Bonding Ability to Dentin and Pulpal Irritability of a New Bonding System Using the Trial Materials METAFIL I and a 4-META Bonding Agent
1990 Volume 53 Issue 3 Pages 313-324
Details
1990 Volume 53 Issue 3 Pages 313-324
A new bonding system has been developed which is comprised of a UDMA base resin METAFIL I and a 4-META methyl methacrylate bonding agent which bonds to dentin. In vitro dentin bonding tests and in vivo pulpal irritation tests were carried out. The dentin bonding tests used human teeth which had been placed in 4℃ physiologic saline solution as soon as possible after extraction and had been stored in this way for several months. Five types of etching agent were used : 20% phosphoric acid (20-P), 25% phosphoric acid (25-P), 40% phosphoric acid gel (40-P), 10% citric acid-3% ferric chloride (10-3) and 0.5M EDTA at pH 7.4. GLUMA (10% glutaraldehyde-35% hydroxy-ethyl-methacrylate) was used as a primer after etching. Clearfil New Bond was used as a bonding agent for comparison with 4-META MMA. Composite resins used were the Clearfil-posterior chemical polimerization type in the case of Clearfil New Bond, and the METAFIL I light curing type in this case of 4-META MMA.
For the pulpal irritation test in vivo, METAFIL I composite resin with 4-META MMA bonding agent was placed in the teeth of Japanese monkeys. At the same time, other materials were also tested using the same monkeys as controls for comparison with the METAFIL I system. The ADA, FDI/ISO diagnosis system was used as a basis for evalvating pulpal irritation.
The following results were obtained :
1) The adhesive strength to dentin of 4-META MMA showed generally the same or slightly higher values compared with Clearfil New Bond.
2) The 10-3 solution and the 40-P gel proved to be the proper etching solutions.
3) The use of GLUMA as a primer had no particular effect.
4) The degree of pulpal irritability was the same or less than the other composite resin restorative materials.
5) There seemed to be no problems with clinical application of this system since the amount of reparative dentin resulting from pulpal irritation was slightly more than the control and no severe harmful effects were observed.
