An economic evaluation of maxillary implant overdentures based on six vs. four implants.

BACKGROUND: The purpose of the present study was to assess the value for money achieved by bar-retained implant overdentures based on six implants compared with four implants as treatment alternatives for the edentulous maxilla. METHODS: A Markov decision tree model was constructed and populated with parameter estimates for implant and denture failure as well as patient-centred health outcomes as available from recent literature. The decision scenario was modelled within a ten year time horizon and relied on cost reimbursement regulations of the German health care system. The cost-effectiveness threshold was identified above which the six-implant solution is preferable over the four-implant solution. Uncertainties regarding input parameters were incorporated via one-way and probabilistic sensitivity analysis based on Monte-Carlo simulation. RESULTS: Within a base case scenario of average treatment complexity, the cost-effectiveness threshold was identified to be 17,564 € per year of denture satisfaction gained above of which the alternative with six implants is preferable over treatment including four implants. Sensitivity analysis yielded that, depending on the specification of model input parameters such as patients' denture satisfaction, the respective cost-effectiveness threshold varies substantially. CONCLUSIONS: The results of the present study suggest that bar-retained maxillary overdentures based on six implants provide better patient satisfaction than bar-retained overdentures based on four implants but are considerably more expensive. Final judgements about value for money require more comprehensive clinical evidence including patient-centred health outcomes.

Intraoral framework pick-up technique to improve fit of a metal-resin implant prosthesis.

The achievement of passive fit is an important prerequisite for the prevention of complications in full-arch screw-retained implant prosthesis. With cemented prosthesis, the cementation compensates for the discrepancies in the cast framework, but the lack of retrievability seems undesirable. The aim of this paper is to propose a modified screw-retained prosthesis design for complete arch implant fixed rehabilitation. A technique for the fabrication of a full-arch metal-resin implant-supported screw-retained prosthesis is described. Cementation of the framework to the abutments intraorally improves the passivity of fit of the prosthesis on the implants. Maintenance of screw-access channels in the final prosthesis ensures retrievability. The metal-resin design allows for easy repair and maintenance. The prosthesis is cost-effective compared to conventional options and can be employed as a viable treatment alternative when considering metal-acrylic resin complete arch fixed prosthesis.

Patient satisfaction and oral health-related quality of life outcomes of implant overdentures and fixed complete dentures.

PURPOSE: To assess and compare patient satisfaction and oral health-related quality of life (OHQOL) in patients treated with implant-supported overdentures and complete implant fixed prostheses. MATERIALS AND METHODS: From a database of patients who had undergone implant treatment over a 6-year period, a study population of 62 patients was identified; every patient had at least four implants placed in one edentulous arch and was restored with either an overdenture or a fixed prosthesis. Patients were examined and a self-administered, structured multiple-response questionnaire, including the Oral Health Impact Profile-14 measurement tool and a patient satisfaction survey, was used to evaluate patient-centered treatment outcomes. RESULTS: Generally, patient satisfaction was very high in both the implant overdenture and fixed prosthesis groups, although the subjects in the overdenture group, who had mostly maxillary prostheses, reported significantly lower overall satisfaction and lower satisfaction with chewing capacity and esthetics. In just three categories--cost, satisfaction with treating doctor, and ability to perform oral hygiene measures--the fixed prosthesis group was less satisfied than the removable overdenture group, but the difference was not significant. Similarly, the overall OHQOL was high, although patients receiving a fixed prosthesis demonstrated significantly lower psychologic discomfort and psychological disability compared to the overdenture group. CONCLUSIONS: Among all patients who had similar numbers of implants placed, those who received an implant overdenture were less satisfied and had lower OHQOL than the patients who had a fixed prosthesis. Since patient and dentist preferences influenced the type of prosthesis provided, it is likely that subjective, patient-related factors are major determinants of satisfaction and treatment outcomes.

Private practice of prosthodontists: current conditions of practice in the United States.

PURPOSE: The purpose of this article is to examine data and results from the 2008 Survey of Prosthodontists. Survey results are used to examine current trends and characteristics of prosthodontists in private practice. MATERIALS AND METHODS: Characteristics of prosthodontists and conditions of private practice are based on surveys conducted in 2002, 2005, and 2008 sponsored by the American College of Prosthodontists. Survey results are used to estimate several characteristics including age, gender, number of patient visits, hours in the practice, employment of staff, referral sources, and financial conditions (gross receipts, expenses of the practice, and net income of prosthodontists). RESULTS: The average age of a private-practicing prosthodontist reached 51 years in 2007; 12.3 is the number of years in the current practice; and most prosthodontists (71%) are solo private practitioners. The average amount of time per week by prosthodontists in the practice averaged 36.1 hours, and prosthodontists treated an average of 44.1 patient visits per week. The largest source of patient referrals is the patient themselves. The largest percentage of a prosthodontist's treatment time is spent rendering procedures in fixed prosthodontics, but this percentage has declined since 2001. In 2007, the average gross billings of a practicing prosthodontist reached $805,675; average total practice expenses were $518,255; the mean net earnings of practitioners were $268,930. CONCLUSION: In 2007, prosthodontists in private practice paid out about $1.4 billion in practice expenses to provide $2.2 billion dollars in prosthodontic care. Based on survey results from 2007 and the previous 6 years, specialization in prosthodontic care continues to be an economically attractive and productive healthcare profession in the United States.

Prosthetic complications in an implant-retained mandibular overdenture population: initial analysis of a prospective study.

STATEMENT OF PROBLEM: The clinical success of implant-retained, tissue-supported mandibular overdenture prostheses has been documented. However, few studies have evaluated the return visits and associated cost required to maintain these prostheses. PURPOSE: The purpose of this investigation was to evaluate the amount of maintenance required to provide acceptable and satisfactory implant-retained mandibular overdentures in a prospective clinical trial. MATERIAL AND METHODS: Fifty-eight patients received new maxillary and mandibular complete dentures followed by placement of microthreaded/TiOBlast implants in the mandibular left and right canine regions. At 3 months, ball abutments were placed, and the mandibular prostheses were relined to receive Dalla Bona-type ball housings (baseline). Prostheses were prospectively evaluated, and adjustments were made at 3-, 6-, 12-, 24-, and 36-month recall visits and at nonscheduled visits for 9 types of prosthetic complications. RESULTS: Of 58 patients, 6 required no adjustments. The remaining 52 patients made 327 return visits (including 194 nonscheduled visits) for prosthesis and/or abutment adjustments. One hundred and fifteen practitioner hours were required to provide prosthetic solutions to patient concerns at the return visits. The total estimated cost for all professional and laboratory services was $12,624.00 ($218.00 per patient). CONCLUSION: Although mandibular implant-supported overdentures with Dalla Bona-type ball attachments are an acceptable treatment option for edentulous patients, routine maintenance is required to ensure successful long-term outcomes.

Treatment outcomes of fixed or removable implant-supported prostheses in the edentulous maxilla. Part II: clinical findings.

STATEMENT OF PROBLEM: There is a widespread belief that maxillary overdenture prostheses are associated with a higher frequency of complications and require more maintenance than fixed implant prostheses. PURPOSE: This prospective clinical study compared the treatment outcomes of fixed and removable implant-supported restorations in the edentulous maxilla with the main emphasis on the clinician's point of view. MATERIAL AND METHODS: Ten patients were treated with fixed screw-retained implant prostheses (group 1), and 10 patients were treated with removable implant-supported overdentures (group 2) in the edentulous maxilla. Recall was scheduled at 6-month intervals to investigate the prosthodontic treatment outcomes, including implant survival, prosthesis time until retreatment, and maintenance issues. Clinical parameters gingival index (GI), plaque index (PI), the clinical attachment level, and radiographic marginal bone levels measured, along with any biologic and mechanical complications were recorded. RESULTS: Patients were followed over a mean period of 39 months (SD=7; group 1) and 27 months (SD=10; group 2) after implant placement. Cumulative implant survival was 97.6% for group 1 and 94.4% for group 2 after an 18-month observation period. The mean time until retreatment after prostheses insertion was 23.4 months for group 1 and 19.8 months for group 2 (n.s.). In both groups, the increase over time in the radiographically investigated bone level was found to be significant. The indices given for the mucosal health and oral hygiene status (GI and PI) were highly correlated in both groups at each recall appointment, but no significant differences were found between groups 1 and 2. CONCLUSION: In groups 1 and 2, comparable prosthodontic treatment outcomes were achieved. The majority of mechanical complications could be managed chairside during recall visits and did not require additional appointments, so that the time and costs involved in providing maintenance were kept down.

Treatment outcomes of fixed or removable implant-supported prostheses in the edentulous maxilla. Part I: patients' assessments.

STATEMENT OF PROBLEM: Distinct clinical parameters determine whether fixed or removable implant-supported prostheses are indicated to restore the edentulous maxilla. However, there is a strong belief that fixed implant prostheses meet with greater patient acceptance and satisfaction, but this may differ from the patients' perceptions, their psychological responses to treatment, and their assessments of the treatment outcome. PURPOSE: This prospective clinical study compared the treatment outcomes of fixed and removable implant-supported restorations in the edentulous maxilla with the main emphasis on the patient's point of view. MATERIAL AND METHODS: Twenty patients who requested an implant-supported superstructure to restore the edentulous maxilla were asked to complete a questionnaire measuring their satisfaction with the present situation and the psychologic impact of their oral health status with their responses marked on a Visual Analog Scale (VAS). Ten patients were treated with a fixed, screw-retained implant prosthesis (group 1), and 10 were treated with a removable, implant-supported and bar-retained overdenture (group 2). Six months after prosthetic rehabilitation, patients were again given the questionnaire to assess their psychologic well-being and satisfaction with the implant-supported restoration. RESULTS: Both prosthesis designs were associated with significant improvements in comfort and retention, function, esthetics and appearance, taste, speech, and self-esteem. No difference was found between the 2 groups with respect to how the patients assessed the implant therapy. However, the results indicated that patients in group 2 experienced greater differences between pretreatment and posttreatment scores for the parameters esthetics, taste, and speech. Treatment costs per unit were significantly higher in group 1 than in group 2. CONCLUSION: Patients in groups 1 and 2 were similarly satisfied with their implant-supported prostheses in the edentulous maxilla with regard to their well-being and the cost-utility, irrespective of whether the restoration was fixed or removable.