An ex-vivo study was performed on vertically-mounted equine maxillary cheek teeth that had caries of 30 infundibulae, using high and low speed contra-angle dental drills and Hedstrom files to debride infundibular food debris and carious dental tissues. This technique effectively debrided 27/30 infundibulae of mean depth 19 mm (range 9.4-34.3mm) as assessed by computed tomographic (CT) imaging. The debrided infundibulae were treated with sodium hypochlorite, EDTA and a bonding agent, and then then filled in layers with endodontic restoration materials. Further CT imaging and direct examination of sectioned restored teeth showed 6/30 infundibulae, including three that were incompletely debrided, to have defects between the restoration and the infundibular wall/apex. Twenty one of the remaining 24 infundibulae contained air bubbles, largely within restorations. It is concluded that the use of drills and Hedstrom files is effective in debriding carious infundibulae but improved techniques and materials are required to more effectively fill infundibulae with restorative material.