Outcome assessment of implant-supported prostheses

STATEMENT OF PROBLEM: From the dental professional's standpoint, implant rehabilitation offers dramatically improved treatment alternatives to orally disabled patients. However, what a patient perceives as important to their function and satisfaction with their prostheses may be quite different from what the dentist believes are significant health-related improvements. PURPOSE: To resolve this problem, a series of investigations were designed to measure satisfaction and performance in groups of patients who wore various types of prostheses supported by endosseous titanium implants. MATERIAL AND METHODS: Methods are described for assessing treatment efficacy and population needs, including measures of perceived levels of disability, health-related quality of life, and functional capacity. RESULTS: The findings highlight patient factors that have not been considered before and appear to contribute to the success of prosthetic rehabilitation for the edentulous patient. CONCLUSION: Patient-centered approaches to the assessment of treatment efficacy are highly relevant to today's prosthodontists, whose goals are the improvement of function and quality of life for their patients.     

Clinical assessment of olfactory dysfunction in Parkinson''s disease

The possibility of placing endosseous implants in the edentulous maxilla is frequently reduced by inadequate bone volume of the residual ridge. In totally edentulous maxillae with knife-edge conformation, insufficient thickness is frequently associated with insufficient height of the residual ridge in the posterior maxilla because of pneumatization of the maxillary sinuses. This surgical method combines grafting of the maxillary sinuses, onlay grafts on the buccal side of maxillary posterior segments, and sagittal osteotomy of the anterior maxilla with interpositional bone grafts. Five to six months after maxillary reconstruction, Br?nemark implants were placed and, after osseointegration occurred, implant-supported dental prostheses were fabricated. Three patients have been treated with this method and 22 implants have been placed. The mean follow-up after final prosthetic rehabilitation has been 16 months; survival rate has been 100%. Despite the small number of patients and the short follow-up, preliminary results have shown very promising results.     

The use of osteotomes for sinus augmentation at the time of implant placement

The placement of endosseous dental implants is often hampered by the loss of alveolar bone. In the posterior maxilla, the presence of the maxillary sinus and less-dense bone present additional obstacles to successful implant placement. Existing methods of subantral augmentation require extensive surgical manipulation, often including a second surgical site for harvesting autogenous bone. The development of surgical osteotomes has facilitated the placement of implants in areas of minimal alveolar bone height in the posterior maxilla. This article describes the osteotome technique for sinus augmentation at the time of implant placement and presents a short-term evaluation of 34 implants placed in 18 patients.     

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.     

Endosseous implant and autogenous bone graft reconstruction of mandibular discontinuity: a 12-year longitudinal study of 31 patients

Surgical, medical, and prosthodontic records of 61 consecutively treated patients with mandibular discontinuity were reviewed retrospectively. All 61 patients had undergone discontinuity reconstruction with autogenous bone grafts; 31 of 61 had also received endosseous dental implants and a dental osseoprosthesis. Of these 31 implant-reconstructed patients, 23 had free autogenous nonvascularized and 8 had vascularized bone grafts. The surgical-prosthetic protocol consisted primarily of secondary, free autogenous nonvascularized bone graft reconstruction and secondary root-form endosseous implant and fixed prosthesis dental reconstruction. Vascularized bone (8 patients) or soft tissue (4 patients) grafts were utilized selectively for severely compromised patients after extensive oncologic resection, avulsive trauma, or after previous radiation treatment. Endosseous implant survival (95.5% in 31 patients), autogenous bone graft success (98.4% in 61 patients), and dental osseoprosthesis success (100% in 31 patients) were favorable. A high incidence (9.1%) of nonfunctioning (sleeping) implants was recorded for this patient population. The need to remove the titanium mesh tray for various reasons (17.6%) and the need to reconstruct soft tissue in the irradiated patient (12%) were noteworthy.     

Anterior aesthetic considerations for the placement and restoration of nonsubmerged endosseous implants

Nonsubmerged endosseous dental implants should be considered when planning optimal anterior implant rehabilitation. Detailed diagnostic records are a necessity, along with preoperative and preprosthetic treatment plans that are designed to address the unique challenges of anterior restorations. This paper discusses these concerns and presents two case reports which utilize some of the techniques that can be incorporated into achieving predictable anterior aesthetic rehabilitation using a single-stage implant. The learning objective of this article is to familiarize the reader with those challenges and techniques.     

Comparison of position repeatability of a human operator and an industrial manipulating robot

STATEMENT OF PROBLEM: Implant-supported restorations in the partially edentulous jaw have been performed at the Mayo Clinic for more than 10 years. Clinical performance of the implants and the prostheses should be reported to ensure effectiveness of this procedure. PURPOSE: This retrospective study described results for implant survival, implant fracture rate, prosthetic complications, and design changes that may impact these results. MATERIAL AND METHODS: A retrospective chart review was conducted of all registered implant patients in a large multispecialty medical center. Patients with a partially edentulous jaw who had received endosseous implants to support and retain dental prostheses were included in this review. Implant survival and fracture, prosthetic complications, and demographic data were recorded and analyzed through Kaplan-Meier methods. RESULTS: A total of 1170 implants were placed in four anatomic locations: anterior maxilla, posterior maxilla, anterior mandible, or posterior mandible. Location of implants was shown to have no effect on implant survival (p = 0.7398), implant fracture rates (p = 0.2385), screw loosening (p = 0.8253), or screw fracture (p = 0.2737). Development of new restorative components has resulted in significantly better rates of implant survival without fracture (p = 0.0054), screw function without loosening (p < 0.0001) and screw function without fracture (p = 0.0013). Implant survival seems to have been improved with the new components (p = 0.0513). CONCLUSIONS: Implant survival in this study was independent of anatomic location of implants. Virtually all clinical performance factors were improved by design changes in implant restorative components that were brought to market in early 1991.     

Dental implant outcomes in postmenopausal women undergoing hormone replacement

To determine if hormone supplementation reduces the risk of failure for osseointegration of dental implants in postmenopausal women, the treatment outcomes of 116 women older than age 50, treated with 450 endosseous dental implants, were analyzed in this retrospective study. The findings indicated that hormone replacement therapy may not be linked with improved outcomes of endosseous dental implant treatment in postmenopausal women. Smoking, however, appears to significantly increase the implant failure rate in the group observed in this study.     

Reconstruction of residual alveolar cleft defects with one-stage mandibular bone grafts and osseointegrated implants

PURPOSE: This study evaluates a treatment regimen for reconstruction of residual maxillary alveolar cleft defects consisting of mandibular bone grafting and immediate implant installation. PATIENTS AND METHODS: Sixteen cleft patients (five female and 11 male) had residual cleft defects of the alveolar ridge reconstructed with bone grafts from the mandibular symphyseal region. The bone graft was pretapped at the donor site before fixation in the residual ridge with Br?nemark implants. Twenty implants were installed according to this concept. The period of observation ranged from 36 to 69 months, with a mean of 48 months after implant installation. RESULTS: Five patients developed wound dehiscenses that resulted in total or partial bone graft sequestration. Two implants were lost, one due to sequestration and the other due to mobility at the abutment procedure; 18 implants were still well functioning at the end of the observation period. However, all patients showed significant periimplant bone resorption after this one-stage treatment. CONCLUSION: Because of the observed complication rate, the one-stage procedure may not be optimal for reconstructing residual cleft defects.     

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.     

Influences of smoking on the periodontium and dental implants

The purpose of this article is to review current information on the role of smoking in destructive periodontal disease and in increasing the likelihood of failure of endosseous dental implants. Practical recommendations are made on the role of the dental health professional in everyday dealings with patients who smoke.     

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.     

Interpositional bone grafting technique to widen narrow maxillary ridge

A narrow edentulous alveolar ridge, less than 6 mm in the buccopalatal aspect, can prevent restoration by means of endosseous implants. A widening technique using alveolar ridge splitting and interpositional autogenous bone grafting is described. Accurate imaging of the alveolar bone shape and size was assessed with computerized tomography in a 1:1 scale. Following 6 months of healing, osseointegrated Br?nemark implants were placed in the grafted sites.     

Reconstruction of an atrophic edentulous maxilla with unilateral cleft lip and palate (UCLP) using sub-antral augmentation and osseointegrated implants: case report and 3-year follow-up

With the current sophisticated, multidisciplinary approach to the treatment of cleft palate, it is anticipated that most patients with this deformity will enjoy good dental health and function. However, due to the number of older adults who were not treated with primary bone grafting and orthodontic therapy, there remains a significant number of potential candidates who may benefit from dental implants and implant-supported prostheses. Although it was not necessary in this case, a pharyngeal extension may be added to the maxillary denture to further improve speech and deglutition. This case report presents a three-year follow-up of a complex reconstruction of a highly compromised, edentulous patient. Stable fixation of the maxillary prosthesis results in a complete return to function in an individual for whom traditional dental prosthetics had resulted in ten years of failure and frustration. Combining the disciplines of reconstructive surgery and implant prosthetics enables the clinician to achieve a predictable result (Figures 12 and 13). While this case represents an extreme example, there are millions of patients for whom implant dentistry can provide life-changing benefits.     

Menopause: a new era

The Endopore implant provides a novel method for reliable fixation of endosseous dental implants within the bone. Through the use of a porous-surfaced zone formed by sintering Ti alloy particles of the appropriate size and under appropriate processing conditions to a sold Ti alloy core of desired shape (tapered truncated cone), an implant is now available that can be placed using a relatively simple surgical procedure using either surgical burs or hand osteotomes. Of even greater value is the suitability of this implant design for treatment of cases that because of minimal bone height cannot be treated routinely using other currently-available implants. The high success rates experienced with significantly shorter implant lengths compared with other designs indicate the appropriateness of this system for difficult-to-treat cases. The Endopore system represents the next generation of endosseous dental implants characterized by uncomplicated and reliable treatment for a wider range of dentally-compromised patients. Its history is founded on extensive and fully-documented research at the human preclinical stage as well as human use experiences. The results during the past nine years have confirmed the high expectations that those early studies suggested.     

Effects of irradiation on osseointegration before and after implant placement: a report of three cases

Three patients irradiated as a part of cancer treatment, both before and after placement of endosseous implants, were studied. Total irradiation doses varied from 80 to 195 Gy in the tumor/implant area. Implants failed at a rate of 64.2% during a 3-year follow-up period. All patients developed osteoradionecrosis in the tumor cavities adjacent to the implants. The combined effects of the pre- and postoperative irradiation, in conjunction with the placement of implants, appear to challenge the limits of osseointegration. Until further knowledge is obtained regarding how such highly radiated tissue should be handled, it is recommended that if anchorage of craniofacial prostheses is attempted according to osseointegration principles, it should be performed with the utmost care.     

Predictors of underlying coronary artery disease in cocaine associated myocardial infarction: a meta-analysis of case reports

A preliminary report presenting the results of fibular strut grafting in the severely resorbed mandibular and maxillary region is presented. Thirteen patients were treated due to severe resorption of alveolar and basilar bone of 49 segments of the mandible and the maxilla. Two patients additionally had pathological fractures of the mandible. In 10 cases the strut graft was harvested by means of a new minimally invasive technique. After modelling the fibular bone it was fixed to the recipient site by miniscrews or implants. After a mean follow-up period of 20 months (max. 31, min. 11 months) a retrospective analysis of clinical and radiological findings was carried out. It showed that a mean augmentation of 16 mm was achieved. Compared to other studies the fibular strut graft was resorbed less, and due to the primary stability it could be used for the treatment of fractures of the mandible. No more than natural resorption was observed when the patients received their prostheses fixed to dental implants.     

Single tooth, implant-stabilized crowns replacing anterior teeth: a clinical comparison of two systems

Implant-supported single-tooth crowns are suitable alternative restorations to partial dentures and bridges. A number of systems have been developed to create a good aesthetic result without the display of the standard titanium abutment traditionally used in restorations with complete fixed prostheses supported by titanium endosseous implants. This paper reviews two such systems.     

Primary diffusely infiltrative adenocarcinoma of the colon and rectum

In this study, patient opinion on oral rehabilitation by means of Br?nemark implants was investigated. All patients were referred to a periodontal clinic for implant installation and treated by one and the same operator. Prosthetic restorations were performed by dentists, who had no previous experience with prostheses on implants, but had completed a postgraduate training course. Patient opinion was obtained through questionnaires, pertaining to satisfaction and oral function. A comparison was made between pre-implant situation, short-term (< 4 months) and long-term functioning (3 years) with the implant-restorative rehabilitation. In total, 61 patients participated in the study; 23 received a full lower arch bridge and 18 a full upper arch bridge, while 20 patients got partial bridges. Of 298 installed implants, 7 failed at abutment connection (2.3%) and 1 during the 3-year follow-up interval (0.3%). The study results indicated that a great majority of patients were very satisfied with the treatment. Comfort with eating, aesthetics, phonetics and overall satisfaction improved significantly and nearly all patients said that they would undergo the treatment again or recommend it to others. Patients experienced their implants as "natural" teeth. The conclusion is that rehabilitation ad modum Br?nemark, even in the hands of non-specialized dentists, can be of high quality, improving oral function and satisfying the needs and demands of patients.