Clinical Longevity Research Articles

Research of Optical Properties and Biocompatibility in Different Zones of Multilayered Translucent Zirconia on Hydrothermal Aging.

We assessed the changes in optical properties and biocompatibility of transition zones in multilayered translucent monolithic zirconia exposed to prolonged hydrothermal aging and compared the results to those with different yttrium oxide contents. Four types of zirconia blocks from IPS e.max ZirCAD were used: 3Y-TZP e.max ZirCAD LT (ZL), 4Y-TZP e.max ZirCAD MT (ZM), 5Y-TZP e.max ZirCAD MT Multi (ZT), and 3Y/5Y-TZP e.max ZirCAD Prime (ZP). A total of 120 specimens (15.0 mm diameter and 1.5 mm height) were fabricated and divided into three groups (n = 10). The aging process for the specimens was conducted in an autoclave set to 134 °C and 0.2 MPa, with durations of 0 h (control), 5 h (first aged), and 10 h (second aged). The optical properties and biocompatibility were analyzed, followed by a statistical analysis of the data (α = 0.05). Before and after aging, ZL and ZP exhibited the lowest color changes. ZT exhibited the highest average transmittance and translucency parameter values, while ZL had the lowest. The water contact angle test showed the highest value in ZM and lowest in ZL across all the aging stages. ZL, ZM, and ZP showed a considerable decrease in the water contact angle; however, ZT did not. A cell counting kit-8 assay showed ZL had the highest value, while ZM had the lowest. A filamentous actin test exhibited the highest value in ZL and lowest in ZM. In the vinculin analysis, ZL and ZT exhibited the lowest values, whereas ZM and ZP had the highest. 3Y/5Y-TZP exhibited a balanced performance across critical parameters, such as color stability, translucency, and biocompatibility, aligning with 3Y-TZP. While 5Y-TZP demonstrated superior translucency, it confirmed the lowest color stability, whereas 3Y-TZP achieved the highest biocompatibility. These properties provide clinicians with a reliable material option that ensures superior esthetic outcomes and long-term prognosis, ultimately contributing to improved patient satisfaction and clinical longevity.

UV Exposure Time Optimization for Enhanced Conversion, Hardness, and Flexural Strength in UDMA/TEG-DMA Composite Resins

This study examines the effects of varying ultraviolet (UV) exposure times on the properties of UDMA/TEG-DMA composite resins, focusing on degree of conversion, surface morphology, water absorption, shrinkage, hardness, and flexural strength. Composite resin samples were exposed to UV light for 30, 60, 90, and 120 min. The degree of conversion was assessed using Fourier Transform Infrared Spectroscopy (FTIR). Surface morphology was analyzed via Scanning Electron Microscopy (SEM). Water absorption and shrinkage were measured following standard procedures, while mechanical properties, including hardness and flexural strength, were evaluated using a Vickers hardness tester and a 3-point bending test, respectively. The results indicate that a UV exposure time of 90 min optimizes the composite resin properties, achieving the highest degree of conversion at 77 %, optimal surface morphology, minimal water absorption and shrinkage, and superior mechanical properties, including maximum flexural strength and hardness. In contrast, both shorter and longer UV exposure times detrimentally affected these properties, with prolonged exposure causing thermal degradation and reduced performance. This research underscores the importance of precise UV curing time control to enhance the performance and durability of UDMA/TEG-DMA composite resins, providing valuable insights and practical guidelines for their application in dental and industrial fields. HIGHLIGHTS The incorporation of UDMA/TEG-DMA in composite resin formulations significantly enhanced mechanical properties such as flexural strength and modulus. Exposure to UV light affected the degree of conversion of the resin, impacting its polymerization kinetics and potentially influencing long-term durability. The study revealed notable changes in surface morphology, indicating potential implications for bonding characteristics and aesthetic outcomes. Investigating water absorption and shrinkage behavior provided insights into material stability and dimensional changes over time, critical for clinical longevity and patient satisfaction. GRAPHICAL ABSTRACT

Impact of S-PRG/Giomer and Bulk-Fill technologies on the hygroscopic profile of resin composites under erosive condition

The emergence of new resin composites (RCs) incorporating bioactive ingredients and/or used as bulk-fill materials aims to enhance restorative potential beyond just the mechanical properties. However, this innovation may affect their performance under clinically simulated conditions, such as erosive challenges (EC). This study evaluated the impact of different technologies on the hygroscopic properties of RCs. The evaluated materials were: Gold Label-GL (resin-modified glass-ionomer cement-control); Filtek Z350-FZ (no bioactive control); Filtek One Bulk-FO (bulk-fill); Beautifil II-BII (bioactive/S-PRG); Beautifil Bulk-BB (bioactive/S-PRG + bulk-fill). Disk-shaped specimens (10mmx1mm) were prepared and evaluated by: 1) water sorption-WS and solubility-WSB (n=10); 2) wettability-W (n=6); 3) surface microhardness-SM (n=6); 4) qualitative surface analysis by SEM (n=3). Except for WS and WSB, tests were performed before and after EC. Data were analyzed by two-factor ANOVA and Tukey tests (p<0.05). Positive WS and negative WSB were observed for all materials. In terms of W, GL>BII>FZ>BB>FO. GL and BB exhibited similar/lower SM. EC hampered SM for all materials. It may be concluded that the composition and proportion of monomers have a greater influence on the hygroscopic profile of resin composites than the incorporation of bioactive components. While renewed technologies have introduced components to enhance the performance and practicality of resin composites, actual clinical longevity depends on challenges such as erosive conditions. Bioactive ingredients seem to be beneficial without impairing the hygroscopic profile, whereas the monomers can interfere.

Influence of different viscosity and chemical composition of flowable composite resins: A 48-month split-mouth double-blind randomized clinical trial

ObjectivesTo evaluate the clinical performance of two flowable composites based on methacrylate and one based on ormocer in treating non-carious cervical lesions (NCCLs) after 48-month evaluation in a split-mouth double-blind clinical study design. MethodsA total of 183 restorations were performed on NCCLs using a universal adhesive system (Futurabond U, Voco GmbH) with selective enamel etching on 27 participants: two participants received twelve restorations each, three received nine restorations each, and 22 participants received six restorations each. Three different flowable composites were employed (n = 61): a low-viscosity methacrylate-based composite (GrandioSO Flow, LVM), a high-viscosity methacrylate-based composite (GrandioSO Heavy Flow, HVM), and an ormocer-based flowable composite (Admira Fusion Flow, ORM). All restorations were evaluated using FDI and USPHS criteria after 48 months. Statistical analysis was conducted using Kaplan-Meier Survival analysis and Kruskal-Wallis analysis of variance rank (α = 0.05). ResultsAfter 48 months, 17 restorations were lost: LVM 6, HVM 9, ORM 2. The retention rates (95 % confidence interval) were 89.4 % for LVM, 80.4 % for HVM, and 95.6 % for ORM, with a significant difference between HVM vs. LVM and HVM vs. ORM (p < 0.05). Minor defects were observed in 30 restorations for marginal staining criteria (LVM 12, HVM 10, ORM 8) and in 71 restorations for marginal adaptation criteria (LVM 24, HVM 20, ORM 27) without significant difference between groups (p > 0.05). No restorations showed postoperative sensitivity or recurrence of caries. SignificanceThe increased viscosity of flowable composites could reduce the clinical longevity in NCCLs after 48 months. Ormocer-based and low-viscosity methacrylate-based flowable composites showed a successful clinical performance in NCCLs after 48 months.

CLINICAL LONGEVITY OF DIRECT RESIN-BASED COMPOSITE VENEERS ON ANTERIOR TEETH

Introduction: The growing demand for smiles' aesthetic improvement leads direct resin-based composite (RBC) veneers to gain increasing ground when it comes to renewing patients' dental appearance, mainly due to RBC cosmetic properties and the minimally invasive approach related to them. However, it is essential to know the success and survival rates and the main causes of failure of this technique. Objective: The aim of this study was to study the clinical longevity of direct RBC veneers on anterior teeth. Method: PICO framework guided the search strategies in the Pubmed, Google Scholar, and Periódicos Capes databases using a combination of the terms "composite resins, direct veneers, dental veneers, and longevity". Inclusion criteria was clinical follow-up studies of least 6 months, published in English from 2003 onwards, evaluating the performance of RBC veneers in anterior teeth. Books, book chapters, theses, editorials, in vitro studies, and articles that did not provide clinical follow-ups of RBC veneers were excluded. Using language (English) filter, 636 scientific articles were found, which were analyzed following the PRISMA statement and discarded if they did not meet the criteria. At the end, only four articles were selected, and their data collected. Conclusion: There was great variability in the time and criteria used to evaluate restorations in different studies, but the literature considers that direct RBC veneers have an acceptable clinical longevity, but may require repair appointments, and the main cause of failure.

Flowable resin-based composites modified with chlorhexidine-loaded mesoporous silica nanoparticles induce superior antibiofilm properties

Clinical failure of dental resin-composite restorations is mainly due to bacterial-mediated secondary caries formation. Therefore, the development of a flowable resin-composite material having inherent antibacterial properties is crucial to enhance the durability of dental restorations. Herein, dental flowable resin-composite material was modified with chlorhexidine-loaded mesoporous silica nanoparticles (CHX-MSN) to induce in situ antibacterial properties against S. mutans. Mesoporous silica nanoparticles loaded with chlorhexidine (CHX-MSN) were formulated and characterized for drug-loading/encapsulation efficiency, morphology by electron microscopy, and infrared spectral analysis. CHX-MSN were incorporated into the flowable composite material at different concentrations of 1, 5, and 10% (w/w) and examined at two time points (baseline and 3 months in artificial saliva). The CHX-MSN modified composites exhibited an initial CHX release burst followed by a steady release up to 30 days. The antimicrobial efficacy of the modified composites was evaluated by crystal violet assay, MTT assay, and confocal laser scanning microscopy. In addition to measuring the degree of conversion and cytotoxicity, the mechanical properties were characterized by surface microhardness and flexural strength. The modified composites demonstrated a significant increase in antimicrobial properties compared to the unmodified control (p < 0.05) which is dependent on the concentration of the CHX-MSN nanoparticles. In addition, the modified composites possessed acceptable biocompatibility without adversely affecting mechanical properties and degree of conversion up to 5% addition of CHX-MSN nanoparticles. This study introduced a protocol to develop resin-based flowable dental composite material having superior antibacterial property against cariogenic biofilms aiming for enhancing clinical longevity of dental restorations.Graphical

Flexural strength and degree of conversion of universal single shade resin-based composites

Background/purposeRecently, a group of universal single-shade resin-based composites (RBCs) has been developed to simplify the process of shade selection. Excellent mechanical and physical properties are crucial for the ultimate success and clinical longevity of restorations. Therefore, evaluating the properties of the single-shaded RBCs is imperative. This study aimed to determine the flexural strength (FS) and degree of conversion (DC) of universal single-shade RBCs. Materials and methodsIn this study, four commercial RBCs were used; three universal single-shade RBCs; Omnichroma (OC), Charisma® Diamond ONE (CD), and Vittra APS Unique (VU), and a conventional nanohybrid composite Filtek™ Z250 XT (FT) which was used as a control. Sixty composite beams and 40 composite discs were used for FS and DC, respectively. A universal test machine with a three-point bending test was used to measure the FS, whereas the DC was measured using a Fourier-transform infrared spectrometer (FTIR). Three fractured specimens from each resin composite group were qualitatively analyzed using scanning electron microscopy. ResultsANOVA was used to compare the mean values of FS and DC among the four RBCs (OC, CD, VU, and FT). Highly significant differences were observed in the mean FS and DC values (F = 673.043, p < 0.001 and F (=782.4, p < 0.0001), respectively. The highest FS was observed in the CD group, followed by FT and VU groups; the lowest value was observed in the OC group. In addition, a statistically significant difference was identified in DC values. The highest DC value was observed in VU, followed by OC and CD, and the lowest DC value was observed in FT. ConclusionUniversal single-shade RBCs demonstrated a good FS, except for OC, which exhibited a significantly low FS. The DC of the universal single-shade RBCs was higher than that of the conventional nanohybrid composite restorative material.

Clinical Longevity of Obturators in Patients with Jaw Defects: a Retrospective Cohort Study.

The primary objective of the present retrospective clinical study was to determine the survival time of obturators while analyzing possible influencing factors. This retrospective clinical cohort study analyzed the influence of various clinical factors on the survival probability of obturators and their follow-up outcomes using Kaplan‒Meier analysis. A total of 76 patients with 115 obturators were included in the study (47 men and 29 women, mean age 58.1 ± 18.1years). The mean observation time was 3.0 ± 4.5years (maximum 26.3years). A total of 40.9% (47) of all obturators observed had to be replaced. The survival rate after 5years was 79.5% for telescopic-crown-retained tooth-supported obturators, 86.9% for telescopic-crown-retained implant-supported obturators, 58.8% for removable full denture obturators, 22.1% for clasp-retained obturators and 0.0% for splints. The type of attachment, attendance at a regular follow-up and defect cause significantly influenced the survival of the obturators (p < .05). The findings obtained in this study support the recommendation of using implant-supported obturators. Telescopic-crown attachments, either tooth- or implant-supported, seem to be favorable in terms of survival time. Attendance at a strict follow-up program seems to have a major influence on the longevity of the obturators. The use of implant-supported obturators to cover permanent oral and maxillofacial defects is highly recommended. Additionally, the use of telescopic-crown attachments seems to be favorable in terms of survival time. Clasp-retained obturators and surgical splints should be used primarily for temporary restorations due to their shorter survival times.

Effect of Bonding Agents on the Shear Bond Strength of Tooth-colored Restorative Materials to Dentin: An In Vitro Study.

The aim of the study is to determine the difference in the shear bond strengths to dentin among dental composite (Filtek Z350®, 3M), compomer (Dyract Flow®, Dentsply) and Giomer (Beautifil®, Shofu) with 3MTM Single BondTM Universal Adhesive (SBU) (7th generation, self-etch, single solution adhesive) and AdperTM Single Bond 2 Adhesive (ASB) (5th generation, total-etch, two solution adhesive). Sixty extracted human permanent teeth were collected, cleansed of debris, and placed in distilled water. The samples were segregated into two groups depicting the two bonding agents-AdperTM (ASB) and 3MTM Single Bond Universal (SBU) and sub-grouped into three groups depicting the three restorative materials (Composite, Giomer, and Compomer) used. Groups were respresented as follows: Group I-ASB + Composite; Group II-ASB + Giomer; Group III-ASB + Compomer; Group IV-SBU + Giomer; Group V-SBU + Compomer; Group VI-SBU + Composite. After applying the bonding agent as per the manufacturer's instructions, following which the restorative material was placed. A Universal Testing Machine (Instron 3366, UK) was employed to estimate the shear bond strength of the individual restorative material and shear bond strengths were calculated. Composite bonded with SBU (group VI) displayed the greatest shear strength (11.16 ± 4.22 MPa). Moreover, Giomers and flowable compomers displayed better bond strengths with ASB compared with their SBU-bonded counterparts. These results mark the importance of careful material selection in clinical practice and the bonding agent used to achieve optimal bond strength and enhance the clinical longevity and durability of dental restorations. From a clinical perspective, to avoid a compressive or a shear failure, it would be preferrable to use a direct composite restorative material with SBU (Single bond universal adhesive, 7th generation) to achieve maximum bond strength. How to cite this article: Kuchibhotla N, Sathyamoorthy H, Balakrishnan S, et al. Effect of Bonding Agents on the Shear Bond Strength of Tooth-colored Restorative Materials to Dentin: An In Vitro Study. J Contemp Dent Pract 2024;25(3):245-249.

Clinical Longevity of Preoperative Injection of Superparamagnetic Iron Oxide Nanoparticles for Delayed Sentinel Lymph Node Biopsy.

Diagnosis of ductal carcinoma in situ (DCIS) represents about 25% of newly diagnosed breast cancers. There is debate about the benefit of sentinel lymph node biopsy (SLNB) for further staging and guidance of therapy in patients with DCIS. Current guidelines recommend SLNB for patients undergoing breast-conserving therapy (BCT) for DCIS. Utilizing superparamagnetic iron oxide (SPIO) nanoparticles as a tracer may allow for a delayed SLNB (d-SLNB), typically within a month of injection. We present our experience with a patient who due to complications from surgery could not complete her d-SLNB for 165days. The SPIO tracer remained active in the lymph node and remained clinically useful for this five and a half month gap from time of injection. Further study is needed to determine the clinical longevity of SPIO in a lymph node.

Effect of Reduced-Step Polishing Systems on Color Stability of Nanocomposites Submitted to Thermocycling Staining with Common Beverages - An In Vitro Study.

Long-term color stability of composite resins is one of the most important factors influencing the clinical longevity of aesthetic restorations. This study evaluated the effect of novel reduced steps and gold standard multiple steps polishing systems of two composite resins; a nano-filled (Filtek Z350XT) versus a supra-nanofill (Palfique LX5) on their color stability after submitting to thermocycling with common beverages. Sixty disc-shaped specimens were fabricated from both composite resins ( n = 30). From each material, ten specimens acted as the control group (Mylar strip), ten specimens were polished with Sof-Lex Diamond spirals, and ten were polished with Super-Snap X-Treme discs. All the specimens were thermocycled with staining solutions. Color was measured by a spectrophotometer before and after thermocycling and color difference (ΔE*) was calculated. One-way analysis of variance followed by Tukey's post-hoc test and independent t -test ( α = 0.05) were used. A significantly highest color change was recorded for both control subgroups ( P < 0.05), and the Sof-Lex Diamond spiral showed significantly the lowest color change ( P < 0.05). Both the control and Sof-Lex Diamond spiral subgroups of Palfique LX5 produced significantly lower color change compared with subgroups of Filtek Z350 ( P < 0.05). Sof-Lex Diamond spiral polishing system provided the least color difference for both composites, while there was no significant difference between the materials when the Super-Snap X-Treme polishing system was used.

Stress distribution on teeth restored with veneers using various incisal preparation designs: A 3D finite element analysis study

Statement of problemThe type of veneer preparation is often chosen according to the patient’s tooth structure and occlusion. Taking biomechanics into account in this decision-making process provides the clinician with more technical information on how to improve the clinical longevity of restorations. However, biomechanical analyses of veneer preparation designs are sparse. PurposeThe purpose of this 3-dimensional (3D) finite element analysis with microcomputed tomography (µCT) data obtained from realistic models was to assess the influence of different preparations for ceramic and composite resin veneers on restoration and resin layer stress distribution. Material and methodsFour replicas of a central incisor were printed and prepared for laminate veneers with 4 different incisal edge designs: shoulder (SH), palatal chamfer (PC), palatal chamfer and oblique fracture involving the distal angle (OF-PC), and palatal chamfer involving horizontal incisal fracture (IF-PC). After fabrication and cementation of the veneers, the restored replicas were assessed with µCT, and 3D finite element models were built. A 100-N load was applied on the palatal surface at 60 and 125 degrees relative to the longitudinal axis. Maximum principal stress and stress distribution on the veneers, cement layer, and tooth structure were calculated and analyzed. ResultsThe SH preparation exhibited better stress distribution than the PC preparation, and the cement layer and the veneer were subjected to lower stress. The IF-PC preparation had better stress distribution than the OF-PC. The shoulder and IF-PC showed higher stress on laminate veneers, but lower stress on the cement layer. Ceramic veneers exhibited lower stress than composite resin veneers. ConclusionsThe different incisal preparations for laminate veneers influenced stress distribution on restorations and on the resin cement layer. The shoulder type preparation showed better stress distribution and the composite resin veneers showed unfavorable results compared with the ceramic veneers.

Flexural properties and fatigue limit of 3D-printed and milled resin-based materials.

The purpose of this study was to evaluate the flexural strength (FS), flexural modulus (FM), and fatigue limit (FL) of 3D-printed resin-based polymers and composites and compare them to 3D-printed composites. A bar-shaped specimen (25×2×2mm) was CAD designed according to ISO 4049:2019, and 60 duplicates of the 3D model were nested at a 45-degree angle with the printing platform and 3D-printed with three materials: denture teeth resin (Denture Teeth, Formlabs), temporary crown and bridge resin (Temporary CB, Formlabs), and composite (Flexcera Smile Ultra+, Desktop Health). The 3D model was also imported into a dental CAM software, duplicated 60 times, nested, and milled from a 3D-milled composite puck (Ivotion Denture Teeth, Ivoclar). All specimens were post-processed following the manufacturer's recommendation. The specimens were then subjected to a three-point bending test until failure using a Universal Testing Machine at a crosshead speed of 0.75mm/min, and FS and FM were calculated. The remaining thirty specimens were tested for Fatigue Limit using the staircase approach starting at 50% FS maximum up to 1.2M cycles at 10Hz. The data were analyzed using one-way ANOVA and the Weibull distribution (α = 0.05). The results showed that Ivotion and Flexcera had higher FS (110.3 ± 7.1MPa and 107.6 ± 6.4MPa, respectively) and FM (3.3 ± 0.1GPa and 3.0 ± 0.2GPa, respectively) compared to the 3D-printed Denture Teeth (FS = 66.4 ± 18.5MPa and FM = 1.8 ± 0.1GPa) and Temporary CB (FS = 79.6 ± 12.1MPa and FM = 2.7 ± 0.4GPa). Weibull analysis showed that the Ivotion and Flexcera had a more uniform and narrower spatial distribution of defects (m: 27.98 and 29.19) than the printed materials, which had m values of 8.17 and 4.11 for Temporary CB and Denture Teeth, respectively. Although no differences were found in the static properties (FS and FM) between Ivotion and Flexcera, Ivotion presented a higher endurance limit than Flexcera (51.43 vs. 40.95MPa). The Temporary CB presented 21.08MPa and Denture Teeth presented 17.80MPa of endurance limit. 3D-milled (Ivotion Denture Teeth) and 3D-printed (Flexcera Smile Ultra+) composites outperformed 3D-printed resins (Formlabs Denture Teeth and Temporary Crown & Bridge) in terms of flexural properties and fatigue resistance. 3D-milled (Ivotion) and 3D-printed (Flexcera) composites exhibited similar flexural properties, but 3D-milled composites showed a 25% higher fatigue endurance limit, suggesting improved clinical longevity.

Evaluating Glass Ionomer Cement Longevity in the Primary and Permanent Teeth-An Umbrella Review.

The aim of this umbrella review was to evaluate the longevity of glass ionomer cement (GIC) as a restorative material for primary and permanent teeth. Research in the literature was conducted in three databases (MedLine/PubMed, Web of Science, and Scopus). The inclusion criteria were: (1) to be a systematic review of clinical trials that (2) evaluated the clinical longevity of GICs as a restorative material in primary and/or permanent teeth; the exclusion criteria were: (1) not being a systematic review of clinical trials; (2) not evaluating longevity/clinical performance of GICs as a restorative material; and (3) studies of dental restorative materials in teeth with enamel alterations, root caries, and non-carious cervical lesions. Twenty-four eligible articles were identified, and 13 were included. The follow-up periods ranged from 6 months to 6 years. Different types of GICs were evaluated in the included studies: resin-modified glass ionomer cement (RMGIC), compomers, and low- and high-viscosity glass ionomer cement. Some studies compared amalgam and composite resins to GICs regarding longevity/clinical performance. Analyzing the AMSTAR-2 results, none of the articles had positive criteria in all the evaluated requisites, and none of the articles had an a priori design. The criteria considered for the analysis of the risk of bias of the included studies were evaluated through the ROBIS tool, and the results of this analysis showed that seven studies had a low risk of bias; three studies had positive results in all criteria except for one criterion of unclear risk; and two studies showed a high risk of bias. GRADE tool was used to determine the quality of evidence; for the degree of recommendations, all studies were classified as Class II, meaning there was still conflicting evidence on the clinical performance/longevity of GICs and their recommendations compared to other materials. The level of evidence was classified as Level B, meaning that the data were obtained from less robust meta-analyses and single randomized clinical trials. To the best of our knowledge, this is the first umbrella review approaching GIC in permanent teeth. GICs are a good choice in both dentitions, but primary dentition presents more evidence, especially regarding the atraumatic restorative treatment (ART) technique. Within the limitation of this study, it is still questionable if GIC is a good restorative material in the medium/long term for permanent and primary dentition. Many of the included studies presented a high risk of bias and low quality. The techniques, type of GIC, type of cavity, and operator experience highly influence clinical performance. Thus, clinical decision-making should be based on the dental practitioner's ability, each case analysis, and the patient's wishes. More evidence is needed to determine which is the best material for definitive restorations in permanent and primary dentition.

Clinical Longevity of Sonicated and Unsonicated Composite Resin Restorations in Posterior Permanent Teeth: A Systematic Review and Meta-Analysis

Clinical Longevity of Sonicated and Unsonicated Composite Resin Restorations in Posterior Permanent Teeth: A Systematic Review and Meta-Analysis

Clinical longevity of metallic versus fiberglass intraradicular posts: a systematic review

Clinical longevity of metallic versus fiberglass intraradicular posts: a systematic review

Clinical Longevity of Ceramic Veneers Bonded to Teeth with Aged Composite Restorations (Literature Review)

In this study the literature was reviewed to investigate the clinical outcome and longevity of anterior ceramic laminate veneers bonded to prior existing composite restorations. Clinical studies had investigated the survival of anterior ceramic laminate veneers adhered to teeth structures for at least 5 years of follow-up. This review has traced the studies which recorded the clinical longivity of porcelain laminate veneers bonded over old composite restorations; also the main reasons associated with restorations failure were searched. Sources in PubMed, Scopus, and Cochrane databases were searched in English language and without restriction on date. three reviewers screened titles and/or abstracts of 195 studies, all screened articles did not met the inclusion criteria of this review; which to have five years and more follow up in clinical retrospective or prospective studies, for that reason we have selected the most In vivo could possibly more related and the related In vitro studies. Within the limitation of this review, the clinical evidence for the practice of ceramic laminate veneers bonded over prior aged composite restorations is not strong. There is information lack about the long duration follow up for such treatment modality. The approach of replacing the prior existing composite restoration with new ones could be a wise option but using extended veneer design might be a wiser alternative. We recommend more clinical trials for long enough duration to evaluate the long success of ceramic laminate veneers that will be adhered to prior existing composite restorations.

An in vitro study measuring marginal gaps of inlay restorations fabricated from different CAD-CAM materials after thermocycling

BackgroundMany monolithic machined materials have been introduced and provided a suitable mechanical and physical properties for inlay restorations. However, there is shortage in the studies evaluating the marginal adaptation using these materials.PurposeThis study aimed to compare the effect of fabricating inlay restorations from 3 different CAD-CAM materials on marginal gaps before and after thermocycling.Materials and methodsSixty human premolars were randomly divided into 3 groups (n = 20) according to the material used: (e.max CAD, Ivoclar AG, Schaan, Liechtenstein), (HC, Shofu, Koyoto, Japan) and (Brilliant Crios, Coltene, Altstätten, Switzerland) (n = 20). A scanning electron microscope (SEM) (JSM- 6510 lv, JEOL, Tokyo, JAPAN) was used to for measuring the marginal gaps after cementation of inlay restorations. The magnification was adapted to 250x. Marginal gaps were revaluated with SEM after thermocycling. The temperatures of baths were 5 and 55 °C was applied for a total of 5000 cycles. All data were statistically analyzed by using ANCOVA to demonstrate if there were any statistically significant differences between the gap measures after thermocycling of the three independent (unrelated) groups. A Bonferroni adjustmen was used to perform post hoc analysis (α = 0.05).ResultsPost-intervention marginal gap was statistically significantly lower in group EX (110.8 μm) which was statistically significant compared with group SF (112.5 μm) (mean difference=-1.768, P = .007) and group BR (113 μm) (mean difference=-2.272, P = .001), however, in. comparing SF and BR groups, there was no significant difference (mean difference=-0.5, P = .770).ConclusionsThermocycling affected the marginal gaps of composite based restoration and resin-modified ceramics widely. However, it had a very small effect on glass ceramics marginal adaptation.Clinical implicationsThe marginal gaps of CAD-CAM inlays varied according to material used (ceramic based, combination, or resin based). Thermocycling has a minor effect on the marginal adaptation of lithium disilicate glass-ceramic inlays, where it affected the margin of resin-modified ceramic and composite based inlays greatly. Using lithium disilicate glass-ceramic might improve the clinical longevity of inlay restored teeth.

Color Stability, Gloss Retention, and Surface Roughness of 3D-Printed versus Indirect Prefabricated Veneers.

The long-term color stability and surface properties of anterior laminate veneers are among the crucial factors affecting the clinical longevity of aesthetic restorations. Novel 3D-printed materials are being introduced as definitive restorative treatment. In light of the existing variety of indirect yet minimally invasive composite resin veneers, research on their surface properties is warranted. This in vitro study evaluated the effect of artificial aging by immersion in different staining solutions on the color changes, gloss, and surface roughness (Ra) of 3D-printed veneers compared to the prefabricated resin composite veneer systems (PRCVs) manufactured by Componeer and Edelweiss. Moreover, this study compared the effects of two methods for stain removal: repolishing with Sof-Lex disks and in-office bleaching with 40% hydrogen peroxide. The veneers (n = 24) were randomly divided according to the immersion solutions used, i.e., tea and coffee. Colorimetric measurements, surface roughness, and surface gloss were determined before and after staining and surface treatment with either in-office bleaching or surface polishing. The data were statistically analyzed using two-way ANOVA followed by the Tukey's post hoc test (α = 0.05). Artificial aging with immersion in staining solutions led to significant color changes, increased surface roughness, and gloss reduction in all materials (p < 0.05). The 3D-printed veneers showed higher ΔE values (coffee = 10.112 ± 0.141) and (tea = 10.689 ± 0.771) compared to baseline after 7 days of aging. The 3D-printed veneers had a statistically significant surface roughness Ra (0.574 µm ± 0.073). The gloss was >70% in all groups at baseline; these values dropped in all groups after 7 days of artificial aging. After the stain-removing procedures, the ΔE values decreased in all tested veneers. That being said, they failed to return to the baseline values, and both stain-removing methods were found to have an adverse effect on surface roughness and gloss retention in all tested veneers.

A Retrospective Study on the Fracture Toughness of the Coronal Restorations in Endodontically Restored Teeth. An Original Research.

The best treatment for the deeply carious tooth that cannot be restored is by the root canal therapy. This method has saved many patients from the loss of tooth. The common practice is either to deliver a full crown or close the access cavity with restoration. Hence in this study, the clinical longevity of the routine practice is tested for by analyzing the fracture toughness and the survival of the teeth that were restored endodontically with various materials. The hospital records were retrospectively evaluated from 2000 to 2010 for a decade. The demographics as well as the survival and the failure rates noted and compared for the various types of the restorations. The number of the walls of the teeth was also compared. Thousand teeth were considered in the study. Less than 7% of teeth had coronal fractures. Of the 93% teeth that had survived, the most common restoration was Individual post (+ crown) followed by GIC, amalgams, and crowns. The mean survival of the crown+ bridge & gold restoration was highest. The mean survival was 10 ± 2 years for the restored teeth without any fractures at the coronal level. The failure was greatest for the GIC followed by amalgam, and the variations when compared with other restorations were significant. There was no significant difference for the number of the walls on the crown; however, the number of walls present was proportional to the survival rate. The teeth that were covered with a crown were comparatively fracture resistant and had a better survival rate compared to other restorations. GIC showed highest fracture, and the post core with crown had the best survival. Restoration of the lost crown architecture and the reinforcement are the best methods that can be followed for the survivals.