BACKGROUND Fibrous dysplasia(FD)is a developmental hamartomatous bone disease characterized by a blend of fibrous and osseous entities.Though rarely malignant,the tumor can vary from being small and asymptomatic,to a ...BACKGROUND Fibrous dysplasia(FD)is a developmental hamartomatous bone disease characterized by a blend of fibrous and osseous entities.Though rarely malignant,the tumor can vary from being small and asymptomatic,to a fairly large sized lesion,progressing gradually,compromising occlusion and facial esthetics.Treatment approach depends on the stage of skeletal maturity.It primarily involves surgical management for stabilizing the disease process.Post-surgical comprehensive dental treatment is necessary for restoring form and function of the jaws and teeth.This article describes comprehensive orthodontic management of severe malocclusion in a surgically operated case of FD maxilla.CASE SUMMARY A 19-year female presented with a chief complaint of excessive gingival display when smiling.Dental history included swelling of gums around the upper right front teeth,diagnosed at the age of 15 as FD of the right anterior maxillary segment and treated with surgical recontouring of the dysplastic bone.The clinical and radiological examinations showed adequate post-surgical healing.The surgically treated dysplastic area presented with right canting of the maxillary anterior occlusal plane.The maxillary teeth were torqued palatally,with the root of the right maxillary canine exposed clinically.We discuss sequential management of the associated malocclusion with comprehensive fixed orthodontics,along with special precautions taken to prevent reactivation of the quiescent and healed lesion.CONCLUSION The adequate healing of fibro-dysplastic bone post-surgery must be allowed before initiating orthodontic tooth movement in the dysplastic bone.Periodic follow-ups are needed to monitor stability of occlusion and any relapse of the lesion.展开更多
Producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two...Producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two-dimensional material of group-IV transition metal dichalcogenides. For the first time, we demonstrate a simple and cost-effective method to grow layered belt-like nanocrystals of HfS2 with a notably large interlayer spacing followed by their chemical exfoliation. Various microscopic and spectroscopic techniques confirm that these as-grown crystals exfoliate into single or multiple layers in a few minutes using solvent assisted ultrasonification method in N-cyclohexyl-2- pyrrolidone. The exfoliated nanosheets of HfS2 exhibit an indirect bandgap of 1.3 eV with high stability against surface degradation. Furthermore, we demonstrate that these nanosheets hold potential for electronic applications by fabricating a field-effect transistor based on few-layered HfS2, exhibiting a field-effect mobility of 0.95 cm2/（V.s） with a high on/off current modulation ratio of 10,000 in ambient conditions. The method is scalable and has a potential significance for both academic and industrial purposes.展开更多
文摘BACKGROUND Fibrous dysplasia(FD)is a developmental hamartomatous bone disease characterized by a blend of fibrous and osseous entities.Though rarely malignant,the tumor can vary from being small and asymptomatic,to a fairly large sized lesion,progressing gradually,compromising occlusion and facial esthetics.Treatment approach depends on the stage of skeletal maturity.It primarily involves surgical management for stabilizing the disease process.Post-surgical comprehensive dental treatment is necessary for restoring form and function of the jaws and teeth.This article describes comprehensive orthodontic management of severe malocclusion in a surgically operated case of FD maxilla.CASE SUMMARY A 19-year female presented with a chief complaint of excessive gingival display when smiling.Dental history included swelling of gums around the upper right front teeth,diagnosed at the age of 15 as FD of the right anterior maxillary segment and treated with surgical recontouring of the dysplastic bone.The clinical and radiological examinations showed adequate post-surgical healing.The surgically treated dysplastic area presented with right canting of the maxillary anterior occlusal plane.The maxillary teeth were torqued palatally,with the root of the right maxillary canine exposed clinically.We discuss sequential management of the associated malocclusion with comprehensive fixed orthodontics,along with special precautions taken to prevent reactivation of the quiescent and healed lesion.CONCLUSION The adequate healing of fibro-dysplastic bone post-surgery must be allowed before initiating orthodontic tooth movement in the dysplastic bone.Periodic follow-ups are needed to monitor stability of occlusion and any relapse of the lesion.
文摘Producing environmentally stable monolayers and few-layers of hafnium disulphide （HfS2） with a high yield to reveal its unlocked electronic and optoelectronic applications is still a challenge. HfS2 is a layered two-dimensional material of group-IV transition metal dichalcogenides. For the first time, we demonstrate a simple and cost-effective method to grow layered belt-like nanocrystals of HfS2 with a notably large interlayer spacing followed by their chemical exfoliation. Various microscopic and spectroscopic techniques confirm that these as-grown crystals exfoliate into single or multiple layers in a few minutes using solvent assisted ultrasonification method in N-cyclohexyl-2- pyrrolidone. The exfoliated nanosheets of HfS2 exhibit an indirect bandgap of 1.3 eV with high stability against surface degradation. Furthermore, we demonstrate that these nanosheets hold potential for electronic applications by fabricating a field-effect transistor based on few-layered HfS2, exhibiting a field-effect mobility of 0.95 cm2/（V.s） with a high on/off current modulation ratio of 10,000 in ambient conditions. The method is scalable and has a potential significance for both academic and industrial purposes.
