Influence of differences in the hardness and calcium content of diets on the growth of craniofacial bone in rats

• Published in: The Angle orthodontist 2015-11, Vol.85 (6), p.969-979
• Main Authors: Goto, Shota, Fujita, Yuko, Hotta, Maika, Sugiyama, Ayako, Maki, Kenshi
• Format: Article
• Language: English
• Subjects: Animals; Bone and Bones - physiology; Calcium - administration & dosage; Cephalometry; Dentistry; Diet - methods; Hardness; Histocytochemistry; Male; Original; Rats; Skull - anatomy & histology; Skull - growth & development; Skull - physiology; X-Ray Microtomography
• ISSN: 0003-3219; 1945-7103
• DOI: 10.2319/102214-765.1

To examine the effects of a soft diet and a low-calcium diet on the craniofacial growth and bone architectures of the maxilla and mandible. Male rats (n  =  20, 3 weeks old) were divided into four groups. Ten rats were given a normal-calcium diet, and the other rats were given a low-calcium diet. Each group was then divided into two subgroups, which were fed a hard or a soft diet. After 4 weeks, craniofacial growth and architecture in maxillary and mandibular bone were analyzed using cephalometry, micro-computed tomography, and histopathology. The low-calcium diet had no effect on serum calcium levels. The low-calcium diet had the greatest effect on craniofacial bone growth, while the soft diet affected the growth of several bone sites that are attached to the masseter muscle. A low-calcium diet resulted in the deterioration of the connectivity of the trabeculae in the furcation region of the maxillary and mandibular first molar, while a soft diet resulted in the diffuse disappearance of trabeculae in the central part of the furcation regions. In the midpalatal suture, a low-calcium diet resulted in inhibition of cartilaginous ossification, although the midpalatal suture had a normal cartilaginous structure. A soft diet resulted in narrower cartilage cell layers in the midpalatal suture. We demonstrated that a low-calcium diet and a soft diet resulted in a deterioration of bone structures in both the maxilla and in the mandible; however, the mechanisms underlying these effects differed between diets.