American Dental Association Specification Research Articles

Addendum to American National Standards Institute / American Dental Association Specification No. 34 for Dental Aspirating Syringes

Addendum to American National Standards Institute / American Dental Association Specification No. 34 for Dental Aspirating Syringes

Revised American National Standards Institute / American Dental Association Specification No. 21 for Dental Zinc Silicophosphate Cement

Revised American National Standards Institute / American Dental Association Specification No. 21 for Dental Zinc Silicophosphate Cement

Revised American National Standards Institute / American Dental Association Specification No. 5 for Dental Casting Gold Alloy

Revised American National Standards Institute / American Dental Association Specification No. 5 for Dental Casting Gold Alloy

New selenium-containing silver amalgam.

An investigation was made to determine the effects of the addition of selenium to the silver-tin amalgam alloy. The addition of 0.2 wt% to 0.6 wt% selenium in the alloy completely eliminated the cytotoxicity, evaluated by the 51Cr release assay and morphology, of the silver amalgam on the L cells and JTC-12 cells. The physical properties of the amalgam containing 0.2 wt% selenium in the alloy were tested according to the American Dental Association Specification No. 1 for Alloy for Dental Amalgam and were found to meet the requirements.

Revised American National Standards Institute / American Dental Association Specification No. 13 for Denture Cold-curing Repair Resin

Revised American National Standards Institute / American Dental Association Specification No. 13 for Denture Cold-curing Repair Resin

Revised American National Standards Institute / American Dental Association Specification No. 9 for Dental Silicate Cement

Revised American National Standards Institute / American Dental Association Specification No. 9 for Dental Silicate Cement

Revised American National Standards Institute / American Dental Association Specification No. 25 for Dental Gypsum Products

Revised American National Standards Institute / American Dental Association Specification No. 25 for Dental Gypsum Products

Elastomeric impression materials: Effect of bulk on accuracy

Impression trays were fabricated providing 2, 4, and 6 mm spaces to determine the stability and accuracy of nine elastomeric impression materials on a simulated full crown preparation steel die. The interface space of 2 mm produced the most accurate impressions for all of the materials tested. All impression materials except one fell within the revised American Dental Association Specifications. The clinical-type tests, using castings on dies poured from these materials, corroborated the acceptance of those materials and techniques exhibiting the least dimensional change.

New American Dental Association specification no. 30 for dental zinc oxide-eugenol type restorative materials

New American Dental Association specification no. 30 for dental zinc oxide-eugenol type restorative materials

Porosity in the base metal removable partial denture casting alloys relative to observable metallographic features

A series of tensile test pieces of the dimensions stated in the American Dental Association Specification No. 14 were produce using both nickel-base and cobalt-base removable partial denture casting alloys. Normal dental casting techniques were employed. Appropriate sections from each specimen were sectioned to half of their original thicknesses, embedded in heat-and pressure-cured conducting mounts, and polished for metallurgical examination. A double electrolytic etching technique was used, employing serially two solutions, in order to maximize the amount of metallographic detail visible. The method proved particularly valuable in the case of the nickel-base alloy as it indicated the presence of considerable interdendritic segregation. The incidence of porosity was evaluated throughout all sections of the specimens and, although found to be especially prevalent in those regions where gross shrinkage effects might be expected to occur, it was also shown to have a diffuse intergranular and interdendritic distribution.

Influence of Internal Stress of the Strength of a Cold-Cured Acrylic Resin

The transverse rupture strength of a cold-cured acrylic resin may be increased by subsequent heating (CAUL, STANFORD, and SERIO, JADA 44: 295, 1952). This may be the result of postpolymerization of residual monomer. Another strengthening factor is the relief of internal stress (MATTHEWS, Br Dent J 67: 116, 1954). Data obtained under conditions in which postpolymerization can be neglected are reported here. Specimens were prepared from mixtures of polymeric powder and a liquid monomer, without heating, according to the manufacturer's instructions and in accordance with American Dental Association Specification No. 12. Residual monomer was removed by extraction with water at 37 C. Specimens were then allowed to equilibrate for several months in air. Dumbbell specimens of a half inch gauge length and a quarter inch by a sixteenth inch

New American Dental Association Specification No. 25 for Dental Gypsum Products

New American Dental Association Specification No. 25 for Dental Gypsum Products

New American Dental Association Specification No. 24 for Base Plate Wax Adopted

New American Dental Association Specification No. 24 for Base Plate Wax Adopted

New American Dental Association Specification No. 23 for Dental Excavating Burs Adopted

New American Dental Association Specification No. 23 for Dental Excavating Burs Adopted

Revised American Dental Association Specification No. 22 for Intraoral Dental Radiographic Film Adopted

Revised American Dental Association Specification No. 22 for Intraoral Dental Radiographic Film Adopted

American Dental Association Specification No. 1 revised

American Dental Association Specification No. 1 revised

New American Dental Association Specification No. 21 adopted

New American Dental Association Specification No. 21 adopted

Council adopts American Dental Association Specification No. 18 (Alginate Impression Material)

Council adopts American Dental Association Specification No. 18 (Alginate Impression Material)

New American Dental Association Specification no. 20 adopted

New American Dental Association Specification no. 20 adopted

Zinc oxide and eugenol cements for permanent cementation

A group of zinc oxide and eugenol cements designed for permanent cementation were compared to zinc phosphate cement on the basis of compressive strength, tensile strength, solubility, and film thickness. In addition, the amount of tensile force required to remove standardized gold inlays from the prepared cavity when they were cemented with zinc phosphate cement and various zinc oxide and eugenol materials was determined. The zinc oxide and eugenol materials were inferior to zinc phosphate cement in respect to compressive strength, but were comparable when tested under tension. Only one of the zinc oxide and eugenol cements complied with the American Dental Association Specification for the film thickness of zinc phosphate cement. The solubility in both acid and water of two of the materials was comparable to zinc phosphate cement, while the remaining three materials demonstrated slightly greater disintegration under the conditions of the test. Inlays cemented with two of the zinc oxide and eugenol preparations required approximately the same tensile force to remove them as did inlays cemented with zinc phosphate cement.