with good bone quantity and quality. However, in this investigation, practically all implant losses occurred during the first 2 years, whereupon a steady state seemed to follow for up to 5 years after loading.

Aged↗
PubMedDate not supplied

Alumina ceramic implant abutments used for single-tooth replacement: a prospective 1- to 3-year multicenter study.

PURPOSE: The aim of the study was to compare results after 1 and 3 years when single crowns supported by CerAdapt (test) ceramic abutments or CeraOne (control) titanium abutments were loaded. MATERIALS AND METHODS: The material was divided into two groups: in group A, 69 (34 test, 35 control) abutments/crowns from all involved clinics were followed for 1 year; and in group B, 20 (10 test, 10 control) abutments/crowns from one of the clinics were followed for 3 years. RESULTS: No implant failed, giving a cumulative success rate of 100% for the implants. Two CerAdapt abutments in group A fractured, giving a cumulative success rate of 93% for the CerAdapt and 100% for the CeraOne abutments after 1 year. No abutment failed in group B, giving a cumulative success rate of 100% both for the CerAdapt and the CeraOne abutments between 1 and 3 years. The CerAdapt fractures might have been due to the fact that the abutments were impaired through too-extensive preparation and/or had been exposed to a too-high bending moment. Almost no marginal bone loss was recorded, indicating a stable bone situation both at CerAdapt and CeraOne abutments on single-tooth implants. Healthy conditions, with a relatively stable level of the periimplant mucosa in relation to the abutment/crown, were recorded for soft tissues both at CerAdapt and CeraOne abutments. Both clinicians and patients rated the esthetic result as excellent for practically all cases. CONCLUSION: The results demonstrate the esthetic possibilities and the safety of single-tooth replacement when accepted treatment concepts are followed and documented components are used. The tested abutments worked well, although the fractured CerAdapt abutments indicate that ceramic abutments are more sensitive to handling procedures than the titanium abutments.

Adolescent↗
PubMedDate not supplied

Procera AllCeram crowns followed for 5 to 10.5 years: a prospective clinical study.

PURPOSE: This is a report on Procera AllCeram crowns in a prospective multicenter study. The aim of the study was to evaluate AllCeram crowns in dental practice over a 5- to 10.5-year period. Some of the AllCeram crowns were among the very first that were placed. MATERIALS AND METHODS: The crowns were placed between 1989 and 1995. Twelve clinicians at nine clinics placed 87 crowns in 50 patients. The California Dental Association quality evaluation system was used for assessment of marginal integrity and esthetics. RESULTS: After 5 and 10 years a cumulative survival rate of 97.7% and 93.5%, respectively, and a cumulative success rate of 97.7% and 92.2%, respectively, was recorded. Six crowns (7%) were recorded as failures; five of these crowns (6%) had to be remade. The marginal integrity was considered excellent or acceptable for 92% of the crowns. Bleeding was somewhat more often recorded at teeth with AllCeram crowns (39%) than at contralateral teeth (27%). Endodontic treatment was performed for a low number (2%) of the AllCeram crowns. The patients found the esthetics to be excellent. CONCLUSION: The results of this study demonstrate about the same clinical outcome as has been reported by similar studies on all-ceramic crowns built on a core of alumina. The outcome is also in agreement with that reported for metal-ceramic crowns. The results indicate a good prognosis for Procera AllCeram crowns also for posterior teeth.

Adult↗
PubMedDate not supplied

Monocyte release and plasma levels of interleukin-6 in patients irradiated for cancer.

Interleukin-6 (IL-6) release from purified blood monocytes was determined in patients with breast cancer or prostatic cancer before and after radiation treatment (Rx). Plasma levels of IL-6 and neopterin were also determined. Spontaneous IL-6 release in vitro was higher in breast than in prostatic cancer or in controls. Strong lipopolysaccharide (LPS)-induced cellular IL-6 release was detected in breast cancer and controls but was subnormal in prostatic cancer. Addition of indomethacin to cultures had no effect on IL-6 release. Rx generally increased levels of in vitro released IL-6 and raised LPS-stimulated IL-6 secretion in prostatic cancer to normal. Plasma levels of IL-6 were lower in breast than in prostatic cancer or controls. Rx resulted in a tendency towards raised levels in both patient groups suggestive of monocyte activation. In accordance with this, plasma levels of neopterin, which were normal before treatment, increased in prostatic cancer patients after Rx. Taken together, the results of this study indicate that monocyte release as well as plasma levels of IL-6 are affected by the malignant state as well as by radiation treatment. In view of the antiproliferative effects of IL-6, the findings may have bearing on the pathogenesis and treatment of malignant disease.

Adult↗
PubMedDate not supplied

Assessment of digital chest radiography using stimulable phosphor.

In this pilot study, conventional and digital radiography of the chest was compared in 170 patients. Two digitized radiographs, one frequency modified and one simulating the conventional film-screen combination, and the conventional films were reviewed independently by 5 radiologists with different experience. In spite of the smaller size and lower spatial resolution of the digitized compared with the conventional radiograph, only slight differences were revealed in the observation of different pulmonary and mediastinal changes. Digitized radiography is therefore considered suitable for chest examinations.

Adolescent↗
PubMedDate not supplied

In vitro cultivation of leprosy bacilli on hyaluronic acid based medium. 1. Preliminary report.

In vitro cultivation is reported of Mycobacterium leprae on a medium (designated LA-3) based on hyaluronic acid with additional ingredients of yeast extract, bovine albumin and glycerin together with phosphate buffer. The medium is also incorporated with agar or agarose (designated LA-3P) to serve as culture plates. Initial growth in LA-3 in test tubes required about six weeks but subsequently this was speeded up to about two weeks utilizing large quantities of media with aeration by shaking twice a day. Growth on LA-3P yields numerous small orange-yellow colonies in two to three weeks. Facets of the emerging aspects of the life cycle of M. leprae under cultivation are given preliminary report. The bases for the allegation of M. leprae identity of the cultured bacilli are essentially the following six determinations. 1. Pathologic and experimental determined rationale for the essential M. leprae nutrient requirement. 2. Several cultures having the same characteristics have been isolated from LL patients widely separate in time and by geography. 3. Failure of culture isolates to subculture on the usual media employed in the cultivation of mycobacteria at both 37 degrees C and room temperature. 4. 1 degree cultures in liquid medium successfully transferred to 2 degrees liquid medium and to 2 degrees agar medium plates. 5. Bacillary isolates and bacilli of 1 degree and 2 degrees liquid medium cultures all stain with pooled LL serum, FITC coupled, M. leprae specific antibody with which a broad range of other mycobacteria do not react. 6. M. lepraemurium also presents good growth on this medium.

Adult↗
PubMedDate not supplied

Single-tooth restorations supported by osseointegrated implants: results and experiences from a prospective study after 2 to 3 years.

Fifty-seven patients were followed for 2 years and 34 patients for 3 years in a study of the CeraOne system. One implant was lost, resulting in a cumulative success rate of 97.3% at the 3-year examination. All-ceramic crowns were seated for 95% of the subjects, and only four of the crowns were classified as failures. Two all-ceramic crowns fractured following trauma, but no crown was fractured when exposed to common bite forces. The bone loss around implants and adjacent teeth was small, and few problems were observed. It was proven that the system achieves good esthetic results and avoids the complications of screw loosening and fistula formation.

Adolescent↗
PubMedDate not supplied

Prognosis of alternative therapies in patients with heart failure not accepted for heart transplantation.

BACKGROUND AND METHODS: This article describes the outcome of alternative therapies in patients with end-stage heart failure, New York Heart Association class III-IV, referred for heart transplantation evaluation but not accepted for the procedure. From January 1988 through September 1992, 233 consecutive patients with severe heart failure were admitted to the thoracic transplantation center at Sahlgrenska University Hospital. At the time of admission all patients received standard medical treatment for heart failure. During the pretransplantation evaluation, an attempt to optimize the medical therapy was made in all patients. RESULTS: Eighteen patients (8%) died before a decision concerning transplantation was made, and 146 patients (63%) were accepted for heart transplantation. There were 69 patients (30%) who were denied heart transplantation for various reasons, and they were subgrouped: patients with contraindications (group 1, n = 23) or without indication (group 2, n = 10) for heart transplantation, patients with a positive response to intensified medical therapy (group 3, n = 25), and patients who underwent coronary artery bypass grafting and/or valvular heart surgery (group 4, n = 11). The 1-, 3-, and 5-year actuarial survival rates were as follows: group 1, 26%, 16%, and 8%; group 2, 100%, 77%, and 39%; group 3, 96%, 67%, and 53%; and group 4, 64%, 36%, and 27%, respectively. The corresponding figures for patients who had a heart transplantation were 85%, 79%, and 75%, respectively. During the first 2 to 3 years of follow-up the survival of group 2 and group 3 patients was similar to that of patients who underwent transplantation. However, late survival was worse compared with the heart transplant group. CONCLUSIONS: These results suggest that by close follow-up it may be possible to postpone heart transplantation in a selected group of patients.

Adult↗
PubMedDate not supplied

Bone tissue response to commercially pure titanium implants blasted with fine and coarse particles of aluminum oxide.

The present study compares the bone response to commercially pure titanium screws with two different degrees of surface roughness. Implants blasted with 25- and 250-micron particles of aluminum oxide were placed in rabbit tibiae after the surface roughness of the implants had been measured. After 4 weeks, there was a significantly higher bone-to-metal contact for implants blasted with 25-micron particles compared to those blasted with 250-micron particles. The present study indicates that a highly increased surface roughness compared to a moderately increased one is a short-term disadvantage for bone tissue.

Aluminum Oxide↗
PubMedDate not supplied

A 1-year follow-up of implants of differing surface roughness placed in rabbit bone.

Screw-shaped implants were prepared with three different surface topographies: One was left as machined, ie, a turned surface, and two were blasted surfaces with differing degrees of surface roughness. The surface topography was measured with a confocal laser scanning profilometer and the surface roughness was characterized using height and spatial descriptive parameters. The turned surface had an average surface roughness of 0.96 micron and an average peak spacing of 8.6 microns. The two blasted surfaces had surface roughness values of 1.16 microns and 1.94 microns, respectively; the corresponding values for the peak spacing parameter were 10.00 microns and 13.22 microns, respectively. After 1 year in rabbit bone, the bone response to the turned implants was compared with the response to the two blasted implant surfaces. Firmer bone fixation was found for the two blasted surfaces, with statistically significant increases in removal torque and percentage of bone-to-metal contact. Furthermore, about 2 mm from the implant surface, the titanium release was similar for the turned and the 25-micron aluminum oxide-blasted implants.

Aluminum Oxide↗
PubMedDate not supplied

Rehabilitation of patients with severely resorbed maxillae by means of implants with or without bone grafts. A 1-year follow-up study.

Forty-three patients with severely resorbed maxillae who had been referred for implant treatment were assigned to one of three treatment groups: bone grafting and implant placement (graft group); modified implant placement but no bone grafting (trial group); or optimized complete dentures (no-implant group). Sixteen, 20, and 7 patients, respectively, were assigned to the three groups. At the 1-year follow-up, 10% of the implants had been lost. Only a few of the failures (3/22) occurred after prosthesis placement. The cumulative success rates were 83% in the graft group and 96% in the trial group. A substantial reduction of the grafted bone, especially of the onlay grafts, occurred in many patients. During the period from prosthesis connection to the 1-year follow-up, marginal peri-implant bone loss was on average 0.5 mm. Despite the often demanding procedures involved, all but one patient in each implant group said that they would undergo the treatment again. Most patients were very satisfied with the treatment outcome and their improved masticatory ability. Those who had renounced implant treatment appeared modestly adapted to their optimized dentures, but reported retention problems and less satisfaction with mastication.

Adult↗
PubMedDate not supplied

Cemented single crowns on osseointegrated implants after 5 years: results from a prospective study on CeraOne.

PURPOSE: The aim of this prospective study was to present the results after 5 years of loading of 65 CeraOne (Nobel Biocare) crowns. MATERIALS AND METHODS: Sixty-two implants in the maxilla and 3 implants in the mandible were placed in 57 patients. Sixty-two all-ceramic and three metal-ceramic crowns were cemented. The group comprised the first patients treated with the CeraOne prosthodontic concept. RESULTS: Eight patients did not complete the study. Only one implant failed, giving a cumulative success rate for implants of 98.5%. The failed implant was replaced: a crown was cemented and then followed for 5 years without any complications. Four crowns were recorded as failures, giving a cumulative success rate for crowns of 93.7%. It should be observed that this result was very positive, as all crown failures were related to extraordinary causes and not one was a result of common bite forces or fatigue. The initial bone loss was in accordance with other studies on Brånemark implants, and a stable situation was recorded after 2 years for the supporting bone around implants and adjacent teeth when the conical implants were excluded. Soft tissues around implants and adjacent teeth appeared healthy, and the cementation and the placement of the abutment shoulder in the peri-implant sulcus did not cause any recession of the peri-implant mucosa. CONCLUSION: CeraOne experienced virtually no complications and proved to be a highly predictable and safe prosthodontic concept. CeraOne also eliminated problems with abutment screw loosening and created a platform for good esthetic results and satisfied patients.

Adult↗
PubMedDate not supplied

Five-year prospective study of prosthodontic and surgical single-tooth implant treatment in general practices and at a specialist clinic.

PURPOSE: The aim of this 5-year prospective study was to compare the results of single-tooth implant treatments planned and performed at four general practitioners' offices with the results from a specialist clinic. MATERIALS AND METHODS: The group comprised 38 patients. Nineteen patients, with 19 implants/crowns, were planned and treated by four general practitioners, and the outcome was compared to a matched group of patients from a specialist clinic. RESULTS: Three patients did not complete the study. None of the implants failed; one crown failed. This was a very positive result, as the single failure, a crown at the specialist clinic, was caused by an extraordinary trauma and was not related to a common cause such as bite forces or fatigue. No significant differences were observed between the groups when the radiographic findings were compared. Some minor differences, for bleeding and the position of the mucosal level around implants and adjacent teeth, were observed between the two groups. CONCLUSION: The small discrepancies that were observed between treatment performed by the four general practitioners at their own offices and treatment performed at the specialist clinic were not regarded to be of any clinical importance. This indicates that complete single-tooth implant treatment may be performed for many patients by general practitioners who have received adequate training, allowing the possibility of referring complicated treatments to specialists and other treatments to general practitioners.

Adult↗