A Computed Tomographic and Pathological Study of Equine Cheek Teeth Infundibulae Extracted From Asymptomatic Horses. Part 2: MicroCT, Gross, and Histological Findings

Abstract

Background: Equine maxillary cheek teeth infundibulae are frequently affected by developmental and acquired disorders, but the imaging, gross, and histological features of normal and abnormal infundibulae remain incompletely understood. Objective: To perform MicroCT, gross examination, and histology on sectioned teeth and compare the imaging and anatomical findings. Study design: Ex vivo original study. Methods: Eight maxillary cheek teeth of different ages and with varying grades of unilateral ( n = 5) or bilateral ( n = 3) occlusal infundibular caries were extracted from equine heads obtained from an abattoir. The teeth were imaged by MicroCT, then transversely sectioned and grossly and histologically examined, with the imaging and gross and histological anatomical findings examined and compared. Results: Fifteen infundibulae, including two without occlusal caries had subocclusal cemental hypoplasia or caries. One infundibulum without occlusal caries had no subocclusal cemental defects. Histologically, hypoplastic cemental areas consisted of irregularly-shaped, wide central channels, with multiple, large, cylindrical side-branches that extended peripherally to a variable extent. Cementum with extensive, wide, empty channels, and cementum with a more irregular moth-eaten appearance had dark or eroded gross appearance and a low HU on CT. Some infundibulae had cement-free areas that only contained fragments of collagen-like material, especially at their apical aspects (apical cemental hypoplasia). Carious subocclusal areas had connections with the occlusal surface and had disrupted cemental architecture, including of their central vascular channel that, along with their side branches, contained degraded food, and cemental debris. Main Limitations: No clinical histories or accurate ages were available for these eight teeth. Conclusions: Hypoplastic cemental lesions, including at central linear and apical sites, histologically contain areas with multiple wide-branched, cylindrical channels or even areas of total cement hypoplasia visible on gross sections When such cemental defects contact the occlusal surface due to normal wear, food impaction, and caries can ensue.

Morphological and radiological mapping of dental cusps in relation to spatial constraints on tooth shape of one-humped camel (Camelus dromedarius)

“…The short length crowns are brachydont and are adapted for soft diet and the hypsodont ones for long crowns are suitable for harder and dry food. Although previous radiological studies have been performed on the teeth of camel and equines [ 19 – 22 ], the dental cusps configurations have been neglected by many researchers [ 23 , 24 ]. Surprisingly, we are not aware of any studies addressing the morphological characteristics of camel teeth, and therefore, the present work aimed to provide more anatomical knowledge about the teeth of one-humped camel, in addition to clarifying the arrangement pattern of its dental cusps.…”

A Retrospective Observational Cohort Study on the Expiration of Maxillary Cheek Teeth Infundibula in 217 Horses

“…Numerous studies have reported on the development and anatomic structure of the cheek tooth infundibula. [21][22][23][24][25] These reports have focused on the development, [26][27][28] and therapy, [29][30][31][32] of infundibular cemental hypoplasia and infundibular caries. The authors are unaware of previous reports examining the timing of infundibular senescence in cheek teeth.…”

Connections between the internal and the external capsules and the globus pallidus in the sheep: A dichromate stain X‐ray microtomographic study

“…The use of micro‐CT (µ‐CT) has been recommended to characterize microstructural features of bone and soft tissues to obtain, in a non‐destructive manner, accurate 2D images in invertebrate and vertebrate samples (de Bournonville, Vangrunderbeeck, & Kerckhofs, 2019; de Crespigny et al., 2008; Descamps et al., 2014; Gignac & Kley, 2014; Heimel et al., 2019; Koç, Aslan, Kao, & Barber, 2019; Metscher, 2009; Pauwels, Van Loo, Cornillie, Brabant, & Van Hoorebeke, 2013; Rüegsegger, Koller, & Müller, 1996; Shearer, Bradley, Hidalgo, Sherratt, & Cartmell, 2016; Swain & Xue, 2009). In veterinary research, µ‐CT studies have mainly focused on the locomotor apparatus and associated diseases (Dedrick et al., 1993; Horbal, Smith, & Dixon, 2019; Lill, Gerlach, Eckhardt, Goldhahn, & Schneider, 2002; Salmon, 2020).…”

“…In veterinary research, µ-CT studies have mainly focused on the locomotor apparatus and associated diseases (Dedrick et al, 1993;Horbal, Smith, & Dixon, 2019;Lill, Gerlach, Eckhardt, Goldhahn, & Schneider, 2002;Salmon, 2020).…”