Selecting H-60 PVC foam, four-axis E-glass non-woven fabric and vinyl resin, a type of innovative reinforced sandwich composite as grooved perforation sandwich （GPS） were fabricated by VIMP. The interfacial structur...Selecting H-60 PVC foam, four-axis E-glass non-woven fabric and vinyl resin, a type of innovative reinforced sandwich composite as grooved perforation sandwich （GPS） were fabricated by VIMP. The interfacial structure between the face and core of the sandwich is innovative because of the acuminate grooves in both sides of foam core and the holes perforated along core’s height. The fabrication results show that VIMP is a high-speed and cost-effective manufacturing method. The mechanical properties of the reinforced foam core were tested. The typical flexural failure modes of sandwich specimens were observed. The flexural stiffness and ultimate bearing capacity of sandwich were studied by ordinary sandwich beam theory and finite element method.展开更多
BACKGROUND A palatal radicular groove is an unusual developmental deformity of the tooth,which may serve as a channel linking the periodontal and periapical inflammation,and yet no literature could be obtained analyzi...BACKGROUND A palatal radicular groove is an unusual developmental deformity of the tooth,which may serve as a channel linking the periodontal and periapical inflammation,and yet no literature could be obtained analyzing microbiota within the palatal radicular grooves.CASE SUMMARY Four patients diagnosed with palatal radicular groove and concomitant periodontal-endodontic deformity in permanent maxillary lateral incisors were enrolled in this work.Twelve bacterial samples from 4 patients were collected from different parts of the palatal radicular groove during intentional replantation surgery.Illumina sequencing was performed to analyze the taxonomical composition and microbiome structure inside the palatal grooves,and 1162 operational taxonomic units were obtained.The phyla of Firmicutes and Proteobacteria predominated in most of the samples.An unknown genus from the Bacillaceae family,Lactococcus,and Porphyromonas were the most abundant genera identified.There was no difference in the microbiota richness and diversity in three sections of the groove.CONCLUSION The unique ecological niches inside the palatal grooves harbored bacterial communities that shared some component features of both the endodontic and periodontal infections.The existence of palatal groove may play an interaction bridge between the root apex and tooth cervix and thus impair the outcome of traditional therapeutic methods such as root canal treatment and periodontal management.展开更多
基金Funded by the Special Prophase Project on Basic Research of The Na-tional Department of Scientific and Technology(No. 2008CB617613)the National Natural Science Foundation of China (No. 50978134)the Research Award Fund for Young Teachers of Nanjing University of Technology
文摘Selecting H-60 PVC foam, four-axis E-glass non-woven fabric and vinyl resin, a type of innovative reinforced sandwich composite as grooved perforation sandwich （GPS） were fabricated by VIMP. The interfacial structure between the face and core of the sandwich is innovative because of the acuminate grooves in both sides of foam core and the holes perforated along core’s height. The fabrication results show that VIMP is a high-speed and cost-effective manufacturing method. The mechanical properties of the reinforced foam core were tested. The typical flexural failure modes of sandwich specimens were observed. The flexural stiffness and ultimate bearing capacity of sandwich were studied by ordinary sandwich beam theory and finite element method.
基金Supported by National Natural Science Foundation of China,No.82001037the Research and Develop Program,West China Hospital of Stomatology,Sichuan University,No.RD-02-202007.
文摘BACKGROUND A palatal radicular groove is an unusual developmental deformity of the tooth,which may serve as a channel linking the periodontal and periapical inflammation,and yet no literature could be obtained analyzing microbiota within the palatal radicular grooves.CASE SUMMARY Four patients diagnosed with palatal radicular groove and concomitant periodontal-endodontic deformity in permanent maxillary lateral incisors were enrolled in this work.Twelve bacterial samples from 4 patients were collected from different parts of the palatal radicular groove during intentional replantation surgery.Illumina sequencing was performed to analyze the taxonomical composition and microbiome structure inside the palatal grooves,and 1162 operational taxonomic units were obtained.The phyla of Firmicutes and Proteobacteria predominated in most of the samples.An unknown genus from the Bacillaceae family,Lactococcus,and Porphyromonas were the most abundant genera identified.There was no difference in the microbiota richness and diversity in three sections of the groove.CONCLUSION The unique ecological niches inside the palatal grooves harbored bacterial communities that shared some component features of both the endodontic and periodontal infections.The existence of palatal groove may play an interaction bridge between the root apex and tooth cervix and thus impair the outcome of traditional therapeutic methods such as root canal treatment and periodontal management.
