Effects of Overnight Storage Conditions on Conventional Complete Dentures

Objectives: In order to prevent general and oral health problems, it has been advocated to remove dentures during sleep and to store them dry, or in a wet environment with a cleansing tablet. We investigated the effects of these environments on the dimensional stability, retention, and patient related outcome measures.
Methods: This study was granted ethics approval (CCER No: 2017-02030). Subjects with upper conventional complete removable prostheses (CRPs) were randomly assigned to receive two interventions in a cross-over design: storing the CRPs overnight in a dry environment and in a wet environment with a cleansing tablet. Outcome measures were collected before each intervention (BLN), post intervention (PIS) and after immersion in water for 15 min after the intervention (WOC). Dimensional changes were analysed using a surface comparison software (OraCheck). The analysis was performed for the total surface, anterior flange, palate, and tuberosities. Retention force was measured using a dynamometer and the participants’ subjective assessment of the comfort, fit and retention of their CRPs were collected. Statistical analysis include verifying normal distribution using the Kolmogorov-Smirnov test, after which paired T-tests and non-parametric Wilcoxon signed-rank tests were used to check for any statistical significance between the tested interventions (alpha=0.05)
Results: Ten participants (mean age: 76.5±5.9y) were recruited in this study. Between BLN and PIS the dimensional changes after dry intervention were significantly less than when stored wet for total surface (p=0.009), anterior flange (p=0.028), and the palate (p=0.005). No difference was found between the effects of storage or washout interventions on objectively measured CRP retention. However, after WOC following dry storage, participants perceived a lower retention (p=0.021), and a more comfortable palate after WOC following the wet intervention (p=0.018).
Conclusions: Dry overnight storage of CRPs often accused to cause warping, can safely be recommended and is not a risk factor for denture deformation.