STAGE-DEPENDENT HISTOMORPHOGENESIS OF THE ALVEOLAR CRYPT DURING PRIMARY TOOTH ERUPTION IN KITTENS
DOI:
https://doi.org/10.35220/2523-420X/2026.2.2Keywords:
tooth eruption, primary teeth, dental follicle, alveolar crypt, alveolar bone, osteogenesis, kittens, histomorphology.Abstract
Tooth eruption is a spatially and temporally coordinated process in which alveolar bone resorption and formation are integrated with dental follicle cell differentiation and establishment of the future periodontal complex. Nevertheless, the regional histoarchitectural features of the bony crypt during eruption of primary teeth in diphyodont mammals remain insufficiently characterized. Aim of the study. To characterize stage-dependent histomorphogenesis and vestibulolingual asymmetry of the alveolar crypt surrounding mandibular anterior primary tooth germs in kittens and to relate these changes to the direction of crown displacement during eruption. Materials and methods. Post-mortem mandibular material from 10 deceased kittens was examined. Two groups were distinguished using macroscopic developmental criteria: mandibles with a smooth alveolar surface (n=5) and mandibles in which primary tooth crowns protruded above the mandibular surface (n=5). Specimens were fixed in 10% neutral formalin, gently decalcified with Trilon B, processed routinely in paraffin, sectioned, and stained with hematoxylin and eosin or Van Gieson stain. Microscopy and photodocumentation were performed using an Olympus BX41 microscope at ×100 and ×200. The analysis was descriptive and histomorphological. Results. At the follicular stage, a thin periosteal layer generated trabeculae oriented parallel and perpendicular to its surface. Bone maturation was spatially heterogeneous: vestibular trabeculae were predominantly eosinophilic and appeared less advanced in ossification, whereas lingual trabeculae were more basophilic and exhibited greater osteocytic incorporation. Intertrabecular spaces progressively acquired reticular and myeloid tissue. Concomitantly, organized collagen bundles, endosteal structures, and concentric bone lamellae developed. This asymmetry coincided with a change in crown orientation from oral to oblique vestibular. Conclusions. The primary tooth crypt in kittens develops non-uniformly and displays marked vestibulolingual asymmetry of ossification. These findings support a model in which spatially selective alveolar bone remodeling establishes the morphological conditions for directed tooth displacement while the periodontal attachment apparatus is formed.
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