Prosthetic Rehabilitation of Cranial Defects: An Overview
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:2] [Pages No:33 - 34]
DOI: 10.5005/jp-journals-10019-1236 | Open Access | How to cite |
Functioning Implant: The Term that Needs to be Defined
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:1] [Pages No:35 - 35]
DOI: 10.5005/jp-journals-10019-1237 | Open Access | How to cite |
Importance of Systematic Reviews in Implant Dentistry
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:2] [Pages No:36 - 37]
DOI: 10.5005/jp-journals-10019-1234 | Open Access | How to cite |
Impact of Overdried Preparation and Thermocycling on the Fracture of CAD–CAM Hybrid Ceramic Occlusal Veneer Restorations
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:5] [Pages No:38 - 42]
Keywords: Fracture, Laboratory research, Occlusal veneers, Self-adhesive resin cement, Strength, Thermocycling
DOI: 10.5005/jp-journals-10019-1231 | Open Access | How to cite |
Aim: To study the impact of overdried preparations prior to cementation with a self-adhesive resin cement and thermocycling on the fracture of hybrid ceramic occlusal veneer restorations. Materials and methods: Sixty extracted maxillary molars were mounted and sectioned to remove the coronal structure 4 mm above the cementoenamel junction, leaving a flat area of exposed dentin and peripheral enamel. Ultrathin occlusal veneers with 0.3 mm central fossa thickness were milled from CAD–CAM hybrid ceramic (Vita Enamic). Teeth were randomly divided into three groups. After a selective enamel etching with phosphoric acid, groups I and II were blot-dried using cotton pellets; group III was desiccated with pressurized air for 15 seconds prior to cementation with a self-adhesive resin cement (Rely-X Unicem). Groups II and III were thermocycled between 5/55°C for 5000 cycles. The restored teeth were loaded axially until fracture. Fracture patterns were classified as fracture in the veneers only or fracture involving the tooth structure. Results: The fracture strengths (mean ± standard deviation) were 1672 ± 585, 1789 ± 722, and 1586 ± 711 N for groups I (control), II (thermocycled), and III (overdried and thermocycled), respectively. No statistically significant differences were indicated (one-way ANOVA, p = 0.6426). Fracture patterns were significantly different (the Kruskal–Wallis rank sum test for multiple independent samples, p = 0.01315, followed by the Dunn post hoc test), where group III had more fractures in the veneer only than groups I and II. Conclusion: Thermocycling of samples and overdrying of preparations did not show a significant difference in failure strength. However, fracture patterns indicated more veneer-only fractures under desiccated conditions, suggesting compromised restoration bonding.
Stress Distribution Analysis at the Bone–Implant Interface Using Four Different Superstructure Materials in an Implant-retained Mandibular Overdenture: A Photoelastic Study
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:4] [Pages No:43 - 46]
Keywords: Cast metal, Glass fiber, Implant-retained overdenture, Laboratory research, PEEK, Photoelasticity, Polymethylmethacrylate, Superstructure
DOI: 10.5005/jp-journals-10019-1230 | Open Access | How to cite |
Aim: To analyze and depict the stress distribution at the bone–implant interface using four different superstructure materials for an implant-retained overdenture, through a photoelastic study. Materials and methods: The present study included construction of photoelastic models of an edentulous mandible with two implants in the parasymphseal region. On these models, the dentures were fabricated using conventional heat cure acrylic, heat cure acrylic reinforced with NiCr, heat cure acrylic reinforced with a fiber force mesh, and heat cure acrylic reinforced with PEEK. These models were then subjected to photoelastic stress analysis. Results: The results showed a higher number of fringes in the denture fabricated with heat cure acrylic reinforced with NiCr. The fringes were better distributed in the photoelastic model with denture fabricated using heat cure acrylic reinforced with PEEK. Conclusion: The stress distribution in the bone–implant interface is markedly improved when an acrylic resin prosthesis is reinforced with PEEK as a superstructure material.
Effect of Incorporation of an Antimicrobial Monomer 2-tert-Butylaminoethyl Methacrylate on the Flexural Strength and Impact Strength of a Heat-polymerized Acrylic Resin: An In Vitro Study
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:4] [Pages No:47 - 50]
Keywords: Custom-made metal molds, Denture base, Drawback, Microorganisms, Success
DOI: 10.5005/jp-journals-10019-1233 | Open Access | How to cite |
Aim: To evaluate the effect of incorporation of 2-tert-butylaminoethyl methacrylate (TBAEMA) on the flexural strength and impact strength of a heat-polymerized acrylic resin. Materials and methods: A total number of 240 specimens were fabricated, 120 each for flexural strength and impact strength. Further, four groups were divided according to the concentration of TBAEMA incorporated to the acrylic resin (DPI): 0%, 0.5%, 1% and 2%. Flexural strength and impact strength of the specimens was tested and results were analyzed by ANOVA and Tukey's test (p value ≤ 0.05). Results: Significant difference was found for both flexural strength and impact strength (p value ≤ 0.05). Conclusion: Within the limitations of this study, it was concluded that the flexural strength and impact strength gets altered, depending on the concentration of TBAEMA.
Comparison of Microleakage of Class V Restoration with Self-etch and Selective-etch Adhesive Systems: An In Vitro Study
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:5] [Pages No:51 - 55]
Keywords: Adhesive, Composite resin, Microleakage, Self-etch adhesives
DOI: 10.5005/jp-journals-10019-1229 | Open Access | How to cite |
Purpose: This in vitro study is to evaluate the microleakage of the universal and self-etch adhesives in selective-etch and self-etch techniques by evaluating dye penetration. Materials and methods: In this study, a total of 48 restoration and caries-free maxillar or mandibular anterior teeth were used. Standardized class V cavities (1.5 mm deep, not beveled, rounded corners) were prepared on buccal surfaces of all teeth, which were gingival edges above from the enamel-cement junction. A total of 48 teeth were randomly separated into four groups. The first group was restored with Clearfil S3 Bond Plus (Kuraray, Tokyo, Japan) in the self-etch technique. The second group was restored with single bond universal (SBU) adhesive L-pop (3M ESPE, St. Paul, USA) in the self-etch technique. The third group was restored with Clearfil S3 Bond Plus (Kuraray, Tokyo, Japan) in the selective-etch technique. The fourth group was restored with single bond universal adhesive L-pop (3M ESPE, St. Paul, USA) in the selective-etch technique. Final finishing and polishing of the restorations were performed by using discs (ZenitFlex, Munich, Germany). They were thermocycled for 5,000 thermal cycles between water baths at 5°C and 55°C. All surfaces were isolated with two layers of nail polish, except up to 1 mm from the restoration margin for correct evaluation of the microleakage. The apices of all teeth were covered with a composite resin (Clearfil Majesty Esthetic, Kuraray, Tokyo, Japan). The teeth were stored in an oven with 2% methylene blue solution for 24 hours. The samples were embedded in acrylic resin in plastic molds. Results: Microleakage scores (count and percentages) for all four groups are shown in Table 2. The Kruskal–Wallis test was applied to determine the differences between microleakage scores in the four study groups at a 0.05 level of significance. No statistically significant difference was found (p > 0.05). Conclusion: The two adhesive systems showed clinically acceptable microleakage values in two different application techniques.
Effect of Sandblasting on the Bond Strength between CAD–CAM Milled Metal Post and Direct Metal Laser-sintered Metal Post: A Comparative In Vitro Study
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:7] [Pages No:56 - 62]
Keywords: Bond strength, Computer-aided design and computer-aided machining, Direct metal laser-sintering
DOI: 10.5005/jp-journals-10019-1232 | Open Access | How to cite |
Aim: To assess and compare the bond strength of Co–Cr metal posts fabricated with 2 different techniques: computer-aided design and computer-aided machining (CAD–CAM) and direct metal laser-sintering (DMLS). Materials and methods: Sixty extracted noncarious, human maxillary central incisor teeth with a similar morphology were decoronated 2 mm coronal to the cementoenamel junction (CEJ) and the roots were endodontically treated. Post space was prepared leaving 5 mm of gutta percha within the root canal. Co–Cr metal posts were fabricated according to CAD–CAM and direct metal laser-sintering (DMLS) techniques and were randomly divided into four study groups: group I, CAD–CAM milled metal post without sandblasting; group II, DMLS metal posts without sandblasting; group III, CAD–CAM milled metal post with sandblasting; and group IV, DMLS metal posts with sandblasting. After sandblasting posts were cemented with glass ionomer cement, pull-out bond strength test was performed using a universal testing machine. Using Kruskal–Wallis with post hoc (Mann–Whitney) tests statistical analysis of data was performed. Result: The highest pull-out bond strength was reported in group-IV (mean value = 6.65 ± 3.10 MPa). And the lowest was recorded for group-I (mean value = 4.38 ± 2.69 MPa). No significant difference in pull-out bond strength was found among the different groups (p > 0.05) due to smaller sample size. Conclusion: Within the limitations of this study, results suggest that surface treatment with sandblasting with 50 μm aluminum oxide particles was found to be an effective method for improving the bond between the DMLS and CAD–CAM milled metal posts.
Application of CAD–CAM Milled Zirconia Attachment in Kennedy's Class III Partially Dentate Situation: A Series of Clinical Reports
[Year:2019] [Month:April-June] [Volume:9] [Number:2] [Pages:4] [Pages No:63 - 66]
Keywords: Attachments, CAD–CAM, Zirconia
DOI: 10.5005/jp-journals-10019-1235 | Open Access | How to cite |
Background: Rapid developments of ceramic technology have increased applications of zirconia in dentistry. It is widely used for full, partial coverage crowns, inlays, onlays, post, and core. Though recommended, zirconia has not been widely used as precision attachment to support a cast metal partial denture prosthesis. Aim: The purpose of this clinical report was to use CAD–CAM milled zirconia as an extra coronal attachment to retain a cast metal partial denture prosthesis. Case description: Two partially dentate patient requiring removable prosthesis and anterior fixed dental prosthesis were considered for the study. One piece CAD–CAM milled anterior zirconia bridge with extra-coronal attachment at distal ends was fabricated and metal removable prosthesis was delivered. Patients were followed up periodically for two years. Two year periodic follow up showed application of CAD–CAM milled zirconia attachments to retain metal removable prosthesis was clinically acceptable. Patient reported satisfaction with function and esthetics. Conclusion: Use of CAD–CAM milled zirconia anterior bridge with extracoronal attachment to retain metal removable prosthesis can enhance esthetics with increased patient acceptance.