摘要:

The purpose of this review is to evaluate the effects of the biomechanical aspects of dental implant design on the quality and strength of osseointegration, the bone–implant interface, and their relationships to the long-term success of dental implants. The engineering design of implants is based on many interrelated factors, including the geometry of the implant, mechanical properties, and the initial and long-term stability of the implant–tissue interface. There is no one “optimal” design criterion. However, implants can be engineered to maximize strength, interfacial stability, and load transfer by using different materials, surfaces, and thread designs. Limited information is currently available in addressing how implant thread design influences the overall implant success. Therefore, this article reviews and discusses design elements of various dental implant systems currently in use as they affect the quality of osseointegration and their relationship to overall long-term success patterns.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PepGen P-15 is a combination natural anorganic bovine-derived hydroxyapatite matrix (ABM) coupled with a synthetic cell-binding peptide (P-15). This material has been reported to enhance bone formation in periodontal osseous defects. The aim of this study was to assess the effect of ABM/P-15 on the healing of cortical bone defects in rabbits. Five New Zealand rabbits were used. Two 8-mm bone defects were created in each tibia. Eight defects were filled with PepGen P-15, 8 defects with PepGen P-15 Flow, and 4 defects were used as a control group. A total of 20 defects were created. All rabbits were killed at 4 weeks. Block sections containing the defects were retrieved and the specimens processed for light microscopy examination. Newly formed bone was present in both test groups, whereas, in the controlgroup, only a scarce quantity of newly formed bone was present and the cortical defects had not been filled by the regenerated bone. Statistical evaluation showed that there were statistically significant differences between control sites and sites treated with P-15 and P-15 Flow (P= 0.0001), and also between sites treated with P-15 and P-15 Flow (P= 0.0001), respectively. No acute inflammatory infiltrate cells were visible in both of these groups. Both PepGen P-15 and PepGen P-15 Flow enhanced new bone formation in the cortical drilled defects, whereas control defects showed very little newly formed bone.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

To solve some of the problems inherent in bone regeneration, various types of graft materials, matrix, putty, and gel delivery systems have been developed. These deliver demineralized bone matrix (DBM) to a graft site and maintain it in an appropriate position to achieve favorable results. This prospective study reviewed 10 cases of extraction immediate grafting with a putty–DBM delivery system. Five patients were male and 5 female. At intervals ranging from 4 to 21 months postextraction grafting, bone cores were harvested at the time of surgical insertion of Replace endosteal two-stage implants. All patients were restored with single-tooth self-standing prostheses. Bone quality and quantity in each of the bone cores were evaluated. All 10 cases were completed with favorable outcomes.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The oral rehabilitation by dental implants in patients with diabetes remains a controversial issue. The aim of this study was to evaluate the influence of diabetes mellitus and insulin therapy on the bone healing around dental implants using torque removal. Twenty-seven rabbits were randomly divided into 3 groups with 9 animals each: control (C) group, induced diabetic (D) group, and insulin-treated diabetic (ITD) group (10 U/day). After 1 week, one implant was inserted at the tibial metaphysis of the animals. The glucose levels were periodically evaluated through the glucose–oxidase enzymatic method. The animals were killed at 4, 8, and 12 weeks after surgery and the biomechanical test was performed using a torque manometer. Statistically significant differences regarding the removal torque of the implant could not be found at 4 weeks (P= 0.2) among groups. Group C showed statistically higher values than groups D and ITD at the experimental periods of 8 (P= 0.0001 andP= 0.0002, respectively) and 12 weeks (P= 0.0053 andP= 0.001, respectively). There were no statistical differences between D and ITD groups in any of the experimental periods. Diabetes mellitus has negatively influenced the mechanical retention of implants placed at the tibial metaphysis of rabbits. Therapy with insulin did not induce any changes.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The purpose of this study was to evaluate the influence of an estrogen-deficient state on bone around titanium implants placed in rats. Thirty female Wistar rats were divided into 2 groups: test (n = 15), ovariectomized rats (OVX); and control (n = 15), sham-operated rats. Screw-type titanium implants were placed bilaterally in rats 21 days after ovariectomy or sham surgery. After 60 days, the animals were killed and undecalcified sections obtained. Blood samples were collected to obtain serum levels of alkaline phosphatase at the time of killing. Bone-to-implant contact (BIC), bone area (BA) around the implants, and bone density (BD) in a 500 &mgr;m-wide zone lateral to the implant were obtained and arranged separately for the cortical (zone A) and cancellous (zone B) regions. In zone A, there was no significant difference between test and control groups regarding BIC and BD (P>0.05). A lower BA was observed in the estrogen-deficient animals (P<0.05). In zone B, data analysis showed that estrogen deficiency could result in a lower percentage of BIC, BA, and BD (P<0.05). In addition, a higher concentration of alkaline phosphatase was observed for the test group. An estrogen-deficient state could affect bone healing and bone density around titanium implants placed in rats, especially in the cancellous bone area.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID