Design A randomised controlled trial (RCT) was carried out involving dental hospital patients. Intervention The implant group (IG) were provided with conventional maxillary dentures and implant-retained mandibular overdentures and the denture group (DG) were provided with conventional dentures. Patients consumed seven test foods. Outcome measure Pre-and post-treatment questionnaires were completed relating to food choices and chewing difficulty. Results IG subjects reported increased consumption of carrots, apples and nuts post-treatment (P<0.05) and decreased post-treatment difficulty in chewing apples and nuts. DG subjects reported decreased post-treatment difficulty in chewing carrots, bacon and nuts (P<0.05). Between-group differences for chewing difficulty were detected for nuts, which DG subjects found easier to chew than did IG subjects (P=0.002). Conclusions Food selection and perceived chewing difficulty improved in both groups, with no significant differences between groups. Successful rehabilitation may not result in different food selection, which may require concurrent tailored dietary interventions, but may increase available food choices.
CommentaryThis is the second RCT by these authors, dealing with more or less the same subject as their first paper 1 but with a somewhat different purpose. This was clearly and eloquently stated: to assess the impact of implant-retained overdentures on the food selection of edentulous adults.The inclusion and exclusion criteria of the participants were reasonably inclusive, although it would have been better to base the selection on the level of bone resorption rather than the duration of edentulousness. The randomisation process was well-defined and properly conducted. A power calculation was carried out to find the number of patients needed to detect differences between the groups. The study used the appropriate statistical tests for significance of changes to evaluate the before and after effects of the intervention.Although the lack of masking (blinding) of both patients and providers might appear to be a negative property of the RCT, it is virtually impossible, in studies of this type, to mask the patient or the provider from the type of denture provided. A real negative, however, is that it is not clear what exactly the patients gave consent for: according to the authors, neither group was "aware of the other arm of the study": the participants did not consent to having implants and were not fully informed of the nature of the study. This is also demonstrated by the fact that some patients in the IG refused the implant option after being randomly allocated to the group. To these patients, the intention-to-treat analysis (ITT) was applied. This was a good choice by the authors since ITT is typically applied to a group whose participants deviated from the treatment or were lost to followup. ITT should have also been applied, though, to the "five patients from the IG and the nine from the denture group" who were lost to followup at 3 months.As described earlie...