Guidance for evaluating biomaterials' properties and biological potential for dental pulp tissue engineering and regeneration research.

Background: Dental pulp regeneration is a complex and advancing field that requires biomaterials capable of supporting the pulp's diverse functions, including immune defense, sensory perception, vascularization, and reparative dentinogenesis. Regeneration involves orchestrating the formation of soft connective tissues, neurons, blood vessels, and mineralized structures, necessitating materials with tailored biological and mechanical properties. Numerous biomaterials have entered clinical practice, while others are being developed for tissue engineering applications.

A Historical Perspective on Dental Composite Restorative Materials.

This review article will discuss the origin of resin-based dental composite materials and their adoption as potentially useful adjuncts to the primary material used by most dentists for direct restorations. The evolution of the materials, largely driven by the industry's response to the needs of dentists, has produced materials that are esthetic, strong, and versatile enough to be used in most areas of the oral cavity to replace or restore missing tooth structures. Significant advancements, such as the transition from chemical to light-curing materials, refinements in reinforcing particles to produce optimum polishing and wear resistance, formulating pastes with altered viscosities to create highly flowable and highly stiff materials, and creating materials with enhanced depth of cure to facilitate placement, will be highlighted.

Isolated effect of filler particle size on surface properties of experimental resin composites before and after toothbrush abrasion.

Objective: This study aimed to isolate the relationship between filler size and the surface properties of roughness and gloss before and after toothbrush abrasion for experimental resin-based composites (RBCs) containing uniform spherical fillers.

Materials And Methods: Five experimental light-cured RBCs with different spherical filler sizes and three commercial RBCs were studied. Forty specimens were polished using silicon carbide papers.

Thiol Quantification Using Colorimetric Thiol-Disulfide Exchange in Nonaqueous Solvents.

A careful analysis of two (thiol-disulfide exchange) thiol quantification chromophores' behavior (Ellman's reagent and Aldrithiol-4) in nonaqueous solvents is presented. A wide range of kinetic profiles and response factors were measured to exhibit a large variance for nonaqueous systems. We report several robust benchtop and room-temperature methods using different organic solvents compared to aqueous conditions.

Lessons learned from the Cracked Tooth Registry: A 3-year clinical study in the Nation's Network.

Background: This article reviews the most salient lessons learned from a large, multisite, 3-year observational study of posterior teeth with cracks conducted by The National Dental Practice-Based Research Network.

Types Of Studies Reviewed: Eight articles published over a 6-year period (2017-2022) describing clinical characteristics of posterior teeth with cracks and their treatment and outcomes are reviewed and discussed to answer 3 common questions faced by oral health care clinicians: Which cracked teeth will get worse? When should practitioners intervene? What is the best treatment?

Results: Although cracks in teeth are prevalent, few will fracture (3%) or show crack progression in 3 years (12%). Characteristics that guide the clinician to treatment include active caries, biting pain, and to a lesser degree, having a crack detectable with an explorer, connecting with a restoration, or blocking transilluminated light; the main treatment chosen is a complete crown.

"Fatigue-Crack Propagation Behavior in Microcapsule-Containing Self-Healing Polymeric Networks".

Over the last years, research on the design of dental self-healing polymers has grown dramatically. It is related to the promising potential of maximizing the clinical lifespan of dental restorations that this strategy holds. In this manuscript, the microcapsule-based strategy is innovated by incorporating the high toughness component N,-Dimethylacrylamide (DMAM) into the healing agent systems and analyzing in-depth the change in crack propagation behavior induced by the addition of microcapsules into the highly crosslinked polymeric network.

Effect of thickness on the degree of conversion of two bulk-fill and one conventional posterior resin-based composites at high irradiance and high temporal resolution.

Objectives: This study: 1) measures the effect of sample thickness and high irradiance on the depth-dependent time delay before photopolymerization reaction onset; 2) determines if exposure reciprocity exists; 3) measures the conversion rate at four irradiance levels; 4) determines the time, t, at which the maximum DC rate is reached for two bulk-fill and one conventional posterior resin-based composites (RBCs).

Methods: Tetric PowerFill IVA shade (Ivoclar Vivadent) and Aura bulk-fill ultra universal restorative (SDI), and one conventional posterior resin-based composite (RBC), Heliomolar A3 (Ivoclar Vivadent), that were either 0.2 mm, 2 mm, or 4 mm thick were photocured using a modified Bluephase G4 (Ivoclar Vivadent) light-curing unit (LCU) that delivered a single emission band (wavelength centered at 449 nm).

Effect of ethyl cellulose coating as an evaluation agent against contamination on the bond strength of zirconia restorations: An in vitro study.

Statement Of Problem: During the trial placement of zirconia restorations, contamination of the bonding surface is inevitable. Although cleaning methods for contaminated surfaces have been described, a method of preventing saliva contamination of the bonding surface of zirconia restorations is lacking.

Purpose: The purpose of this in vitro study was to investigate an ethyl cellulose coating as an evaluation agent to mitigate the effects of saliva contamination on the bond strength of zirconia restorations.

Onset and resolution of pain among treated and untreated posterior teeth with a visible crack: Three-year findings from the national dental practice-based research network.

Objective: Cracked teeth may be associated with pain, especially biting pain, and to a lesser degree cold and spontaneous pain.  Described are how commonly these pains remain constant, develop, or resolve over time, none of which have been well-described, especially among untreated cracked teeth.

Methods: Cracked teeth from the Cracked Tooth Registry (CTR) study were followed for 3 years.

Development and maintenance of surface gloss of dental composites after polishing and brushing: Review of the literature.

Objective: To describe the effect of the composites' composition to produce high surface smoothness/gloss using finishers/polishers, and to assess maintained smoothness/gloss under toothbrush abrasion.

Materials And Methods: PubMed papers published from January 01, 2000 to September 01, 2021 were included, and keywords used were: filler particle size, shape, amount of dental composites; finishing/polishing, gloss/roughness, and toothbrush abrasion of composites. Seventy-five in-vitro studies were included in this literature review.

Effect of Novel Bioactive Glass-Containing Dentin Adhesive on the Permeability of Demineralized Dentin.

This study aimed to evaluate the effect of a novel bioactive glass (BAG)-containing dentin adhesive on the permeability of demineralized dentin. Bioactive glass (85% SiO, 15% CaO) was fabricated using the sol-gel process, and two experimental dentin adhesives were prepared with 3 wt% silica (silica-containing dentin adhesive; SCA) or BAG (BAG-containing dentin adhesive; BCA). Micro-tensile bond strength (μTBS) test, fracture mode analysis, field-emission scanning electron microscopy (FE-SEM) analysis of adhesive and demineralized dentin, real-time dentinal fluid flow (DFF) rate measurement, and Raman confocal microscopy were performed to compare SCA and BCA.

Changes of residual stresses on the surface of leucite-reinforced ceramic restoration luted with resin composite cements during aging in water.

The objective of this study was to compare the changes in the residual stresses present on the surface of leucite-reinforced dental ceramic restorations luted with a self-adhesive and a conventional resin composite cement during aging in water. Ring specimens made of a leucite-reinforced ceramics were luted to ceramic cylinders using a self-adhesive (Panavia SA Luting Plus) or a conventional resin composite cement (Panavia V5) in dual-cure or self-cure mode. Residual stresses on the ring surface were measured using indentation fracture method at 1 h, 1, 3, 7, 14 and 28 days of the 37 °C water immersion.

Clinical Performance of CAD/CAM Monolithic Lithium Disilicate Implant-Supported Single Crowns Using Solid or Predrilled Blocks in a Fully Digital Workflow: A Retrospective Cohort Study With Up To 33 Months of Follow Up.

Purpose: To assess the clinical performance of CAD/CAM monolithic implant-supported restorations manufactured using a fully digital workflow and two different types of ceramic blocks.

Materials And Methods: One hundred and one patients received single-unit implant-supported restorations at a University predoctoral clinic. All restorations were designed and fabricated using either a predrilled LS block (group P, n = 59) or a conventional solid LS block with an occlusal opening drilled manually prior to crystallization (group M, n = 42).

Toughening and polymerization stress control in composites using thiourethane-treated fillers.

Filler particle functionalization with thiourethane oligomers has been shown to increase fracture toughness and decrease polymerization stress in dental composites, though the mechanism is poorly understood. The aim of this study was to systematically characterize the effect of the type of filler surface functionalization on the physicochemical properties of experimental resin composites containing fillers of different size and volume fraction. Barium glass fillers (1, 3 and 10 µm) were functionalized with 2 wt% thiourethane-silane (TU-Sil) synthesized de novo and characterized by thermogravimetric analysis.

Effect of side-group methylation on the performance of methacrylamides and methacrylates for dentin hybridization.

Unlabelled: The stability of the bond between polymeric adhesives to mineralized substrates is crucial in many biomedical applications. The objective of this study was to determine the effect of methyl substitution at the α- and β-carbons on the kinetics of polymerization, monomer hydrolytic stability, and long-term bond strength to dentin for methacrylamide- and methacrylate-based crosslinked networks for dental adhesive applications.

Methods: Secondary methacrylamides (α-CH substituted=1-methyl HEMAM, β-CH substituted=2-methyl HEMAM, and unsubstituted=HEMAM) and OH-terminated methacrylates (α- and β-CH mixture=1-methyl HEMA and 2-methyl HEMA, and unsubstituted=HEMA) were copolymerized with urethane dimethacrylate.

Fractography of clinical failures of indirect resin composite endocrown and overlay restorations.

Objectives: Compare failure modes and fracture origins using fractography on recovered clinically fractured parts of indirect resin composite endocrowns and overlay restorations on endodontically treated teeth (ETT).

Methods: Four endocrowns (3 molars, 1 premolar) and one overlay (molar) adhesively luted on ETT were recovered after fracturing during function. The time in service ranged between 4 and 48 months.

Visually acceptable gloss threshold for resin composite and polishing systems.

Background: The objective of this study was to compare dentists' perceptions of gloss values of composite specimens with increased levels and to identify the gloss value considered to be clinically acceptable.

Methods: Disk-shaped composite specimens were finished and polished 3 ways: metallurgically using silicon carbide papers and alumina paste, manually using Enhance finisher and PoGo polisher (EP) (Dentsply Sirona), and manually using Sof-Lex (SLex) disks (3M). Specimens were produced with surface gloss ranging from 0 through 100 gloss units (GU) in increments of approximately 10 GU as measured with a glossmeter.

Incorporation of Apigenin and tt-Farnesol into dental composites to modulate the Streptococcus mutans virulence.

Objectives: The aim of this in vitro study was to incorporate two anti-caries agents, Apigenin and tt-Farnesol, to resin composite and resin cement to reduce the virulence of Streptococcus mutans around dental restorations.

Methods: Apigenin (Api, 5 mM) and tt-Farnesol (Far, 5 mM) were added alone, together, and combined with fluoride (F). Biofilm of S.

Baseline characteristics as 3-year predictors of tooth fracture and crack progression: Findings from The National Dental Practice-Based Research Network.

Background: The authors of this practice-based study estimated the risk of experiencing tooth fractures and crack progression over 3 years and correlated baseline patient-, tooth-, and crack-level characteristics with these outcomes.

Methods: Two-hundred-and-nine National Dental Practice-Based Research Network dentists enrolled a convenience sample of 2,601 participants with a cracked vital posterior tooth that had been examined for at least 1 recall visit over 3 years. Data were collected at the patient, tooth, and crack levels at baseline, annual follow-up visits, and any interim visits.

Probing the hierarchy of evidence to identify the best strategy for placing class II dental composite restorations using current materials.

Objective: The objective of this review is to present a synopsis of the existing clinical and in vitro evidence regarding placement of direct class II restorations with dental composites of varying viscosities, focusing on the marginal integrity achievable.

Overview: The literature on class II composites placed with various techniques was searched through PubMed, Scopus, and the citations of identified articles, focusing on aspects related to adaptation and clinical performance. Studies comparing layering of conventional composite to layering with a flowable liner, including the "snow plow technique," use of warmed composite, flowable bulk-fill liners with a conventional composite capping layer, and bulk-fill restorative in a single or incremental fill (including placement with sonic energy and dual-curing) CONCLUSIONS: In vitro and clinical evidence does not support any one specific method or material type for achieving optimal performance when restoring class II cavity preparations with current dental composites.