Mini-Implants for Mandibular Overdentures: Cost-Effectiveness Analysis alongside a Randomized Trial

Abstract

Mandibular overdentures retained by 2 conventional implants have been considered the standard of care for complete edentulism, according to the McGill and York consensuses. However, many patients refuse this treatment modality due to the associated costs and postsurgical discomfort. Mini-implants have the chance to overcome these limitations due to their potentially lower costs and a relatively uncomplicated surgical technique. This study compared treatment costs and incremental costeffectiveness following the insertion of mini-implants (2 or 4) or 2 standardsize implants for the retention of mandibular overdentures, by means of a randomized clinical trial. In total, 120 edentulous participants (mean age 59.5 ± 8.5 y) were randomly allocated into 3 groups according to treatment received: 4 mini-implants (group 1), 2 mini-implants (group 2), or 2 standard implants (group 3). Treatment costs and outcomes (Oral Health Impact Profile for Edentulous [OHIP-EDENT] and satisfaction with the dentures) were evaluated after 6 mo. Incremental cost-effectiveness ratios (ICERs) were calculated for each intervention in terms of cost per 1-point change in patient outcomes. A 1-way sensitivity analysis was performed considering a 95% confidence interval variation in cost and outcome parameters, represented in tornado diagrams. Overall treatment cost was the lowest for group 2 (average cost: US$318.08), followed by group 1 (US$510.75) and group 3 (US$566.13). Groups did not differ in terms of the length of unscheduled appointments and time spent by participants. In summary, our findings indicate that mandibular overdentures retained by 2 or 4 mini-implants are less costly compared to 2-implant overdentures. Despite the lower costs of overdentures retained by 2 mini-implants, those retained by 4 mini-implants showed further improvement in patient-reported outcomes and reduced costs compared to standard implants (ClinicalTrials.gov NCT01411683). Knowledge Transfer Statement: This report shows that mini-implant retained overdentures are less costly than overdenture treatment on 2 standard-sized implants. Treatment with 2 mini-implants is an effective procedure to substantially save resources, whereas treatment with 4 mini-implants provides better results from a patient perspective combined with slightly reduced costs compared to the treatment with 2 standard implants. Therefore, mini-implant overdentures may be effective and more accessible than overdentures on 2 standard-size implants for those with limited incomes.

Patient‐based outcomes with conventional or mini‐implants immediately loaded with locator‐retained mandibular overdentures: A cohort study

“…15 For this purpose, we used two psychometric instrument tools OHIP-14 and DSQ as reported by previous studies. 3,21,22 Other authors have used other questionnaires such as the OHIP-EDENT, 14,[23][24][25] "Daily Impact on Daily Living," 25 and Visual Analogue Scales. 23,26 However, a review on the use of OHIP in clinical implant research identified OHIP-14 as the most popular instrument to use when measuring outcomes in edentulous patients.…”

“…3,21,22 Other authors have used other questionnaires such as the OHIP-EDENT, 14,[23][24][25] "Daily Impact on Daily Living," 25 and Visual Analogue Scales. 23,26 However, a review on the use of OHIP in clinical implant research identified OHIP-14 as the most popular instrument to use when measuring outcomes in edentulous patients. 27 To our knowledge, however, this is the first study comparing OHrQoL and satisfaction in overdenture patients treated with two conventional diameter implants or mini-implants using the same abutments (Locators).…”

What is the evidence on the added value of implant‐supported overdentures? A review

“…Most studies compared the IOD to the original CD 28,30–32,35–40 . In two studies, patients were divided into groups in which patients received a new CD or a IOD‐2 29,37 .…”

“…PROMs can be expressed using satisfaction questionnaires. For example, the McGill denture satisfaction questionnaire 46 was applied by Della Vecchia and colleagues 28 . Using a VAS scale (0–100 mm), the following variables were assessed: general satisfaction, ability to speak, and esthetics.…”

“…The effect of treatment using the OHIP system as PROM is depicted in Table 5. The OHIP‐20 questionnaire was applied in four studies, 29,30,33,34 the OHIP‐14 in two studies, 38,39 and the OHIP‐EDENT in one study 28 . Sometimes different Likert scales were used; for example, with total scores in the range of 0–80 29,33 or of 20–100 34 .…”