Effects of restorative materials
In addition to the trauma of the preparation of the teeth restoration and the subsequent leakage of physical elements, the liberation of the subjects of restoration materials may have a negative influence on the masses. Over the years toxicity of restoration materials considered a primary cause inflammation of the pulp of the tooth and the breakdown of restorative procedures. However, recent studies have shown that toxic components in the restoration materials represent a hazard for the pulp than previously assumed (4). This was manifested in experimental studies, where dental materials in common use (dental amalgams, zinc phosphate cement, composites) were applied directly on the tissue of the tooth pulp and where the surface of the restoration was sealed bacteria-tight (17). These experiments have shown that the pulp around the sealed restoration resumed working condition. On the contrary, without restorations bacteria tight surface seals allowed the invasion of bacteria pulp-recovery interface, resulting in severe inflammatory lesions.
The risk of severe tooth pulp complication is even smaller when dentin barrier remains.
Dentin seems to serve as a detoxifying fabrics which high toxic substances are absorbed to the inner walls of the dentinal tubules (29). Dentin moreover buffers action of acids and alkalis (30). It is necessary to recognize, that in experiments in vitro and in vivo have shown that hydrophilic resin primer 2-hydroxyethyl methacrylate (HEMA) and a binder resin, monomer, triethylene glycol dimethacrylate (TEGDMA)used in modern restorative procedures, easily penetrate thin dentin wall after topical application (21, 31). Some adverse reactions are possible, including damage to the cells of the tooth pulp and allergic reactions in susceptible patients, but they were not confirmed prevails. Thus, the threat of pulp combined with modern restorative procedures do not seem to be as much related to materials, per se, as it is incorrect seal, which may result
The basic concept 2.4 pulpal response to bacterial leakage tooth/restore interfaces
- Leakage bacteria and bacterial products in tooth/restore interfaces causes inflammatory changes in the pulp through the dentin.
- Although these responses, as a rule, do not lead to tooth pulp failures they can cause painful symptoms and pulp of a tooth scars.
- Clinicians warning : do not leave the dentin expositions unprotected or poorly suited permanent or temporary restorations.
- There is a huge difference in infectious load pulp when large area dentin disclosed, for example. in full crown preparation relatively small and shallow cavity. On such exposures protective measures are particularly important.