Dental adhesives play an important role in dentistry today.
However, to achieve long-term preservation of teeth, which is the clinician's foremost concern, dental adhesives alone cannot be completely relied upon to produce the desired results.
In this paper, five rules for the achievement of long-term tooth preservation are presented, and the results of preliminary tests employed to evaluate the validity of these rules are reported. Clinical techniques for each case are presented. The five rules are as follows:
1. To preserve as much pulp substrate as possible
2. To seal the tooth completely using dental adhesive
3. To select restorations and dental adhesives which avoid stress concentration
4. To restore tooth substrate and pulp to a sound vital tooth state by means of sterilization before sealing
5. To strengthen the tooth by using fluoride-releasing materials, under the assumption that a secure seal may not always be obtainable
With regard to rules 2, 4, and 5, the application method and efficacy of a new dentin treatment technique (AD gel method) invented by the author, in which the affected dentin is cleaned and sterilized, and dentinal tubules are enlarged by partially dissolving their organic components to promote thicker resin tags, are detailed.