An enigmatic hypoplastic defect of the deciduous canine

Abstract

A roughly circular hypoplastic defect restricted to the labial enamel surface of the deciduous canine is described. This pathology is quite common in available samples of Upper Paleolithic and Neolithic children and a cadaver sample of recent Calcuttans, affecting 44% to 70% of individuals. It is rare in a Neanderthal sample and in children from a clinical practice in Vancouver. The lesion occurs twice as commonly in the lower jaw. The defect appears to commence at or after birth owing to localized pressure on thin or nonexistent alveolar bone overlying the bulging crypt of the deciduous canine. Population differences in the incidence of the pathology probably reflect innate and acquired variation in hard and soft tissue thicknesses in this region.

Localised enamel hypoplasia of human deciduous canines: genotype or environment?

“…This suggests that differences in nutritional status, or obstetric and paediatric care, may be important aetiological factors. 1,6,8 Skinner 4 has looked at the onset and duration of the lesion in detail and notes that the time interval during which a specific defect formed can be determined by relating the height of the defect to rates of deciduous canine formation. An intermediate formation rate for the deciduous canine is 0.33 mm per month, corresponding to an average time of 5.2 months for the form ation of the defect.…”

“…Skinner 4 further suggested that minor trauma to the developing canine crown of neonates (for example, sharp objects placed in the mouth) is an important environmental factor. At birth the cortical bone forming the labial bulge of the crypt of the primary canine is either thin or absent, and thus the crown may not receive adequate protection from early physical trauma (Fig.…”

“…2). Skinner 4 has argued that this differentiates the canine with respect to other adjacent primary teeth, which are either less labially positioned, or have largely completed crown Localised enamel hypoplasia of human deciduous canines: genotype or environment?…”

“From the mouth of a child”: dental attributes and health status during childhood in Mesolithic India

“…Although LEH and pitpatch hypoplasia were observed in the permanent teeth of the Damdama skeletons, LHPC was observed in the only sub-adult with deciduous teeth (DDM 5). Following a pattern of expression commonly observed in clinical studies of the trait, the maxillary canines were unaffected while both mandibular canines exhibited this 'plane-form' type of EH (Skinner andHung, 1986, 1989;Hillson and Bond, 1997). The labial surface of mandibular right and left primary canines were affected though the defects exhibited significant asymmetry in trait expression ( Figure 5); the number, size, and location of defects were different in antimeres.…”

“…Linear enamel hypoplasia (LEH) is the most commonly observed and studied form of EH and more frequently affects permanent than deciduous teeth (Goodman and Rose, 1990). Other expressions of enamel hypoplasia include depressed areas of enamel known as 'pit-patches' (Goodman et al, 1992), cuspal enamel hypoplasia of molar teeth (Ogden, 2008), and LHPC (Skinner, 1986). Although LEH and pitpatch hypoplasia were observed in the permanent teeth of the Damdama skeletons, LHPC was observed in the only sub-adult with deciduous teeth (DDM 5).…”