The Incidence, Nature, and Clinical Significance of Palatal Invaginations in the Maxillary Incisor Teeth

IT is quite obvious, clinically, that caries in or about the palatal cingulum pit occurs with considerable frequency and the carious focus seems to be the pit itself (sometimes called the foramen coecum) (Fig. 1). Again, some of these teeth give depressed vitality reactions-though soon after eruption the point of a fine probe applied to the pit in the cingulum of the tooth may cause acute pain as if an exposure of the pulp were present. Occasionally it has been noticed that a patient presents with an apparen'ly normal incisor-usually a second maxillary-which, without any history of trauma or carious cavitation, has become abscessed, or failed to complete root development, or both (Fig. 2). The matter becomes of great clinical importance if it can be shown that these developmental defects are present in a significant proportion of all cases, for the second maxillary incisor is a most important member of the dentition xsthetically and replacement by artificial means in the young person is a formidable problem. During the course of this investigation a classification of invagination was adopted dependent largely upon degree of affection. It is realized that the Classes I-IV (in Group la) are an artificial arrangement and that many specimens may occur that fall between, but some assessment of degree was necessary for charting purposes, and all doubtful cases were referred to the next lower group.