Incidence of endodontic therapy after complete or partial coverage glass-ceramic restorations with a follow-up time of over 30 years: A prospective clinical study.

Statement Of Problem: Long-term clinical data are lacking on the comparison of the incidence of endodontic therapy in adhesively luted complete and partial coverage glass-ceramic restorations, as well as on the effect of technique and clinical variables.

Purpose: The purpose of this prospective clinical study was to assess the long-term incidence of teeth requiring endodontic therapy after receiving either complete or partial coverage glass-ceramic restorations.

Material And Methods: Participants requiring single anterior complete, posterior complete, or posterior partial (inlay or onlay) coverage restoration, or a combination of these on a vital tooth were recruited from a clinical private practice.

Securing Public Trust: Dentistry, SARS-CoV-2, and "Testing for Tomorrow".

The SARS-CoV-2 pandemic created societal upheaval well beyond what anyone, but the oldest of Americans, has seen in their lifetime. As the pandemic begins to subside, it is leaving behind a legacy of permanently changed practices, including enhanced environmental controls in clinical settings, reconsideration of modes of personal protective equipment outsourcing, changes and/or reinterpretation of dental practice acts, and entirely new approaches to testing and vaccine design, among many others. This article focuses on one change that the authors hope will prevail: greater trust in the dental profession as a valuable public resource during healthcare crises.

10.9-year survival of pressed acid etched monolithic e.max lithium disilicate glass-ceramic partial coverage restorations: Performance and outcomes as a function of tooth position, age, sex, and the type of partial coverage restoration (inlay or onlay).

Statement Of Problem: Long-term clinical data on the survival of pressed lithium disilicate glass-ceramic when used with partial coverage restorations and the effect that different technical and clinical variables have on survival are sparse.

Purpose: The purpose of this clinical study was to determine the 10.9-year survival of pressed lithium disilicate glass-ceramic partial coverage restorations and associated clinical parameters on outcomes.

Comparison of 16.9-year survival of pressed acid etched e.max lithium disilicate glass-ceramic complete and partial coverage restorations in posterior teeth: Performance and outcomes as a function of tooth position, age, sex, and thickness of ceramic material.

Statement Of Problem: Long-term clinical data are lacking on the comparison of the survival of adhesively luted pressed e.max lithium disilicate glass-ceramic complete and partial coverage restorations in posterior dentitions and the effect that different technical and clinical variables have on their survival.

Purpose: The purpose of this clinical study was to examine and compare the 16.

Digital dentistry: The new state of the art - Is it disruptive or destructive?

Objective: Summarizing the new state of the art of digital dentistry, opens exploration of the type and extent of innovations and technological advances that have impacted - and improved - dentistry. The objective is to describe advances and innovations, the breadth of their impact, disruptions and advantages they produce, and opportunities created for material scientists.

Methods: On-line data bases, web searches, and discussions with industry experts, clinicians, and dental researchers informed the content.

Ten-year survival of pressed, acid-etched e.max lithium disilicate monolithic and bilayered complete-coverage restorations: Performance and outcomes as a function of tooth position and age.

Statement Of Problem: Long-term clinical data on the survival of pressed lithium disilicate glass-ceramic restorations and the effect that different technical and clinical variables have on survival are lacking.

Purpose: The purpose of this clinical study was to examine the 10-year survival of pressed lithium disilicate glass-ceramic restorations and the relationship between clinical parameters on outcomes.

Material And Methods: Five hundred and fifty-six patients, ranging in age from 17 to 97 years, from a private clinical practice were enrolled.

Conventional and modified veneered zirconia vs. metalloceramic: fatigue and finite element analysis.

Purpose: The purpose of this study was to test the hypothesis that all-ceramic crown core-veneer system reliability is improved by modifying the core design and as a result is comparable in reliability to metal-ceramic retainers (MCR). Finite element analysis (FEA) was performed to verify maximum principal stress distribution in the systems.

Materials And Methods: A first lower molar full crown preparation was modeled by reducing the height of proximal walls by 1.

Failure modes of Y-TZP crowns at different cusp inclines.

Objectives: To compare the reliability of the disto-facial (DF) and mesio-lingual (ML) cusps of an anatomically correct zirconia (Y-TZP) crown system. The research hypotheses tested were: (1) fatigue reliability and failure mode are similar for the ML and DF cusps; (2) failure mode of one cusp does not affect the failure of the other.

Methods: The average dimensions of a mandibular first molar crown were imported into CAD software; a tooth preparation was modelled by 1.

Bond strength to high-crystalline content zirconia after different surface treatments.

The aim of this study was to evaluate the effect of primers, luting systems and aging on bond strength to zirconium oxide substrates. Eighteen zirconia discs (19.5 x 4 mm) were polished and treated (n = 3) either with a MDP primer (Md) or with a MDP and VBATDT primer (MV).

Design features of a three-dimensional molar crown and related maximum principal stress. A finite element model study.

Objective: To evaluate the effects of clinically relevant variables on the maximum principal stress (MPS) in the veneer layer of an anatomically correct veneer-core-cement-tooth model.

Methods: The average dimensions of a mandibular first molar crown were imported into CAD software; a tooth preparation was modeled by reducing the proximal walls by 1.5 mm and the occlusal surface by 2.

A novel approach to multihazard modeling and simulation.

Objective: To develop and apply a novel modeling approach to support medical and public health disaster planning and response using a sarin release scenario in a metropolitan environment.

Methods: An agent-based disaster simulation model was developed incorporating the principles of dose response, surge response, and psychosocial characteristics superimposed on topographically accurate geographic information system architecture. The modeling scenarios involved passive and active releases of sarin in multiple transportation hubs in a metropolitan city.

Effect of proximal wall height on all-ceramic crown core stress distribution: a finite element analysis study.

Purpose: Mechanical analyses of idealized crown-cement-tooth systems through finite element analysis (FEA) has provided valuable insight concerning design parameters and materials that favor lower stress patterns. However, little information regarding variation of basic preparation guidelines in stress distribution has been available. The primary objective of this study was to evaluate maximum principal stresses on a molar crown veneer plus core system natural tooth configuration preparation with variations in the ratio of proximal axial length (PAL) to buccal axial length (BAL) as well as loading condition and position.

Fracture Modes in Curved Brittle Layers Subject to Concentrated Cyclic Loading in Liquid Environments.

Damage response of brittle curved structures subject to cyclic Hertzian indentation was investigated. Specimens were fabricated by bisecting cylindrical quartz glass hollow tubes. The resulting hemi-cylindrical glass shells were bonded internally and at the edges to polymeric supporting structures and loaded axially in water on the outer circumference with a spherical tungsten carbide indenter.

Effects of geometry on fracture initiation and propagation in all-ceramic crowns.

The complex and patient-unique geometry of posterior all-ceramic dental crowns represents a particularly interesting set of challenges to understanding stress concentration and fracture evolution in response to loading. A series of numerical and physical experiments, with both single cycle and fatigue loading, show that geometry profoundly influences the stress concentration and fracture initiation and propagation. In stylized crowns with uniform axial wall height, stresses concentrate beneath the indenter.

Competition of fracture mechanisms in monolithic dental ceramics: flat model systems.

Monolithic (single layer) glass-ceramic restorations often fail from chipping and fracture. Using blunt indentation of a model flat porcelain-like brittle layer bonded onto a dentin-like polymer support system, a variety of fatigue fracture modes has been identified and analyzed: outer cone, inner cone, and median cracks developing in the near-contact region at the occlusal surface; radial cracks developing at the internal cementation surface along the loading axis. Our findings indicate that monolithic glass-ceramic layers are vulnerable to both occlusal surface damage and cementation internal surface fracture.

All hazards training: incorporating a catastrophe preparedness mindset into the dental school curriculum and professional practice.

Catastrophic preparedness should be incorporated into the dental school curriculum. The experience at New York University College of Dentistry is that a combination of catastrophic preparedness elements integrated within existing courses with a short, meaningful capstone course dedicated to all hazards preparedness can be accomplished successfully and meet proposed competencies for training in the dental curriculum. The roles and responsibilities in catastrophic response preparedness and response of dentists are actively being discussed by the dental profession.

MicroCT analysis of hydroxyapatite bone repair scaffolds created via three-dimensional printing for evaluating the effects of scaffold architecture on bone ingrowth.

Recent studies have shown that it is now possible to construct tissue-engineered bone repair scaffolds with tight pore size distributions and controlled geometries using 3-D Printing techniques (3DP). This study evaluated two hydroxyapatite (HA) 8-mm diameter discs with controlled architectures in a rabbit trephine defect at 8 and 16 weeks using a 2 x 2 factorial design. Input parameters were time and scaffold void volume at two levels.

Can material properties predict survival of all-ceramic posterior crowns?

Increasingly strong all-ceramic materials have been introduced often with great fanfare and promise for long-term clinical performance. However, especially on posterior teeth, performance has been less than anticipated. This article reviews failure rates and modes of all-ceramic crowns and addresses the question of whether material properties can accurately predict clinical survival.

In vivo bone response to 3D periodic hydroxyapatite scaffolds assembled by direct ink writing.

The in vivo bone response of 3D periodic hydroxyapatite (HA) scaffolds is investigated. Two groups of HA scaffolds (11 mm diameter x 3.5 mm thick) are fabricated by direct-write assembly of a concentrated HA ink.

Damage accumulation and fatigue life of particle-abraded ceramics.

Purpose: This investigation compared initial and fatigue strengths of particle-abraded ceramics to those of as-polished alumina and zirconia ceramics in crown-like layer structures.

Materials And Methods: Alumina or zirconia plates bonded to polycarbonate substrates were subjected to single-cycle and multi-cycle contact (fatigue) loading. Cementation surfaces of the ceramic were damaged by controlled particle abrasion, indentation with a sharp diamond at low load, or a blunt indenter at high load.

Engineering long term clinical success of advanced ceramic prostheses.

Biocompatability and, in some applications, esthetics make all-ceramic prostheses compelling choices but despite significant improvements in materials properties and toughening mechanisms, these still have significant failure rates. Factors that contribute to the degradation in strength and survival include material selection and prosthesis design which set the upper limit for performance. However, fabrication operations introduce damage that can be exacerbated by environmental conditions and clinical function.

Computer-aided design and fabrication of dental restorations: current systems and future possibilities.

Background: For more than 20 years, researchers have been trying to automate conventional manual processes in dental technology with the hope of producing higher- and more uniform-quality materials, standardizing manufacturing processes and reducing production costs.

Methods: The authors review existing computer-aided design (CAD)/computer-aided manufacturing (CAM) systems, describing the components of CAD/CAM technologies and addressing the limitations of current systems, and suggest possibilities for future systems.

Conclusions: Existing dental CAD/CAM systems vary dramatically in their capabilities; each has distinct advantages and limitations.

Proposed educational objectives for hospital-based dentists during catastrophic events and disaster response.

The purpose of this project was to define education and training requirements for hospital-based dentists to efficiently and meaningfully participate in a hospital disaster response. Eight dental faculty with hospital-based training and/or military command and CBRNE (chemical, biological, radiological, nuclear, and explosive) expertise were recruited as an expert panel. A consensus set of recommended educational objectives for hospital-based dentists was established using the following process: 1) identify assumptions supported by all expert panelists, 2) determine current advanced dental educational training requirements, and 3) conduct additional training and literature review by various panelists and discussions with other content and systems experts.