摘要:

A platelet concentrate, when combined with calcified thrombin, produces a platelet gel that has been used to achieve hemostasis and modulate bone growth and wound healing. The recovery of high concentrations of viable platelets and their resulting growth factor levels represents the most important factor in the clinical utility of a platelet concentrate because only functional platelets can release the growth factors that are necessary to induce tissue growth and bone regeneration. The SmartPReP system’s efficiency in recovery of platelets from a sample of whole blood averaged 70.6%, almost twice that of various manual techniques using laboratory centrifuges. Platelet concentrates prepared by the SmartPReP system had a viability equal to platelet concentrates prepared for transfusion as measured by hypotonic stress, platelet aggregation, and p-selectin. A series of clinical case studies demonstrates the use of autologous platelet gel in oral surgery.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Preoperative radiographic assessment is mandatory for the meticulous treatment planning and successful placement of implants. The precise topographical evaluation of selected implant sites, apart from the most straightforward cases, requires tomographic examination with the use of diagnostic radiographic templates. The incorporation of various radiopaque materials such as barium sulphate and lead foil as radiographic markers had not been entirely satisfactory. A new contrast medium, Lipiodol ethiodized oil (Laboratoire Guerbet, Paris, France), can easily be mixed with the monomer of autopolymerizing acrylic resin. The resultant acrylic template has several advantages. The tomographic images (Scanora; Soredex Orion Corporation, Helsinki, Finland) are radiographically homogenous and show the contour of the future prosthesis, the angulation of the planned implant, and the thickness of the soft tissue. In addition, the radiopaque template is optically transparent (with a slight yellow tint), which facilitates good visibility of surgical sites when the template is modified to become the surgical guide for implant placement. This transparent template can be further modified for implant position registration at the time of surgery. Because this multipurpose template is simple to construct and inexpensive, it can be recommended for routine use in implant dentistry.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The implant periapical lesion (IPL), a possible cause for implant failure, may occur from the presence of pre-existing microbial pathology such as endodontic/periodontal lesions. This case report presents a case history related to IPL, which was caused by a pre-existing endodontic lesion. In addition, other possible causes such as surgical trauma and the management strategies of IPL are suggested. For the treatment of the infected form of IPL, a sequential surgical therapy can be utilized. This includes surgical removal of the implant or implant apical region, thorough debridement of the infected lesion, systemic antibiotics, and/or guided bone regeneration. The implant therapy should be directed to minimize the occurrence or consequences of IPL by careful diagnosis, systematic treatment planning, and appropriate treatment procedures.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeThe purpose of this report is to present a reliable surgical and prosthodontic protocol for the treatment of the atrophic maxilla by placing four zygomatic implants.Materials and MethodsThe surgical and prosthodontic procedures are described for the retreatment of a 63-year-old woman who had previously undergone an iliac crest bone graft transplant, which had resorbed.ResultsIt is possible to place double zygomatic implants bilaterally, in addition to conventional implants in the anterior maxilla. Bone grafting procedures can be avoided, resulting in a fixed implant-supported maxillary prosthesis.ConclusionA logical treatment solution is four zygomatic implants for the atrophic maxilla, especially because the previous iliac crest bone graft had resorbed.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

In this study,in vitroosteoblast responses to glow-discharged, commercially pure titanium (Ti) surfaces were investigated. It was hypothesized that the glow-discharge treatment would be an effective sterilization procedure for Ti implantations before implantation. The Ti surfaces were prepared by grinding to 600 grits followed by cleaning. These were then divided into two groups, with one group being the control and the other group undergoing glow-discharge treatment using oxygen. Human embryonic palatal mesenchyme cells, an osteoblast precursor, were used to evaluate the cell responses to glow-discharged and control Ti surfaces. It was observed from this study that protein production and osteocalcin production on both surfaces exhibited no significant differences during the 10-day study. Similarly, no significant differences were observed for alkaline phosphatase (ALP) specific activity during the first 7 days of incubation. However, at day 10, the ALP specific activity for control Ti surfaces was significantly higher than the ALP activity for the glow-discharged surface. Overall, this study suggested that the use of glow discharge as an alternative sterilization procedure for medical and dental implants did not inhibit osteoblast phenotypic expression.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

During the past 10 years, clinicians have used two-piece implants as a one-piece system for immediate loading to accomplish early recovery for function and esthetics. The statistical analysis by the Institute of Clinical Materials demonstrates high survival rates of 92.3 ± 8.3%. Animal experiments of beagle dogs have been carried out to analyze successful conditions of immediate loading according to the dependency of bone formation–resorption upon the biomechanical stress–strain of bone. Histometric investigations clarified that the micromotion of less than 30 &mgr;m at the implant–bone interface did not interfere with the osteogenesis and new bone growth at the implant–bone interface. Bone formation and resorption are discussed from the standpoint of minimum effective strain on living bone.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeThe purpose of this study was to compare bone-to-implant contact (BIC) of the one-stage sandblasted surface EVL implant (SERF, Decines, France) with that of the two-stage turned (machined) Branemark Nobel BioCare implant in a dog model system.Materials and MethodsThree 1-year old female beagle dogs (canine) were acquired, examined, and quarantined. In dog no. 1, three test implants were placed on one side of the jaw, and four control implants were placed on the other side. In dog no. 2, two test implants were placed in alternation with two control implants on the left and right sides (total 4 tests, 4 controls). In dog no. 3, three test implants were placed on one side and three control implants on the other. After a 3-month period of healing, the dogs were killed and the jaws sectioned for histological preparation. Eleven implants, six tests, and five controls were available for histological evaluation.ResultsThe percent of BIC for the test implants varied from 24.9% to 61.6%, with an average of 42.7%. The percent of BIC for the control implants varied from 22.1% to 42.6%, with an average of 27.4%.ConclusionThe degree of BIC of the EVL implants was on average greater than that of the turned surface of the Branemark implant. However, because of the limited number of implants placed in this pilot study, the results should be interpreted with caution.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose:The aim of this study was to evaluate, histologically and quantitatively, the presence of macrophages loaded with metallic particles in the periimplant soft tissues of failed titanium (Ti) dental implants.Materials and Methods:The study was performed on sections of metallic Ti implants embedded in methyl methacrylate resin that exhibited macrophages in the soft tissues contiguous with the implant. The volume of periimplant soft tissue was evaluated, and the number of macrophages was determined. The particles within macrophages were analyzed by energy-dispersive x-ray analysis.Results:Macrophages were more abundant in the zone adjacent to the metallic implant as compared with the zone further away from the implant. Energy-dispersive x-ray analysis revealed the presence of Ti within macrophages.Conclusions:Macrophages loaded with Ti particles can be associated with a corrosion process. The method proposed would allow for the objective evaluation of the presence of macrophages associated with dental implants and other orthopedic materials that contain Ti or other metals.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose:To evaluate the number and morphology of fibroblasts grown on machined titanium healing abutments treated with an air-powder system.Materials and Methods:Twenty-six abutments were assigned to two experimental groups: control (no treatment) and treated (exposed to the Prophy-Jet for 30 seconds). The specimens were incubated for 24 hours with fibroblastic cells in multiwell plates, followed by routine laboratory processing for scanning electron microscope analysis. The specimens were photographed at ×350, and the cell number was counted on an area of approximately 200 um2.Results:No significant differences were found on morphology between the groups (P> 0.05); however, the control group presented a significantly greater amount of cells (71.44 ± 31.93, mean ± SD) in comparison with treated group (35.31 ± 28.14), as indicated by a nonpairedttest (P= 0.001).Conclusion:The use of an air-abrasive prophylaxis system on the surface of titanium healing abutments reduced the cells proliferation but did not influence cell morphology.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeA frequently cited cause of dental implant failure is the inadequate quality of bone found at the implant site during osteotomy preparation. Although bone quality clearly can affect integration rates, additional variables, such as the implant surface conditioning, can also influence long-term implant performance success. The following report examines outcomes of clinical studies that monitored the performance of machined-surfaced implants and dual acid-etched Osseotite (Implant Innovations, Inc., Palm Beach Gardens, FL) implants isolating the effect of bone quality and implant surface conditioning.Materials and MethodsImplant data are derived from eight prospective multicenter clinical studies representing 2614 machined-surfaced implants and 2288 Osseotite implants. All implant placement surgeries followed a two-stage surgical approach with an unloaded healing period of 4 to 6 months. Bone quality was assessed by operator perception of resistance during drilling and ranked as dense, normal, or soft. At the time of this analysis, implant follow-up from placement ranged up to 66 months for the Osseotite and 84 months for the machined-surfaced implants. To isolate the effect of bone quality,other baseline variables were compared to ensure equal distribution between groups. Baseline variables included patient demographics, locations, dimensions of implants, and types of restorative cases. Implant performance was analyzed using nonparametric survival analysis (Kaplan-Meier estimator). Cumulative success rates (CSR) were calculated and differences between implant-bone quality combinations were assessed using the log-rank method.ResultsFor the machined-surfaced implants, the 4-year CSR in all bone sites is 92.7%. For the implants placed in good (dense and normal) bone, the 4-year CSR is 93.6% compared with the 4-year CSR in poor (soft) bone of 88.2% (P< 0.05). For Osseotite implants in all sites, their overall 4-year CSR was 98.4%, 98.4% in good bone, and 98.1% in poor bone.ConclusionsBone quality therefore seems to have a definitive impact on machined-surfaced implants, but this effect was not observed in the Osseotite implant series.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID