Evaluation of the Effect of Leukocyte and Platelet-rich Fibrin on Clinical and Radiographic Healing After Periradicular Surgery: Randomized Controlled Clinical Trial.

Materials and Methods:

Apical periodontitis is a local response of the bone around the root tip of the tooth to necrosis of the pulp tissue. In the treatment of apical periodontitis, it is primarily aimed to remove the pathogenic microorganisms responsible for the infection with root canal treatment. The success of root canal treatment depends on the complete repair and regeneration of periapical tissues, and most of the periapical lesions heal satisfactorily after root canal treatment, but there are cases where infection and persistent symptoms persist despite root canal treatment. In these cases, periapical surgery with endodontic retreatment is required to eliminate pathological tissues, eliminate the source of irritation and support the healing process. For this purpose, 2 different periapical surgical methods are performed. In the first method, which is a more radical technique, the tip of the root of the related tooth responsible for apical periodontitis is resected (apicectomy) after curettage of the bone defect area. In the second method, in which the tooth tissue is preserved with a more conservative approach, only the defect area is curetted without root tip resection. Different results regarding the clinical success of these two methods have been reported in the literature.

In many studies, apicectomy is accepted as principal part of periapical surgical procedures and a prerequisite for the success of treatment but, roots that have already weakened and thinned due to periodontitis become more prone to fracture. In addition, especially in cases where the ratio between crown and root length is impaired, the stability of the restoration is adversely affected and the stability of the tooth in the socket may become questionable in the long term. In the literature, there are only a few case reports and a clinical study evaluating the clinical success of periapical surgery performed with periapical curettage without apicectomy following endodontic retreatment.

In recent years, many studies have been carried out to increase the success of apical surgery by accelerating and increasing the formation of new bone in the defect area with regenerative applications. Leukocyte and platelet-rich fibrin (L-PRF) is a second-generation platelet concentrate that forms an organized fibrin network in which platelets and leukocytes are trapped. In the few studies in the literature regarding the use of L-PRF alone without combining with a graft, in periapical surgery, apical surgery has been performed with root tip resection. In the literature, there is only one case series evaluating the effect of L-PRF application on periapical intraosseous defect after apical curettage without apicectomy on clinical and radiological healing.

In the treatment of apical periodontitis cases whith persistant symptoms and infection despite root canal treatment; more successful long-term results are aimed to be achieved by curettage of the periapical lesion and placement of L-PRF in the intraosseous defect after endodontic retreatment providing acceleration of apical bone regeneration, reducing clinical symptoms, and preserving the tooth root with a more conservative approach.