Indirect Pulp Capping
Indirect pulp capping is the treatment procedure to the decayed dentin is incompletely removed and is treated with the bio-compatible material. This helps in avoiding the exposure of pulp tissue to the oral environment and prevents other problems like tooth sensitivity. In this article, there is a brief discussion on the indirect pulp capping. Let us examine them.
Indirect pulp capping therapy:
The procedure involving a tooth with a deep carious lesion where carious dentin removal is left incomplete, and the decay process is treated with a bio-compatible material for some time in order to avoid pulp tissue exposure and is termed as indirect pulp capping.
A radiopaque base is placed over the remaining affected dentin to stimulate healing and repair. The tooth then is restored with a material that deals the involves dentin from the oral environment
- Reduction of hyperemia in pulp.
- Remineralization of carious or precarious dentin.
- Reduction of anaerobic bacteria.
- Formation of reparative dentin.
- Pulp vitality maintained.
- Continued normal root closure in immature permanent teeth.
- Indirect pulp therapy is utilized when pulpal inflammation has been judged to be minimal and complete removal of caries would probably cause a pulp exposure.
- Careful diagnosis of the pulpal status is completed before the treatment is initiated.
- The tooth is anesthetized and isolated with rubber dam.
- All the caries except that immediately overlying the pulp is removed.
- Care must be taken to eliminate all the caries at the dentin-enamel junction.
- If there is a communication of the caries with the oral cavity, the carious process will continue, resulting in failure of treatment.
- Care must also be taken while removing the caries to avoid exposure of the pulp.
- The use of a large round bur is best to remove the caries.
- The utilization of a spoon excavator when approaching the pulp may cause an exposure by removal of a large segment of decay and hence should be used cautiously.
- Not all undermine enamel is removed, as it will help to retain the temporary restoration.
- After all the caries, except that just overlying the pulp, has been removed, a sedative filling of either zinc oxide -eugenol (ZOE) or calcium hydroxide is placed over the remaining carious dentin ad areas of deep excavation.
- The tooth may then be restored with ZEO or amalgam.
- If the remaining tooth structure is insufficient to retain the temporary filling, a stainless steel band or temporary crown must be adapted to the tooth to maintain the dressing within the tooth.
- If this preliminary caries removal is successful, the inflammation will be resolved and deposition of reparative dentin beneath the caries will allow subsequent eradication of the remaining caries without pulpal exposure.
- The sedative dressing to be used in indirect pulp therapy must be either calcium hydroxide or ZOE.
- The treated tooth is reentered in 6 to 8 weeks and the remaining caries is excavated.
- The rate of reparative dentin deposition has been shown to average 1.4 microns per day following cavity preparations in the dentin of human teeth.
- The rate of reparative dentin formation decreases markedly after 48 days.
- If the initial treatment was successful, when the tooth is reentered the caries will appear to be arrested.
- The color will have changed from deep red rose to light gray or light brown.
- The texture will have changed from spongy and wet to hard, and the caries will appear dehydrated.
- Practically all bacteria are destroyed under ZEO and calcium hydroxide dressing sealed in deep carious lesions.
- Following the removal of the remaining caries, the tooth may be permanently restored. The usual procedure of pulpal protection with adequate base is of course mandatory before placement of permanent restorations.
- The reentry restorative procedure is still questionable.
- Research has shown that carious dentin will remineralize with the initial restoration. If the restoration has a good margin and at the recall visit a layer of secondary dentin is evident, reentry is not necessary.
Ideally, used when pulpal inflammation has been judged to be minimal and complete removal of caries would cause a pulp exposure.
- Any signs of pulpal or periapical pathology.
- Soft leathery dentin covering a very large area of the cavity, in a non restorable tooth.
- The restorative material should seal completely the involved dentin from the oral environment.
- The vitality of the tooth should be preserved.
- No prolonged post-treatment signs or symptoms of sensitivity, pain or swelling should be evident.
- The pulp should respond favorably and tertiary dentin or reparative dentin should be formed, as evidence by radiographic evaluation (1.5 microns/day after 30 days of pulp capping).
- There should be no evidence of internal resorption or other pathologic changes.
Infected versus affected dentin:
- Infected dentin is highly denineralized whereas, affected dentin has intermediately demineralized.
- Infected dentin is unremineralizable, whereas, affected dentin is remineralizable.
- Infected dentin is superficial layer, whereas, affected dentin is deeper layer.
- Infected dentin has lacking sensation, but affected dentin is sensitive.
- Infected dentin can be stained by 0.5% fuschin or 1.0 acid red solution in 0.2% propylene gycol. But, affected dentin does not stain.
- In infected dentin, the inter-bular dentin is greatly demineralized, with regular scattered crystals. Presence of deteriorated collagen fibers that have only distinct cross bands and no interbands. These should be excavated.
- In affected dentin, the inter-bular dentin partially demineralized, but apatite crystals bound like fringes to the sound collagen fibers with distinct cross bands and interbands. These should be left to remineralize.
The above article discusses briefly about indirect pulp capping. Individuals suffering with pulp damage must consult a professional dentist and go for a thorough diagnosis. One must also know about various treatment options and preventive measures.