Safety and Efficacy of the Apexum Ablator

Periapical lesions consist of inflammatory tissue replacing the bone surrounding the root-tip (apex) and are caused by bacteria present in an infected root canal (Metzger 2000). Endodontic (root canal) treatment is performed to eliminate these bacteria from the root canal and prevent its recontamination. The periapical lesion is expected to heal in response to this procedure, with new bone replacing the soft tissue of the lesion. The healing of the lesion may last 6-48 months, depending on its size and individual healing rate (Wang et al 2004). Not all lesions heal accordingly. Those which fail to heal are subjected to either non-surgical re-treatment or to a surgical procedure called "apicoectomy" (Kim \& Kratchman 2006). The surgical procedure consists of cutting the gums, accessing the periapical tissue through a hole drilled in the cortical bone, followed by curetting the soft tissue out of its bony crypt. After such surgical procedure, bone healing is much quicker (Kvist \& Reit 1999) and even relatively large lesions may heal within 3-6 months. Nevertheless, pain and swelling usually inflict great discomfort causing patients to lose up to 6 working days (Kvist \& Reit 2000). It is common practice to delay the final dental restoration (crown or bridge) for as long as the periapical lesion has not healed. Even though a surgical intervention could significantly reduce the waiting time, it is not commonly applied due to following: (a) Pain, discomfort and loss of working days, (b) High cost (c) Inaccessibility of many root tips, due to anatomical reasons. Apexum has developed a family of miniature, minimally invasive surgical tools, facilitating highly innovative methods for the treatment of periapical lesions associated with root canal infection. The Apexum Ablator device allows access to the periapical tissues through the root-canal following the commonly accepted root-canal procedures. The inserted tool grinds the periapical lesion, followed by washing out and aspiration of the ground material. In the present study, the safety and efficacy of the Apexum Ablator will be assessed in patients with periapical lesions associated with root canal infection by using this clinical investigational plan.