Morphology of the physiological foramen:: I.: Maxillary and mandibular molars

Information concerning the anatomy of the physiological foramen is limited. The aim of this study was to investigate the distance between the physiological and anatomical apex, accessory foramina frequency, and the shape and diameter of the physiological foramen in maxillary and mandibular molars. The apical anatomy of 523 maxillary and 574 mandibular molars from an Egyptian population was investigated by means of a computer-aided stereomicroscope (40 x magnification). The following results were obtained: (a) There was a high percentage of two physiological foramina in mesial (87.06%) and mesiobuccal (71.15%) roots of mandibular and maxillary first molars, respectively. (b) There was a high frequency of accessory foramina in maxillary mesiobuccal (33%) and mandibular mesial (26%) roots. (c) The most common physiological foramen shape was oval (70%). (d) The mean of the narrow and wide physiological foramen diameters was as follows: 0.20 to 0.26 mm in mandibular molars 0.18 to 0.25 mm in the maxillary mesiobuccal and distobuccal root 0.22 to 0.29 mm in the maxillary palatal root.