Ten-year results for Br?nemark implants immediately loaded with fixed prostheses at implant placement

This investigation was initiated to develop a method to provide patients with a fixed provisional prosthesis placed at the time of implant placement. Sixty-three standard 3.75-mm Nobel Biocare implants of varying lengths were placed into mandibular sites in 10 patients and followed for up to 10 years. Twenty-eight implants were immediately loaded at implant placement, providing support for fixed provisional prostheses, while 35 adjacent implants were allowed to heal submerged and stress-free. Following a 3-month healing period, the submerged implants were exposed and definitive reconstruction was accomplished. All 10 prostheses supported by 28 implants placed into immediate function at the time of implant placement were successful during the 3-month healing period. Of these 28 implants placed into immediate function, 4 ultimately failed. Of the 35 submerged implants, all are osseointegrated and in function to date. Life-table analysis demonstrates an overall 10-year survival rate of 93.4% for all implants. The 10-year life-table analysis of survival is 84.7% for immediately loaded implants and 100% for submerged implants. Statistical analysis of the submerged versus immediately loaded implants demonstrates failure rates for immediately loaded implants to be significantly higher (P = .022 by the log rank test). These data demonstrate that although mandibular implants can be successfully placed into immediate function in the short term to support fixed provisional prostheses, long-term prognosis is guarded for those implants placed into immediate function distal to the incisor region.     

The use of transitional implants for immediate fixed temporary prostheses in cases of implant restorations

While the original Br?nemark implant protocol has continued to evolve, the avoidance of implant loading during osseointegration remains a prerequisite with all implant systems. Immediately loaded transitional implants have recently been developed to support the fabrication of a fixed provisional prosthesis that provides implant patients with improved aesthetics and function during the osseointegration period. In this manner, osseointegration can occur free from prosthetic and transmucosal loads. This article describes the use of transitional implants and presents a classification of three different case types.     

Implant-supported overdenture therapy: a retrospective study

All patients (n = 46) treated with implant-supported overdentures at the Department of Prosthetic Dentistry, Dental and Medical Health Centre, Halmstad, Sweden, from 1986 to 1993 were studied. The clinical examination was completed in 1994. The material was divided into two subgroups: Group A had been initially treatment planned for an implant-supported overdenture, and Group B had been planned for fixed prostheses but because of loss of implants before loading, treatment with a fixed prosthesis was not possible. The authors present their experience and patient reactions to overdenture therapy in two defined groups of patients. The implant failure rate before loading for Group A (n = 12) was 15% (six implants out of 39), and the rate before loading for Group B (n = 29) was 43.6% (68 implants out of 156). After prosthodontic treatment in Group A, the implant success rate after loading was 87.9%, and the overdenture stability was 84.6%. In group B, 17 implants placed in the maxillae were lost after overdenture therapy, which resulted in an implant success rate of 79.3%. A total of eight overdentures, all of which had been placed in the maxillae, were lost, resulting in an overdenture stability of 73.3%. In this study "change of retentive clips" was the predominant prosthodontic complication related to the overdentures, especially in Group B. Most of these complications (62%) occurred in patients with clinical signs of bruxism. Patient reactions to treatment with an overdenture were positive regarding esthetics for both groups. More negative views were recorded in Group B than in Group A in response to function and retention of the overdenture.     

The dark side of dioxygen biochemistry

The aim of this study was to evaluate the clinical function and long-term prognosis of overdentures retained by a small number of implants in the maxilla and mandible using one of two different attachment systems. Included in the study were all patients referred to specialty clinics in J?nk?ping and Link?ping, Sweden, during the treatment period who needed an overdenture and could be provided with a minimum number of two bilaterally-placed implants. Excluded were patients with bone-grafted jaws, irradiated cancer patients, heavy bruxers, and patients who had lost a fixed prosthesis because of implant losses. The patients were randomly assigned to receive one retentive system, either a round 2-mm-diameter bar with clips or ball attachments (Nobel Biocare). Eighteen overdentures were placed in maxillae and 32 in mandibles, supported by a total of 115 Br?nemark implants. Of the implants placed, 86.1% were continuously osseointegrated. The cumulative implant survival rates after 7 years of loading were 75.4% in the maxillae and 100% in the mandibles. There was no difference in implant survival rate between the attachment systems. Patients with implant losses were characterized by severely resorbed maxillary ridges and inferior bone quality, together with unfavorable loading circumstances such as short implants combined with long leverages. Complications and prosthetic adjustments were mostly resolved early and easily.     

Impairment, disability, and handicap in multiple sclerosis. A cross-sectional study in an incident cohort in M?re and Romsdal County, Norway

Non-submerged ITI Bonefit implants (ITI Dental Implant System) were inserted in edentulous lower jaws of 46 patients. The patients were provided with either a fixed prosthesis or an overdenture, and has been followed during a 2-year-period. At the 1-year examination, the suprastructures were removed permitting test of the individual implant stability. Radiographic examinations were performed in connection with the loading of the implants and at the 1-year examination. In total 216 implants were inserted. 4 implants were lost before loading and 4 during the 2nd year of function, which gives a survival rate after 1 year 98% and after 2 years of 96%. The mean marginal bone loss during the first year of function was 0.1 mm. However, the marginal bone changes had a high degree of variation and four implants showed a severe bone loss. The intention is to follow this patient group with annual examinations during 5 years.     

Biomechanical considerations when combining tooth-supported and implant-supported prostheses

The force distribution of multiple tooth-supported and implant-supported prostheses is completely different. A direct correlation exists between the degree of flexion at the site of loading and the amount of force distribution to other members of the prosthesis. Micromovement produced by the periodontal fibers facilitates force distribution to all the root surfaces of the natural tooth abutments. The rigidity of the implant/abutment/prosthesis configuration concentrates the force at the crestal bone at the site of loading with limited distribution to the remaining implants. Differential mobility concentrates the force distribution to the bone support of the most rigid members of splinted natural teeth or to the implants when they are united with natural teeth in a combined prosthesis. Implants always support the natural teeth and never the other way around. Therefore a nonrigid attachment is recommended between a tooth-supported prosthesis and an implant-supported prosthesis when they are combined. However, when implants are interspersed with natural teeth in the same prosthesis, the restoration will be implant borne. This requires special force distribution analysis to prevent implant overload.     

"Flocculus neonatorum": a self-resolving benign nodular flocculus of the iris in the newborn

A severely resorbed maxilla was reconstructed utilizing a combined surgical technique that included the placement of a horseshoe-shaped bicortical calvarium onlay graft, fixed by six endosseous implants. Two more implants were placed in the pterygoid process to support and stabilize the prosthesis. The dentition was rehabilitated with a fixed implant-supported hybrid prosthesis.     

Clinical case report: an improved technique for using dental implants as orthodontic anchorage

The use of endosseous implants as intra-oral anchorage to facilitate orthodontic treatment has been reported in the literature for some years, first in rabbits and dogs, and then in adult human patients. The implants were generally used solely for the purpose of anchorage. This paper reports the successful application of orthodontic forces utilizing dental implants to achieve tooth movement. The implants were subsequently used as fixtures in a pre-determined plan to support a fixed prosthesis. A clinical example demonstrates how implants may serve dual roles, for anchorage and then for fixed prosthetic support. The principles involved in using dental implants as part of a multi-disciplinary approach to dental treatment are illustrated.     

Primary insertion of osseointegrated dental implants into fibula osteoseptocutaneous free flap for mandible reconstruction

Twelve patients with segmental mandibular defects were reconstructed with fibula osteoseptocutaneous flaps and simultaneous placement of osseointegrated implants. Decision to perform this procedure was based on the facts that all patients had benign diseases, did not require postoperative radiotherapy, were in good general and oral conditions, and were psychologically motivated. A total of 34 fixtures was inserted in the first stage. Eight patients underwent second stage surgery, which consisted of connection of the implant abutments to the fixtures and the use of palatal mucosal grafts around the implants. Final dental prostheses were fixed 1 month later in seven patients, at this time. All flaps survived after surgery, and no implant failure was observed after a mean follow-up period of 25 months. Only one fixture was not used during the subsequent stage and was left as a sleeper. Fixed dental prostheses were used in five patients and removable overlay prostheses in the other two. Chewing function was recovered between 4 and 6 weeks after the start using the definitive dental prosthesis. In contrast to previous results, we conclude that excellent results can be achieved when this combined procedure is used in carefully selected patients. In addition, it is confirmed that the fibula osteoseptocutaneous flap is a versatile, reliable composite tissue that facilitates primary placement of osseointegrated dental implants during mandible reconstruction, thus allowing full oral rehabilitation in a shorter period of time.     

Covering extensive soft tissue defects in infected knee endoprostheses by gastrocnemius flap

Total knee arthroplasty has become a routine procedure in surgery. Deep infections have an incidence of 2-5%. Major risk factors are large prostheses, rheumatoid arthritis, diabetes mellitus and postoperative wound-healing complications. In large soft-tissue defects with skin necrosis, local wound care shows poor results, especially if loosening of the prosthesis and necrosis of the patellar ligament are evident. In these cases, no standard surgical therapy has been developed yet. Thus, we consider meticulous débridement with synovialectomy to be mandatory. Exchange of the prosthesis may be necessary. Soft-tissue coverage ought to be performed with a gastrocnemius muscle flap covered with a split-thickness skin graft. In the last three years, 11 patients with large soft-tissue defects and necrosis of the ligament were treated according to this concept. In all cases the muscle flap healed primarily and soft tissue coverage was excellent. Two patients who underwent single-stage removal and reimplantation of the prosthesis showed reinfections of the prosthesis. Reconstruction of the ligament was performed with the flap tendon. The patients with two-stage removal and reimplantation of the prosthesis and those who retained their implants had a good functional outcome. The gastrocnemius muscle flap provides easy and reliable soft-tissue reconstruction in large defects. In our patients a two-stage operation for reimplantation of the prosthesis was superior to a single-stage procedure. The reconstructed ligament should be reinforced with autologous material to prevent a secondary rupture. Early reconstruction with sufficient soft-tissue coverage and reconstruction of the ligament offers the patient the best chances of obtaining a good functional result and prevents arthrodesis or amputation. In addition, reconstructive surgery reduces the length of hospital stay and costs.     

Are mu-opioid receptors involved in the control of endothelin-1 release from the pituitary gland in normal and dehydrated rats?

A stereognostic ability test was performed in 60 patients. Forty patients were rehabilitated by means of osseointegrated implants. One group consisted of 20 patients with fixed prostheses on implants in both the upper and lower jaws. The other 20 patients had a maxillary denture while in the mandible an overdenture was retained by means of two implants connected by a bar. They were compared to a group of 20 subjects (controls) with a non-restored natural dentition. For the stereognostic ability test, subjects had to recognise ten different test pieces by manipulating them with two antagonistic incisor teeth, avoiding any contact with other oral structures. Both response time and percentage accuracy of recognition were evaluated. The present findings indicated that subjects with an overdenture on implants did not score significantly different from those with an implant-supported fixed prosthesis. In contrast, subjects with teeth had a significantly better stereognostic ability. The percentage of correct responses was 52% for overdentures, 56% for fixed prostheses on implants and 75% for natural dentitions. From these results, it could be concluded that the stereognostic ability is impaired in subjects rehabilitated with osseointegrated implants by about one-third to one-quarter compared to subjects with natural teeth.     

Immediate weightbearing after uncemented total hip arthroplasty

Radiographic subsidence of the femoral prosthesis and clinical results after unilateral and simultaneous bilateral uncemented total hip arthroplasty were compared. Patients who had bilateral total hip arthroplasty began weight-bearing as tolerated on both lower extremities the day after surgery. Patients who had undergone unilateral total hip arthroplasty were maintained at 10% weightbearing on the operative limb for 6 weeks after surgery. Patients in both groups were matched for age, gender, and weight. Minimal followup was 2 years. There was no difference between the two groups in terms of clinical results. Radiographic assessments were performed immediately after surgery, 6 weeks after surgery, and again at 2 years after surgery. Radiographs were reviewed by a single observer and analyzed with a digitized data recorder. Increased subsidence of the femoral prosthesis within the bilateral group was found at 6 weeks. The mean subsidence of the femoral prosthesis at 6 weeks for the bilateral total hip arthroplasty group was 0.86 mm (range, 0.18-2.60 mm) and for the unilateral group was 0.39 mm (range, 0.07-1.46 mm). However, subsidence occurring between 6 weeks and 2 years averaged 0.50 mm (range, 0.09-1.10 mm) for the bilateral group and 0.54 mm (range, 0.03-0.99 mm) for the unilateral group. This difference was not significant. At the 2-year followup, all femoral prostheses in both groups appeared radiographically stable with evidence of bone ingrowth and no indications of loosening. Thus, immediate weightbearing after bilateral total hip arthroplasty in this study resulted in more initial subsidence (during the first 6 weeks after surgery) of the femoral prosthesis but did not preclude the prosthesis from becoming stable and achieving bone ingrowth. Patients in both groups obtained satisfactory clinical results. Because initial stability and bone ingrowth are factors influenced by prosthesis design, the results of this study may not be applicable to all implants.     

Implant reconstruction of the jaws and craniofacial skeleton

Full oral rehabilitation with a high degree of success is now possible with osseointegrated implants. Osseointegration is a direct connection between living bone and the titanium implant at the level of the light microscope. Osseointegrated implants are currently used to replace single teeth, support fixed bridges and stabilize full dentures. These implants can also be placed extraorally for attachment of facial prosthesis. The surgical technique used to place implants intraorally into jaws or facial skeleton is performed in two stages using a local anesthetic and/or conscious sedation. During stage I surgery, holes are placed into the jaw using a series of gradually larger diameter burs until the desired diameter and depth of the bony preparation is achieved. The implant is then placed. The implant must remain undisturbed for 4 months for osseointegration to take place. Stage II surgery is then required to remove the mucosa over the implant and place the transmucosal abutment. After 1-2 weeks of healing, the restorative dentist can take an impression and fabricate the prosthesis. On occasion, it is necessary to augment the height and width of the atrophic jaw with autogenous or allogeneic bone grafts prior to implant placement. Bone grafts are sometimes placed on the floor of the nose or the floor of the maxillary sinus. Guided tissue regeneration is a technique used to generate bone within bony defects adjacent to implants. With long-term rates of success (5 years) of 99% for implants placed in the mandible and 95% for those placed in the maxilla, reconstruction of the jaws and cranial facial skeleton with osseointegrated implants has become the treatment of choice.     

Increase in skeletal muscle protein content by the beta-2 selective adrenergic agonist clenbuterol exacerbates hypoalbuminemia in rats fed a low-protein diet

Between 1990 and 1995, 214 implants were placed in 29 maxillae and mandibles of 22 patients following extraction of all residual teeth as a consequence of severe periodontal disease. All patients were discharged wearing immediate dentures. The implants were analyzed with regard to the number per arch, location, length, and diameter. The 5-year cumulative survival rate was 98.5%. The mean number of implants per arch was 7.5 for the maxilla and 7.2 for the mandible. The preferred implant locations were canines, central incisors, lateral incisors, and second premolars in the maxilla; and lateral incisors, first molars, and canines in the mandible. The mean implant length was 14.7 mm in the mandible and 14.5 mm in the maxilla. The mean implant diameter was 3.8 mm in the maxilla and 3.8 mm in the mandible. The results of the present study indicate that immediate implantation for fixed full-arch reconstruction can be considered a viable treatment alternative in patients with severe periodontal disease.     

Transthoracic and transesophageal echocardiographic study in aortic valve replacement with pulmonary valve autograft

Eleven patients who underwent pulmonary valve autograft to aortic position with placement of bovine pericardial prosthesis in pulmonary position were studied with echocardiography. Transthoracic echocardiography, was performed on all patients before surgery. Transesophageal echocardiograms were practiced during the surgical procedure. The latter technique aided in immediate postoperative evaluation. Transthoracic and transesophageal echocardiography provide a practical and valuable means of investigating the pre, trans and postoperative conditions of patients undergoing Ross surgery.     

Tooth stabilization and splinting before and after periodontal therapy with fixed partial dentures

The design and use of fixed partial dentures as a definitive restoration to stabilize and splint teeth have been reviewed. The provisionalization of the splinted patient has been described as it is incorporated into the treatment plan of patients with a weakened periodontium. The current controversy of incorporating implants in the patient requiring splinting was discussed, and recommendations are made. Dentists are encouraged to explain all potential ramifications of splinting with fixed partial dentures, including cost, frequency of office visits, and potential alterations or remakes of the prosthesis should physiologic demands surpass the capabilities of the remaining teeth.     

The diagnostic value of discography

BACKGROUND: Conjunctival cyst formation following enucleation may occur in 3% to 7% of patients receiving orbital implants, especially secondary implants. We present a patient with a giant epithelial inclusion cyst of the anophthalmic orbit 50 years after enucleation without orbital implant. PATIENT: A 54-year-old male presented with increasing proptosis of the ocular prosthesis, shallowing of the inferior fornix, a palpable orbital mass, and difficulty in retaining the ocular prosthesis. At the age of 1 year enucleation of the right eye without orbital implant was performed following perforating ocular trauma. Results of examination of the other eye were unremarkable. Transillumination of the orbital mass was possible. The clinical diagnosis of an epithelial inclusion cyst was confirmed using ultrasonography and CT scan. An incision of conjunctiva and cyst wall and subsequent marsupialization were performed. Nine months postoperatively there was no evidence of recurrence of the cyst. The ocular prosthesis was well in place. CONCLUSION: Conjunctival cyst formation following enucleation may rarely occur in patients receiving orbital implants, especially secondary implants. The presentation of a conjunctival cyst formation following enucleation without orbital implant 50 years after surgery is noteworthy in comparison to implantation cysts which are known to occur more commonly within the first two years following secondary orbital implants.     

Fabrication of a fixed partial denture in the Class II partial edentulous mandible using the UCLA abutment: a clinical report

Several methods are currently available to restore the partially edentulous patient with osseointegrated implants. The UCLA abutment eliminates the unesthetic, traditional transmucosal abutment and can provide esthetic crowns, fixed prostheses, and subgingival porcelain margins without the need for excessive instrumentation and components. A clinical report for the fabrication of a direct, implant-borne fixed prosthesis using the UCLA abutment is presented.     

Aesthetic considerations for maxillary obturators retained by implants

Maxillary obturators are prostheses used to replace maxillary tissues, missing congenitally or removed by trauma or tumor ablative surgery. These prostheses are used to restore function (speech, swallowing, and mastication) and aesthetics. A considerable number of edentulous patients have difficulty in retaining this type of prosthesis. Utilization of osseointegrated dental implants is a significant adjunct in treating these cases, but it must be undertaken with careful planning to ensure predictable aesthetic results. The learning objective of this article is to discuss the technique of designing aesthetic maxillary prostheses supported by osseointegrated dental implants. The discussion includes indications and contraindications, and a postcarcinoma surgery case is used to illustrate the clinical procedure.