A pilot randomised controlled trial evaluating mini and conventional implant retained dentures on the function and quality of life of patients with an edentulous mandible

Abstract

BackgroundTotal tooth loss (edentulism) can be a debilitating condition, impacting on ability to chew, speak and interact with others. The most common treatment is with complete removable dentures, which may be successful, but in the lower jaw, bone resorption that worsens over time makes denture-wearing difficult. Two dental implants in the mandible to retain the lower denture has been advocated as the gold standard of treatment, but has not been universally provided due largely to financial constraints and also patient fear. Mini implants (MI) are cheaper and less invasive than conventional implants (CI), but may not have equivalent longevity. Therefore, it is unknown whether they represent a cost-effective treatment modality over time. The aim of this pilot randomised controlled trial was to assess the feasibility of carrying out a trial on this cohort of patients, and to inform the study design of a large multicentre trial.MethodsForty-six patients were randomly allocated to receive either two mini implants or two conventional implants in the mandible to retain their lower dentures. Quality of life (QoL) questionnaires, pain and anxiety scores, and an objective “gummy jelly” chewing test were carried out at multiple timepoints, along with detailed health economics information. Implants were placed one-stage, and an early loading protocol was utilised. Patients were reviewed 8 weeks post-placement, and finally at 6 months. Implant failure, recruitment and retention rates were recorded and analysed.ResultsThe pilot study demonstrated that it is possible to recruit, randomise and retain edentulous (mainly elderly) patients for an implant trial. We recruited to target and retention rates were acceptable. The large number of questionnaires was onerous for participants to complete, but the distribution of scores and feedback from participants helped inform the choice of primary and secondary outcomes in a full trial. The chewing test was time-consuming and inconsistent. Implant failure rate was low (1/46). The data on indirect costs gathered at every visit was viewed as repetitive and unnecessary, as there was little or no change between visits.ConclusionsThe pilot study has shown that acceptable recruitment and retention rates are achievable in this population of patients for this intervention. The results provide valuable information for selection of outcome variables and sample size calculations for future trials.Trial registration(ISRCTN): 87342238 Trial registration date: 05/07/2013.Electronic supplementary materialThe online version of this article (doi:10.1186/s12903-017-0333-1) contains supplementary material, which is available to authorized users.

Mini‐implants and narrow diameter implants as mandibular overdenture retainers: A systematic review and meta‐analysis of clinical and radiographic outcomes

“…The selected studies were divided into two groups, one with studies using MI (n = 24) and another using NDI (n = 12). The MI group consists of 1 cross‐sectional clinical study, three retrospective longitudinal clinical studies, 13 prospective longitudinal clinical studies and seven randomised clinical trials . Eight studies used conventional loading, 13 used immediate loading, two studies used both loading types, and one study did not report this information .…”

“…The MI group consists of 1 cross‐sectional clinical study, three retrospective longitudinal clinical studies, 13 prospective longitudinal clinical studies and seven randomised clinical trials . Eight studies used conventional loading, 13 used immediate loading, two studies used both loading types, and one study did not report this information . One study used bar attachments, one study locator attachments, 19 studies used ball attachments, and three studies used bar and ball attachments .…”

“…Eight studies used conventional loading, 13 used immediate loading, two studies used both loading types, and one study did not report this information . One study used bar attachments, one study locator attachments, 19 studies used ball attachments, and three studies used bar and ball attachments . The NDI group comprises three retrospective longitudinal clinical studies, six prospective longitudinal clinical studies and three randomised clinical trials .…”

“…The methodological quality of the studies was evaluated and classified separately, and the results are listed in Table . Of the 24 MI studies, 12 were classified as poor, 10 as fair and two were classified as good . Of the 12 NDI studies, two were classified as poor, seven were classified as fair, and three were classified as good .…”

“…The MI group consists of 1 cross-sectional clinical study, 42 42,45 and one study did not report this information. 48 One study used bar attachments, 56 one study locator attachments, 46 19 studies used ball attachments, 21,22,25,28,31,[42][43][44][45][47][48][49][50][51][52][53][54][55]58 and three studies used bar and ball attachments. 27,35,57 The NDI group comprises three retrospective longitudinal clinical studies, 29,36,59 six prospective longitudinal clinical studies 12,23,24,60-62 and three randomised clinical trials.…”