Relationship between Tooth Replacement Rate and Tooth Size in Cichlid Fishes

Teeth are mineralized structures located within the oral cavity that play a critical role in food acquisition and processing across vertebrate species. Proper regulation of tooth formation, spacing, and replacement is essential for maintaining functional dentition, and disruptions to these processes can contribute to craniofacial abnormalities in humans. Investigating the developmental mechanisms that influence tooth regeneration provides insight into both evolutionary adaptation and dental health. Unlike mammals, many teleost fishes continuously replace their teeth throughout life, making them valuable models for studying patterns of dental renewal.
Cichlid fishes exhibit substantial diversity in dentition and feeding strategies, providing an opportunity to examine how tooth replacement dynamics vary among species. In this study, individuals derived from two cichlid species with contrasting dental phenotypes, Copadichromis azureus (CA) and Dimidiochromis compressiceps (DC), were used to investigate the relationship between tooth replacement rate and tooth size. Tooth replacement activity was quantified by counting newly mineralizing teeth identified through sequential vital staining techniques, while tooth size measurements were obtained from previously collected morphological data.
By comparing patterns of tooth replacement with variation in tooth size, this study aims to determine whether species with larger teeth exhibit different rates of dental renewal than those with smaller teeth. Characterizing these patterns in cichlids contributes to a broader understanding of how tooth size and regeneration are coordinated in polyphyodont vertebrates and may provide insight into conserved mechanisms underlying vertebrate tooth development and replacement.