Which of the following is not a suggested use for the material MTA?

Mineral Trioxide Aggregate (MTA) is a bioactive material commonly used in various endodontic procedures due to its desirable properties, such as biocompatibility, ability to promote healing, and sealing capability. While several clinical applications are recognized for MTA, including pulp capping, nonsurgical apical closure, and perforation repair, its use in obturation of accessory canals is not standard practice.

In the context of obturation, materials such as gutta-percha are typically preferred for sealing root canals, including accessory canals, due to their established effectiveness, handling properties, and ease of use. MTA, while it could theoretically be used in this scenario, is not specifically indicated for obturation purposes, especially when dealing with accessory canals, as it may not provide the same level of adaptation and ease of removal if retreatment is necessary.

Thus, while MTA has invaluable applications in vital pulp therapy, apexification, and repairing root perforations, the routine obturation of accessory canals falls outside its primary suggested uses in endodontic practice.