Cost-effectiveness analysis of dental implants

In this article the cost-effectiveness of dental implants (rootform and transmandibular) is compared with making complete dentures combined with vestibuloplasty and just a set of new dentures. The cost components of labour and technique are analysed at the individual patient level. Effectiveness was measured using a ratio scale. Several assumptions for the long run effectiveness of the treatment options are necessary due to lack of information about this in the literature. Assumptions were made regarding: survival rate, life span of dental implants and complete dentures, costs of aftercare and development of oral health in the long run. The main conclusion is that overdentures on rootform implants are superior to complete dentures combined with preprosthetic surgery or overdentures on a transmandibular implant. The choice between treatment with rootform implants or just a new set of dentures is a more difficult matter.     

A clinical trial of patient satisfaction and prosthodontic needs with ball and bar attachments for implant-retained complete overdentures: three-year results

STATEMENT OF PROBLEM: Few prospective trials of implant-retained mandibular dentures have evaluated the increase and duration of patient satisfaction, costs of denture maintenance in relation to different methods of attaching overdentures to implants, or the use of a reinforced framework. PURPOSE: This report evaluates subjects' satisfaction and prosthodontic maintenance during a 3-year randomized clinical trial of implant-retained mandibular complete dentures, whether reinforced or not with a cast framework, and attached by bar-clip or 2.25-mm ball-spring matrices to endosteal dental implants. MATERIALS AND METHODS: One hundred edentulous subjects, each having at least 1 year's experience with conventional complete dentures, were selected from respondents to a university dental clinic's request for volunteers. Candidates were examined to verify adequate mandibular bone and medical suitability for implants. Subjects then received 2 implants in the anterior mandible before being stratified by mandibular bone height and gender and assigned randomly to 1 of 4 treatment groups. Every subject received a new maxillary complete denture in addition to an implant-supported mandibular complete denture, with or without a reinforcing framework, connected to implants by either a bar-clip or a ball-spring patrix and matrix. The dentures were adjusted and repaired as needed. Subjects indicated on a visual analogue scale (VAS) satisfaction with conventional dentures prior to the study and then with new dentures at 1 month, 1 year, and 2 years. The results reported here are from the first 68 subjects observed for 3 years after receiving new dentures (19 subjects received new dentures less than 3 years before this analysis, and another 13 subjects were lost to follow-up). VAS scores are presented in simple tables and graphs, and results for different groups were compared using 2-sided nonparametric rank tests and repeated measures ANOVA. With respect to costs and maintenance, t tests were used to compare group means. Sample size and other design considerations used a .05 significance level. RESULTS: After receiving new dentures with mandibular implant supports, improved satisfaction "within subject" was prompt, durable, substantial, and statistically significant, regardless of the attachment mechanism, and with or without a reinforcing framework. In contrast, there were no notable satisfaction differences between the 2 attachment mechanisms, or with the presence or absence of a reinforcing framework, either at specific intervals after receiving the new dentures, or in repeated measures ANOVA. For both attachment groups, most denture adjustments occurred during the first year. This accounted for 81% of total adjustments during 3 years, when the 34 subjects in the ball-spring group and the 34 in the bar-clip group were combined. The mean numbers of adjustments per subject and associated clinical times did not differ significantly between the 2 groups. Conversely, denture repairs declined more slowly than adjustments. Almost all repairs (90%) occurred in the ball-spring group to correct problems with the attachments, 39% in the first year, and tapering off only slightly in the following 2 years. Over 3 years of follow-up, mean numbers of repairs per subject differed significantly between groups: 6.7 repairs per person in the ball-spring group, compared to 0.8 in the bar-clip group ( P<.001), and mean time per appointment was greater for repairs in the ball-spring group: 18.9 minutes compared to 16.9 ( P<.01). The cast framework had no influence on the satisfaction expressed or on adjustments and repairs. CONCLUSION: Subjects were very satisfied with the new dentures, although the ball-spring attachment tested in this trial required substantially more repairs.     

Use of mini implants for replacement and immediate loading of 2 single-tooth restorations: a clinical case report

Numerous long-term studies have shown that treatment with dental implants can provide edentulous patients with a more stable alternative to complete dentures and partially edentulous patients with a more conservative form of tooth replacement than conventional fixed partial dentures. Until recently, commercially available dental implants have been limited to diameters ranging from 3.0 mm to 7.0 mm. Although this range of diameters has been able to address most clinical needs, partially edentulous patients who could not accommodate a 3.0-mm-diameter implant without damaging adjacent dental structures were excluded from implant therapy. This article reports on the surgical treatment and immediate restoration of a patient who received mini implants that were 2.4 mm in diameter.     

口腔种植修复临床效果五年回顾研究

目的:评估柱状种植体应用5年的临床效果。方法:2001年2月至2005年12月植入柱状种植体共931枚,其中Pitt-easy种植体174枚,Frialit-2种植体148枚,Camlog种植体350枚,XiVE种植体176枚,Ankylos种植体45枚,I.M.Z种植体38枚。全部种植体均在2005年12月前完成上部结构修复,其中固定修复456例,活动修复8例,共计464例患者。平均追踪30个月(4-59月)。观察方法为X线检查和临床检查,采用Wheeler存留标准评估,纳入Kaplan-Meier存留曲线统计。结果:种植修复体完成时451例患者对修复效果满意,13例患者对修复体不满意,重做后10例表示满意,3例表示可以接受。随访中有34例患者共46枚种植体确诊为种植体周围炎。有明确记录的共24枚种植体脱落。5年随访累计修复体松动14件,修复体折断8件。据Wheeler存留标准统计5年存留率为95.2%。结论:种植修复患者的满意度高,本组种植体的5年存留率达到95.2%。     

12例重度慢性牙周炎患者全颌种植义齿修复的临床观察

目的探讨对经牙周治疗的重度慢性牙周炎患者拔除剩余牙齿后同期植入种植体并采用全颌种植义齿修复的可行性。方法对12例重度慢性牙周炎患者行牙周治疗，控制病情后，拔除剩余牙齿并同期植入种植体，5～6个月后行全颌种植义齿修复。根据临床、X线检查和患者主诉评价修复效果。结果共计108枚种植体植入20个牙弓，其中37枚种植体即刻植入拔牙窝内。种植体平均承载3年，所有种植体均无松动。2枚种植体发生种植体周围炎，有进行性骨吸收，其中1枚为即刻植入拔牙窝内的种植体。除2枚有进行性骨吸收的种植体外，其余种植体周围的骨吸收高度平均为（1．33±0．10）mm。108枚种植体的存留率为98．1％，37枚即刻种植体的存留率为97．3％。结论对重度慢性牙周炎患者行牙周治疗后拔除剩余牙齿并同期植入种植体，采用全颌种植义齿修复，可减少牙槽骨的吸收、缩短种植修复疗程，在定期的口腔卫生维护下获得理想的修复效果。     

Dental implants: a survey of patients' attitudes

This study measured the psychologic attitudes of patients to implant prostheses and compared their status before and after therapy. Questionnaires were mailed to 95 patients with implants placed and restored at a university dental school. The implants had been in position for an average of 2.2 years. The patients had previously worn removable complete or partial dentures. Different questions addressed eating, speaking, relationships, employment, social life, esthetics, maintenance, and overall dental health. Sixty-one questionnaires were returned (64%). Satisfaction with the implant prosthesis was significantly greater than for the denture (p less than 0.0001). Responses to individual questions indicated that confidence was improved (88%), implants were worth the trouble (97%), the procedure would be worth repeating (89%), and overall dental health was improved (98%). This survey suggests that patients' attitudes toward their dental health improve significantly after treatment with implant prostheses.     

Implant‐Retained Removable Partial Dentures: An 8‐Year Retrospective Study

Purpose: To evaluate the long‐term outcomes of removable partial dentures (RPDs) retained (but not supported) by dental implants. Materials and Methods: We retrospectively evaluated 32 consecutive patients who received implant‐retained RPDs. Each patient received one to four endosseus implants; the sample included a total of 64 implants. Follow‐up was conducted for a minimum of 8 years, during which satisfaction, implant survival, and prosthetic success were evaluated. Results: Patient satisfaction systematically increased. The implant success rate was 93.75%, and 100% of the prostheses were successful. Conclusion: Implant‐retained RPDs are a reliable intermediate solution that can reduce biological and economic costs while maintaining implant treatment benefits and the ease of RPD procedures.     

Progress and trends in patients' mindset on dental implants. II: implant acceptance, patient-perceived costs and patient satisfaction

Objectives: Compared with widespread investigations on dental implant survival and biologic parameters, patient‐based outcomes of implant dentistry have been neglected for years and are now becoming more popular. The aim of this representative opinion poll was to assess the up‐to‐date patients' mindset on dental implants and draw comparisons with the results published in 2003. Material and methods: One thousand adults – representative for the Austrian population – were presented with a total of 16 questionnaire items regarding acceptance and subjectively perceived costs of dental implant treatment as well as patient satisfaction with implant‐supported rehabilitation. Results: The implant acceptance rate was 56%, while 23% of the interviewees decidedly rejected implant treatment (same rate as in 2003), especially those over 50 years of age. Only 5% had themselves undergone implant treatment and 22% reported to know someone fitted with implants. The estimated costs of implant treatment were significantly higher than those in 2003, and three‐quarters felt that the prize was too high and that the sick fund or social security agencies should bear them. Satisfaction scores were significantly higher among interviewees wearing implant‐supported rehabilitations compared with those with conventional fixed or removable dentures. Conclusions: Little has changed in patients' attitude toward dental implants compared with the representative opinion poll in 2003. Neither implant acceptance nor implant prevalence in the Austrian population demonstrated upward trends. Professional public relations efforts are indicated to drop resentments and increase patient acceptance of dental implants as a treatment modality. To cite this article :
Pommer B, Zechner W, Watzak G, Ulm C, Watzek G, Tepper G. Progress and trends in patients' mindset on dental implants. II: implant acceptance, patient‐perceived costs and patient satisfaction.
Clin. Oral Impl. Res. 22 , 2011; 106–112.
doi: 10.1111/j.1600‐0501.2010.01969.x     

Economic aspects of single-tooth replacement

The aim of this study was to assess and compare economic parameters of two treatment options in patients requiring single-tooth replacements in private practice. Thirty-seven patients received 41 conventional three-unit fixed partial dentures (FPDs). Fifty-two patients received 59 single crowns on implants (I). Treatment assignment was not random. All except one were metal ceramic reconstructions. All except one were crowns cemented on solid abutments of the ITI((R)) Dental Implant System. Economic parameters were noted for the preparatory phase, the actual reconstruction and for treatment of biological and/or technical complication thereafter (range 1-4 years): number of visits, chair-side time, treatment costs, costs for implant components and laboratory work. Costs were based on the tariffs between the Swiss dentists association and the insurers (Sfr 3.1 per tariff point). Implant treatment required more visits than FPD (8.1+/-2/4.8+/-2.3, chi(2): P=0.02). However, the total treatment time was similar (I: 4.8 h+/-0.9 h/FGM: 5.1 h+/-1.3 h, NS). Laboratory costs were higher for FPD (1527.8+/-209 SFr) vs. 579.6+/-106.9 CHF for I. Costs for treatment of technical and biological complications were similar. Total costs amounted to 3939.4+/-766.4 SFr for FGM vs. 3218+/-512.2 SFr for I (P<0.003, Kolmogorov-Smirnov). Even when considering opportunity costs (50 SFr) for each visit the implant solution was less expensive: 3623.2+/-656.1 SFr vs. 4178.7+/-822.1 SFr (P<0.04, Kolmogorov-Smirnov). Costs for treatment of complications were similar. In conclusion, over a short observation period, the implant reconstruction demonstrated a more favorable cost/effectiveness ratio. Especially in clinical situations with either non- or minimally restored teeth and sufficient bone, the implant reconstruction is to be recommended from an economical point of view.     

Changes in bite force and chewing efficiency after denture treatment in edentulous patients with denture adaptation difficulties

Masticatory function was studied by means of a chewing efficiency test and bite forces measurements in forty-nine edentulous patients who had applied for treatment with fixed protheses on osseointegrated dental implants. Registrations were performed with the original complete dentures and after treatment aiming at optimizing the dentures. The patients were divided into two groups and the post-treatment recordings were completed after adaptation periods of 2 and 6 months, respectively. The functional tests showed mainly small and non-significant changes after the denture treatment. Improvement was greater, however, in those with the poorest pre-treatment values. Chewing efficiency deteriorated after treatment in the older patients (more than 50 years) while it did not change in the younger ones. A longer adaptation period did not lead to better functional results. The findings are discussed in relation to the fact that the patients were waiting for implant treatment, with consequent psychological implications for interpretation.     

Long-term effects on chewing with mandibular fixed prostheses on osseointegrated implants

Twenty-seven edentulous patients with denture adaptation problems were first given optimal conventional complete dentures and then a fixed prosthesis on osseointegrated dental implants in the lower jaw (and a complete maxillary denture). Masticatory function was evaluated by means of a questionnaire, a comminution test for chewing efficiency, and bite force measurements on four occasions: with the original (I) and optimal complete dentures (II) and 2 months (III) and 3 years (IV) after insertion of the fixed mandibular prosthesis on implants. No significant improvement of masticatory function was found after conventional denture treatment. After insertion of the fixed mandibular implant bridge, a marked improvement of the patients' assessment of their chewing ability and of the results of the chewing efficiency test and the bite force measurements was recorded. The test results were further improved after the 3-year observation period, which indicates that adaptation to the new prosthetic situation is a gradual process.     

Cumulative costs for the prosthetic reconstructions and maintenance in young adult patients with birth defects affecting the formation of teeth

Objectives: To assess retrospectively the cumulative costs for the long-term oral rehabilitation of patients with birth defects affecting the development of teeth.
Methods: Patients with birth defects who had received fixed reconstructions on teeth and/or implants ≥5 years ago were asked to participate in a comprehensive clinical, radiographic and economic evaluation.
Results: From the 45 patients included, 18 were cases with a cleft lip and palate, five had amelogenesis/dentinogenesis imperfecta and 22 were cases with hypodontia/oligodontia. The initial costs for the first oral rehabilitation (before the age of 20) had been covered by the Swiss Insurance for Disability. The costs for the initial rehabilitation of the 45 cases amounted to 407,584 CHF (39% for laboratory fees). Linear regression analyses for the initial treatment costs per replaced tooth revealed the formula 731 CHF+(811 CHF × units) on teeth and 3369 CHF+(1183 CHF × units) for reconstructions on implants ( P <.001). Fifty-eight percent of the patients with tooth-supported reconstructions remained free from failures/complications (median observation 15.7 years). Forty-seven percent of the patients with implant-supported reconstructions remained free from failures/complications (median observation 8 years). The long-term cumulative treatment costs for implant cases, however, were not statistically significantly different compared with cases reconstructed with tooth-supported fixed reconstructions. Twenty-seven percent of the initial treatment costs were needed to cover supportive periodontal therapy as well as the treatment of technical/biological complications and failures.
Conclusion: Insurance companies should accept to cover implant-supported reconstructions because there is no need to prepare healthy teeth, fewer tooth units need to be replaced and the cumulative long-term costs seem to be similar compared with cases restored on teeth.     

An economic evaluation of implant treatment in edentulous patients-preliminary results

PURPOSE: Edentulous patients with denture problems benefit from implant treatment with overdenture prostheses. The aim of this prospective study was to investigate a method of analyzing cost effectiveness in dentistry. As an example, overdenture treatment with two or four implants was compared to the conventional complete denture (CD). MATERIALS AND METHODS: In a self-selected trial, 20 patients each were treated with implant-retained overdentures (two implants, IRET), implant-supported overdentures (four implants, ISUP), or CDs (control group) in the edentulous mandible. A cost-effectiveness analysis was performed from the patient's perspective, with a time horizon of 6 months. Direct health-care costs were calculated in Swiss Francs (in 2000), and effects were defined as improvements in perceived chewing ability compared with the baseline value before treatment (measured on a VAS). Point estimates for mean incremental cost-effectiveness ratios were complemented with cost-effectiveness acceptability curves to account for uncertainties associated with costs and effects. RESULTS: Mean incremental costs were CHF 4,329 (IRET-CD), CHF 13,360 (ISUP-CD), and CHF 9,031 (ISUP-IRET); these cost differences were all statistically significant. The mean incremental effects at 6 months were 19% (IRET-CD), 23% (ISUP-CD), and 4% (ISUP-IRET). Incremental cost-effectiveness ratios were CHF 228 (IRET-CD), CHF 581 (ISUP-CD), and CHF 2,258 (IRET-ISUP) per percentage increase in chewing ability. CONCLUSION: From an economic point of view, IRETs were more attractive than ISUPs. The latter were associated with a statistically significant improvement in perceived chewing ability compared to CDs, but at substantially higher costs.     

慢性中重度牙周炎患者应用种植修复的临床评价

目的：评估对中重度牙周炎患者经完善的牙周治疗及Ⅱ-Ⅲ度松动牙拔除后所导致的牙列缺损及牙列缺失所采用的单冠,联冠,全颌种植义齿修复的远期疗效。方法：共计十例患者经完善的牙周治疗,病情稳定后延期植入80枚种植体,即刻植入16枚植体,5-7个月种植义齿修复,根据种植体与牙槽骨之间的X线影像,牙周袋深度及临床检查等作为评价指标,评价负载后的修复效果。结果：96枚种植体中,其中两枚即刻种植于术后3周脱落,即刻种植成功率87%,种植体的平均存留率为97%,承载3.5年后骨吸收高度平均为（1.73＋0.13）mm。结论：对中重度牙周炎进行牙周治疗,采取慎重态度,运用正确的种植方式,修复方法,则可减少牙槽骨的吸收,并获得理想的修复效果,但同时要坚持定期的口腔护理,但对这类患者的骨吸收还需进一步的远期观察。     

杆-卡结构种植覆盖义齿修复

本文对5例无牙颌患者，6副种植体支持的杆-卡结构种植覆盖义齿作2年的追踪观察资料作了总结。种植体为覆盖义齿提供了满意的支持。固位和稳定作用，增进了咀嚼功能的发挥。未见种植体松动和牙槽骨严重吸收。正确拟订治疗计划，术后戴用过渡性修复体，杆卡符合一定力学要求，正确处理义齿关系等均促成种植体的高成功率（100％）。修复后的定期检查，维护修复体、种植体及杆的清洁，对确保修复的成功具有重要意义。杆卡结构种植覆盖义齿修复牙槽嵴严重吸收的无牙颌是可行的。     

Patient expectations of oral implant-retained prostheses in a UK dental hospital

STATEMENT OF PROBLEM: The loss of the natural dentition leads to severe functional impairment in many edentulous adults. A prosthesis retained and supported by osseointegrated dental implants may provide a satisfactory solution for people who have lost all their natural teeth. However, little information is available as to what patients requesting implants expect of implant-retained prostheses. AIM: The aim of this study was to assess the expectations of a group of edentulous patients requesting implant therapy. METHOD: The study included two groups: (1) a group of edentulous adults who requested implant therapy ('implant group'); and (2) an edentulous control group, of similar age and gender distribution as the implant group, receiving conventional complete dentures. Following a clinical and radiographic examination of the patients, data were collected using validated questionnaires. Both groups made a subjective assessment of current dentures. The implant group also completed a questionnaire which assessed expectations of implant-retained prostheses. RESULTS: Baseline satisfaction with current dentures was low in both groups, with the implant group being significantly less satisfied with comfort and stability of their mandibular dentures. Perceived ability of the implant group to chew hard foods was less than the control group. The implant group's expectations of an implant-retained prosthesis were significantly greater than for a conventional denture. CONCLUSION: Careful assessment of patient expectation of implant therapy is essential to determine appropriate treatment need, and to highlight unrealistic expectations.     

口腔种植修复临床效果十年回顾研究

目的评估骨结合种植体应用10年的临床效果。方法1994年8月至2004年8月在北京大学口腔医学院·口腔医院口腔种植中心植入的骨结合种植体共5590枚,其中Branemark种植体161枚,Frialit-2种植体1436枚,IMZ种植体1012枚,Ankylos种植体767枚,Camlog种植体2189枚,Komet种植体25枚。全部种植体均在2004年8月前完成上部结构修复,其中固定修复2314例,活动修复315例,共计2629例患者。平均追踪77·2个月(7~121个月)。观察方法为X线检查和临床检查,采用Wheeler存留标准评估,纳入Kaplan-Meier存留曲线统计。结果种植修复体完成时2624例患者对修复效果满意,5例患者对修复体不满意,重作后4例表示满意,1例表示可以接受。随访中有105例患者共178枚种植体确诊为种植体周围炎。有明确记录的共68枚种植体脱落。10年随访累计修复体松动21件,修复体折断4件,烤瓷冠崩瓷51件。据Wheeler存留标准统计10年存留率为96·7%。结论种植修复患者的满意度高,本组种植体的10年存留率达到96·7%。     

种植体与天然牙联合修复牙列缺损86例临床分析

目的:评价种植体与天然牙联合修复牙列缺损的效果.方法:86例患者缺牙隙均为牙槽骨中度以上吸收以及(或)下牙槽神经管位置相对偏高,或上颌窦过低(管嵴距、窦崤距<10mm).种植101颗国产两段式纯钛种植体,3～6个月后采用天然牙与种植体联合方法修复.结果:修复后观察2～3a,有效率达93.4%.结论:单纯采用种植体修复受到解剖结构限制时,采用种植体与天然牙联合修复不失为一种简便、有效的方法.     

Influence of implant and conventional prostheses on satisfaction and quality of life: A literature review. Part 2: Qualitative analysis and evaluation of the studies

PURPOSE: To review the influence of prosthodontic and dental implant treatment on patient satisfaction and oral health-related quality of life (OHQOL) based on a systematic search of the literature. MATERIALS AND METHODS: A systematic literature search was carried out for articles published between 1960 and February 2003. Details of the search process and results were reported in Part 1 of the study (Int J Prosthodont2004;17:83-93). The included studies were categorized and evaluated according to their level of evidence, following the guidelines of the Agency for Health Care Policy and Research. The characteristics and content of the studies were analyzed and tabulated. RESULTS: Among the 114 included studies, there were 76 publications reaching evidence level III. The results showed that the effects of compromised oral health are not limited to traditional clinical aspects, but can considerably affect patients in various activities of daily life. Twenty-four of the 38 investigations with evidence levels I and II dealt with implant stabilization of complete mandibular prostheses, comparing implant prostheses to conventional complete dentures. Fully edentulous patients experience negative impacts on OHQOL from their condition. They benefit significantly from the use of dental implants to support mandibular prostheses. However, support by more than 2 implants does not appear to further significantly increase patient satisfaction and OHQOL. CONCLUSIONS: To date, research in the field of patient-based outcomes has concentrated on dental implant treatment for the edentulous patient. Other prosthetic treatments such as single crowns, fixed and removable partial dentures, or further treatment concepts (eg, the shortened dental arch concept) are not well represented. The use of patient-centered outcome measures can help to find an individual, patient-oriented prosthetic solution.