Survival of Prosthodontic Restorations Luted with Resin-Based versus Composite-Based Cements: Retrospective Cohort Study

The purpose of this study was to evaluate clinical performance, survival, and complications of indirect composite inlays, onlays, and overlays on posterior teeth. Digital records of 282 patients treated between 2014 and 2018 were accessed and analyzed retrospectively. The included patients received 469 composite restorations luted with seven different resin-based types of cement, i.e., Filtek Ultimate Flow, Enamel Plus, Relyx Ultimate, Harvard Premium Flow, Relyx Unicem, Filtek Bulk Fill Flowable, and Filtek Ultimate. The restorations had been clinically and radiographically evaluated annually. The mechanical and clinical complications, e.g., debonding, fracture, and secondary caries, were evaluated and recorded. The examined restorations exhibited a high survival rate (84.9%), and failure was found in only 71 cases. Fracture was the most common cause (n = 36), followed by prosthetic work release (n = 19) and secondary caries (n = 16). There was a statistically significant difference between failure and cement material (Sig. < 0.001); the composite-based cements (87.2%) had a high survival rate compared to the resin-based cement (72.7%). Similarly, the cements with high viscosity (90.2%) had significantly higher survival rates than the low-viscosity cements (78.9%). Moreover, onlays showed higher longevity compared to overlays (Sig. = 0.007), and patients aged under 55 years showed less complications (Sig. = 0.036). Indirect composite restoration was a successful solution to tooth structure loss. The material of the cementation is an important part of the success. Higher survival rate was found in our study when the fixation materials with high viscosity were used, thus suggesting using these materials with indirect restorations. Composite-based cements had significantly higher survival rate than resin-based cements.

Effect of Cavity Cleanser With Long-Term Antibacterial and Anti-Proteolytic Activities on Resin–Dentin Bond Stability

ObjectiveSecondary caries caused by oral microbiome dysbiosis and hybrid layer degradation are two important contributors to the poor resin–dentin bond durability. Cavity cleansers with long-term antimicrobial and anti-proteolytic activities are in demand for eliminating bacteria-induced secondary caries and preventing hybrid layers from degradation. The objectives of the present study were to examine the long-term antimicrobial effect and anti-proteolytic potential of poly(amidoamine) dendrimers with amino terminal groups (PAMAM-NH2) cavity cleanser.MethodsAdsorption tests by attenuated total reflectance–infrared (ATR-IR) spectroscopy and confocal laser scanning microscopy (CLSM) were first performed to evaluate whether the PAMAM-NH2 cavity cleanser had binding capacity to dentin surface to fulfill its relatively long-term antimicrobial and anti-proteolytic effects. For antibacterial testing, Streptococcus mutans, Actinomyces naeslundii, and Enterococcus faecalis were grown on dentin surfaces, prior to the application of cavity cleanser. Colony-forming unit (CFU) counts and live/dead bacterial staining were performed to assess antibacterial effects. Gelatinolytic activity within the hybrid layers was directly detected by in situ zymography. Adhesive permeability of bonded interface and microtensile bond strength were employed to assess whether the PAMAM-NH2 cavity cleanser adversely affected resin–dentin bonding. Finally, the cytotoxicity of PAMAM-NH2 was evaluated by the Cell Counting Kit-8 (CCK-8) assay.ResultsAdsorption tests demonstrated that the binding capacity of PAMAM-NH2 on dentin surface was much stronger than that of 2% chlorhexidine (CHX) because its binding was strong enough to resist phosphate-buffered saline (PBS) washing. Antibacterial testing indicated that PAMAM-NH2 significantly inhibited bacteria grown on the dentin discs as compared with the control group (p &lt; 0.05), which was comparable with the antibacterial activity of 2% CHX (p &gt; 0.05). Hybrid layers conditioned with PAMAM-NH2 showed significant decrease in gelatin activity as compared with the control group. Furthermore, PAMAM-NH2 pretreatment did not adversely affect resin–dentin bonding because it did not decrease adhesive permeability and microtensile strength. CCK-8 assay showed that PAMAM-NH2 had low cytotoxicity on human dental pulp cells (HDPCs) and L929.ConclusionsPAMAM-NH2 cavity cleanser developed in this study could provide simultaneous long-term antimicrobial and anti-proteolytic activities for eliminating secondary caries that result from a dysbiosis in the oral microbiome and for preventing hybrid layers from degradation due to its good binding capacity to dentin collagen matrix, which are crucial for the maintenance of resin–dentin bond durability.

Clinical Evaluation of Glass-Lonomer Cement and Giomer for the Management of Cervical Caries

Background: Giomer is a unique class of restorative material has been introduced as the true hybridization of Glass Ionomer (GI) and composite resin and has the distinguishing feature of a stable surface pre-reacted glass ionomer. Glass Ionomer Cements (GIC) are also unique restorative materials with many uses in clinical practice and provide for caries-protective fluoride releasing at the margins of restorations, as well as their ability to have the fluoride within their chemical matrix recharged by outside exposure to other fluoride-containing materials. The present study aim at clinically evaluate the comparison between the glass Ionomer cement and Giomer for the management of cervical caries. Materials and methods: The study was a cross sectional comparative study which was carried out from 01 December 2018 to 31 November 2019 in the Department of Conservative Dentistry and Endodontics, Bangladesh Dental College, Dhanmondi, Dhaka. Total number of cases was 80. The patients were divided into two groups, half of the patient (Group-1) was treated with Glass Ionomer cement and half of the patient (Group-2) was treated with Giomer restoration. The post-operative sensitivity discoloration, dislodgement of filling material and secondary caries formation were recorded. All the patients were assigned and the data were analyzed statistically by SPSS version 21. p-value < 0.05 was taken as significant. Results: The study reveals 60% of the study population was within 41 to 50 years of age group (Group-1) and 62.5% were 51 to 60 years (Group-2) 45% in (Group-1) and 10% in (Group-2) had history of post filling sensitivity, 12% in (Group-1) and 5% in (Group-2) had discoloration after restoration, 2.5% had history of dislodgement of the filling in (Group-1), no history of dislodgement of the filling in (Group-2), 2.5% had history of secondary caries formation in (Group-1) and no history of Secondary caries formation in (Group-2). Conclusion: Patients were more approachable for Giomer restoration than Glass ionomer for the management of cervical caries over a period of 12 month. Chatt Maa Shi Hosp Med Coll J; Vol.20 (2); July 2021; Page 60-64

Metal Oxide Nanoparticles and Nanotubes: Ultrasmall Nanostructures to Engineer Antibacterial and Improved Dental Adhesives and Composites

Advances in nanotechnology have unlocked exclusive and relevant capabilities that are being applied to develop new dental restorative materials. Metal oxide nanoparticles and nanotubes perform functions relevant to a range of dental purposes beyond the traditional role of filler reinforcement—they can release ions from their inorganic compounds damaging oral pathogens, deliver calcium phosphate compounds, provide contrast during imaging, protect dental tissues during a bacterial acid attack, and improve the mineral content of the bonding interface. These capabilities make metal oxide nanoparticles and nanotubes useful for dental adhesives and composites, as these materials are the most used restorative materials in daily dental practice for tooth restorations. Secondary caries and material fractures have been recognized as the most common routes for the failure of composite restorations and bonding interface in the clinical setting. This review covers the significant capabilities of metal oxide nanoparticles and nanotubes incorporated into dental adhesives and composites, focusing on the novel benefits of antibacterial properties and how they relate to their translational applications in restorative dentistry. We pay close attention to how the development of contemporary antibacterial dental materials requires extensive interdisciplinary collaboration to accomplish particular and complex biological tasks to tackle secondary caries. We complement our discussion of dental adhesives and composites containing metal oxide nanoparticles and nanotubes with considerations needed for clinical application. We anticipate that readers will gain a complete picture of the expansive possibilities of using metal oxide nanoparticles and nanotubes to develop new dental materials and inspire further interdisciplinary development in this area.

Matrix Metalloproteinase 2 Is Associated With Secondary Caries Independent From the Restorative Material

Certain patients, despite receiving proper treatment, still show higher failure rates of restorative dental treatments. The aim of this work was to test if MMP2 and MMP3 alleles are overrepresented in individuals with secondary caries. A total of 1,089 individuals from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository project were selected for this study. From this total, 341 individuals were selected for having a record of secondary caries in any type of restoration and were matched with 748 individuals by sex, age, ethnicity, and restorative work in the same teeth that did not fail. Genomic DNA extracted from saliva was used to obtain genotypes in five markers of MMP2 and MMP3 using TaqMan chemistry and end-point analysis. Chi-square was used to test if differences in allele and genotype distributions were statistically different at an alpha of 0.05. The less common allele and homozygote genotype of MMP2 rs9923304 were less commonly found among individuals with secondary caries. The less common allele of MMP2 rs2287074 was also less frequent among individuals with secondary caries. These results provide statistical evidence for the role of MMP2 in failure of restorations due to secondary caries. We can conclude that MMP2 variation impacts the risk of having secondary caries, independent of the restorative material.

Glass Ionomer Versus Self-adhesive Cement and the Clinical Performance of Zirconia Coping/Press-on Porcelain Crowns

SUMMARY Objective: This split-mouth clinical study investigated the effect of luting cement on the performance of veneered yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) zirconia crowns. Methods and Materials: A total of 60 crowns prepared with Y-TZP coping and press-on porcelain were made with a split-mouth design in 30 participants. The crowns were cemented either with glass ionomer cement (GIC) (Meron, Voco) or with self-adhesive resin cement (Bifix-SE, Voco). The restorations were assessed immediately after treatment and after 6, 12, 24, 36, and 48 months using the modified United States Public Health Service criteria. The parameters analyzed were retention, color stability, marginal discoloration, marginal adaptation, surface roughness, anatomic form, and secondary caries. The differences between the groups were analyzed by the Fisher exact test in each period of evaluation. The survival rate was analyzed with the Kaplan–Meier and log-rank test (α=0.05). Results: After 48 months, 20 participants attended the recall. During the period of evaluation, 1 crown cemented with glass ionomer cement and 1 crown cemented with resin cement lost retention. Color match, marginal discoloration and adaptation, surface roughness, and anatomic form did not change in any of the periods evaluated, and no secondary caries was observed. No significant differences were found between the 2 luting cements for any of the clinical parameters analyzed, nor for the survival rates during the study. Conclusions: The type of cement did not influence the performance of the crowns after 48 months of clinical use. Both cements resulted in adequate retention rates, aesthetic and functional outcomes, and biological response.

Clinical Effectiveness of Pre-treatment with Chlorhexidine in Adhesive Dental Restorations. Systematic Review and Meta-analysis.

Objective: To determine, by means of a systematic review and meta-analysis, the clinical effectiveness of pre-treatment with chlorhexidine (CHX) in adhesive dental restorations. Material and Methods: A literature search was conducted until February 2020, in the biomedical databases: Pubmed, Embase, Scielo, Science Direct, Scopus, SIGLE, LILACS, Google Scholar and the Cochrane Central Registry of Clinical Trials. The selection criteria of the studies were defined, which were: randomized and controlled clinical trials, without language and time restrictions, and reporting the clinical effects (retention, marginal discoloration, marginal adaptation, postoperative sensitivity and secondary caries) of pre-CHX treatment in adhesive dental restorations. Study risk of bias was analyzed using the Cochrane Handbook of Systematic Reviews of Interventions. Results: The search strategy resulted in six articles of which five entered a meta-analysis. The studies reported that there was no difference in retention, marginal discoloration, marginal adaptation, postoperative sensitivity, and secondary caries from pre-treatment with CHX in adhesive dental restorations. Conclusion: The reviewed literature suggests that pretreatment with CHX does not influence the clinical effectiveness in adhesive dental restorations.

Recent Progress in Antimicrobial Strategies for Resin-Based Restoratives

Repairing tooth defects with dental resin composites is currently the most commonly used method due to their tooth-colored esthetics and photocuring properties. However, the higher than desirable failure rate and moderate service life are the biggest challenges the composites currently face. Secondary caries is one of the most common reasons leading to repair failure. Therefore, many attempts have been carried out on the development of a new generation of antimicrobial and therapeutic dental polymer composite materials to inhibit dental caries and prolong the lifespan of restorations. These new antimicrobial materials can inhibit the formation of biofilms, reduce acid production from bacteria and the occurrence of secondary caries. These results are encouraging and open the doors to future clinical studies on the therapeutic value of antimicrobial dental resin-based restoratives. However, antimicrobial resins still face challenges such as biocompatibility, drug resistance and uncontrolled release of antimicrobial agents. In the future, we should focus on the development of more efficient, durable and smart antimicrobial dental resins. This article focuses on the most recent 5 years of research, reviews the current antimicrobial strategies of composite resins, and introduces representative antimicrobial agents and their antimicrobial mechanisms.

In Vitro Antibacterial Effect of Fifth Generation Dentin Bonding Agent Incorporated With Nisin on Streptococcus Mutans

Introduction Secondary caries is the most common cause of failure of composite restorations. This study evaluated the antibacterial efficacy of fifth generation bonding agent (BA) modified with Nisin, a polypeptide bacteriocin against Streptococcus mutans based on its growth, adherence and membrane integrity. Methods Adhesive eluents of the three experimental bonding agents, namely control BA only, bonding agent with 1 wt% Nisin (NBA 1) and 5 wt% Nisin (NBA 5) were obtained using 250 μl Brain Heart Infusion (BHI) broth. To this, 10 μl S. mutans culture was added and incubated at 37°C. Bacterial growth was estimated by changes in optical density using spectrophotometry every 20 min for 2 hours. The results were statistically analysed using one way ANOVA followed by Post Hoc test. For adherence and membrane integrity test, 10μl of BHI supplemented with 1% sucrose and 50 μl of bacterial suspension were inoculated onto the cured specimens, and incubated for 4 hours. After rinsing, 1ml of Live/Dead BacLight bacterial viability stain was added and incubated in the dark for 15 min and observed under CLSM for intact (green/live) and damaged (red/dead) bacterial membranes. Results Mean optical density was significantly higher in control group at all time intervals, with experimental groups showing concentration dependant reduction in bacterial growth. Correspondingly, the experimental groups showed higher amount of dead than live bacteria, while live bacteria were predominant in the control group. Significance Addition of an antibacterial agent Nisin in bonding agent may render the resin dentin interface more resistant to bacterial penetration, thus reducing the incidence of secondary caries.