摘要:

Placement of endosseous implants and inferior alveolar nerve transposition is a treatment option for patients with an edentulous posterior mandible with inadequate bone height superior to the inferior alveolar canal. Complications associated with these procedures include infection, prolonged neurosensory disturbances, and/or pathologicfracture. This report presents the surgical management of a patient with a mandible fracture after inferior alveolar nerve transposition with concurrent placement of two endosseous implants.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Autogenous block bone grafts have been highly successful in treating human periodontal defects, restoring esthetics, and developing adequate bone volume for dental implant placement. Limitations in available donor bone, the need for an added surgical procedure, and other potential complications have made the use of allogenic bone graft materials an important alternative. One patient described in this report presented with fractured root syndrome of the right maxillary incisor with severe resorption of the buccal plate. After atraumatic tooth extraction, a staged treatment approach involving localized ridge augmentation with an allogenic iliac bone block material and dental implant placement was used. The host bone completely incorporated the graft with only minor resorption, which enabled the implant to be placed. The allogenic bone block material used in this study was an effective alternative to harvesting and grafting autogenous bone for implant site development. The cases presented in this article clinically demonstrate the efficacy of using a block allograft in generating effective new bone fill for dental implant placement.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The healing period between implant insertion and exposure is often challenging for both the patient and the surgeon. The use of a removable dental prosthesis is not recommended for a period of several days to 2 weeks in an effort to avoid undue pressure being placed on the newly placed implants and on the surrounding soft tissues. However, patients are frequently uneasy without dentures, even for a short period of time, because their diet and appearance are compromised. A simple technique was developed to overcome these obstacles. This technique allows the surgeon to place an im- mediate implant-supported prosthesis, based on two transitional implants, in addition to the implants placed for final restoration. This technique is performed at the surgical stage simultaneously with the placement of the permanent implants. It requires minimal additional time, and makes use of the patient’s original prosthesis as an interim removable restoration during the integration period.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The unitized (one-piece) dowel-crown technique described in this article uses routine clinical and laboratory procedures, minimizes clinical appointments, and provides asimplified prosthetic restoration for a single dental implant.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeThe aim of this study was to histologically evaluate the crestal bone response to loaded and unloaded implants in beagle dogs.Materials and MethodsSandblasted and acid-etched implants (Bone System, Milano, Italy) were placed in the mandible of six beagle dogs. The two premolars and the first molars had been extracted 3 months previously. Each dog received 12 implants in the mandible, and a total of 72 implants were used in this study. Three months after implantation, second-stage surgeries were performed for placement of abutments or healing screws. Three dogs were killed after 6 months, and three dogs were killed after 12 months. All 72 implants were re- trieved.ResultsNo statistically significant differences were found in the amount of bone loss between test and control implants, both at 6 and 12 months. Statistically significant differences were found, in both groups, between the bone loss observed at 6 months and that found at 12 months.ConclusionLoading does not seem to be a relevant factor in the peri-implant bone resorption observed during the first year of function. Our results support previous findings that bone crest level changes could depend on the location of the microgap.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Background and PurposeClinical and experimental studies show, with few exceptions, that type 1 diabetes mellitus is associated with a delay in bone repair around endosseous implants. The effect of insulin in bone repair/remodeling is not completely understood. The aim of this study was to investigate the course of histological and ultrastructural changes of the osseointegration process under the influence of insulin.Materials and MethodsTitanium implants were inserted into the tibiae of male Wistar rats. Animals were divided into three groups: 1) rats with alloxan-induced diabetes; 2) diabetic rats treated with isophane insulin (2 IU/day); and 3) matching controls. Histological and histomorphometric analysis of bone-implant sections were performed 10 and 21 days after implant placement.ResultsRelative to control values, rats with alloxan-induced diabetes exhibited a 50% reduction in the area of formed bone (P< 0.001) and in the surface of contact between bone and implant (P< 0.01) 21 days after implant placement. There were no significant differences between groups 10 days after surgery. Values returned to normal levels in diabetic rats after insulin treatment. Presence of chondrocytelike cells surrounded by a cartilaginouslike matrix in diabetic rats suggests a delay in the process of bone repair. Ultrastructural characteristics of bone-implant interface in diabetic rats treated with insulin resembled those observed in controls.ConclusionThe data presented suggest that bone repair around endosseous implants is regulated, at least in part, by insulin. The results imply that the control of the metabolic status of the diabetic patient is essential for a successful osseointegration.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeThe aim of the study was to radiographically measure the bone density at the peri-implant region after osseointegration and to compare the relative bone density achieved by different surface-treated implants.Materials and MethodsFour different types of implant surfaces were compared, using five young-adult male mongrel dogs. The first, second, third, and fourth lower premolars were extracted. Ninety days after removal, four 3.75-mm diameter and 10-mm long screw implants (Paragon) were placed with different surface treatments in the lower hemiarches. The dogs received two implants each of the following surface treatments: 1) smooth (machined); 2) titanium plasma spray; 3) hydroxyapatite coating; and 4) sandblasting with soluble particles. The implants were maintained unloaded for 90 days. After this period, the animals were killed and the hemimandibles were extracted and radiographed. The grey level of the bone adjacent to implants was measured with a specific software tool (line histogram) and the relative bone density was calculated.ResultsThe four different surface treatments promote different numeric levels of bone density around the dental implants (sandblasting with soluble particles, 52.45 ± 2.95; titanium plasma spray, 53.98 ± 3.67; machined, 55.78 ± 3.06, and hydroxyapatite coating, 58.2 ± 2.71). Therefore, the implants can be ranked in terms of relative bone density from high to low as follows: sandblasting with soluble particles, titanium plasma spray, machined, and hydroxyapatite coating. There were no statistically significant differences in bone density among the four groups (P= 0.1130, analysis of variance).ConclusionSurface treatments that add roughness to the implant show numerically higher bone density when compared with machined surfaces. The findings of radiographic density analysis suggest that the soluble blasting media–treated surface provides a greater bone density at the peri-implant region.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeThe importance of the soft tissue–implant interface is enhanced by the presence of a microgap between the implant and the abutment, which represents a contamination site for bacteria. The aim of this study was to investigate the interface between the Ankylos gap-free implant system and the surrounding soft tissues in a dog model.Materials and MethodsSix Labrador dogs were included in the study and two Ankylos implants were inserted per dog. The dogs were killed 6 months after abutment placement without functional loading and without plaque control. The implants were analysed histologically by scanning electron microscopy, light microscopy, and histomorphometry.ResultsSome sections exhibited histologic signs of a mild inflammation. The connective tissue between the most apical epithelial cells of the junctional epithelium and the alveolar crest was characterized by collagen fibers running from the periosteum and the alveolar crest toward the oral epithelium and, in front of the cone-shaped abutment, by a narrow zone of extracellular matrix with a few collagen fibers.ConclusionCompared with results obtained in other studies using different types of implant (Astra, Bränemark, ITI), the Ankylos implant showed a higher length and a larger width of connective tissue contact as well as a shorter epithelial downgrowth. The absence of a microgap in the Ankylos system could explain the histologic mild inflammation in the connective tissue.

ISSN:1056-6163    

出版商:OVID    

年代:2003

数据来源: OVID