Thursday, September 4, 2014

Root-end induction (apexification)

The cases in which partial or total closure of an open apex can be achieved are:
1. vital radicular pulp in an immature tooth pulpotomy (see Part 10);
2. pulpless immature tooth with or without a periapical radiolucent area.

The success of closure is not related to the age of the patient. It is not possible to determine whether there would be continued root growth to form a normal root apex or merely the formation of a calcific barrier across the apical end of the root. The mode of healing would probably be related to the severity and duration of the periapical inflammation and the consequent survival of elements of Hertwig s sheath.
Inducing apical closure may take anything from 6 to 18 months or occasionally longer. It is necessary to change the calcium hydroxide during treatment; the suggested procedure is given below:
First visit   Thoroughly clean and prepare the root canal. Fill with calcium hydroxide.

Second visit   2 to 4 weeks later, remove the calcium hydroxide dressing with hand instruments and copious irrigation. Care should be taken not to disturb the periapical tissue. The root canal is dried and refilled with calcium hydroxide. Third visit   6 months later, a periapical radiograph is taken and root filled if closure is complete. This may be checked by removing the calcium hydroxide and tapping with a paper point against the barrier. Repeat the calcium hydroxide dressing if necessary. Fourth visit   After a further 6 months another periapical radiograph is taken, and the tooth root-filled if closure is complete. If the barrier is still incomplete the calcium hydroxide dressing is repeated. Fifth visit   This should take place 3 to 6 months later. The majority of root closures will have been completed by this time (Fig. 5).

Once again, however, reference must be made to the increasing use of MTA for root-end closure and other such endodontic procedures.