ABSTRACT
Vital bleaching of teeth is, increasingly, a popular esthetic desire. Bleaching agents are provided in over-the-counter as well as dental office bleaching kits. However, the effect of the bleaching agents on the enamel surface is not fully understood, and cautions approaches to their use are not usually explained to patients. In this study, an in vivo exposure of bleaching agents is used to evaluate the short and long-term effect on the enamel surface; the results are demonstrated by scanning with an electron microscope. Exposure to the bleaching agents for 14 days created an alteration of the enamel surface and caused exposure of the enamel prisms. Moreover, a 21- to 90-day post-exposure SEM evaluation demonstrated alteration of the surface enamel, indicating exposure of the enamel prismatic layer, frequently to the depth of the enamel rods and possibly the dentin.
Subject(s)
Dental Enamel/drug effects , Tooth Bleaching/adverse effects , Dental Enamel/ultrastructure , Humans , Microscopy, Electron, Scanning , Surface Properties , Time FactorsABSTRACT
Many methods of bleaching teeth and their effects on the surrounding tissues and pulp have been reported. The effect of bleaching agents on the enamel surface has received some investigation, but the products selected for the present study have not been included in previous scanning electron microscopic studies. In vitro scanning electron microscopic evaluation revealed that the enamel surface underwent considerable changes after 1 hour of exposure to one of four bleaching agents. These changes increased in direct relation to the length of time that the enamel surface was exposed to the oxygenation (bleaching) agent.
Subject(s)
Dental Enamel/drug effects , Oxidants/pharmacology , Tooth Bleaching , Carbamide Peroxide , Dental Enamel/ultrastructure , Humans , Materials Testing , Microscopy, Electron, Scanning , Peroxides/pharmacology , Polyvinyls/pharmacology , Time Factors , Urea/analogs & derivatives , Urea/pharmacologyABSTRACT
The effect of bleaching agents on the enamel surface was examined by scanning electron microscopy. The comparison of treated to untreated enamel revealed that the treated surface had increased surface change and porosity after the equivalent of 30 hours of exposure to the bleaching agent. The degree of alteration of enamel surface was not uniform and was influenced by cleanliness (oral hygiene) of the treated teeth and apparent variation in calcification. The enamel surface developed varying degrees of surface porosity and alteration.
Subject(s)
Citrates/pharmacology , Dental Enamel/drug effects , Dental Enamel/ultrastructure , Peroxides/pharmacology , Phosphoric Acids/pharmacology , Tooth Bleaching , Urea/analogs & derivatives , Acid Etching, Dental , Acrylic Resins , Carbamide Peroxide , Dental Enamel Solubility , Drug Combinations , Humans , Microscopy, Electron, Scanning , Polyvinyls/pharmacology , Porosity , Time Factors , Tooth Demineralization/chemically induced , Tooth Demineralization/pathology , Urea/pharmacologyABSTRACT
The effect on the permeability of prepared dentin treated with 25% tannic acid and 6% citric acid was compared with the untreated dentinal surface. Methylene blue was applied to the dentin surface after treatment to evaluate penetration into dentinal tubules. The tannic acid solution reduced or prevented dye penetration of the dentinal tubules. Citric acid treatment permitted severe penetration. The 25% tannic acid solution removed the smear layer while inhibiting penetration of the dye.
Subject(s)
Dentin Permeability/drug effects , Dentin/drug effects , Hydrolyzable Tannins/pharmacology , Tannins/pharmacology , Tooth Permeability/drug effects , Acid Etching, Dental/methods , Citrates/administration & dosage , Citrates/pharmacology , Citric Acid , Dental Cavity Preparation , Dentin/ultrastructure , Humans , Hydrolyzable Tannins/administration & dosage , Methylene Blue , Microscopy, Electron, ScanningABSTRACT
The effects of a 25% tannic acid solution applied to the surface of prepared dentin was compared with untreated prepared dentin surfaces. The following results were demonstrated by electron microscope observation: (1) cavity preparations created an amorphous dentinal smear layer, (2) placement of a 25% tannic acid solution for 15 seconds removed the smear layer, (3) the contents of the dentinal tubules were not removed and no enlargement of dentinal tubules was found, and (3) a clean dentinal surface was observed.
Subject(s)
Dentin/ultrastructure , Hydrolyzable Tannins/therapeutic use , Tannins/therapeutic use , Dental Cavity Preparation/methods , Dentin/drug effects , Humans , Hydrolyzable Tannins/administration & dosage , Microscopy, Electron, Scanning , Pilot ProjectsABSTRACT
A scanning electron microscope was used to evaluate the cleansing properties of a 25% tannic acid solution on the dentinal surface in the pulp chamber of endodontically prepared teeth. This was compared with the amorphous smear layer of the canal with the use of hydrogen peroxide and sodium hypochlorite solution as an irrigant. The tannic acid solution removed the smear layer more effectively than the regular cleansing agent.
Subject(s)
Dental Pulp Cavity/ultrastructure , Dentin/ultrastructure , Hydrolyzable Tannins/therapeutic use , Root Canal Irrigants/therapeutic use , Tannins/therapeutic use , Dental Pulp Cavity/drug effects , Dentin/drug effects , Humans , Hydrogen Peroxide/therapeutic use , Microscopy, Electron, Scanning , Root Canal Therapy , Sodium Hypochlorite/therapeutic useSubject(s)
Osteoporosis/prevention & control , Aged , Aged, 80 and over , Female , Humans , Osteoporosis/etiologyABSTRACT
The technique described has been used with good success. Failures have been negligible and may be attributed to poor technique of mixing of the ionomer, since it is difficult to completely standardize procedures. The advantages are caries resistance, bonding with minimal preparation, and pulpal protection while providing improved esthetics (Fig. 2).
