Effect of denture adhesive on retention of the mandibular and maxillary dentures during function.

The purpose of this study was to determine the effect of denture adhesive on retention of mandibular and maxillary dentures over a four-hour period. Denture movements were measured using an alternating magnetic field tracking device that determines the position of magnetic receiver coils relative to a transmitter coil positioned over the head. Ten adults with complete maxillary dentures and complete mandibular implant overdentures were enrolled in the study. Specially fabricated mandibular dentures contained a relief area that exposed the implant post which no longer anchored the denture, but now served as an attachment point for a receiver coil that measured mandibular movement. The denture coil was attached lateral to the post coil on a shelf cut into the denture. Mandibular denture movements were recorded as the difference between the mandible movement signal and the mandible + mandibular denture signals. Measurements of denture movements were made at baseline (no adhesive) and at 0, 2, 4 hours post-adhesive application with Fixodent cream for standardized chewing and biting. The MoveTrack signals were recorded on a digital data cassette recorder for subsequent computer analysis. The results of the measurements were analyzed using paired sample t-tests. Specifically, the following comparisons of movement means were made: mandibular vs. maxillary, baseline vs. post-baseline and successive changes (e.g., baseline vs. hour 0, hour 0 vs. hour 2, etc.). Results of these analyses showed that: 1) mandibular denture movements under both adhesive and non-adhesive conditions were significantly greater than maxillary denture movements; 2) the adhesive significantly reduced movement of the maxillary and mandibular dentures during both chewing and biting; and 3) the improvement occurred immediately post-application of the adhesive and was maintained for the four hours of follow-up.