Mandibular implant-supported overdentures and oral function.

OBJECTIVES: Oral rehabilitation by means of implant-retained mandibular overdentures is known to improve oral function. The aim of this study was to evaluate the long-term effects of mandibular implant treatment on oral function. We quantified maximum bite force and masticatory performance 10 years after implant treatment. It was hypothesized that these outcome measures would not change in this period. MATERIALS AND METHODS: Eighteen edentulous patients were scheduled for re-evaluation of their oral function 10 years after they had participated in a randomized cross-over clinical trial. In that trial, they had received two mandibular implants and a new denture with successively magnet-, ball-socket, and bar-clip attachments. RESULTS: At the 10-year follow-up, 14 of the initial 18 patients participated in the evaluation. As a result of the implant treatment, the average maximum bite force more than doubled, from 162 to 341 N, whereas the average number of chewing cycles to halve the initial particle size decreased from 55 to 27 cycles. No significant changes in maximum bite force and masticatory performance were observed after 10 years. However, the average maximum bite force obtained with implant-retained overdentures is still significantly lower than that of dentate subjects (569 N). CONCLUSION: Maximum bite force and masticatory performance significantly increased after implant treatment and remained unaltered during the following 10-year period. Thus, implant treatment greatly improves oral function for a long period of time.

[Patient satisfaction with different types of implant-retained overdentures in the edentate mandible]. / Patiënttevredenheid met verschillende mesostructuren op implantaten in de edentate onderkaak.

The purpose of this study was to determine patient satisfaction with implant supported mandibular overdentures using magnet, bar-clip and ball-socket attachments, and to assess the relation between maximum bite force and patient satisfaction. In a crossover clinical trial, 18 edentulous patients with lower denture complaints received 2 mandibular implants and new lower and upper dentures. The lower denture initially came without any kind of attachment system, but was fitted with one of the attachment types after 3 months. The attachments were changed 3 months thereafter, in random order. A questionnaire concerning denture complaints was given at baseline (with the old denture), after 3 months of functioning with the new denture without attachments and after 3 months of functioning with each of the attachments (within-subject comparison). In addition, at the end of the experiment patients were asked to express their overall satisfaction with their dentures on a visual analogue scale (VAS). Data regarding maximum bite force were obtained from a previous study with the same population. Mandibular implant supported overdenture treatment reduced various denture complaints. The VAS score reflected patients' preference more accurately than scale-scores. Patients strongly preferred bar-clip (10 subjects) and ball-socket attachments (7 subjects) over magnet attachments (1 subject). Patients' preference could not be predicted on the basis of baseline observations. Maximum bite force was not correlated to scale- or VAS scores.

The influence of various attachment types in mandibular implant-retained overdentures on maximum bite force and EMG.

The type of attachment that is used in oral rehabilitation by means of implant-retained mandibular overdentures may influence the retention and the stability of the denture. In this study, we examined the hypothesis that a better retention and stability of the denture improve the oral function. Eighteen edentulous subjects received 2 permucosal implants, a new denture, and, successively, 3 suprastructure modalities. Maximum bite force and electrical activity of the masseter and temporalis muscles were measured. The maximum bite force nearly doubled after treatment for each of the 3 attachments. However, the average bite force after treatment was still only two-thirds of the value obtained for dentate subjects. No large differences in maximum bite force and muscle activity were found among the 3 attachment types. Temporalis activity was significantly lower than masseter activity when subjects clenched without implant support. There was no difference in activity when subjects clenched with implant support.

Masticatory function with implant-supported overdentures.

The type of attachment that is used in implant-supported mandibular overdentures may influence the retention and stability of the prosthesis and, thus, masticatory function. In this within-subject cross-over clinical trial, we examined the hypothesis that greater retention and stability of the overdenture improve the masticatory function. Eighteen edentulous subjects received 2 oral implants, a new overdenture, and, successively, 3 different suprastructure modalities: magnet, ball, and bar-clip. Masticatory performance, masticatory efficiency, and swallowing threshold were measured. The masticatory function significantly improved after implant treatment with each of the 3 attachments. We observed small differences in masticatory function among the 3 attachment types: slightly better masticatory performance with ball and bar-clip than with magnet attachments. The number of chewing cycles until swallowing hardly decreased after implant treatment. We conclude that significantly better masticatory performance, combined with a slightly smaller number of chewing cycles after implant treatment, results in smaller food particles being swallowed.