Anatomical network modules of the human central nervous-craniofacial skeleton system.

Anatomical network analysis (AnNA) is a systems biological framework based on network theory that enables anatomical structural analysis by incorporating modularity to model structural complexity. The human brain and facial structures exhibit close structural and functional relationships, suggestive of a co-evolved anatomical network. The present study aimed to analyze the human head as a modular entity that comprises the central nervous system, including the brain, spinal cord, and craniofacial skeleton. An AnNA model was built using 39 anatomical nodes from the brain, spinal cord, and craniofacial skeleton. The linkages were identified using peripheral nerve supply and direct contact between structures. The Spinglass algorithm in the igraph software was applied to construct a network and identify the modules of the central nervous system-craniofacial skeleton anatomical network. Two modules were identified. These comprised an anterior module, which included the forebrain, anterior cranial base, and upper-middle face, and a posterior module, which included the midbrain, hindbrain, mandible, and posterior cranium. These findings may reflect the genetic and signaling networks that drive the mosaic central nervous system and craniofacial development and offer important systems biology perspectives for developmental disorders of craniofacial structures.

[Comparison of apical root resorption of maxillary incisors between adolescents and adults after orthodontic treatment].

PURPOSE: To compare apical root resorption of maxillary incisors between adolescents and adults after orthodontic treatment. METHODS: Patients receiving orthodontic treatment in Affiliated Hospital of Chifeng University from May 2014 to August 2016 were enrolled, and divided into two age groups: adolescent group (32) and adult group (36). The included subjects received orthodontic fixed appliance treatment with straight-wire technique combined with Hawley type retainer for one year. After treatment, all patients were followed up for one year. Then the apical root resorption of maxillary incisors was evaluated by cone-beam CT (CBCT) at 4 time points, including pre-treatment (T1), end of treatment (T2), 6 months after treatment (T3), and 12 months after treatment (T4). Data were processed by SPSS 20.0 software package. RESULTS: The external root volume of maxillary central incisor, lateral incisors, mandibular central incisors and mandibular lateral incisors of both sides at T2-T4 was significantly lower than that at T1(P<0.05). There was partial increase in root volume of both groups at T3 and T4, while no significant difference from that at T2 (P>0.05). △root volume T3-T2 and △root volume T4-T3 had no significant difference between the two groups (P>0.05). △root volume T3-T2 in the adolescent group was significantly smaller than that in the adult group (P<0.05). Correlation analysis showed that the △root volumeT1-T2 was significantly positively correlated with age (P<0.05), meanwhile △root volume T3-T2 and △root volume T4-T3 were negatively correlated with age (P<0.05). CONCLUSIONS: Age is an important factor affecting the volume of root after orthodontic treatment. Adolescent patients with Class II division 1 malocclusion have a strong ability of self-healing after orthodontic treatment.