Assessment of Children and "Young" Adult Patients' Quality of Life after Prosthetic Treatment of Disorders of the Craniofacial Region-A Retrospective Study.

BACKGROUND: Prosthetic rehabilitation for children and juvenile patients with congenital or acquired craniofacial disorders is the area of activity of many clinicians and is a major diagnostic and therapeutic challenge for dentists. METHODS: Studies were carried out on a group of 30 patients (10 female and 20 male) aged 2.5 to 30 years who were treated prosthetically due to congenital and acquired craniofacial disorders. The aim of this study was to assess the quality of life using the CPQ 11-14 (Child Perception Questionnaire 11-14), OQLQ (Orthognathic Quality of Life Questionnaire), and PIDAQ (Psychosocial Impact of Dental Aesthetics Questionnaire). RESULTS: Before the prosthetic treatments, the mean values in the individual questionnaires were, respectively, CPQ 11-14-54 points; OQLQ-44.4 points; and PIDAQ-47.6 points. The following values were obtained after the treatments: CPQ 11-14-12.43 points; OQLQ-22.27 points; and PIDAQ-34.03 points. All obtained differences were statistically significant. CONCLUSIONS: The total numerical results obtained in all questionnaires decreased, which means that prosthetic rehabilitation had a positive impact on the assessment of the quality of life based on individual categories.

Color Stability of Zinc Oxide Poly(methyl methacrylate) Nanocomposite-A New Biomaterial for Denture Bases.

(1) Background: The purpose of this in vitro study was to evaluate the color change and stability of a zinc oxide nanoparticle-poly(methyl methacrylate) (ZnO NP-PMMA) nanocomposite for denture base material after immersion in different dietary and cleaning agent solutions. (2) Methods: One hundred samples were prepared and divided into four equinumerous groups depending on the weight content of ZnO NPs. The color coordinates (CIE L*a*b*) were measured using a digital colorimeter, ColorReader (Datacolor AG Europe, Rotkreuz, Switzerland), before and after immersion of the specimens in five different solutions (distilled water, coffee, red wine, black tea, denture cleaning tablet solution) for 6 months. The color changes (ΔE) were calculated using Euclidean distance and analyzed by the Shapiro-Wilk test and the ANOVA/Kruskal-Wallis multiple comparison and adequate post hoc tests. (3) Results: All tested materials showed significant color changes after their exposure to all solutions. Color changes were greatest in the case of red wine and progressed with the duration of the study. (4) Conclusions: The modification of PMMA with ZnO nanoparticles is acceptable in aesthetic terms in 2.5% and 5% weight content; however, color changes are more noticeable with higher nanoparticle content and must be discussed with the patient prior to possible use.

Comparison of Mechanical Properties of a Self-Adhesive Composite Cement and a Heated Composite Material.

(1) Background: Due to the limitations of composite cements, the authors carried out tests to compare such materials with preheated composite materials because the latter may be an alternative to cements in the adhesive cementation procedure. (2) Methods: The materials used in the adhesive cementation procedure, i.e., Enamel Plus Hri (Micerium, Avegno, Italy), a heated composite material, and RelyX U200 Automix (3M, Maplewood, MN, USA), a dual composite cement, were tested for microhardness, compressive strength, flexural strength, diametral compressive strength, and elastic modulus. Composite material was heated to the temperature of 50 degrees Celsius before polymerisation. (3) Results: Higher values of microhardness (by 67.36%), compressive strength (by 41.84%), elastic modulus (by 17.75%), flexural strength (by 36.03%), and diametral compressive strength (by 45.52%) were obtained using the Enamel Plus Hri composite material compared to the RelyX U200 self-adhesive cement. The survey results revealed statistically significant differences. (4) Conclusions: Due to its better mechanical properties, the heated composite material (Enamel Plus Hri) is a beneficial alternative to composite cements in the indirect restoration placement procedure. As the strength parameters of the heated composite material increase, a higher resistance to the compressive and bending forces present in the oral cavity, and hence a greater durability of the created prosthetic reconstructions can be expected.

Preparation and Characterisation of Poly(methyl metacrylate)-Titanium Dioxide Nanocomposites for Denture Bases.

Introduction of titanium dioxide nanoparticles (TiO2 NPs) to poly(methyl methacrylate) (PMMA) aims to improve the mechanical, microbiological and tribological properties of dental prosthesis bases. The aim of the research was to assess the polymerisation time and the change in the colour of the new biomaterial. Samples with the 1 wt% and 2 wt% content of TiO2 additionally modified by ultrasounds were created. The effectiveness of ultrasounds was assessed by comparing the average size of conglomerates in a liquid acrylic resin monomer by means of a dynamic light scattering (DLS) analysis. The biomaterial structure was assessed by the energy-dispersive X-ray spectroscopy (EDS) analysis. The colour change was analysed by means of a colorimetric test and provided in the CIE (Commission internationale de l'éclairage) L*a*b* and RGB (Red Green Blue) colour palette. It was observed during the DLS test that the ultrasonic homogenisation process caused an increase in the suspension heterogeneity. The EDS analysis confirmed the presence of nanoparticles sized below 100 nm, which constitutes a ground for calling the new biomaterial a nanocomposite. The addition of TiO2 NPs as well as the ultrasounds result in the reduction of the average PMMA polymerisation time. The obtained data reveal that the addition of both 1 wt% and 2 wt% causes a considerable change in the PMMA colour: its whitening. To summarise, the reduced polymerisation time of the new biomaterial fully enables performance of standard procedures related to creation of dental prosthesis bases. Due to the considerable change in the colour, the clinical application is limited to performance of repairs or relining of the prosthesis, where the new material is located in an unaesthetic zone.

Zinc Oxide Nanoparticles Cytotoxicity and Release from Newly Formed PMMA-ZnO Nanocomposites Designed for Denture Bases.

The goal of the study was to investigate the level of zinc oxide nanoparticles (ZnO NPs) release from polymethyl methacrylate (PMMA)-ZnO nanocomposites (2.5%, 5%, and 7.5% w/w), as well as from the ZnO NPs layer produced on pure PMMA, and the impact of the achieved final ZnO NPs concentration on cytotoxicity, before the potential use as an alternative material for denture bases. The concentration of ZnO nanoparticles released to the aqueous solution of Zn2+ ions was assessed using optical emission spectrometry with inductively coupled plasma (ICP-OES). In the control group (pure PMMA), the released mean for ZnO was 0.074 mg/L and for individual nanocomposites at concentrations of 2.5%, 5%, and 7.5% was 2.281 mg/L, 2.143 mg/L, and 3.512 mg/L, respectively. The median for the ZnO NPs layer produced on PMMA was 4.878 mg/L. In addition, in vitro cytotoxicity of ZnO NPs against the human HeLa cell line was determined through the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) dye. The cytotoxicity studies demonstrate that ZnO nanoparticles in the concentrations up to 20 mg/L have no adverse effect on HeLa cells. When compared with the released and cytotoxic concentrations of ZnO NPs, it can be expected that ZnO released from dental prostheses to the oral cavity environment will have no cytotoxic effect on host cells.

Mechanical and Physicochemical Properties of Newly Formed ZnO-PMMA Nanocomposites for Denture Bases.

AIM: The aim of this study was to investigate the selected properties of zinc oxide- polymethyl methacrylate (ZnO-PMMA) nanocomposites that can influence the microorganism deposition on their surface. MATERIALS AND METHODS: Non-commercial ZnO-NPs were prepared, characterized and used for the preparation of PMMA nanocomposite. Roughness, absorbability, contact angle and hardness of this new nanomaterial were evaluated. PMMA without ZnO-NPs served as control. OUTCOMES: Compared to unenriched PMMA, incorporation of ZnO-NPs to 7.5% for PMMA nanocomposite increases the hardness (by 5.92%) and the hydrophilicity. After modification of the material with zinc oxide nanoparticles the roughness parameter did not change. All tested materials showed absorption within the range of 1.82 to 2.03%, which meets the requirements of International Organization for Standardization (ISO) standards for denture base polymers. CONCLUSIONS: The results showed no significant deterioration in the properties of acrylic resin that could disqualify the nanocomposite for clinical use. Increased hydrophilicity and hardness with absorbability within the normal range can explain the reduced microorganism growth on the denture base, as has been proven in a previous study.

Preparation and characterization of ZnO-PMMA resin nanocomposites for denture bases.

PURPOSE: The aim of the paper was to investigate the antifungal activity of zinc oxide nanoparticles (ZnONPs) against Candida albicans. Some attempts have been made to find out the best way to introduce ZnONPs into polymethyl methacrylate (PMMA) resin material and to determine some parameters of a newly formed composite. MATERIAL AND METHODS: Zinc oxide nanoparticles were manufactured and their basic physical parameters were determined (average particle size, density, specific surface area). Minimal inhibitory concentration (MIC) of ZnONPs was determined for the Candida albicans standard strain. The average size of ZnO conglomerates in the monomer solution of PMMA resin was measured using a dynamic light scattering instrument. PMMA resin samples with incorporated ZnONPs were produced. The morphology of nanopowder and the newly formed composite was examined under a scanning electron microscope (SEM). In addition, the roughness parameter of PMMA resin material was investigated before and after ZnONPs modification. RESULTS: Nanopowder with the average particle size of 30 nm, density of 5.24 g/cm3 and surface area of 39 m2/g was obtained. MIC was determined at the level of 0.75 mg/mL. The average size of ZnO conglomerates in the monomer solution of acrylic resin dropped by 11 times after ultrasound activation. SEM examination of a newly formed composite showed a successful introduction of ZnONPs confirmed by the energy dispersive X-ray spectroscopy (EDS) analysis. There were no statistically significant differences in the biomaterial roughness before and after the modification of ZnONPs. CONCLUSION: Zinc oxide nanoparticles were successfully incorporated into acrylic resin used for the production of denture bases. The presence of nanoparticles with sizes below 100 nm was confirmed. Nevertheless a newly created composite needs to be further investigated to improve its homogeneity, and to check its microbiological properties, strength and biocompatibility prior to its possible clinical use.

Significance of polymethylmethacrylate (PMMA) modification by zinc oxide nanoparticles for fungal biofilm formation.

The objective of this study was to obtain a material composite with antifungal properties for dentures to be used as an alternative protocol in denture stomatitis treatment and prevention. Denture stomatitis is still a clinical problem in patients particularly vulnerable to this disease. Composites of PMMA and doped ZnO-NPs (weight concentrations, 2.5%, 5%, 7.5%) and PMMA with sprayed solvothermal and hydrothermal ZnO-NPs were tested. The following investigations of newly formed biomaterials were undertaken: influence on Candida albicans solution, biofilm staining, XTT analysis and a quantitative analysis of adhered C. albicans. These studies evidenced the antifungal activity of both nanocomposites PMMA-ZnO-NPs and the efficacy of sputtering of zinc oxide nanoparticles on the PMMA. The study of the biofilm deposition on the surface showed that antifungal properties increase with increasing concentration of ZnO-NPs. The XTT assay in conjunction with testing the turbidity of solutions may indicate the mechanism by which ZnO-NPs exert their effect on the increased induction of antioxidative stress in microorganism cells. The denture base made of the aforesaid materials may play a preventive role in patients susceptible to fungal infections. Based on the results obtained a modified treatment of stomatitis Type II (Newton's classification) complicated by fungal infection was proposed.

A multidisciplinary treatment of patients with craniofacial disorders. Own experience.

Oral rehabilitation of patients with craniofacial disorders is a great challenge and needs a multidisciplinary approach. This is due to the diverse etiology of the disease and severity of changes in tissues and organs. Congenital absence of tooth germs manifested in the form of oligodontia or anodontia, the presence of persistent deciduous teeth in ectodermal dysplasia (ED), cleft lip and hard palate or cancer-induced changes in the tissues of the stomatognathic system are the most common causes of these disorders. The observed abnormalities are responsible for functional disorders of musculo-articular system, speech and chewing. In addition, noticeable adverse changes in the appearance have a huge psychological impact on patients and their well-being. Therefore, the treatment of these medical conditions should begin in childhood and comprise interdisciplinary rehabilitation, involving prosthetics and orthodontics supported by surgery, as well as speech or laryngological therapy. In this paper the interdisciplinary treatment of patients with oral hard and soft tissues disorders during ectodermal dysplasia is discussed. Early oral rehabilitation can restore lost or abnormally shaped tissues and proper functions of the masticatory system. It can also have a positive impact on further physical and psychological development of patients.