Effectiveness of digital impressions in a predoctoral clinical curriculum.

Aim: The purpose of the present study was to investigate the effectiveness of digital impressions made by 3rd and 4th year dental students using a retrospective record review at one USA dental school during a 1-year period.

Materials And Methods: After reviewing patient records related to quality assurance, 125 digital impressions and the produced restorations were evaluated. Effectiveness and acceptability of digital impressions and restorations were associated with students' educational level, number of prepared teeth scanned, type of produced restoration, and restorative material used.

A survey of US dental schools on predoctoral implant curricula with emphasis on diagnosing and treating implant complications.

Statement Of Problem: Implant complications have been reported to occur at high rates and frequencies. Whether these high rates are observed in predoctoral implant programs and whether future dentists are educated to diagnose and treat implant complications is unknown.

Purpose: The purpose of this study was to analyze and report the results of a survey on US predoctoral curricula related to implant treatment and with an emphasis on diagnosing and treating implant complications.

Should Pass/Fail Grading Be Used Instead of Traditional Letter Grades in Dental Education? Two Viewpoints: Viewpoint 1: Pass/Fail Grading Improves Learning Experiences for Students and Viewpoint 2: Traditional Letter Grading Provides Objective Evaluation for Dental Education.

Discussions about which grading system (letter grade or pass/fail) is more effective in dental education have been occurring for several decades. As more institutions continue to consider the change from the traditional five-tier letter grading system (A/B/C/D/F) to a two-tier grading system (pass/fail), this debate will likely continue. This point/counterpoint article examines arguments for and against each type of grading system, taking into consideration academic performance, learning outcomes, psychological well-being, learning environment, acceptance/performance in postgraduate educational programs, and student motivation.

A preliminary three-dimensional finite element analysis of mandibular implant overdentures.

A treatment protocol that may lead to reduced mandibular posterior residual ridge resorption in patients with overdentures retained and supported by two interforaminal implants was investigated. The treatment included the addition of short implants in the posterior edentulous mandible for the presumed purpose of favorable provision of mechanical load stimulus to alveolar bone. Three-dimensional finite element analysis was used to model cited effective strains that may stimulate bone remodeling in two selected models.

Correlation of impression removal force with elastomeric impression material rigidity and hardness.

Purpose: Difficult impression removal has been linked to high rigidity and hardness of elastomeric impression materials. In response to this concern, manufacturers have reformulated their materials to reduce rigidity and hardness to decrease removal difficulty; however, the relationship between impression removal and rigidity or hardness has not been evaluated. The purpose of this study was to determine if there is a positive correlation between impression removal difficulty and rigidity or hardness of current elastomeric impression materials.

Effect of airborne-particle abrasion and aqueous storage on flexural properties of fiber-reinforced dowels.

Purpose: A great range of clinical failures have been observed with fiber-reinforced dowels, often attributed to fracture or bending of the dowels. This study investigated flexural properties of fiber-reinforced dowels, with and without airborne-particle abrasion, after storage in aqueous environments over time. Scanning electron microscopy (SEM) was used to analyze the mode of failure of dowels.

Probabilistic analysis of peri-implant strain predictions as influenced by uncertainties in bone properties and occlusal forces.

Objectives: The purpose of this study was to examine the influence of variability in bone properties and loading on peri-implant crestal and cancellous bone strains using a probabilistic approach, in combination with finite element (FE) analysis.

Material And Methods: Oblique occlusal loading was applied to a single endosseous implant embedded in a two-dimensional (2-D) FE model of a premolar section of a mandible. Perfect bonding was assumed at all interfaces.

Surface quality and long-term dimensional stability of current elastomeric impression materials after disinfection.

Purpose: The objectives of this investigation were to evaluate the effect of disinfection on surface quality and dimensional stability of more recent, reformulated vinylpolysiloxane (VPS) and polyether (PE) materials.

Methods: Using ANSI/American Dental Association (ADA) specification 19 protocols, 50 impressions of stainless steel dies were made with each material. Ten impressions of each material were randomly assigned to a treatment group: (1) no disinfectant; (2) 10-minute dual phenol immersion; (3) 1-hour dual phenol; (4) 10-minute sodium hypochlorite (NaOCl); and (5) 1-hour NaOCl.

Educational necessities to compensate for faculty shortage.

The purpose of this investigation was to evaluate whether senior dental students (4DS) could serve as effective instructors in a two-semester preclinical laboratory course and whether such teaching experience could enhance their interest in academics as a future career. Based on academic performance, five senior students were recruited to serve as instructors in a two-semester morphology/occlusion laboratory course in which ninety-five first-year dental students were enrolled. The first-year students were randomly assigned so that each student was instructed by a faculty member in one semester and a 4DS in the other semester.

Marginal adaptation of Cerec 3 CAD/CAM composite crowns using two different finish line preparation designs.

Purpose: The purpose of this study was to compare marginal discrepancies of Cerec 3 CAD/CAM composite crowns, fabricated on human prepared teeth with two different finish line designs, chamfer and shoulder.

Materials And Methods: Sixteen human molar teeth were used to prepare full crowns. Eight teeth were prepared with a 1-mm-wide chamfer finish line and the other eight with a 1.

A survey of U.S. prosthodontists and dental schools on the current materials and methods for final impressions for complete denture prosthodontics.

Purpose: The purpose of this study was to survey members of The American College of Prosthodontists (ACP) to evaluate current materials and methods for final impressions for complete denture prosthodontics in the United States. In addition, those methods were compared with methods and materials taught in U.S.

Moisture effect on polyether and polyvinylsiloxane dimensional accuracy and detail reproduction.

Purpose: This investigation evaluated and compared the dimensional accuracy and surface detail reproduction of two hydrophilic polyvinylsiloxane (PVS) and two polyether (PE) impression materials when used under dry and moist conditions.

Methods: Impressions were made of stainless steel dies as described in ANSI/ADA specification no. 19, with two vertical and three horizontal lines inscribed on the die superior surface.

Utilization of evidence-based informational resources for clinical decisions related to posterior composite restorations.

The purpose of this study was to characterize evidence-based informational resources utilization patterns of a sample of general dentists with respect to clinical decisions regarding posterior composite restorations. A stratified random sample of general practitioners belonging to the Academy of General Dentistry (n = 2880) was mailed a questionnaire that elicited information about practice characteristics and informational resources used for clinical decision making related to posterior composite restorations. Six hundred ninety-nine dentists responded (24 percent response rate).

Comparative evaluation of implant designs: influence of diameter, length, and taper on strains in the alveolar crest. A three-dimensional finite-element analysis.

Objectives: Our aim was to analyze and compare systematically the relative and interactive effects of implant diameter, length, and taper on calculated crestal bone strains.

Material And Methods: Three-dimensional finite-element models were created of a 20-mm premolar section of the mandible with a single endosseous implant embedded in high- or low-density cancellous bone. Oblique (200-N vertical and 40-N horizontal) occlusal loading was applied.

Effect of measurement site on the dimensional accuracy of die-forming materials and techniques.

To date, the comparisons of dimensional accuracy of various die materials has been investigated primarily by using a one-dimensional measurement on one die. However, a single measurement may not adequately represent the complex preparations that are encountered frequently in clinical dentistry. This investigation utilized a standardized model with two identical dies to measure die accuracy at four sites, using five different die-forming materials/techniques.

Dimensional accuracy and surface detail reproduction of two hydrophilic vinyl polysiloxane impression materials tested under dry, moist, and wet conditions.

Statement Of Problem: A major limitation of vinyl polysiloxane (VPS) impression materials is their hydrophobicity. There are 2 aspects to this problem, the wettability of the polymerized impression by dental gypsum materials and the ability of the unpolymerized material to wet intraoral tissues. To address this problem, manufacturers have added surfactants and labeled the new products as hydrophilic vinyl polysiloxane.

Comparison of recordings obtained with computerized axiography and mechanical pantography at 2 time intervals.

Purpose: The purpose of this study was to compare recordings of mandibular movements obtained with a Denar mechanical pantograph to those obtained with a Denar computerized axiograph (Cadiax compact).

Materials And Methods: Pantographic recordings and computerized axiograms were collected on 10 subjects. All of the subjects had intact dentition and no clinical signs or symptoms of temporomandibular dysfunction.