Wettability of three denture base materials to human saliva, saliva substitute, and distilled water: A comparative in vitro study

The wettability of complete denture base materials constructed by conventional versus digital techniques: an in-vitro study

BACKGROUND

Decreased salivary flow can make the patients uncomfortable with their complete dentures and affects the retention of the dentures. Milling and 3D printing have become an alternative to conventional denture construction techniques. The goal of this study was to evaluate the effect of conventional and digital techniques of the complete denture construction on the denture surface wettability with distilled water and saliva substitute before and after thermocycling.

METHODS

A total of 30 specimens were utilized in the present study. Specimens were divided according to the construction techniques into 3 groups (n = 10 each). Group I: Heat-polymerized polymethylmethacrylate (PMMA) group, group II: Milled group, and group III: 3-dimensional (3D)-printed group. All the specimens were subjected to 2000 cycles of thermal aging in a thermocycler. The wettability of all specimens to water and saliva substitute was measured via a contact angle goniometer (Olympus TGHM, Rame-hart Inc, USA) before and after thermocycling. Descriptive statistical analysis, plots, and the Shapiro-Wilk test were used to verify normality for each variable. One-way ANOVA was used to compare the 3 study groups, while paired samples t-test was used to compare the differences within each group (P < .05).

RESULTS

The smallest contact angle of drop of water to the denture base specimens before and after thermocycling were recorded in the milled group (53.0 ± 4.77 and 50.27 ± 2.30, respectively), followed by the heat polymerized PMMA group (85.65 ± 4.71 and 65.06 ± 2.27, respectively), and the 3D-printed group (91.34 ± 6.74 and 90.86 ± 8.57, respectively). While the smallest contact angle of drop of saliva substitute to denture base specimens was recorded in the milled group (56.82 ± 2.29 and 34.85 ± 7.51, respectively), followed by the 3D-printed group (72.87 ± 4.83 and 58.14 ± 9.58, respectively) and the heat polymerized PMMA group (83.62 ± 4.12 and 67.82 ± 4.93, respectively). There was statistically significant difference between the groups (P < .05). A significant decline in the average contact angle of drop of saliva has been reported in all groups after thermocycling. The contact angle values differed significantly between saliva substitute and distilled water in both 3D-printed and milled groups after thermocycling (P < .001).

CONCLUSIONS

The milled denture base material presented the best wettability to water and saliva substitute than the 3D-printed and the heat-polymerized PMMA materials. Saliva substitutes improve the wetting ability of denture base materials manufactured by CAD/CAM compared with water.

Characterization of nanoceria-modified silicone soft liners: Surface morphology, hardness, wettability, cytotoxicity, and antifungal properties in artificial saliva - An in vitro study

Statement of problem

Soft liners are essential for denture wearers, which aids in the healing of soft tissue injuries caused by rough denture base surfaces. Silicone soft liners, while effective, can accumulate biofilm over time, necessitating enhancement.

Purpose

This in vitro study aimed to assess the efficacy of silicone soft liners incorporating varying concentrations of cerium oxide nanoparticles.

Materials and methods

A stainless-steel die as per ISO standard 10139-2-2018 (35 × 6 mm), Using G*Power 3.0.10 software, 400 samples were prepared with 95 % confidence interval and 80 % power. Samples were divided into five groups: surface morphology (Group A), surface hardness (Group B), wettability (Group C), cytotoxicity (Group D), and antifungal property (Group E). Each group was subdivided based on cerium oxide nanoparticle concentrations. Samples were stored in artificial saliva until evaluation. Surface morphology was examined via scanning electron microscopy (SEM), surface hardness using Shore A Durometer, wettability by drop shape analysis, cytotoxicity via MTT assay, and antifungal properties using crystal violet staining.Data were assessed for normal distribution using Kolmogorov-Smirnov and Shapiro-Wilk tests.

Results

SEM analysis showed optimal nanoparticle dispersion in Group A2(0.25 %) and A3 (0.5 %). Group B2 (0.25 %) exhibited the lowest mean surface hardness, decreasing from day 1 to day 30. Group C3 demonstrated the most hydrophobic surface across days. Group D2 exhibited the least cytotoxicity at all time intervals. Group E4 displayed the highest antifungal activity.

Conclusion

Within study limitations, silicone soft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles exhibited superior properties in surface hardness and cytotoxicity. Optimal surface morphology and wettability were observed with 0.5 % concentration, while antifungal efficacy peaked at 1 %. These findings suggest clinical potential for treating damaged oral tissues.

Clinical implications

Soft liners modified with 0.25 % and 0.5 % cerium oxide nanoparticles may benefit patients with oral tissue abuse, offering enhanced therapeutic properties.

Evaluation and assessment of the wettabilty and water contact angle of modified poly methyl methacrylate denture base materials against PEEK in cast partial denture framework: an in vitro study

INTRODUCTION

The prevalence of adults with partially dental arches is expected to be more than imagined and patients requiring replacement of missing teeth are slowly increasing in number too. Removable partial dentures are known to provide for substantial replacement for the missing teeth with also added advantages when compared to fixed or implant prosthesis, mainly in elderly patients. Denture base material performance and durability are greatly influenced by wettability and water contact angle. In the case of dentures; adequate moisture distribution is necessary to ensure excellent wettability which has an influence on comfort and oral health. The purpose of conducting this study was to find out whether the advancements made using PEEK (Polyether ether ketone) would prove to be more beneficial than the current upgrades in the current material spectrum.

MATERIALS AND METHODS

This study was performed under in vitro conditions. All the fabrication and processing was done only by one operator. The materials used were divided into three groups each comprising 20 samples. Group A was modified polymethylmethacrylate (Bredent Polyan), Group B was polyoxymethylene acetal resin (Biodentaplast) and Group C was PEEK. An Ossila Goniometer was used to measure the contact angle. The three types of liquids used for the testing included distilled water, natural saliva and mouth wetting solution (Wet Mouth Liquid, ICPA India). Human saliva was collected from an individual with no medical conditions and normal salivary secretion.

RESULTS

The data was analyzed using One-way ANOVA test and a pairwise comparison using the Post Hoc Tukey's Honest Significant Difference. Table 1 consists of the mean water contact angles of the denture base materials and mean contact angles of various denture base materials. In saliva, mouth wetting solution and distilled water, the highest mean and least mean contact angle was seen in Polyan and Biodentaplast respectively. A signicant difference was seen between PEEK and Polyan and Biodentaplast and Polyan on further comparison.

CONCLUSION

From the resources and the materials at our disposal, it could be concluded that Polyan, Biodentaplast and PEEK and could be used as viable options in cast partial denture framework.

Evaluation of surface energy and surface stability and adherence of Candida albicans to octa fluoro pentyl (meth) acrylate-coated PEEK using plasma spray

Background

Polyetheretherketone (PEEK) has favorable properties that make it able to be used as a denture base material, but it is also susceptible to the adhesion of microorganisms. In this study, we applied Octafluoropentyl (meth) acrylate (OFPA) coating on the PEEK polymer surface by using plasma spray and investigated the functional groups present on the surface, changes in the surface energy and Candida albicans adhesion.

Materials and Methods

In this experimental study, the samples were placed in a control group without surface preparation and three experimental groups that were subjected to plasma spray for 10, 30, and 60 s and then impregnated with degassed Octa fluoropentyl (meth) acrylate (Sigma-Aldrich, USA) monomer. Fourier transform infrared spectroscopy (FTIR) was used to identify the functional groups and new chemical bonds between PEEK and OFPA, and Sessile Drop Method was used to evaluate the surface's wettability. The surface morphology was checked using a LEXT OLS4000 (Olympus®-Japan) microscope, and the inhibition of C. albicans adhesion was also checked by counting the colonies in terms of colony forming unit/mL (CFU/mL). Kurskal-Wallis analysis was conducted to assess Candida adhesion, while wettability was evaluated using analysis of variance and post hoc analyses. The level of statistical significance was set at P < 0.05.

Results

FTIR analysis confirmed that a chemical between OFPA and PEEK was established. The samples showed a significant increase in the contact angle after 30 s of plasma application (CA = 88.2 ± 7.3). The contact angle decreased again by increasing the surface modification to 60 s (CA = 64.33 ± 5.5). Examining the surface morphology of the samples shows an increase in surface roughness with increasing plasma time up to 60 s. The number of adherent colonies was the lowest in 30 s group, but it was not statistically significant (P = 0.658).

Conclusion

No statistically significant difference in C. albicans CFU/mL count was found between groups. The contact angle of the 30 s group was significantly higher than the control group.

Prosthodontic implications of saliva and salivary gland dysfunction

PURPOSE

To provide a detailed overview of the fundamentals of saliva constituents and production. The review outlines the clinical manifestations as a consequence of salivary gland dysfunction and management strategies for patients with salivary gland dysfunction. Prosthodontic implications of saliva and salivary gland dysfunction are presented.

MATERIALS AND METHODS

English-language literature relating to saliva constituents, physiologic saliva production, clinical manifestations secondary to salivary gland dysfunction, salivary biomarkers, and management strategies were retrieved via electronic search. Relevant articles were summarized for this manuscript with a view toward providing pragmatic information.

RESULTS

Saliva is produced by three pairs of major and minor salivary glands. The major salivary glands, namely, the parotid, submandibular, and sublingual glands, contribute approximately 90% of saliva production. Saliva contains serous and mucinous secretions produced by different types of cells within salivary glands. Parasympathetic and sympathetic fibers innervate the major salivary glands, and upon stimulation, the parasympathetic innervation increases serous secretions, while the sympathetic innervation increases protein secretion. Stimulated saliva is mainly derived from the parotid glands which are composed of serous acini, while unstimulated saliva is mainly derived from the submandibular glands which are composed of mixed seromucous acini. As major salivary glands contribute the most to salivary flow, local or systemic factors influencing those glands can disrupt saliva production resulting in clinically significant oral manifestations.

CONCLUSION

This review provides a fundamental overview of saliva production. In addition, the review highlights the various clinical manifestations secondary to salivary gland dysfunction, explores salivary biomarkers for screening of systemic diseases, discusses management strategies for patients with salivary gland dysfunction, and outlines the prosthodontic implications of saliva and salivary gland dysfunction.

Assessment of Zinc-Bound Phosphate-Based Glass-Coated Denture-Relining Material with Antifungal Efficacy for Inhibiting Denture Stomatitis

This study investigated the surface properties, biocompatibility, and antifungal activity against Candida albicans of a denture-relining material coated with zinc-bound phosphate-based glass. First, zinc-bound phosphate-based glass was fabricated. A polymerized denture-relining disk was coated with zinc-bound phosphate-based glass (2%, 4%, and 6%). The surface properties of the control and experimental groups were measured, including the wettability, microhardness, color difference, and gloss. The biocompatibility was evaluated using the MTT assay according to ISO 10993-5. The antifungal activity was investigated by counting the number of colony-forming units of Candida albicans. The results were analyzed using a one-way ANOVA and Tukey's test (p = 0.05). The results of this study indicate that, despite the antimicrobial effect of zinc-bound phosphate-based glass, a coated denture-relining material does not degrade the surface properties and biocompatibility. Therefore, this novel material is considered promising for use as a dental material with antimicrobial properties that can potentially prevent denture stomatitis.