Influence of Light-Curing Glaze and Chlorhexidine Gluconate in the Acrylic Resin Properties: An in situ Study.

This in-situ study aimed to evaluate the chromatic stability, microhardness, and surfacefree energy of chemically activated acrylic resin (CAAR) samples. Eighty CAAR samples were made and each volunteer (n = 20) received two palatal plates with two sides of groups (without and with glaze application). The samples were exposed to two conditions: the control condition (sucrose 30%) and the test condition (sucrose 30% and 0.12% chlorhexidine). The volunteers used the first palatal device (control condition) for seven days and the second palatal device (test condition) for another seven days, with a seven-day break between them. Then, the ΔΕ00, microhardness, and surface-free energy tests were performed. Analysis of Variance and the Tukey test were used (α = 0.05). The control group with glaze showed higher ΔΕ00 compared to the group without the glaze. The test group with glaze had less ΔΕ00 than their respective controls. In both periods, when the glaze was applied, higher microhardness values were found for all groups. Groups with glaze showed lower roughness and higher surface-free energy than groups without the glaze. The values obtained in this study were satisfactory, showing the clinical efficacy of glaze and the use of 0.12% CH for maintaining the physical and mechanical properties of CAAR.

Effect of photopolymerized glaze application on bacterial adhesion on ocular acrylic resin surfaces submitted to accelerated ageing.

Conditions of the acrylic resin (AR) surface, such as roughness, can promote a favourable environment for the adhesion of micro-organisms, even on the surface of ocular prostheses. This study evaluated the influence of photopolymerized glaze application on the roughness of ARs and adhesion of Staphylococcus aureus and Staphylococcus epidermidis on ocular AR surfaces submitted to accelerated ageing. Two hundred and eighty-eight samples of white colour (N1) and colourless ARs were distributed in eight groups (n = 9), based on surface treatments (glaze or ARs submitted to only a final polishing), accelerated ageing (before and after) and periods of microbial growth (24- and 48-h). The roughness average (Ra) and total height of roughness profile (Rt) values were greater for the groups with glaze and increased for all groups after ageing. The microbial adhesion among the groups with and without glaze did not present a statistically significant difference. The ageing did not statistically affect the adhesion of Staph. epidermidis, but affected the adhesion of Staph. aureus, which presented an increase after 24 h of growth on only N1 AR with glaze. These results demonstrate that the glaze did not contribute to adhesion of Staph. aureus and Staph. epidermidis, which are responsible for most ocular prosthetic infections. SIGNIFICANCE AND IMPACT OF THE STUDY: Some recent evidence suggested that the surface finish of ocular prostheses influences the accumulation of deposits that can affect the interaction with pathogenic bacteria, increasing the probability of infections. In addition, surface deterioration over time can increase the roughness and, consequently, biofilm formation. Thus, a better understanding of the influence of surface finish on bacterial adhesion becomes extremely important. In this study, we tested a glaze for surface polishing compared to mechanical polishing, before and after ageing. The results suggest that the glaze did not contribute to microbial adhesion and might be useful in preventing possible prosthetic infections.

Oral rehabilitation of patients after maxillectomy. A systematic review.

Patients who have maxillectomy can be rehabilitated with reconstructive surgery or obturator prostheses with or without osseointegratable implants. To identify studies on possible treatments in this group, we systematically searched the Scopus, Embase, PubMed/Medline, and Cochrane databases to collect data on patients' characteristics, radiotherapy, and results related to speech, swallowing, mastication or diet, chewing, aesthetics, and quality of life. Of the 1376 papers found, six were included, and one other was included after an additional search of references. A total of 252 patients were included, and of them, 86 had reconstructive surgery, 91 were treated with obturator prostheses, 39 had reconstructive surgery or obturator prostheses associated with implants, and 36 had reconstruction plus an obturator prosthesis. Data on radiotherapy were incomplete. There is a lack of consensus about the indication for rehabilitation, as the treatment must be based on the individual characteristics of each patient.