(3) In the literature, this malformation has also been referred as interstitial cusp, tuberculated premolar, odontome of the axial core type, evaginated
odontome, occlusal enamel pearl, occlusal anomalous tubercule, supernumerary cusp and dens evaginatus of anterior teeth.4 Review of the reported cases indicated that this condition usually affects the maxillary incisor teeth and those talon cusps of the mandibular incisors are extremely rare.
(2002), explicitly accepted the continuity between the tubule and capsule wall asserted by Weill (1934), and Chapman and Tilney (1959b) even termed the base of a discharged stenotele the "evaginated
capsular wall." Westfall and Hand (1962) and West-fall (1965) demonstrated that the tubule is continuous with the inner layer of the capsule wall.
To determine the nature of the morphological changes that occur during thyroid development in the chick embryo, we measured the length, width, and depth of the evaginated
region (the thyroid pit) from chick embryos of stages 13, 14, and 15 of development (Table 1, Fig.