Guiding Forces in Murine Mid-Palatal Suture Establishment

Objectives: Despite thorough study of palate development, the formation of the mid-palatal suture is poorly investigated. This study aimed to translate knowledge of cranial suture biology to the mid-palatal suture, poising the orthodontic field for future innovation. Our objective was to characterize the establishment of this suture according to an expected combination of primary ossification centre expansion and site-specific midline extracellular matrix features, growth factors, resident cells, and mechanical stimuli.
Methods: We employed a pre-clinical murine model to charactize the mid-palatal suture spatiotemporally at the molecular and cellular level. We performed with stage-specific analyses of late embryonic, newborn, and early postnatal mice. Histomorphometrics, including protein immunofluorescence, multiplex mRNA in situ hybridization, and unbiased spatially resolved RNA-sequencing were employed to visualize the advancing maxillary bone fronts and their interactions with mid-palatal mediators of suture establishment.
Results: We identified essential roles of osteogenic axes through development including biomechanics, growth factors, and extracellular matrix. The effects of tissue composition and mechanotransduction guiding suture establishment were interrogated both at the medially advancing osteogenic fronts and newly continuous palate mesenchyme. By birth, the mid-palatal suture has adopted characteristics of previously characterized cranial sutures. The suture then undergoes remodeling postnatally in response to multidimensional forces.
Conclusions: We concluded that establishment of the mid-palatal suture depends on a complex, spatiotemporally controlled signalling milieu. These findings advance our understanding of palate and suture developmental biology, especially in the context of maxillofacial orthodontic interventions.