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Biomedical subjects

W F Malone

Publications and source records attributed to W F Malone.

At least 55 records · Page 3Linked to original sources
PubMed1984

Clinical evaluation of the accuracy of interocclusal recording materials.

The importance of accurate, reliable recording mediums cannot be understated. Function and esthetics are directly related to this critical step. Dental recording materials must be accurate, easily manipulated, and economical for effective use. Five types of intraoral records of 31 patients were registered and placed on an arcon, semiadjustable articulator to measure the magnitude and direction of distortion. The results were the following. Polyether interocclusal recording medium without a carrier was the most accurate. Polyether and zinc oxide-eugenol pastes with carriers were the next most accurate recording mediums, but they required a disciplined technique. Recording waxes were consistently unreliable. Distortion occurred more frequently in a vertical direction, followed by an anteroposterior direction.

Clinical Trials as Topic↗
PubMed1982

Crown contours and gingival response.

The following periodontal/restorative interrelations should be observed: 1. Deflective contours and/or overcontouring should be avoided in the cervical third and the interproximal surfaces of tooth restorations. 2. Overcontouring of the interproximal region is common and harmful to periodontal health. 3. Adequate tooth reduction at the gingival margin and interproximally provides for restorative materials and lessens the potential for overcontouring in these critical regions. 4. Fluting or barreling of exposed furcations eliminates plaque shelves and promotes accessibility for hygiene. 5. Minimal disruption within the intracrevicular space during tooth preparation allows a more predictable, favorable periodontal response to satisfactorily contoured restorations.

Crowns↗
PubMed1981

Comparison of elastomeric impression materials used in fixed prosthodontics.

Five elastomeric impression materials were evaluated: two polysulfides (one lead-cure and one non-lead cure), two silicones (one condensation polymerization and one addition polymerization), and one polyether. These materials were subjected to simulated clinical conditions. Two techniques were evaluated. All materials were evaluated initially with use of a custom tray and manufacturers' adhesive. A second evaluation was performed without using the tray system. Both techniques were subjected to statistical comparison. Conclusions of the research were as follows: 1. All impression materials that were poured immediately and evaluated using a custom tray and adhesive consistently demonstrated superior results in comparison to those tested without the custom tray. 2. Polyether material consistently yielded superior results with or without a custom tray when compared to the other impression materials. The additional polymerization silicone ranked second, followed by the lead-cure polysulfide and the condensation polymerization silicone, respectively.

Dental Impression Materials↗
PubMed1981

Accuracy and dimensional stability of four interocclusal recording materials.

Four materials, zinc oxide-eugenol paste, eugenol-free-zinc oxide paste, a silicone, and polyether jaw relations registration material were studied in a controlled laboratory environment to determine their accuracy and stability in intervals over a 1-week period. The results are as follows: 1. The eugenol-free zinc-oxide paste was the only material which exhibited no statistically significant difference between the die scribes and those of the sample. 2. The setting reaction of the eugenol-free-zinc oxide paste was a saponification reaction, resulting in the production of an insoluble soap. 3. With polyether, silicone, and zinc oxide-eugenol paste, there was a statistical difference between the die and the respective samples at the immediate reading and throughout the experiment. Polyether showed the least difference, and zinc oxide-eugenol paste the greatest.

Chemical Phenomena↗