The Effect of Sandblasting on Bond Strength of Soft Liners to Denture Base Resins: A Systematic Review and Meta-Analysis of In Vitro Studies

Objectives. This study aimed to evaluate the effect of sandblasting on the bond strength of denture base resin to soft liners. Materials and Methods. This report follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. PubMed, Embase, Cochrane, Scopus, and OpenGrey databases were searched for in vitro studies that compared sandblasting with no treatment in terms of the tensile, shear, and peel bond strength of resilient lining materials (acrylic-based or silicone-based) to polymethyl methacrylate denture base resin. Based on the outcome, the analysis was carried out in three groups of tensile, shear, and peel bond strength. Subgroup analysis was done for the effect of size of particles on sandblasting, blasting pressure, and type of soft liner whenever possible. Heterogeneity was evaluated among the studies, and meta-analysis was performed with random effect models ( p < .05 ). Results. After screening, 16 articles met the inclusion criteria for meta-analyses. No treatment showed significantly higher tensile ( p < 0.001 ) or peel ( p = 0.04 ) bond strength, although shear bond strength of sandblasted resin was significantly better ( p = 0.008 ). Results of subgroup analyses of particle size favored the control group in 50 µ Al2O3 particle size ( p < 0.001 ). In analyses of blasting pressure, the control group had significantly better tensile bond strength than specimens with blasting pressure ≤1 bar ( p < 0.001 ) while specimens with blasting pressure beyond 1 bar showed significantly more tensile strength than control group ( p = 0.03 ). In silicon-based liners, groups without any surface treatment had significantly higher tensile bond strength ( p < 0.001 ). Conclusion. According to the in vitro studies, sandblasting would not lead to significant increase in bond strength of soft liner to the denture base resin.

Comparative Evaluation of the Amount of Sorption and Solubility Seen in Soft Liner with Herbal and Commercially Available Denture Cleanser - An In vitro Study

Aims: the aim of the current study is to assess the quantity of sorption and solubility seen in the soft denture liner with herbal (neem) and commercially (clinsodent) available denture cleanser. Materials and Methods: The cross sectional study was carried out in the Department of Prosthodontics at Sharad Pawar Dental College And Hospital between February 2021 and July 2021. 52 samples of heat cured acrylic resin of circular shape were prepared using a stainless steel mould. The resilient liner was applied to all the samples using a denture adhesive. All samples will then be desiccated for 24 hours to get a stable or conditioned weight W1. The samples will then be divided into 2 groups namely: Group A (clinsodent group) and the Group B (herbal denture cleanser group). All the samples were immersed daily in cleanser for 8 hour and then transferred to artificial saliva for rest 16 hours of the day. Solutions of artificial saliva and denture cleanser was changed daily for the entire period of study that is 7 days. Later, all the test samples were removed from saliva, wiped dry, weighed for saturated weight W2. - After desiccating again for 24 hours the samples were again assessed for renovated weight that is W3. Results: With respect to sorption and solubility it was found that the clinsodent group exhibited greater percentage of sorption when compared to the neem denture cleanser group after a period of 7 days, p-values of 0.0001,S. Conclusion: It can be established that the solubility and sorption values of clinsodent group were higher when compared to the herbal denture cleanser group. Overall, neem in the form of denture cleanser performed better than clinsodent.

Evaluation of Helium Plasma Surface Modification on Tensile Bond Strength of Denture Base Materials: A Scanning Electron Microscope Study

The purpose of this study was to compare the effect of helium plasma treatment on tensile bond strength between polymethylmethacrylate and soft liner material. For the tensile test, acrylic samples (30 x 10 x 10 mm³; n=100) were prepared. Acrylic samples were divided into five surface groups (n = 10/group) and treated by different concentrations of helium plasma: G I: Control group (untreated), G II: 100% Helium plasma-treated group, G III: 90% Helium plasma-treated group, G IV: 85% Helium plasma-treated group, G V: 80% Helium plasma-treated group. After plasma treatment, the soft liner was processed between two acrylic resin blocks according to the manufacturer's instructions and polymerized. The surface properties were evaluated by scanning electron microscopy and atomic force microscopy. All samples were submitted to a tensile test using a universal testing machine. After failure, the surface properties were evaluated by stereomicroscope. One-way analysis of variance was used to compare the groups. p <0.05 value was considered statistically significant. While the highest mean tensile bond strength value was obtained with the G III (1.56 ± 0.13 MPa), the lowest value was observed with the G I (0.95 ± 0.2 MPa). In addition, it was observed that the surface roughness increased the most in G III.

Methods for Candida albicans biofilm formation on temporary soft liner/ Métodos para a formação de biofilme de Candida albicans em reembasador macio temporário

This study evaluated methods for the contamination of a soft liner material (Softone™) with Candida albicans biofilm. Specimens were either submitted or not to pretreatment in artificial saliva in an orbital incubator, and then held suspended in different positions (horizontal or vertical) and different storage conditions (bacteriological incubator or orbital incubator) during biofilm formation. Eight conditions were tested. All specimens were immersed in C. albicans inoculum and stored in an orbital incubator at 75 rpm or in a bacteriological incubator, both at 37ºC for 90 min. Then, they were washed in PBS, and maintained in RPMI-1640 medium under the same conditions for 48 h. The degree of contamination was determined by the XTT assay. Data were submitted to ANOVA 1-factor/Tukey HSD test (α=0.05). Specimens held horizontally in an orbital incubator showed the highest cell viability, while the ones kept vertically in a bacteriological incubator had the lowest viability (p0.0001). The best condition for C. albicans biofilm formation was obtained when specimens were not submitted to pretreatment in saliva and were held horizontally in an orbital incubator.

Estimation of the autoclave and different surface treatments on microleakage between soft liner and heat-cured acrylic

Objective: The present study was oriented to estimate the effect of different surface treatments on the microleakage between the soft liner and acrylic with and without the use of autoclave as disinfection method. Material and Methods: Sixty samples were split into two groups: the autoclaved groups and non-autoclaved groups. Each one subdivided into three groups: first one without any treatments as a control group; in the second group surface of the samples were treated with CO2 laser (10.6 nm wavelength for 15 seconds), and in the third group the surface was treated with sandblasting. All the samples exposed to thermocycling, then the microleakage test was evaluated by gauging dye penetration depth between the soft liner and acrylic disc using a digital microscope. Data analyzed statistically by One-way ANOVA and Tukey's post-hoc tests. In addition, t-test was used for comparison between two groups . Results: The maximum mean values for the microleakage were observed in the untreated group (control) followed by the group treated by CO2 laser and the lowest mean value of microleakage was related to the third group for both non-autoclaved and autoclaved groups with significant differences among them. In addition, depending on the use of autoclave, there was non-significant in all studied groups. Conclusions: There was a decrease in the microleakage when the surface treated with CO2 laser and sandblast. The use of autoclave did not badly change the microleakage between the soft liner and denture base. Keywords Microleakage; Soft liner; Autoclave; CO2 laser; Sandblast.

Effect of plasma treatment on the bond of soft denture liner to conventional and high impact acrylic denture materials

Background: The main drawback of soft lining materials was that they debonded from the denture base after a certain period of usage. Therefore, the purpose of this research was to determine the impact of oxygen and argon plasma treatment on the shear bonding strength of soft liners to two different kinds of denture base materials: conventional acrylic resin and high impact acrylic resin. Materials and Methods: Heat cure conventional and high impact acrylic blocks (40 for each group) were prepared. A soft liner connected the final test specimen of two blocks of each acrylic material. Shear bond strength (SBS) was assessed using universal testing machine. Additional blocks were also prepared for analyzing Vickers microhardness, contact angle, FTIR and AFM. The results were statistically analyzed using paired-sample T-test and independent-samples T-test (α=0.05). Results: The results showed a highly significant increase in SBS following plasma treatment with the highest mean value observed in plasma treated high impact acrylic specimen. Along with a significant rise in wettability, while microhardness was preserved. Conclusion: In conclusion, oxygen and argon plasma treatment was significantly effective in enhancing the SBS between soft liner and acrylic materials.

Management of Flabby Ridges using Liquid Supported Denture

The concept of conditioning edentulous ridge mucosa has gained momentum over the last several years. Frequent relining of the complete denture may be required because of soft tissue changes arising from underlining bone resorption. Patients with the maxillary flabby ridge had difficulty in tolerating hard denture, inadequate retention, and stability of a complete denture are often encountered, so the denture can be made more comfortable using soft liner. Hardening of the soft liner with time, harboring of bacteria, and debonding from denture base is a major drawback of soft lining materials. Introduction of liquid-supported dentures, to be an alternative to conventional complete denture prosthesis in cases suffered from inflamed tissues and severely resorbed edentulous ridges. A liquid supported denture provides an alternate treatment option due to its soft and flexible intaglio surface allows better distribution of masticatory load stress since in such cases. Liquid supported acrylic complete denture can be useful as a permanent solution in edentulous patients with the atrophied ridge. Liquid supported denture could be a useful alternative for soft relining materials.

PREPARATION FOR PALATOPLASTY SURGERY WITH AN ACRYLIC FEEDING OBTURATOR: A CASE REPORT

ABSTRACTBackground: Clefts on the lips and palate are common cases to be found frequently in the field of dentistry. This gap connects the oral cavity and the nasal cavity so that it interferes with the nutritional intake in patients. The age and size of the oral cavity in patients become particular challenges for prosthetic rehabilitation. Another challenge lies at the impression procedure, because it is an essential part in the making of obturator. Objective: To provide information on the management of patient with cleft palate using feeding obturator from acrylic material. Case: A 13-months-old male patient arrived at Prof. Soedomo Gadjah Mada University Dental Hospital with his parents and was seeking for prosthetic therapy to cover the cleft on his palate because it had been muddling with food and beverage intake. Patient had undergone cheiloplasty surgery and further arranged for palatoplasty procedure. Intraoral examination exhibited a cleft extended from hard palate, soft palate, and uvula. Case management: Upper jaw impression was performed for individual tray fabrication, followed by impression procedure in an upright straight position until the patient bawled. The impression result was casted to construct an obturator using acrylic heat cure material. Fitting surface was covered with soft liner. Treatment result showed that the obturator was retentive, stable and able to assist the nutritional intake in patient. Conclusion: Acrylic feeding obturator can recover the condition in patient with cleft palate and improve nutritional intake as well as body weight to prepare patient for palatoplasty surgery.Keywords: Cleft Palate, Feeding Plate, Obturator