ENDODONTIC therapy is required on an immature tooth with an open apex,
ensuring maturogenesis is the treatment of choice. Until the tooth
is fully mature, the apex is open and the root canal walls are thin.
Closure of the apex is needed in the root development of immature teeth,
but continued root development and dentin formation are also needed.
We want to allow not just apexogenesis—the closure of the apex—but maturogenesis—the
continued maturation of the tooth, the normal process of root and apex
formation with eventual closure of the apex, and continued dentin formation
along the root walls to increase their thickness and length. Canal
walls need thickness and an appropriate internal shape if the mature tooth
is to be strong. The thin canal walls and open apex make root-canal
therapy on an immature tooth extremely difficult. Keeping the pulp
alive and allowing the tooth to mature is preferred because the mature
tooth is a much better candidate for successful root-canal therapy.
If the pulp is necrotic, apexification may be required.
In this procedure, necrotic tissue is removed, and apex closure is induced.
The desired effect of apexification is a calcified barrier across the open
apex to allow for obturation with gutta-percha. However, apexification
does not allow for the development of the root-canal walls. To achieve
apexification, the canal must be free of infection. Calcium hydroxide
is used to promote apical closure by stimulating the formation of a calcified
barrier. The successful formation of the hard-tissue barrier is usually
determined by tactile sensation.
Mineral trioxide aggregate (MTA) can also be used
to create an artificial apical barrier. MTA is placed into the canal
to create an apical plug of 3?4 mm. Once the MTA is set, the canal
can be obturated with gutta-percha.
Encouraging maturogenesis is the desired treatment.
If maturogenesis cannot be achieved, then apexification by calcium hydroxide
or artificial closure using MTA must be utilized. The ultimate success
can be determined only on recall with the absence of pain and pathology.
is the treatment of choice.