The aim of this study is to investigate the influence of different posts on the fracture mechanics of endodontically-treated teeth with open apex. Forty-eight human maxillary anterior teeth were collected, and the roo...The aim of this study is to investigate the influence of different posts on the fracture mechanics of endodontically-treated teeth with open apex. Forty-eight human maxillary anterior teeth were collected, and the root was transversely sectioned 12 mm under the cementoenamal junction （CEJ）. These samples were then randomly divided into two groups, i.e., minor diameter open apex root （group A） and major diameter open apex root （group B）, with mineral trioxide aggregate （MTA） placed into the apical 4 mm in the root canals. Subsequently, both groups were respectively further divided into three subgroups as follows： fiber-post （subgroup 1）, metal post （subgroup 2） and non-post （subgroup 3） group. Teeth were restored with a composite resin crown and tested by using a universal testing machine at the rate of 1 mm/min cross-head. Values of the maximum fracture resistance and failure patterns were recorded and compared among all subgroups. In addition, the changes of MTA properties were carefully examined via X-ray photography. Our results indicate that （1） In group A, the mean value of fracture resistance for teeth restored with fiber posts were statistically higher than that with either metal post or non-post; （2） In group B, there was no statistically significant difference in the mean value of fracture resistance among three subgroups; （3） No statistical significance in the mean value of fracture resistance was found between group A and group B; （4） The failure modes of most samples （58%） were irreparable; （5） MTA in two teeth developed cracks after loading tests. In conclusion, endodontically-treated teeth restored with fiber posts are more resistant to fracture than those restored with either metal posts or non-post, and most of the fracture modes are catastrophic in nature.展开更多
The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each case.The main objec...The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each case.The main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and techniques.Future research on apexification should focus on how to treat open apices with wide periapical lesions without surgery.Previously,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more predictable.Another reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.展开更多
One-step apexification using mineral trioxide aggregate(MTA) has been reported as an alternative treatment modality with more benefits than the use of long-term calcium hydroxide for teeth with open apex.However,ortho...One-step apexification using mineral trioxide aggregate(MTA) has been reported as an alternative treatment modality with more benefits than the use of long-term calcium hydroxide for teeth with open apex.However,orthograde placement of MTA is a challenging procedure in terms of length control.This case series describes the sequence of events following apical extrusion of MTA into the periapical area during a one-step apexification procedure for maxillary central incisor with an infected immature apex.Detailed long-term observation revealed complete resolution of the periapical radiolucent lesion around the extruded MTA.These cases revealed that direct contact with MTA had no negative effects on healing of the periapical tissues.However,intentional MTA overfilling into the periapical lesion is not to be recommended.展开更多
BACKGROUND Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful app...BACKGROUND Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful approach, i.e., we should consider the shape and depth of the concave folding, the condition of the original pulp, and the growth stage of the root formation. CASE SUMMARY A 9-year-old girl complained of severe pain of the right maxillary incisor (tooth 12) when chewing for two weeks. Following clinical and radiographic examinations, Oehlers type III DI of tooth 12, with an immature open apical foramen and a symptomatic periapical pathosis, was diagnosed. Cone-beam computed tomography verified the specific spatial and stereoscopic data regarding the communication between the main root canal and pseudo root canal of the involved tooth. After removing the source of infection, a mineral trioxide aggregate was selected to fill and seal the pseudo root canal;additionally, pulp capping of the main canal was performed through the interconnections between the root canals in the middle segment to preserve pulp vitality and enable continual root formation and eventual root apex closure. CONCLUSION We propose to conduct main root canal pulp capping for DI with communication between the main and pseudo root canals.展开更多
基金supported by a grant from a program of research and development of Hubei Province (No. 2008-BCC 001)
文摘The aim of this study is to investigate the influence of different posts on the fracture mechanics of endodontically-treated teeth with open apex. Forty-eight human maxillary anterior teeth were collected, and the root was transversely sectioned 12 mm under the cementoenamal junction （CEJ）. These samples were then randomly divided into two groups, i.e., minor diameter open apex root （group A） and major diameter open apex root （group B）, with mineral trioxide aggregate （MTA） placed into the apical 4 mm in the root canals. Subsequently, both groups were respectively further divided into three subgroups as follows： fiber-post （subgroup 1）, metal post （subgroup 2） and non-post （subgroup 3） group. Teeth were restored with a composite resin crown and tested by using a universal testing machine at the rate of 1 mm/min cross-head. Values of the maximum fracture resistance and failure patterns were recorded and compared among all subgroups. In addition, the changes of MTA properties were carefully examined via X-ray photography. Our results indicate that （1） In group A, the mean value of fracture resistance for teeth restored with fiber posts were statistically higher than that with either metal post or non-post; （2） In group B, there was no statistically significant difference in the mean value of fracture resistance among three subgroups; （3） No statistical significance in the mean value of fracture resistance was found between group A and group B; （4） The failure modes of most samples （58%） were irreparable; （5） MTA in two teeth developed cracks after loading tests. In conclusion, endodontically-treated teeth restored with fiber posts are more resistant to fracture than those restored with either metal posts or non-post, and most of the fracture modes are catastrophic in nature.
文摘The success rate of apexification is primarily determined by multiple factors,including the material used,the size of the open apex compared to the length of the root,and the technique used in each case.The main objective of this review was to provide an update on the present management of open apex to identify factors and circumstances that may influence the success of apexification using different materials and techniques.Future research on apexification should focus on how to treat open apices with wide periapical lesions without surgery.Previously,the predictability of these parameters with non-surgical procedures was uncertain,but now,with the use of a dental operating microscope,it has become more predictable.Another reason could be that extra visits are no longer required due to major advances in the armamentarium and materials used for apexification.
基金supported by the National Research Foundation(NRF) of Koreafunded by the Ministry of Education,Science and Technology(MEST) (No.2011-0014231,Dr.Seok-Wood Chang),Korea
文摘One-step apexification using mineral trioxide aggregate(MTA) has been reported as an alternative treatment modality with more benefits than the use of long-term calcium hydroxide for teeth with open apex.However,orthograde placement of MTA is a challenging procedure in terms of length control.This case series describes the sequence of events following apical extrusion of MTA into the periapical area during a one-step apexification procedure for maxillary central incisor with an infected immature apex.Detailed long-term observation revealed complete resolution of the periapical radiolucent lesion around the extruded MTA.These cases revealed that direct contact with MTA had no negative effects on healing of the periapical tissues.However,intentional MTA overfilling into the periapical lesion is not to be recommended.
基金Supported by a grant from the Kaohsiung Medical University,No.KMUH106-6M52
文摘BACKGROUND Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful approach, i.e., we should consider the shape and depth of the concave folding, the condition of the original pulp, and the growth stage of the root formation. CASE SUMMARY A 9-year-old girl complained of severe pain of the right maxillary incisor (tooth 12) when chewing for two weeks. Following clinical and radiographic examinations, Oehlers type III DI of tooth 12, with an immature open apical foramen and a symptomatic periapical pathosis, was diagnosed. Cone-beam computed tomography verified the specific spatial and stereoscopic data regarding the communication between the main root canal and pseudo root canal of the involved tooth. After removing the source of infection, a mineral trioxide aggregate was selected to fill and seal the pseudo root canal;additionally, pulp capping of the main canal was performed through the interconnections between the root canals in the middle segment to preserve pulp vitality and enable continual root formation and eventual root apex closure. CONCLUSION We propose to conduct main root canal pulp capping for DI with communication between the main and pseudo root canals.
