Aim: To determine the prevalence of three canals in the mesial root of the first permanent mandibular molars, of patients who come for root canal treatment at the dental clinic of the Equinoctial Technological University, Quito, Ecuador from January 2013 to December 2017. Materiales and Methods : A descriptive observational study is presented, in a sample of 55 clinical histories of patients with root canal treatment at the dental clinic of the Health Sciences faculty "Eugenio Espejo" of the Equinoctial Technological University, between January 2013 to December 2017. After a review of the medical records of patients treated during this period of time and inclusion criteria, the selected radiographs were examined in a negatoscope with the help of a magnifying glass, by a single person trained in reading images and with experience in endodontic treatments. The findings were reported in spe...

 The Traumatic Bone Cyst is an intraosseous cavity that appears in the jaw of young patients. One of the most accepted theories is about bleeding inside the bone due to trauma, instead of the correct formation of the clot, the liquefactive necrotic clot is reabsorbed in another way, forming the cyst. The first objective of this clinical case is to return the functionality and correct health of the patient. The second objective is linked to the presentation of a specific clinical case, which will allow us to illustrate the treatment of the Traumatic Bone Cyst of a 16-year-old male patient, who attended an orthodontic consultation, being referred to an interconsultation with the surgery area. maxillofacial, due to discomfort in the lower right quadrant when chewing. As a complementary examination, the computerized axial tomography CT scan shows a radiolucent shadow compatible with a "bone...