BACKGROUND Palatal expansion treatment has been used to expand the constricted maxillary arch and has become a routine procedure in orthodontic practice over the past decades.However,the long-term stability of expansi...BACKGROUND Palatal expansion treatment has been used to expand the constricted maxillary arch and has become a routine procedure in orthodontic practice over the past decades.However,the long-term stability of expansion in the permanent dentition without a surgical approach is uncertain.CASE SUMMARY We present the case of a 15-year-old boy with Class II malocclusion and constricted arches.The patient was treated with rapid palatal expansion(RPE)followed by a fixed orthodontic appliance.A 7-year follow-up evaluation was performed by analyzing cephalometric radiographs,plaster models,and photographs.The patient’s constricted maxillary and mandibular arches were relived after the expansion treatment.A Class I occlusion and normal arch form were established and maintained in the long-term.CONCLUSION RPE treatment is successful in solving constricted dental arch in the permanent dentition without a surgical approach.Permanent retention and even occlusal contact help prevent long-term relapse.展开更多
Rapid maxillary expansion(RME),as a common treatment for craniomaxillofacial deformity,faces the challenge of high relapse rates and unsatisfactory therapeutic effects.In this study,a standardized Sprague-Dawley(SD)ra...Rapid maxillary expansion(RME),as a common treatment for craniomaxillofacial deformity,faces the challenge of high relapse rates and unsatisfactory therapeutic effects.In this study,a standardized Sprague-Dawley(SD)rat RME model was first established with a modified expander as well as retainer design and optimized anterior maxillary expanding force of 100 g which exerted the most synchronized mobility of mid-palatal suture and incisors.Via the standardized model,the high relapse rate was proven to be attributed to insufficient osteogenesis in expanded suture,requiring long-term retainer wearing in clinical situations.To reduce the relapse rate,mesoporous bioactive glass/fibrin glue(MBG/FG)composite hydrogels were developed for an in situ minimal invasive injection that enhance osteogenesis in the expanded palate.The component of 1 wt%MBG was adopted for enhanced mechanical strength,matched degradation rate and ion dissolution,excellent in vitro biocompatibility and osteoinductivity.Effects of 1%MBG/FG composite hydrogel on osteogenesis in expanded mid-palatal sutures with/without retention were evaluated in the standardized model.The results demonstrated that injection of 1%MBG/FG composite hydrogel significantly promoted bone formation within the expanded mid-palatal suture,inhibited osteoclastogenesis and benefited the balance of bone remodeling towards osteogenesis.Combination of retainer and injectable biomaterial was demonstrated as a promising treatment to reduce relapse rate and enhance osteogenesis after RME.The model establishment and the composite hydrogel development in this article might provide new insight to other craniomaxillofacial deformity treatment and design of bone-repairing biomaterials with higher regenerative efficiency.展开更多
Midpalatal corticotomy-assisted rapid maxillary expansion(MCRME)is a minimally invasive treatment of maxillary transverse deficiency(MTD)in young adults.However,the effect of MCRME on respiratory function still needs ...Midpalatal corticotomy-assisted rapid maxillary expansion(MCRME)is a minimally invasive treatment of maxillary transverse deficiency(MTD)in young adults.However,the effect of MCRME on respiratory function still needs to be determined.In this study,we evaluated the changes in maxillary morphology and the upper airway following MCRME using computational fluid dynamics(CFD).Twenty patients with MTD(8 males,12 females;mean age 20.55 years)had cone-beam computed tomography(CBCT)images taken before and after MCRME.The CBCT data were used to construct a threedimensional(3 D)upper airway model.The upper airway flow characteristics were simulated using CFD,and measurements were made based on the CBCT images and CFD.The results showed that the widths of the palatal bone and nasal cavity,and the intermolar width were increased significantly after MCRME.The volume of the nasal cavity and nasopharynx increased significantly,while there were no obvious changes in the volumes of the oropharynx and hypopharynx.CFD simulation of the upper airway showed that the pressure drop and maximum velocity of the upper airway decreased significantly after treatment.Our results suggest that in these young adults with MTD,increasing the maxillary width,upper airway volume,and quantity of airflow by MCRME substantially improved upper airway ventilation.展开更多
基金Supported by the National Natural Science Foundation of China No.81970909(to Liu DW),No.51903003(to Yu TT)the New Clinical Technology Fund of PKUSS,No.PKUSSNCT-11A07(to Liu DW)Peking University Medicine Seed Fund for Interdisciplinary Research,No.BMU2018MX007(to Liu DW).
文摘BACKGROUND Palatal expansion treatment has been used to expand the constricted maxillary arch and has become a routine procedure in orthodontic practice over the past decades.However,the long-term stability of expansion in the permanent dentition without a surgical approach is uncertain.CASE SUMMARY We present the case of a 15-year-old boy with Class II malocclusion and constricted arches.The patient was treated with rapid palatal expansion(RPE)followed by a fixed orthodontic appliance.A 7-year follow-up evaluation was performed by analyzing cephalometric radiographs,plaster models,and photographs.The patient’s constricted maxillary and mandibular arches were relived after the expansion treatment.A Class I occlusion and normal arch form were established and maintained in the long-term.CONCLUSION RPE treatment is successful in solving constricted dental arch in the permanent dentition without a surgical approach.Permanent retention and even occlusal contact help prevent long-term relapse.
基金the National Natural Science Foundation of China(No.81970973,No.81771036,No.82071097,No.82071096)China Postdoctoral Science Foundation(2020T130422)Shanghai Sailing Program(19YF1425500,19YF1426500).
文摘Rapid maxillary expansion(RME),as a common treatment for craniomaxillofacial deformity,faces the challenge of high relapse rates and unsatisfactory therapeutic effects.In this study,a standardized Sprague-Dawley(SD)rat RME model was first established with a modified expander as well as retainer design and optimized anterior maxillary expanding force of 100 g which exerted the most synchronized mobility of mid-palatal suture and incisors.Via the standardized model,the high relapse rate was proven to be attributed to insufficient osteogenesis in expanded suture,requiring long-term retainer wearing in clinical situations.To reduce the relapse rate,mesoporous bioactive glass/fibrin glue(MBG/FG)composite hydrogels were developed for an in situ minimal invasive injection that enhance osteogenesis in the expanded palate.The component of 1 wt%MBG was adopted for enhanced mechanical strength,matched degradation rate and ion dissolution,excellent in vitro biocompatibility and osteoinductivity.Effects of 1%MBG/FG composite hydrogel on osteogenesis in expanded mid-palatal sutures with/without retention were evaluated in the standardized model.The results demonstrated that injection of 1%MBG/FG composite hydrogel significantly promoted bone formation within the expanded mid-palatal suture,inhibited osteoclastogenesis and benefited the balance of bone remodeling towards osteogenesis.Combination of retainer and injectable biomaterial was demonstrated as a promising treatment to reduce relapse rate and enhance osteogenesis after RME.The model establishment and the composite hydrogel development in this article might provide new insight to other craniomaxillofacial deformity treatment and design of bone-repairing biomaterials with higher regenerative efficiency.
基金supported by the National Natural Science Foundation of China(No.81970978)the Zhejiang Provincial Natural Science Foundation of China(No.LQ18H140004)the Zhejiang Provincial Medical Health&Hygienic Science and Technology Project of China(Nos.2018KY365,2019RC156,and 2020KY449)。
文摘Midpalatal corticotomy-assisted rapid maxillary expansion(MCRME)is a minimally invasive treatment of maxillary transverse deficiency(MTD)in young adults.However,the effect of MCRME on respiratory function still needs to be determined.In this study,we evaluated the changes in maxillary morphology and the upper airway following MCRME using computational fluid dynamics(CFD).Twenty patients with MTD(8 males,12 females;mean age 20.55 years)had cone-beam computed tomography(CBCT)images taken before and after MCRME.The CBCT data were used to construct a threedimensional(3 D)upper airway model.The upper airway flow characteristics were simulated using CFD,and measurements were made based on the CBCT images and CFD.The results showed that the widths of the palatal bone and nasal cavity,and the intermolar width were increased significantly after MCRME.The volume of the nasal cavity and nasopharynx increased significantly,while there were no obvious changes in the volumes of the oropharynx and hypopharynx.CFD simulation of the upper airway showed that the pressure drop and maximum velocity of the upper airway decreased significantly after treatment.Our results suggest that in these young adults with MTD,increasing the maxillary width,upper airway volume,and quantity of airflow by MCRME substantially improved upper airway ventilation.
