Access cavity preparation- Rules of thumb
1. To remove the entire roof of the pulp chamber so that the pulp chamber can be cleaned and canal entrance exposed.
2. To enable root canals to be located and instrumented by providing direct-line access to the apical third of the root canals.
3. To avoid damage to floor of the pulp chamber. Natural floor tends to guide an instrument in to the canal orificefloor tends to guide an instrument in to the canal orifice.
4. To enable a temporary seal to be placed.
5. To conserve as much sound tooth tissue as possible compatible with above.
