Moore Jacob C, Husain Tooba S, Huston Lila A, Steele Ashley T, Organ Jason M, Gonzales Lauren A, Menegaz Rachel A, Handler Emma K
Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA.
Edward Via College of Osteopathic Medicine, Monroe, Louisiana, USA.
Anat Rec (Hoboken). 2024 Mar;307(3):600-610. doi: 10.1002/ar.25306. Epub 2023 Aug 28.
Osteogenesis imperfecta (OI), a disorder of type I collagen, causes skeletal deformities as well as defects in dental tissues, which lead to increased enamel wear and smaller teeth with shorter roots. Mice with OI exhibit similar microstructural dentin changes, including reduced dentin tubule density and dentin cross-sectional area. However, the effects of these mutations on gross dental morphology and dental tissue volumes have never been characterized in the osteogenesis imperfecta murine (OIM) mouse model. Here we compare mineralized dental tissue measurements of OIM mice and unaffected wild type (WT) littermates at the juvenile and adult stages. The maxillary and mandibular incisors and first molars were isolated from microCT scans, and tissue volumes and root length were measured. OIM mice have smaller teeth with shorter roots relative to WT controls. Maxillary incisor volumes differed significantly between OIM and WT mice at both the juvenile and young adult stage, perhaps due to shortening of the maxilla itself in OIM mice. Additionally, adult OIM mice have significantly less crown enamel volume than do juveniles, potentially due to loss through wear. Thus, OIM mice demonstrate a dental phenotype similar to humans with OI, with decreased tooth size, decreased root length, and accelerated enamel wear. Further investigation of dental development in the OIM mouse may have important implications for the development and treatment of dental issues in OI patients.
成骨不全症（OI）是一种I型胶原蛋白紊乱疾病，会导致骨骼畸形以及牙齿组织缺陷，进而导致牙釉质磨损增加以及牙齿变小、牙根变短。患有OI的小鼠表现出类似的牙本质微观结构变化，包括牙本质小管密度降低和牙本质横截面积减小。然而，在成骨不全症小鼠（OIM）模型中，这些突变对牙齿总体形态和牙齿组织体积的影响尚未得到表征。在这里，我们比较了幼年和成年阶段OIM小鼠与未受影响的野生型（WT）同窝小鼠矿化牙齿组织的测量结果。从微型计算机断层扫描（microCT）中分离出上颌和下颌切牙以及第一磨牙，并测量组织体积和牙根长度。与WT对照组相比，OIM小鼠的牙齿更小，牙根更短。在幼年和年轻成年阶段，OIM小鼠和WT小鼠的上颌切牙体积存在显著差异，这可能是由于OIM小鼠上颌本身缩短所致。此外，成年OIM小鼠的牙冠釉质体积明显少于幼年小鼠，这可能是由于磨损导致的损失。因此，OIM小鼠表现出与患有OI的人类相似的牙齿表型，即牙齿尺寸减小、牙根长度减小和牙釉质磨损加速。对OIM小鼠牙齿发育的进一步研究可能对OI患者牙齿问题的发展和治疗具有重要意义。
