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Journal of Indian Prosthodontic Society Jul 2024This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to... (Comparative Study)
Comparative Study
Comparative evaluation of bond strength and color stability of polyetheretherketone and zirconia layered with indirect composite before and after thermocycling: An in vitro study.
AIM
This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to assess the shear bond strength (SBS) and color stability of zirconia and PEEK before and after aging, addressing critical concerns in dental restorative applications.
SETTINGS AND DESIGN
The current in vitro study used 96 samples, 48 of which were divided into two groups, zirconia and PEEK, before and after thermocycling. A dual-axis chewing simulator was used for thermocycling. SBS was measured using a universal testing machine, and color stability was checked using a reflective spectrophotometer.
MATERIALS AND METHODS
Ninety-six samples were categorized into zirconia and PEEK groups, each with subgroups undergoing thermocycling. Samples were prepared using computer-aided design/computer-aided manufacturing milling and veneered with composite resin. Thermocycling involved 10,000 cycles, simulating stress levels equivalent to approximately 1 year of clinical use. SBS was assessed using standardized tests. Stereomicroscopic analysis was performed to evaluate the type of failure. Color stability of the core materials with indirect composite was done using a spectrophotometer before and after aging.
STATISTICAL ANALYSIS USED
Statistical analysis included paired t-tests and independent t-tests in SPSS software.
RESULTS
The results revealed that SBS values for composite on PEEK decreased from 13.86 ± 0.164 MPa before thermocycling to 13.46 ± 0.185 MPa after thermocycling, with a significant difference (P < 0.005). However, both pre- and postthermocycling values for PEEK were higher than zirconia. The t-test confirmed the lower bond strength of composite to zirconia, with a noteworthy improvement after aging. Stereomicroscopic images revealed adhesive failure for the zirconia group and mixed (adhesive and cohesive) failure for the PEEK group. ΔE values were 3.21 ± 0.127 and 2.93 ± 0.142 for zirconia and PEEK groups, respectively (P < 0.005).
CONCLUSION
Within the limitations of this study, it can be deduced that PEEK is a feasible substitute for zirconia when used in conjunction with indirect composite for the fabrication of dental prostheses.
Topics: Benzophenones; Zirconium; Ketones; Polyethylene Glycols; Polymers; Composite Resins; In Vitro Techniques; Dental Bonding; Color; Materials Testing; Shear Strength; Dental Materials; Dental Stress Analysis; Humans
PubMed: 38946508
DOI: 10.4103/jips.jips_36_24 -
Journal of Indian Prosthodontic Society Jul 2024Synthetic inorganic materials are commonly used as reinforcing agents in polyetheretherketone (PEEK) composite, whereas natural organic plant-based reinforcing agents... (Comparative Study)
Comparative Study
Comparative evaluation on surface nanohardness, surface microhardness, surface roughness, and wettability of plant-based organic nanoparticle reinforced polyetheretherketone as an implant material - An in vitro study.
AIM
Synthetic inorganic materials are commonly used as reinforcing agents in polyetheretherketone (PEEK) composite, whereas natural organic plant-based reinforcing agents are negligible. Surface hardness, roughness, and wettability are indicative factors of osseointegration behavior to be used as an implant material. This study evaluated micro surface hardness (MSH), nano surface hardness (NSH), surface roughness (SR), and contact angle (CA) of PEEK-Azadirachta indica reinforced at 10 wt%, 20 wt%, and 30 wt%.
SETTINGS AND DESIGN
This was an in vitro study.
MATERIALS AND METHODS
Neem (A. indica) leaf nanoparticles were prepared and reinforced with PEEK powder at 10%, 20%, and 30% weight ratios by injection molding. Sixty specimens underwent the microhardness and CA testing using a digital microhardness tester, and CA goniometer, respectively, and later nanoindentation test to analyze the nanohardness and SR.
STATISTICAL ANALYSIS USED
A one-way ANOVA test with a 95% confidence interval for MSH and NSH, SR, and CA was performed on the samples. A post hoc Bonferroni test was conducted (α = 0.05) to compare the groups.
RESULTS
There was a significant increase in nanohardness (P = 0.000) with zero difference in microhardness (P = 0.514). The addition of 10 wt%, 20 wt%, and 30 wt% nanoparticles increased the SR value of the pure PEEK from 273.19 nm to 284.10 (3.99%), 296.91 (8.68%), and 287.54 (5.24%), respectively. In the analysis of the CA, CA 20% shows the lowest angle (63.69) with the highest for control specimens (82.39). There is an increase in the PEEK composite SR with a decrease in CA.
CONCLUSIONS
The addition of plant-derived nanoparticles into the PEEK matrix has a significant impact on the hardness and hydrophobicity enhancing cell growth and osteoblastic differentiation during osseointegration of dental implants.
Topics: Benzophenones; Polyethylene Glycols; Polymers; Ketones; Nanoparticles; Surface Properties; Wettability; Hardness; In Vitro Techniques; Dental Implants; Materials Testing; Plant Leaves
PubMed: 38946507
DOI: 10.4103/jips.jips_511_23 -
Journal of Indian Prosthodontic Society Jul 2024The aim is to determine thermal conduction by heat-activated polymethylmethacrylate (PMMA) infiltrated with 1 weight% Titanium Dioxide (TiO2) and 1 weight% Zirconium...
Effect of titanium dioxide and zirconium dioxide nanoparticle incorporation on the thermal conductivity of heat-activated polymethylmethacrylate denture base resins: An in vitro experimental study.
AIM
The aim is to determine thermal conduction by heat-activated polymethylmethacrylate (PMMA) infiltrated with 1 weight% Titanium Dioxide (TiO2) and 1 weight% Zirconium Dioxide (ZrO2) nanoparticles and to compare with that of conventional PMMA.
STUDY SETTING AND DESIGN
In vitro experimental study.
MATERIALS AND METHODS
Eighteen disc shaped specimens with a thickness of 5 mm and diameter of 50 mm, were fabricated and grouped according to the material used: Group B1 (resin infiltrated with 1 weight% TiO2), Group B2 (resin infiltrated with 1 weight% ZrO2), and Control Group B3 (heat-activated conventional PMMA resin). Disc-shaped specimens were analyzed for thermal conductivity using "modified guarded hot plate apparatus" in the thermal lab of the Indian Space Research Organisation.
STATISTICAL ANALYSIS USED
One-way ANOVA followed by Tukey's post hoc test was used to compare the arithmetic means of all three groups.
RESULTS
A statistically significant difference was noted among all three groups. Group B2 had the maximum thermal conductivity, followed by Group B1. Thermal conductivity was the least for Group B3. A post hoc comparison revealed that the difference was significant between Group B2 and Group B3.
CONCLUSION
Nano ZrO2 addition in PMMA increased its thermal conductivity. There is evidence that it improves its mechanical properties as well. Hence, Nano ZrO2 addition in PMMA is highly recommended. Nano TiO2 addition in PMMA did not provide any significant advantage in terms of thermal conductivity, but its addition in PMMA is justified because of its mechanical and antimicrobial properties.
Topics: Titanium; Zirconium; Polymethyl Methacrylate; Thermal Conductivity; Nanoparticles; Hot Temperature; Denture Bases; Materials Testing; In Vitro Techniques
PubMed: 38946506
DOI: 10.4103/jips.jips_575_23 -
Journal of Indian Prosthodontic Society Jul 2024The aim of this study was to compare the marginal fit of prefabricated occlusal veneers with computer-aided design/computer-aided manufacturing (CAD-CAM)-milled zirconia... (Comparative Study)
Comparative Study
A comparative evaluation of marginal fit and microleakage of computer-aided design/computer-aided manufacturing-milled zirconia and prefabricated posterior occlusal veneers: An in vitrostudy.
AIMS
The aim of this study was to compare the marginal fit of prefabricated occlusal veneers with computer-aided design/computer-aided manufacturing (CAD-CAM)-milled zirconia occlusal veneers in the posterior teeth.
SETTINGS AND DESIGN
Forty extracted human maxillary premolars were divided into two groups of 20 each. Group 1 was prepared to receive prefabricated occlusal veneers, and Group 2 was prepared to receive CAD-CAM-milled zirconia occlusal veneers.
MATERIALS AND METHODS
Prefabricated samples (Edelweiss) were selected for Group 1, whereas for Group 2, the tooth preparations were scanned, and occlusal veneers were fabricated using Exocad designing software and milling machine. After luting, both the groups were submerged in dye, sectioned, and evaluated for marginal fit and microleakage under a stereomicroscope using the microscope imaging software and its measurement tool.
STATISTICAL ANALYSIS USED
Data collected were subjected to statistical analysis using SPSS 27.0. Intragroup and intergroup comparison was done using the Mann-Whitney U test. The Chi-square test was applied to check the depth of penetration of dye based on percentages.
RESULTS
The marginal gap of zirconia occlusal veneers fabricated with CAD-CAM is higher compared to that of prefabricated occlusal veneers. Similarly, the depth of penetration of dye is higher in CAD-CAM-milled zirconia occlusal veneers than prefabricated occlusal veneers.
CONCLUSION
The marginal fit of prefabricated occlusal veneer is better than the marginal fit of zirconia occlusal veneers fabricated with CAD-CAM. Similarly, it can also be concluded that the microleakage of prefabricated occlusal veneer is less compared to the CAD-CAM-milled zirconia occlusal veneers.
Topics: Dental Veneers; Zirconium; Computer-Aided Design; Humans; Dental Marginal Adaptation; Dental Leakage; Dental Prosthesis Design; In Vitro Techniques; Bicuspid
PubMed: 38946505
DOI: 10.4103/jips.jips_346_23 -
Journal of Indian Prosthodontic Society Jul 2024The present systematic review compares the stability, crestal bone levels and efficacy of osseodensification (OD) drilling techniques for dental implant placement to... (Comparative Study)
Comparative Study
AIM
The present systematic review compares the stability, crestal bone levels and efficacy of osseodensification (OD) drilling techniques for dental implant placement to traditional drilling methods.
SETTINGS AND DESIGN
The Cochrane online library, PubMed, Scopus, and other well-known online resources are used in the research. Using a systematic review design, the current study examines published qualitative studies with an emphasis on analysis.
MATERIALS AND METHODS
Using precise keywords, a thorough search of pertinent databases was carried out in accordance with PRISMA standards. Studies testing dental implant stability, crestal bone levels and clinical results using both OD and traditional procedures were covered by the inclusion criteria.
STATISTICAL ANALYSIS USED
The risk of bias and quality of included studies was assessed using the Newcastle-Ottawa Scale for observational studies and the Cochrane Risk of Bias tool for randomized controlled trials.
RESULTS
A total of 170 patients and 334 implants from Egypt, India, and Brazil were included in eight papers that made up the systematic review. In several clinical situations, osseodensification outperformed standard drilling in terms of implant durability, bone development, and torque data. Statistical analysis presented the lowest risks, while blinded outcome assessment, allocation concealment, random sequence generation, incomplete outcome data and experimental technique revealed higher risks. Bias assessment found various risks across different components.
CONCLUSION
The thorough examination of eight papers demonstrates that osseodensification is a technique with great promise in the field of dental implants. It exhibits superior torque values, bone development, and stability when compared to traditional drilling. The overall results highlight the potential of osseodensification to improve clinical outcomes and advance the science of dental implantology, even in the face of variances in bias concerns.
Topics: Humans; Dental Implants; Dental Implantation, Endosseous; Osseointegration
PubMed: 38946504
DOI: 10.4103/jips.jips_480_23 -
Journal of Indian Prosthodontic Society Jul 2024The aim of this umbrella review was to systematically review the systematic reviews on antagonist enamel wear opposing zirconia crowns compared to other ceramics and...
AIM
The aim of this umbrella review was to systematically review the systematic reviews on antagonist enamel wear opposing zirconia crowns compared to other ceramics and natural enamel.
SETTINGS AND DESIGN
This was an umbrella review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.
MATERIALS AND METHODS
An electronic search of PubMed, Cochrane Central, EBSCOhost, and Google Scholar search engines for articles published from January 1, 2013, to January 1, 2023, was conducted using keywords "enamel wear," "zirconia," "feldspathic," "dental ceramics," and "Y-TZP" to identify systematic reviews on antagonist enamel wear opposing zirconia crowns compared to other ceramics and natural enamel.
STATISTICAL ANALYSIS USED
Qualitative analysis.
RESULTS
A total of 86 articles were obtained through electronic search, of which four articles were selected after abstract screening that met the inclusion criteria for evaluating antagonist enamel wear. As compared to feldspathic groups, zirconia had substantially less antagonist wear, while surface polishing exhibited less enamel wear than glazing. Because of the heterogeneity in study design, measurement methods, and outcome variables, a meta-analysis was not possible.
CONCLUSIONS
Over time, the opposing enamel wear caused by polished monolithic zirconia will be either equal to or less than that of natural enamel wear. Polished monolithic zirconia also maintains lower values of enamel wear compared to metal ceramics, feldspathic porcelains, and lithium disilicate.
Topics: Humans; Ceramics; Crowns; Dental Enamel; Tooth Wear; Zirconium
PubMed: 38946503
DOI: 10.4103/jips.jips_32_24 -
Journal of Oleo Science 2024Herein, we evaluated friction dynamics of human skin treated with polyacrylic acid aqueous solutions or gel creams using a sinusoidal motion friction evaluation system...
Herein, we evaluated friction dynamics of human skin treated with polyacrylic acid aqueous solutions or gel creams using a sinusoidal motion friction evaluation system to demonstrate the effect of treatment with polymer aqueous solutions on human skin. A polymer aqueous solution or gel cream was applied to the inner forearms of 10 subjects to evaluate temporal changes in friction force under sinusoidal motion. Water content, skin viscoelasticity, and transepidermal water loss were also simultaneously measured to determine the effects on skin conditions. When human skin was treated with the polymer aqueous solution, the friction coefficient immediately after treatment was 0.69-0.99 and the delay time δ, a normalized parameter of the time difference in the delayed response of friction to the movement of the contact probe divided by the friction time T for one round trip, was 0.171-0.179, which was greater than that of untreated skin. This increase was caused by the swelling and softening of the stratum corneum caused by the penetration of water in the polymer aqueous solution, which increased true contact area between the skin and contact probe. A significant difference was observed in the friction coefficient of the skin immediately after treatment with different polymer aqueous solutions. Among polymers (P1-P4), P4, which has a low-salt resistance and low yield stress, had the lowest friction coefficient because of collapsing of the polymer network structures by shearing and reduced viscosity owing to salts on human skin. The skin treated with a gel cream also exhibited a greater friction coefficient than the untreated skin immediately after treatment and 90 min later. This phenomenon can be caused by the occlusive effect of the oil in the gel cream.
Topics: Humans; Friction; Water; Viscosity; Solutions; Acrylic Resins; Skin; Elasticity; Adult; Female; Male; Polymers; Skin Cream; Gels; Water Loss, Insensible
PubMed: 38945920
DOI: 10.5650/jos.ess24036 -
Dental Materials Journal Jun 2024This study investigated the usefulness of a dental laboratory polymerization unit with light-emitting diode (LED) as a light source. The depth of cure (n=15), water...
This study investigated the usefulness of a dental laboratory polymerization unit with light-emitting diode (LED) as a light source. The depth of cure (n=15), water absorption and solubility (n=9) of two indirect composite materials (Cesead N and Solidex Hardura) were evaluated by five dental laboratory polymerization units (LED Cure Master, Twinkle LED, α-Light V, α-Light II, and Hyper LII). Statistical analysis was performed by one-way ANOVA and Tukey test or non-parametric tests. Comparison of light sources for curing depth showed that metal halide had the highest value, followed by the LED group with similar values, and halogen lamps with the lowest value. The water absorption and solubility of the composite specimens polymerized with the three LED laboratory polymerization units were within the ISO recommended limit.
PubMed: 38945865
DOI: 10.4012/dmj.2023-260 -
Dental Materials Journal Jun 2024Laboratory evidence has shown that 45S5 bioglass can help in dental remineralization, so its incorporation into resin-modified glass ionomer cement (RMGIC) has been...
Laboratory evidence has shown that 45S5 bioglass can help in dental remineralization, so its incorporation into resin-modified glass ionomer cement (RMGIC) has been studied. This randomized clinical trial aimed to determine the efficacy of RMGIC enriched with 10% 45S5 bioglass (RMGIC/45S5) in preventing the progression of moderate caries lesions. Sixty-six permanent molars with moderate caries lesions, were randomly sealed with RMGIC or RMGIC/45S5. After 1, 3-6 months, patients' oral health, material behavior, and caries evolution were evaluated. Chi-square and Fisher's exact test was employed. After one month, the RMGIC showed higher total retention and better clinical performance compared to RMGIC/45S5, both showed a predominance of sealed teeth or without caries progression. After 6 months, no materials retention, quality and caries progression difference was observed for both materials. Short-term clinical follow-up reveals worse retention and quality of RMGIC/45S5, only after 6 months no clinical/microscopic differences are observed between the materials.
PubMed: 38945864
DOI: 10.4012/dmj.2023-261 -
The Journal of Prosthetic Dentistry Jun 2024Artificial intelligence has been used to enhance the digitalized workflow, especially when undergoing complex oral rehabilitations. However, the reliability of real-time...
STATEMENT OF PROBLEM
Artificial intelligence has been used to enhance the digitalized workflow, especially when undergoing complex oral rehabilitations. However, the reliability of real-time jaw motion registration devices is unclear, and no standard measurement method of the sagittal condylar inclination (SCI) and Bennett angle (BA) has been established.
PURPOSE
The purpose of this clinical study was to compare and evaluate the reliability of the SCI and BA values recorded by using 2 different digital devices.
MATERIAL AND METHODS
A total of 17 participants, aged between 20 and 30 years (10 women and 7 men) were included in the study. For each participant, the Cadiax Compact 2 and MODJAW tracking devices were used to measure the SCI and BA values at 3 mm and 5 mm of condylar displacement during 3 separate recording sessions. The intraclass correlation coefficient (ICC) was used to assess the reliability of the recordings. Comparisons between the devices were performed with the Wilcoxson rank-sum test (α=.05). The Bland-Altman plot was used to evaluate the quantitative agreement between the 2 devices.
RESULTS
All ICC intrarater reliability values for Cadiax and MODJAW were higher than 0.90. Both at 3 and 5 mm, the SCI measurements were higher for MODJAW registrations than for those recorded by Cadiax. The Bland-Altman plot showed that the SCI values were higher for MODJAW than for Cadiax by 5.9 (95% CI 3.9 to 8.2) and that the BA differences between the MODJAW and the Cadiax were not consistent with the measured value.
CONCLUSIONS
Excellent reliability was found with the MODJAW and Cadiax recordings. The SCI and BA values for MODJAW measurements were higher at 3 mm and 5 mm than those acquired with Cadiax. MODJAW showed higher values than Cadiax, and the discrepancies were more pronounced for 3 mm than for 5 mm of condylar displacement, highlighting the need for precision in measurements at lower ranges of motion.
PubMed: 38945794
DOI: 10.1016/j.prosdent.2024.05.014