An in vivo experimental model to assess furcal lesions as a result of perforation

Aim To design and validate a rat molar model of furcal perforation to allow investigation of the biological phenomena that follow and to explore its potential for evaluating repair materials under standardized conditions. Methodology Eighteen male Wistar rats were used. Surgical aseptic procedures were carried out in order to open the pulp chamber of a first molar tooth. A cavity was prepared on the floor of the pulp chamber using a ¼ round bur that created a communication between the furcation and the periodontal tissues. Six animals for each time point were sacrificed on days 14, 21 and 28 to assay morphological changes at the furcation region of molars. Maxillary bone was processed, removed and sectioned. Cellular infiltration, collagen deposition and bone resorption were assessed by histological analysis. Cellularity in the lesion area was determined by morphometric analysis. Data were analysed using parametric Student’s t‐test. Results A furcal perforation model was standardized in which both radiological outcome and periodontal tissue reactions could be assessed through evaluation of cellularity, osteoclast activity and collagen deposition. The morphometric analysis revealed a greater number of cells 21 day post‐surgery when compared with 14 days. Conclusion This animal model was suitable for radiological and histological evaluation of the processes that accompany surgical furcal perforation.