Influence of denture surface roughness and host factors on dental calculi formation on dentures: a cross-sectional study

Efficacy of ultrasonic home-care denture cleaning versus conventional denture cleaning: A randomised crossover clinical trial

OBJECTIVE

To compare the efficacy of test (ultrasonic cleaner combined with immersion in denture cleanser solution) and control (immersion in denture cleanser solution followed by conventional brushing) denture cleaning interventions in enhancing denture cleanliness, reducing denture stomatitis, and improving patient satisfaction.

METHODS

A prospective, single-blind, block-randomised, two-period crossover, superiority-controlled clinical trial was conducted of a 3-month intervention. The study design included a pre-intervention period (2 weeks), intervention period one (3 months), washout period (2 weeks), and intervention period two (3 months). A total of 56 community-dwelling elders were block-randomized into either sequence Test/Control or sequence Control/Test. The intervention, period, and carryover effects for the changes in the cleanliness of extensive partial and complete acrylic dentures, denture stomatitis, and changes in patient satisfaction were estimated using Generalized Estimating Equations models.

RESULTS

Percentage plaque area coverage, patient satisfaction, and denture stomatitis were significantly improved for both intervention and control arms after 3 months (P < 0.05). The intervention arm was found to significantly improve denture cleanliness (P < 0.001) and patient satisfaction (P = 0.002) more than the control arm. Denture-wearing habits and denture age were also significantly associated with the changes in denture plaque coverage (P < 0.05). However, the effect of the test intervention on denture stomatitis was not significantly different compared to the control arm (P = 0.284).

CONCLUSION

This study revealed that the test intervention group was significantly more effective than the control group in improving denture cleanliness and patient satisfaction among community-dwelling elders. This test intervention is recommended for maintaining optimum denture hygiene among older adults.

CLINICAL SIGNIFICANCE

Removable dentures can harbor opportunistic pathogens, emphasizing the need for effective denture hygiene intervention using ultrasonic cleaner combined with immersion in denture cleanser solution to eliminate denture biofilm in community-dwelling elders.

An In Vitro Study regarding the Wear of Composite Materials Following the Use of Dental Bleaching Protocols

Composite materials used in dental restorations are considered resistant, long-lasting and aesthetic. As the wear of restorations is an important element in long-term use, the aim of this study was to evaluate the surface condition of nanohybrid and microfilled composite resins, after being subjected to the erosive action of dental bleaching protocols. This paper reflects a comparative study between one nanofilled composite and three microfilled composites used in restorations. For each composite, three sets of samples (under the form of composite discs) were created: a control group, an "office bleach" group with discs bleached with 40% hydrogen peroxide gel, and a "home bleach" group with discs bleached with 16% carbamide peroxide gel. Wear was numerically determined as the trace and the coefficients of friction obtained using a tribometer, the ball-on-disk test method, and two balls: alumina and sapphire. For all composite groups, there were statistically significant differences between the wear corresponding to the control and bleaching groups, for both testing balls. Regarding the composite type, the largest traces were recorded for GC Gradia direct anterior, for all groups, using the alumina ball. In contrast, for the sapphire ball, 3M ESPE Filtek Z550 was characterized by the largest traces. With respect to the friction coefficients, the "office bleach" group recorded the largest values, no matter the composite or the ball type used. The 3M ESPE Valux Plus composite recorded the largest friction coefficients for the alumina ball, and 3M ESPE Filtek Z550 for the sapphire ball. Overall, the "office bleach" group was characterized by higher composite wear, compared to the "home bleach" protocol or control group. Nanofilled composite resins showed superior wear resistance to microfilled resins after undergoing a bleaching protocol.

Quality of Life, Satisfaction, Occlusal Force, and Halitosis after Direct and Indirect Relining of Inferior Complete Dentures

Objective  The aim of this study was to compare the direct relining technique with the indirect relining technique in relation to quality of life, satisfaction with the relining, occlusal force, and halitosis of users of acrylic complete dentures.

Materials and Methods  Twenty bimaxillary edentulous individuals were selected. They had to use the same pair of complete dentures for a minimum of 1 year and a maximum of 5 years. The subjects were randomly divided in groups of direct relining and indirect relining of the inferior denture ( n = 10). Both groups received the same silicone-based relining. The clinical tests verified the quality of life (Oral Health Impact Profile in edentulous individuals), the satisfaction with the relining, the occlusal force, and halitosis. The tests (halitosis and occlusal force) were performed initially (before the relining), immediately after the relining, and 30, 60, 90, and 180 days after the relining. The questionnaires (quality of life and satisfaction with the relining) were performed initially (before the relining), and 30, 60, 90, and 180 days after the relining.

Statistical Analysis  Analysis of variance and the Tukey test were used ( p < 0.05).

Results  There was no statistical difference comparing the two techniques in all the evaluations ( p < 0.05). There was a significant statistical difference for the factor of time in all clinical tests for each relining technique ( p < 0.05). The quality of life and satisfaction with the relining increased significantly 30 days after the relining when compared with the initial time point, for both techniques ( p < 0.05). The occlusal force increased significantly after 90 and 180 days when compared with the initial time point, for both techniques ( p < 0.05). Halitosis decreased significantly immediately after the relining when compared with the initial time point, for both techniques ( p < 0.05).

Conclusion  Independent of the relining technique used, there was an increase in the quality of life, satisfaction with the relining, and occlusal force, as well as a reduction in the level of halitosis. Both techniques generated similar results and therefore can be options in clinical practice.

Effect of educational progressive web application on patient's oral and denture knowledge and hygiene: A randomised controlled trial

This study aimed to evaluate the effect of a novel progressive web application (PWA) on the patient's oral and denture knowledge and hygiene. Fifty-two removable partial denture wearers were randomised to receive education using the PWA, or verbal instructions accompanied by demonstration of hygienic procedures. Changes in the participants' knowledge score, plaque index, gingival index and denture plaque was evaluated during a follow-up period of 3 months. The participants' acceptance of PWA was explored through usage logs and a feedback form. Both groups showed significant improvement in knowledge scores, oral and denture hygiene indices (p < 0.001) after education. The PWA group demonstrated significantly lower gingival index score than control (p = 0.008) at the third month review. In conclusion, there is potential of using mobile application in educating elderly patients and the PWA is a viable option for providing post-denture delivery instructions.

The Effects of Toothbrush Wear on the Surface Roughness and Gloss of Resin Composites with Various Types of Matrices

Objective: To evaluate and compare the surface roughness and gloss of a DMA-free composite and Bis-GMA-free composite with a DMA-based composite before and after toothbrushing simulation. Materials and Methods: Fifteen dimensionally standardised composite specimens of three nano-hybrid resin composites (Tetric EvoCeram, Admira Fusion, and Venus Diamond) were used. Five specimens from each composite were polished and then subjected to a toothbrushing simulator. Surface roughness (Ra) and gloss were measured before toothbrushing and after 5000, 10,000, 15,000, and 20,000 toothbrushing cycles. The data was analysed using 5 × 3 ANOVA to assess surface roughness and gloss values and pairwise comparisons in the form of Tukey post hoc tests were performed to interpret main effects. Results: For all tested materials, surface roughness increased, and gloss decreased after toothbrushing abrasion. Surface roughness (Ra) values ranged from 0.14 to 0.22 μm at baseline and increased to between 0.41 and 0.49 μm after 20,000 toothbrushing cycles. Gloss values ranged between 31.9 and 50.6 GU at baseline and between 5.1 and 19.5 GU after 20,000 toothbrushing cycles. The lowest initial Ra value was detected in Venus Diamond and the highest initial gloss value was detected in Tetric EvoCeram. Conclusions: Simulated toothbrushing abrasion led to an increase in surface roughness and a decrease in gloss for all tested materials. Venus Diamond had the smoothest surface and Tetric EvoCeram had the glossiest surface after polishing and following 20,000 cycles of toothbrushing abrasion. Admira Fusion demonstrated the roughest surface and had the lowest gloss values before and after toothbrushing abrasion.

Mechanism of pro-apoptotic action of prosthetic restorations on oral mucosa cells

PURPOSE

The aim of this study was to check the pro-apoptotic mechanism of prosthetic reconstruction on epithelial cells of the oral mucosa.

PATIENTS AND METHODS

The research was carried out on the saliva of healthy patients using prostheses. The sample swabs were stained using the May-Grünwald-Giemsa method and processed by immunohistochemistry for nuclear factor kappa B (NF-κB; p65) and caspase-3. Western blots were used to detect caspase-3, NF-κB, p53 and COX-2 expression.

RESULTS

We found an increased expression of caspase-3, NF-κB and p53 in the oral epithelial cells of patients using prosthetic restorations compared to the subjects from the control group. No differences in COX-2 expression were found between the groups. The strongest immunoreactivity and expression of caspase-3, NF-κB and p53 were observed in patients using full prosthesis for less than two years.

CONCLUSIONS

The results of the conducted research indicate that prosthetic restorations may affect the process of apoptosis of oral mucosa epithelial cells. Lack of difference in expression of COX-2 in the saliva of the studied patients suggests that apoptosis is not caused by inflammatory factors.

Novel Dental Poly (Methyl Methacrylate) Containing Phytoncide for Antifungal Effect and Inhibition of Oral Multispecies Biofilm

Despite the many advantages of poly (methyl methacrylate) (PMMA) as a dental polymer, its antifungal and antibacterial effects remain limited. Here, phytoncide was incorporated into PMMA to inhibit fungal and biofilm accumulation without impairing the basic and biological properties of PMMA. A variable amount of phytoncide (0 wt % to 5 wt %) was incorporated into PMMA, and the basic material properties of microhardness, flexural strength and gloss were evaluated. In addition, cell viability was confirmed by MTT assay. This MTT assay measures cell viability via metabolic activity, and the color intensity of the formazan correlates viable cells. The fungal adhesion and viability on the PMMA surfaces were evaluated using Candida albicans (a pathogenic yeast). Finally, the thickness of saliva-derived biofilm was estimated. The flexural strength of PMMA decreased with increasing phytoncide contents, whereas there were no significant differences in the microhardness and gloss (p > 0.05) and the cell viability (p > 0.05) between the control and the phytoncide-incorporated PMMA samples. The amounts of adherent Candida albicans colony-forming unit (CFU) counts, and saliva-derived biofilm thickness were significantly lower in the phytoncide-incorporated PMMA compared to the control (p < 0.05). Hence, it was concluded that the incorporation of appropriate amounts of phytoncide in PMMA demonstrated antifungal effects while maintaining the properties, which could be a possible use in dentistry application such as denture base resin.