Preservation of vitality in young permanent immature teeth is imperative to allow completion of root formation in order to have the strongest root possible. If injury occurs resulting in pulpal necrosis before dentinogenesis is completed, retention of the tooth is compromised by diminished root length and thinness of dentin. The thinner dentinal walls of the root lead to increased root fracture. The decrease in root length results in less root-to-crown ratio and may lead to tooth mobility with resultant loss of attachment apparatus.
In a 4-year study, Cvek (1992) reported significant increase in cervical root fracture in endodontically treated immature teeth. Dependent on the stage of development, fractures ranged from 77% in teeth with the least root development to 28% with the most developed roots (Figures 17.1 and 17.2).
Direct pulp capping (Figure 17.3) and pulpotomy attempt to preserve pulpal vitality by the application of a medicament or dental material to the exposed pulp. Pulpotomy differs from pulp capping only in that additional pulp tissue is removed before placement of the pulp-capping agent. The success rates of these procedures following injury in the young teeth are highly successful (Cvek and Lundberg, 1983; Fuks et al., 1987). While there is much disagreement on these vital procedures versus pulpectomy and root canal filling, there is almost universal agreement these procedures are indicated in teeth with immature apices.
In young fractured teeth with pulp exposure, Cvek (1978) and Cvek and Lundberg (1983) have shown that inflammation and/or infection will be confined to the surface 2–3 mm. The underlying tissue will respond favorably to pulpotomy. Neither the exposure size nor time between injury and treatment up to 90 days is critical for healing when only the superficial layers of pulp are removed. It is usually not necessary or desirable to remove all the coronal pulp tissue. This partial pulpotomy is commonly referred to as a Cvek pulpotomy (Cvek, 1993) (Figures 17.4 and 17.5).
Many medicaments and materials have been used for pulp capping and pulpotomy. Traditionally, calcium hydroxide Ca(OH)2 has been the most widely used agent of choice (Figure 17.7). However, additional recent research has shown mineral trioxide aggregate (MTA) to be more biologic while producing better results (Abedi et al., 1996; Pitt Ford et al., 1996). MTA has become the agent of choice (Figures 17.6 and 17.7).
Healing is directly related to the capacity of the capping agent and restoration to provide a biologic seal against bacterial leakage while simultaneously forming a dentinal bridge. MTA provides a biologically active substrate to which cells are attached. Calcium released from the MTA reacts with phosphate in the tissue fluid to produce hydroxyapatite (Sarkar et al., 2002).
In the Cvek pulpotomy, only tissue judged to be inflamed is removed. Removal of tissue is accomplished with an abrasive diamond or round carbide bur using high-speed and copious water spray. All fibers of the pulp coronal to the amputation must be removed, otherwise hemorrhage will persist. After tissue removal is completed, the site is washed with sterile water or saline to remove all debris. Blowing air on the pulp is contraindicated because it will cause damage to the tissue from desiccation.
Hemorrhage control is obtained by light pressure on the pulp with a dampened cotton pellet. Hemostasis should be achieved in 1–2 min (Figures 17.4b, 17.4c and 17.5
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