Effects of clinical experience and explorer type on judged crown margin acceptability.

Purpose: This study was undertaken to simultaneously compare instrumentation type and operator characteristics in judgments of clinical acceptability of crowns exhibiting a controlled range of marginal gaps. The research was conducted in a laboratory setting and generalizability analysis was used as a statistical technique to identify the sources contributing to variation in the judgment outcome.

Materials And Methods: A crown was seated on an ivorine tooth in a device that permitted continuous adjustment in intervals of 25 mum to produce known marginal gaps ranging from zero to 250 microm.

A general method for describing sources of variance in clinical trials, especially operator variance, in order to improve transfer of research knowledge to practice.

Purpose: The purpose of this study was to demonstrate how the skill level of the operator and the clinical challenge provided by the patient affect the outcomes of clinical research in ways that may have hidden influences on the applicability of that research to practice. Rigorous research designs that control or eliminate operator or patient factors as sources of variance achieve improved statistical significance for study hypotheses. These procedures, however, mask sources of variance that influence the applicability of the conclusions.

Fabrication of a caliper device for interalveolar dimension measurement in the complete denture patient.

A method is presented for measuring interalveolar dimension (IAD) of existing dentures using a caliper. Directions for construction of an IAD gauge are included. This device is easy to construct and "zeroes out" in the closed position.

Dimensional accuracy of 7 die materials.

Purpose: The purpose of this study was to compare the linear dimensional accuracy and the handling characteristics of 7 die materials.

Materials And Methods: A master die analogous to a complete veneer crown preparation was machined from medical grade stainless steel, and 3 measurements (1: vertical; 2 and 3: horizontal) were made from 3 scribed reference lines. Individual polyvinylsiloxane impressions were made (n = 10) for each of the specimens.

Simplified clinical procedure for fitting and removing inlays/onlays prior to cementation.

This article describes a procedure in which polytetrafluoroethylene (PTFE) tape is used as a liner for fitting intracoronally retained, indirect restorations. The minimal thickness of the tape allows complete seating and confirmation of marginal fit of restorations during try-in, yet the tape is tough enough to permit trouble-free removal of the restoration afterward. Protection against inadvertent loss of the restoration can be gained if a knot is placed close to the occlusal surface of the restoration prior to its removal.