scholarly journals The role of surface treatments on the bond between acrylic denture base and teeth

2009 ◽  
Vol 20 (2) ◽  
pp. 156-161 ◽  
Author(s):  
Lauro Egídio Bragaglia ◽  
Luiz Henrique Maykot Prates ◽  
Maria Cristina Marino Calvo

The aim of this study was to compare the bond strength between acrylic denture base and teeth subjected to 6 surface treatments. Ninety-six specimens were made with poly(methylmethacrylate) teeth bonded to a microwave-polymerized acrylic denture base material. The specimens were distributed into 6 groups (n=16) according to surface treatments: CT - no treatment (control); MN - methylmethacrylate monomer etching; AO - 50-µm-particle aluminum oxide air abrasion; BR - glaze removal with a round bur; ST - surface grinding with an aluminum oxide abrasive stone; group CV - cavity preparation (diatorics). The control and surface-treated groups were subjected to a compressive load at 45º angle to the long axis of the teeth. Data were analyzed by one-way ANOVA, followed by Scheffé's test (p<0.05). Bond strength means and (SD) in kgf for groups were: CT: 18.19 (7.14), MN: 18.34 (5.28), AO: 23.82 (5.40), BR: 23.30 (4.79), ST: 25.39 (7.80) and CV: 17.48 (7.17). There was statistically significant difference (p=0.037997) only between ST and CV. In conclusion, ridge lap surface grinding with an aluminum oxide abrasive stone provided the highest bond strength, though it differed significantly only when compared to diatorics. The other surface treatments provided similar bond between the acrylic denture base and teeth.

2006 ◽  
Vol 17 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Stenyo Wanderley Tavares ◽  
Simonides Consani ◽  
Darcy Flávio Nouer ◽  
Maria Beatriz Borges de Araújo Magnani ◽  
Paulo Roberto Aranha Nouer ◽  
...  

The purpose of this study was to evaluate in vitro the shear bond strength of recycled orthodontic brackets. S2C-03Z brackets (Dental Morelli, Brazil) were bonded to the buccal surfaces of 50 extracted human premolars using Concise Orthodontic chemically cured composite resin (3M, USA). The teeth were randomly assigned to 5 groups (n=10), as follows. In group I (control), the bonded brackets remained attached until shear testing (i.e., no debonding/rebonding). In groups II, III and IV, the bonded brackets were detached and rebonded after recycling by 90-mum particle aluminum oxide blasting, silicon carbide stone grinding or an industrial process at a specialized contractor company (Abzil-Lancer, Brazil), respectively. In group V, the bonded brackets were removed and new brackets were bonded to the enamel surface. Shear bond strength was tested in an Instron machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant difference (p>0.05) between the control brackets (0.52 kgf/mm²), brackets recycled by aluminum oxide blasting (0.34 kgf/mm²) and new brackets attached to previously bonded teeth (0.43 kgf/mm²). Brackets recycled by the specialized company (0.28 kgf/mm²) and those recycled by silicon carbide stone grinding (0.14 kgf/mm²) showed the lowest shear strength means and differed statistically from control brackets (0.52 kgf/mm²) (p<0.05). In conclusion, the outcomes of this study showed that bracket recycling using 90-µm aluminum oxide particle air-abrasion was efficient and technically simple, and might provide cost reduction for orthodontists and patients alike.


2020 ◽  
Vol 10 (2) ◽  
pp. 32-37
Author(s):  
Shilan H. Fatah ◽  
Radhwan H. Hasan

Today, soft liners are being widely used in dental practices by their application to the inner surfaces of the denture with hopes to evenly distribute any potential uneven forces, and to provide a cushion effect to the oral mucosa of the patient mouth. The aim of this study is to investigate the influence of (a) polymethylmethacrylate (PMMA) denture base material curing technique, (b) Molloplast B soft liner curing technique, and (c) PMMA surface treatment, on the “shear bond strength” (SBS) between the Molloplast B liner and PMMA. A total of 80 samples were used in this study to evaluate the SBS performance of microwave (Nature-Cryl, Acron Gc, Japan) and conventional water bath (Ivoclar triplex, Liechtenstein) curing techniques of PMMA, and to evaluate the curing technique of soft liner material Molloplast B (DETAX,GERMANY). Surface treatment of PMMA was performed for half of the samples using neodymium:yttrium aluminum-garnet Nd:YAG laser, and the other half of the samples were surface-treated using AL2O3 sandblasting method. The results showed that the highest mean value in conventional water bath-cured soft liner was 26.69 MPa, whereas the lowest mean value for microwave-cured soft liner was 15.22 MPa. No significant difference was observed between the SBS performance regarding the PMMA surface treatment and curing techniques. Conventional water bath curing technique for soft liner treatment improved the SBS performance. Regarding the PMMA curing technique, the conventional water bath achieved higher SBS, yet the difference was not statistically significant. Finally, surface treatment using laser improved the SBS compared to sandblasted method, but the improvement here was also statistically insignificant.


2009 ◽  
Vol 10 (5) ◽  
pp. 17-22 ◽  
Author(s):  
Ramin Mosharraf ◽  
Matin Abed-Haghighi

Abstract Aim Debonding of denture teeth from the denture base can be frustrating for both the clinician as well as his or her patients. The wear resistance of composite denture teeth has been well investigated since their introduction, but there have been few studies about the bonding of these teeth to acrylic denture base resins. The aim of this study was to compare the bond strengths of two brands of acrylic and one brand of multilithic denture teeth to acrylic denture base material. Methods and Materials In this experimental-laboratory study, three types of denture teeth—Yaghoot, Super Brilian, and Major—were used. After grinding the glossy ridge lap surfaces, the teeth were mounted on two sides of triangularshaped wax models. Then the wax elimination and resin processing laboratory procedures were carried out as is done with the fabrication of a complete denture. Each of the specimens was tested using a universal testing machine with a cross head speed of 5mm/min at an angle of 130 degrees to the long axis of the teeth. The data were analyzed using one-way ANOVA and Chisquare tests. Results The mean bond strength in the Yaghoot group was 717.43±293.59 N while in the Super Brilian group it was 578.40±395.38 and in the Major group, 547.95±296.75N. However, there was no significant difference between the three groups (p=0.194). Conclusion Although the mean bond strength in the multilithic group was higher than in the other groups, no significant difference was found between the three groups. There was no significant difference between the three groups with regard to the prevalence and type of fracture site. Clinical Significance The bonding strength of multilithic denture teeth to denture base resins was found to be comparable to, and even slightly higher than, acrylic conventional denture teeth, making them a promising choice for clinicians in the fabrication of removable dentures. Citation Mosharraf R, Abed-Haghighi M. A Comparison of Acrylic and Multilithic Teeth Bond Strengths to Acrylic Denture Base Material. J Contemp Dent Pract [Internet]. 2009 Sept; 10(5). Available from: http://www.thejcdp.com/journal/ view/a-comparison-of-acrylic-andmultilithic-teethbond- strengths-to-acrylic-den.


2016 ◽  
Vol 17 (2) ◽  
pp. 154-159 ◽  
Author(s):  
Farzaneh Ahrari ◽  
Mohammadreza Nakhaei ◽  
Hossein Dashti ◽  
Samaneh Vasigh ◽  
Shazia Mushtaq ◽  
...  

ABSTRACT Aim The aim of this study is to evaluate the effects of three different surface treatments and thermocycling on the tensile strength of a silicone lining material to denture resin. Materials and methods A total of 96 cube-shaped specimens were fabricated using heat-cured polymethyl methacrylate (PMMA) denture base resin. Three millimeters of the material was cut from the midsection. The specimens were divided into four groups. The bonding surfaces of the specimens in each group received one of the following surface treatments: no surface treatment (control group), airborne particle abrasion with 110 μm alumina particles (air abrasion group), Er:yttrium aluminum garnet laser irradiation (laser group), and air abrasion + laser. After the lining materials were processed between the two PMMA blocks, each group was divided into two subgroups (n = 12), either stored in distilled water at 37°C for 24 hours or thermocycled between 5 and 55°C for 5,000 cycles. The specimens were tested in tensile and shear strength in a universal testing machine. Data were analyzed with two-way analysis of variance and Tamhane's post hoc tests (α = 0.05). The mode of failure was determined, and one specimen in each group was examined by scanning electron microscopy. Results Surface-treated groups demonstrated significantly higher tensile strengths compared to the control group (p < 0.001). Nonetheless, no significant differences were found between surface-treated groups (p > 0.05). The tensile strength was significantly different between thermocycled and waterstored specimens (p = 0.021). Conclusion Altering the surface of the acrylic denture base resin with air abrasion, laser, and air abrasion + laser increased the tensile strength. Thermocycling resulted in decrease in bond strength of silicone-based liner to surface-treated acrylic resin. Clinical significance Pretreatment of denture base resins before applying the soft liner materials improves the bond strength. However, thermocycling results in decrease in bond strength of soft denture liner to surface-treated acrylic resin. How to cite this article Nakhaei M, Dashti H, Ahrari F, Vasigh S, Mushtaq S, Shetty RM. Effect of Different Surface Treatments and Thermocycling on Bond Strength of a Silicone-based Denture Liner to a Denture Base Resin. J Contemp Dent Pract 2016;17(2):154-159.


2019 ◽  
Vol 13 (3) ◽  
pp. 227-233
Author(s):  
Tahereh Ghaffari ◽  
Elnaz Moslehifard ◽  
Mehrnaz Motiei

Background. Due to the fragile nature of all-ceramic restorations, it is necessary to provide an appropriate (core) infrastructure to support the veneering porcelain. The veneer detachment and chipping are disadvantages of these restorations. Several techniques have been proposed to minimize these problems. This study evaluated the effect of thermal and mechanical cycles on the shear bond strength of zirconia core to porcelain veneer under different surface treatments. Methods. Sixty disk-like zirconium samples were randomly divided into three groups. The first group was polished and veneered with porcelain, without additional surface treatments. The two other groups were subjected to different surface treatments (modified aluminum oxide by silica and activator‒aluminum oxide and primer) and veneering with porcelain. Half of the samples in each group were subjected to 6000 thermal cycles and 20,000 masticatory cycles of 50 N to imitate the intraoral conditions; the other half were placed in distilled water at 37°C until the shear strength test. Each sample was then buried using PMMA in a mounting jig so that the gap between the core and the veneer could be placed upward. Then, they were exposed to shear stress using a universal testing machine at a rate of 1 mm/min until fracture. The maximum force leading to the fracture was recorded. Results. Comparison of the groups showed that the highest shear bond strength was related to the samples treated with aluminum oxide and primer, without applying thermal and masticatory cycles, which indicated no significant difference from the group treated with aluminum oxide and primer, with thermal and masticatory cycles. The lowest shear bond strengths were related to the polished samples without surface treatment by applying thermal and masticatory cycles (P=0.001), which indicated no significant difference from the untreated group without thermal and masticatory cycles. Conclusion. Based on the results, treatment with aluminum oxide and primer increased the shear bond strength of zirconia core to porcelain veneer. Thermocycling and masticatory cycles failed to reduce the shear bond strength in all the three groups significantly.


Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1527
Author(s):  
Mohammed E. Sayed ◽  
Honey Lunkad ◽  
Ibrahim Fageeh ◽  
Mahdi Jaafari ◽  
Ali Tawhari ◽  
...  

Debonding and detachment of artificial teeth from the denture base is frequently encountered in prosthodontic practice. This study aims to assess the effect of modifications in the ridge-lap surface of denture teeth with various combinations of mechanical and chemical surface treatments with hydrofluoric acid on bond strength with the acrylic denture base resin and to identify the failure modes (adhesive, cohesive, or mixed). Seventy acrylic resin teeth samples were randomly divided into seven groups (n = 10): a control group (unmodified) and six treatment groups, in which various combinations of mechanical and chemical surface treatments were performed. Then, these teeth were attached to a heat-cured denture base resin block at 45° angulation. The acrylized test samples were thermocycled, and the compressive bond strength was evaluated using a universal mechanical testing machine. The results suggest that roughening with diamond burs yields the highest bond strength, whereas etching/grooving and air abrasion result in the lowest bond strength. Acid etching complemented air abrasion to improve bond strength, while negative effects were noted with acid etching in other groups. Furthermore, roughening at the neck portion of the acrylic teeth can be used by the manufacturing companies as a standard to provide higher bond strength while maintaining the esthetics of the anterior teeth.


2019 ◽  
Vol 14 (1) ◽  
pp. 99
Author(s):  
Dr. Hikmat J. Al-Judy

Background: Soft lining materials play an important role in modern prosthodonticstreatment because of their capability to restore the inflamed and distorted mucosa.The purpose of the research was to estimate the influence of acrylic denture basereinforcement with silanted nano fillers (Al2O3 and Sio2) separately on tensile andshear bond strength of soft lining material and studying effect of thermo cyclingon bonding strength.Materials and methods: Total 120 specimens were prepared; it divided into 60Specimens for shear bond strength test and 6o specimens for tensile bond strengthtest. Specimens were sub grouped into 30 Specimens without thermo cycling and30 specimens with thermo cycling. Each sub group is consisted from: 10Specimens control, 10 specimens were reinforced with 2 wt% of Al2O3 nano fillersand 10 specimens were reinforced with 5 wt% of SiO2 nano fillers. Samples wereprocessed depending on test applied. Soft lining material was applied for eachtesting group. Samples were immersed in distal water for 24 hours at 37°C beforetesting. For thermo cycling test, specimen were thermo cycled in thermo cyclingdevice. Bonding strength test was done using INSTRON universal testingmachine.Results: reinforcement of acrylic denture base with nano-fillers was significantlyincrease both tensile and shear bonding of lining material and thermo cyclingdecreases both bonding strength.Conclusion: reinforcement of acrylic denture base with nano fillers could improvebonding strength of lining material, while thermo cycling had a deleterious effecton bonding strength.


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