During dental examinations and treatments,many dentists are using magni-fication to improve their vision.The dental operating microscope serves as the most effective tool for this purpose,enhancing the quality,longevi...During dental examinations and treatments,many dentists are using magni-fication to improve their vision.The dental operating microscope serves as the most effective tool for this purpose,enhancing the quality,longevity,and outcome of clinical work.This review will explore the latest research and data on the importance of magnification devices in dentistry,including diagnostic methods,treatment options and ergonomics in specialities such as restorative dentistry,endodontics,pedodontics,periodontics,and prosthodontics.This review aims to provide insights into the optimal magnification for different clinical situations,the specific benefits of dental operating microscopes for each dental branch,and their limitations.展开更多
Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the si...Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the simple intra-oral periapical X-rays, advanced imaging techniques like computed tomography, cone beam computed tomography, magnetic resonance imaging and ultrasound have also found place in modern dentistry. Changing from analogue to digital radiography has not only made the process simpler and faster but also made image storage, manipulation(brightness/contrast, image cropping, etc.) and retrieval easier. The three-dimensional imaging has made the complex cranio-facial structures more accessible for examination and early and accurate diagnosis of deep seated lesions. This paper is to review current advances in imaging technology and their uses in different disciplines of dentistry.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
Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate a...Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate anatomy of the root canal system,instrument-related factors,and instrumentation techniques.Instrument separation can hinder thorough cleaning,shaping,and obturation of the root canal,posing challenges to successful treatment outcomes.Although retrieval of separated instrument is often feasible,it carries risks including perforation,excessive removal of tooth structure and root fractures.Effective management of separated instruments requires a comprehensive understanding of the contributing factors,meticulous preoperative assessment,and precise evaluation of the retrieval difficulty.The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes.The current manuscript provides a framework for understanding the causes,risk factors,and clinical management principles of instrument separation.By integrating effective strategies,endodontists can enhance decision-making,improve endodontic treatment success and ensure the preservation of natural dentition.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
BACKGROUND The management of immature permanent teeth with open apices in pediatric patients presents unique challenges,particularly in cases of nonvital pulp.Modern advancements in materials and techniques have signi...BACKGROUND The management of immature permanent teeth with open apices in pediatric patients presents unique challenges,particularly in cases of nonvital pulp.Modern advancements in materials and techniques have significantly improved the predictability and success of apexification procedures.In this case,a 16-yearold patient presented with an immature necrotic tooth requiring apexification.Contemporary approaches incorporate calcium silicate-based materials such as mineral trioxide aggregate(MTA),Biodentine,and bioceramic putty,along with bioceramic sealers and enhanced canal cleaning including internal heating and ultrasonic activation with sodium hypochlorite(NaOCl)for disinfection,and sealing.Additionally,magnification tools such as dental operating microscopes ensure precise visualization for accurate material placement,while a micro-apical placement(MAP)system guarantees void-free MTA delivery.These advancements improve procedural outcomes and minimize the risk of iatrogenic errors,making apexification a more predictable and reliable treatment option in pediatric patients with immature teeth.CASE SUMMARY A 16-year-old patient presented with a nonvital maxillary central incisor with an open apex,secondary to trauma.Due to the lack of apical closure,traditional root canal obturation was not feasible.Apexification was chosen as the treatment modality to induce the formation of a calcified apical barrier,allowing for proper root canal sealing.Historically,calcium hydroxide was the material of choice for apexification,requiring multiple visits and prolonged treatment duration.However,the introduction of bioceramic materials such as MTA has revolutionized the procedure,offering superior outcomes with reduced treatment time.In this case,the apexification procedure involved thorough canal disinfection using NaOCl,enhanced by internal heating,ultrasonic activation,and double-sided vented needle irrigation.Under the dental operating microscope,MTA was precisely placed at the apex using a MAP system,ensuring a dense,void-free apical barrier.The remaining canal space was subsequently sealed with a bioceramic sealer to promote long-term stability and healing.CONCLUSION This case highlights the effectiveness of a modern approach for apexification in a pediatric patient.The use of advanced materials and techniques facilitated the formation of a stable apical barrier,ensuring long-term tooth retention and function.By incorporating precise irrigation protocols,internal heating,ultrasonic activation,and magnification tools,the treatment achieved thorough disinfection and optimal material placement.These advancements make apexification a predictable and reliable treatment option for young patients with immature necrotic teeth,preserving their natural dentition and preventing future complications.展开更多
BACKGROUND The primary issue in managing edentulous patients is the severely resorbed mandibular ridge,particularly in older individuals with diminished adaptive capacities.This compromised situation leads to the fabr...BACKGROUND The primary issue in managing edentulous patients is the severely resorbed mandibular ridge,particularly in older individuals with diminished adaptive capacities.This compromised situation leads to the fabrication of inadequate dentures that lack retention and stability,potentially causing psychosocial issues.AIM To determine the difference in retentive capacity between three attachment systems in implant-retained overdentures.METHODS Three edentulous mandibular models were fabricated using heat-cured polymethacrylate resin,with two implant replicas placed in the intra-foraminal region of each model.30 acrylic resin mandibular overdentures were fabricated with provisions for three different overdenture attachment systems:A prefabricated ball/O-ring attachment,a locator attachment system,and an equator attachment system.Each model was subjected to 15000 pulls using a universal testing machine to remove the overdenture from the acrylic model and the force data were recorded.RESULTS The ball/O-ring attachment system demonstrated superior retentive capacity for 15 years,while the locator and equator attachment systems maintained excellent retentive capacity for 5 years.CONCLUSION The ball/O-ring attachment system outperformed better than the other two attachment systems regarding retentive capacity.The locator and equator attachment systems presented sufficient retentive abilities until 15000 cycles.After 7500 cycles,significant differences in retentive force between the systems evolved.展开更多
BACKGROUND Advanced materials and techniques are used to successfully manage the apexification of immature teeth with open apices.The use of mineral trioxide aggregate(MTA),bioceramic sealers,and sodium hypochlorite(N...BACKGROUND Advanced materials and techniques are used to successfully manage the apexification of immature teeth with open apices.The use of mineral trioxide aggregate(MTA),bioceramic sealers,and sodium hypochlorite(NaOCl),combined with internal heating and ultrasonic activation,ensures that canals are cleaned,disinfected,and sealed properly.Magnification devices,such as dental operating microscopes(DOM),provide precise visualization for accurate material placement,while the micro apical placement system ensures void-free MTA delivery.This modern approach improves procedural outcomes,lowers iatrogenic errors,and increases long-term success in apexification,making it a dependable and predictable treatment option for immature teeth.CASE SUMMARY Apexification is a regenerative endodontic procedure that involves creating a calcified barrier at the apex of a nonvital tooth with an open apex.This technique is commonly used in immature teeth with necrotic pulps to ensure proper root canal sealing.Traditionally,calcium hydroxide was the preferred material,but advances have introduced bioceramic cements like MTA or Biodentine,which provide superior results with less treatment time.Apexification not only helps to maintain the tooth's structural integrity but also prevents further complications,making it an important procedure in such cases.CONCLUSION This case demonstrates the effectiveness of integrating advanced materials,precise irrigation protocols,and magnification tools in the apexification of immature teeth with open apices.The use of MTA created a stable apical barrier,while bioceramic sealers enhanced the seal and promoted long-term healing.NaOCl with internal heating,ultrasonic activation,and double-sided vented needles ensured thorough irrigation and disinfection,especially in complex canal anatomy.展开更多
During restorative dental procedures,complete control over the operative site is critical for patient comfort,safety,and the operator’s access and visibility.The success of a fixed prosthesis depends on accurate impr...During restorative dental procedures,complete control over the operative site is critical for patient comfort,safety,and the operator’s access and visibility.The success of a fixed prosthesis depends on accurate impression making of the prepared finish lines on the abutment teeth.To optimise long-term outcomes for the fixed restoration,gingival retraction techniques should be used to decrease the marginal discrepancy among the restoration and the prepared abutment.Accurate marginal positioning of the restoration along the prepared finish line of the abutment is essential for therapeutic,preventive,and aesthetic purposes.展开更多
Pulpotomy,which belongs to vital pulp therapy,has become a strategy for managing pulpitis in recent decades.This minimally invasive treatment reflects the recognition of preserving healthy dental pulp and optimizing l...Pulpotomy,which belongs to vital pulp therapy,has become a strategy for managing pulpitis in recent decades.This minimally invasive treatment reflects the recognition of preserving healthy dental pulp and optimizing long-term patient-centered outcomes.Pulpotomy is categorized into partial pulpotomy(PP),the removal of a partial segment of the coronal pulp tissue,and full pulpotomy(FP),the removal of whole coronal pulp,which is followed by applying the biomaterials onto the remaining pulp tissue and ultimately restoring the tooth.Procedural decisions for the amount of pulp tissue removal or retention depend on the diagnostic of pulp vitality,the overall treatment plan,the patient’s general health status,and pulp inflammation reassessment during operation.This statement represents the consensus of an expert committee convened by the Society of Cariology and Endodontics,Chinese Stomatological Association.It addresses the current evidence to support the application of pulpotomy as a potential alternative to root canal treatment(RCT)on mature permanent teeth with pulpitis from a biological basis,the development of capping biomaterial,and the diagnostic considerations to evidence-based medicine.This expert statement intends to provide a clinical protocol of pulpotomy,which facilitates practitioners in choosing the optimal procedure and increasing their confidence in this rapidly evolving field.展开更多
Apical microsurgery is accurate and minimally invasive,produces few complications,and has a success rate of more than 90%.However,due to the lack of awareness and understanding of apical microsurgery by dental general...Apical microsurgery is accurate and minimally invasive,produces few complications,and has a success rate of more than 90%.However,due to the lack of awareness and understanding of apical microsurgery by dental general practitioners and even endodontists,many clinical problems remain to be overcome.The consensus has gathered well-known domestic experts to hold a series of special discussions and reached the consensus.This document specifies the indications,contraindications,preoperative preparations,operational procedures,complication prevention measures,and efficacy evaluation of apical microsurgery and is applicable to dentists who perform apical microsurgery after systematic training.展开更多
Intentional tooth replantation(ITR)is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions.ITR is defined as the deliberate extraction...Intentional tooth replantation(ITR)is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions.ITR is defined as the deliberate extraction of a tooth;evaluation of the root surface,endodontic manipulation,and repair;and placement of the tooth back into its original socket.Case reports,case series,cohort studies,and randomized controlled trials have demonstrated the efficacy of ITR in the retention of natural teeth that are untreatable or difficult to manage with root canal treatment or endodontic microsurgery.However,variations in clinical protocols for ITR exist due to the empirical nature of the original protocols and rapid advancements in the field of oral biology and dental materials.This heterogeneity in protocols may cause confusion among dental practitioners;therefore,guidelines and considerations for ITR should be explicated.This expert consensus discusses the biological foundation of ITR,the available clinical protocols and current status of ITR in treating teeth with refractory apical periodontitis or anatomical aberration,and the main complications of this treatment,aiming to refine the clinical management of ITR in accordance with the progress of basic research and clinical studies;the findings suggest that ITR may become a more consistent evidence-based option in dental treatment.展开更多
Mesenchymal stem cells(MSCs)are considered as an attractive tool for tissue regeneration and possess a strong immunomodulatory ability.Dental tissuederived MSCs can be isolated from different sources,such as the denta...Mesenchymal stem cells(MSCs)are considered as an attractive tool for tissue regeneration and possess a strong immunomodulatory ability.Dental tissuederived MSCs can be isolated from different sources,such as the dental pulp,periodontal ligament,deciduous teeth,apical papilla,dental follicles and gingiva.According to numerous in vitro studies,the effect of dental MSCs on immune cells might depend on several factors,such as the experimental setting,MSC tissue source and type of immune cell preparation.Most studies have shown that the immunomodulatory activity of dental MSCs is strongly upregulated by activated immune cells.MSCs exert mostly immunosuppressive effects,leading to the dampening of immune cell activation.Thus,the reciprocal interaction between dental MSCs and immune cells represents an elegant mechanism that potentially contributes to tissue homeostasis and inflammatory disease progression.Although the immunomodulatory potential of dental MSCs has been extensively investigated in vitro,its role in vivo remains obscure.A few studies have reported that the MSCs isolated from inflamed dental tissues have a compromised immunomodulatory ability.Moreover,the expression of some immunomodulatory proteins is enhanced in periodontal disease and even shows some correlation with disease severity.MSC-based immunomodulation may play an essential role in the regeneration of different dental tissues.Therefore,immunomodulation-based strategies may be a very promising tool in regenerative dentistry.展开更多
Revascularization of immature necrotic teeth is a reliable treatment alternative to conventional apexogenesis or apexification. In case 1, a 12-year-old boy had his necrotic, immature mandibular left second premolar t...Revascularization of immature necrotic teeth is a reliable treatment alternative to conventional apexogenesis or apexification. In case 1, a 12-year-old boy had his necrotic, immature mandibular left second premolar treated with a revascularization technique. At a 24-month follow-up, periapical radiolucency had disappeared and thickening of the root wall was observed. In cases 2 and 3, a lO-year-old boy had his necrotic, immature, bilateral mandibular second premolars treated with the same modality. At 48-month （in case 2） and 42-month （in case 3） follow-ups, loss of periapical radiolucencies and increases in the root wall thickness were also observed.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
Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester(CAPE), which is a potent inducer of heme oxygenase 1(HO1), is a central active component of propolis, and ...Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester(CAPE), which is a potent inducer of heme oxygenase 1(HO1), is a central active component of propolis, and the application of propolis improves periodontal status in diabetic patients. Here, primary murine macrophages were exposed to CAPE. Target gene expression was assessed by whole-genome microarray, RT-PCR and Western blotting. The antioxidative and anti-inflammatory activities of CAPE were examined by exposure of the cells to hydrogen peroxide, saliva and periodontal pathogens. The involvement of HO1 was investigated with the HO1 inhibitor tin protoporphyrin(SnPP) and knockout mice for Nrf2, which is a transcription factor for detoxifying enzymes. CAPE increased HO1 and other heat shock proteins in murine macrophages. A p38 MAPK inhibitor and Nrf2 knockout attenuated CAPE-induced HO1 expression in macrophages. CAPE exerted strong antioxidative activity. Additionally, CAPE reduced the inflammatory response to saliva and periodontal pathogens. Blocking HO1 decreased the antioxidative activity and attenuated the anti-inflammatory activity of CAPE. In conclusion, CAPE exerted its antioxidative effects through the Nrf2-mediated HO1 pathway and its anti-inflammatory effects through NF-κB inhibition. However, preclinical models evaluating the use of CAPE in periodontal inflammation are necessary in future studies.展开更多
A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine.The aim of this study was to compare the antimicrobial activity of 1%alexidine with that...A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine.The aim of this study was to compare the antimicrobial activity of 1%alexidine with that of 2%chlorhexidine using Enterococcus faecalis-infected dentin blocks.Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each.E.faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2%chlorhexidine or 1%alexidine solutions for 5 and 10 min,respectively.Sterile saline was used as a control.The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope.Significantly fewer bacteria were observed in the 2%chlorhexidine-or 1%alexidine-soaked groups than in the control group(P<0.05).However,there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups(P>0.05).Ruptured or antiseptic-attached bacteria were more frequently observed in the 10-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups.In conclusion,10-min soaking with 1%alexidine or 2%chlorhexidine can be effective against E.faecalis infection.展开更多
All-trans retinoic acid（ATRA） inhibits matrix metalloproteinase（MMP）-2 and MMP-9 in synovial fibroblasts, skin fibroblasts,bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leuke...All-trans retinoic acid（ATRA） inhibits matrix metalloproteinase（MMP）-2 and MMP-9 in synovial fibroblasts, skin fibroblasts,bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells（HDPCs）. The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA（mRNA） expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction（PCR）, respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol？L21ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs,which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.展开更多
Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved ...Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone） with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed（P〈0.05） by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file（P〈0.001）, while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups（P〉0.05）. The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation（P〈0.05）. In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.展开更多
文摘During dental examinations and treatments,many dentists are using magni-fication to improve their vision.The dental operating microscope serves as the most effective tool for this purpose,enhancing the quality,longevity,and outcome of clinical work.This review will explore the latest research and data on the importance of magnification devices in dentistry,including diagnostic methods,treatment options and ergonomics in specialities such as restorative dentistry,endodontics,pedodontics,periodontics,and prosthodontics.This review aims to provide insights into the optimal magnification for different clinical situations,the specific benefits of dental operating microscopes for each dental branch,and their limitations.
文摘Dentistry has witnessed tremendous advances in all its branches over the past three decades. With these advances, the need for more precise diagnostic tools,specially imaging methods, have become mandatory.From the simple intra-oral periapical X-rays, advanced imaging techniques like computed tomography, cone beam computed tomography, magnetic resonance imaging and ultrasound have also found place in modern dentistry. Changing from analogue to digital radiography has not only made the process simpler and faster but also made image storage, manipulation(brightness/contrast, image cropping, etc.) and retrieval easier. The three-dimensional imaging has made the complex cranio-facial structures more accessible for examination and early and accurate diagnosis of deep seated lesions. This paper is to review current advances in imaging technology and their uses in different disciplines of dentistry.
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.
文摘Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate anatomy of the root canal system,instrument-related factors,and instrumentation techniques.Instrument separation can hinder thorough cleaning,shaping,and obturation of the root canal,posing challenges to successful treatment outcomes.Although retrieval of separated instrument is often feasible,it carries risks including perforation,excessive removal of tooth structure and root fractures.Effective management of separated instruments requires a comprehensive understanding of the contributing factors,meticulous preoperative assessment,and precise evaluation of the retrieval difficulty.The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes.The current manuscript provides a framework for understanding the causes,risk factors,and clinical management principles of instrument separation.By integrating effective strategies,endodontists can enhance decision-making,improve endodontic treatment success and ensure the preservation of natural dentition.
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.
文摘BACKGROUND The management of immature permanent teeth with open apices in pediatric patients presents unique challenges,particularly in cases of nonvital pulp.Modern advancements in materials and techniques have significantly improved the predictability and success of apexification procedures.In this case,a 16-yearold patient presented with an immature necrotic tooth requiring apexification.Contemporary approaches incorporate calcium silicate-based materials such as mineral trioxide aggregate(MTA),Biodentine,and bioceramic putty,along with bioceramic sealers and enhanced canal cleaning including internal heating and ultrasonic activation with sodium hypochlorite(NaOCl)for disinfection,and sealing.Additionally,magnification tools such as dental operating microscopes ensure precise visualization for accurate material placement,while a micro-apical placement(MAP)system guarantees void-free MTA delivery.These advancements improve procedural outcomes and minimize the risk of iatrogenic errors,making apexification a more predictable and reliable treatment option in pediatric patients with immature teeth.CASE SUMMARY A 16-year-old patient presented with a nonvital maxillary central incisor with an open apex,secondary to trauma.Due to the lack of apical closure,traditional root canal obturation was not feasible.Apexification was chosen as the treatment modality to induce the formation of a calcified apical barrier,allowing for proper root canal sealing.Historically,calcium hydroxide was the material of choice for apexification,requiring multiple visits and prolonged treatment duration.However,the introduction of bioceramic materials such as MTA has revolutionized the procedure,offering superior outcomes with reduced treatment time.In this case,the apexification procedure involved thorough canal disinfection using NaOCl,enhanced by internal heating,ultrasonic activation,and double-sided vented needle irrigation.Under the dental operating microscope,MTA was precisely placed at the apex using a MAP system,ensuring a dense,void-free apical barrier.The remaining canal space was subsequently sealed with a bioceramic sealer to promote long-term stability and healing.CONCLUSION This case highlights the effectiveness of a modern approach for apexification in a pediatric patient.The use of advanced materials and techniques facilitated the formation of a stable apical barrier,ensuring long-term tooth retention and function.By incorporating precise irrigation protocols,internal heating,ultrasonic activation,and magnification tools,the treatment achieved thorough disinfection and optimal material placement.These advancements make apexification a predictable and reliable treatment option for young patients with immature necrotic teeth,preserving their natural dentition and preventing future complications.
文摘BACKGROUND The primary issue in managing edentulous patients is the severely resorbed mandibular ridge,particularly in older individuals with diminished adaptive capacities.This compromised situation leads to the fabrication of inadequate dentures that lack retention and stability,potentially causing psychosocial issues.AIM To determine the difference in retentive capacity between three attachment systems in implant-retained overdentures.METHODS Three edentulous mandibular models were fabricated using heat-cured polymethacrylate resin,with two implant replicas placed in the intra-foraminal region of each model.30 acrylic resin mandibular overdentures were fabricated with provisions for three different overdenture attachment systems:A prefabricated ball/O-ring attachment,a locator attachment system,and an equator attachment system.Each model was subjected to 15000 pulls using a universal testing machine to remove the overdenture from the acrylic model and the force data were recorded.RESULTS The ball/O-ring attachment system demonstrated superior retentive capacity for 15 years,while the locator and equator attachment systems maintained excellent retentive capacity for 5 years.CONCLUSION The ball/O-ring attachment system outperformed better than the other two attachment systems regarding retentive capacity.The locator and equator attachment systems presented sufficient retentive abilities until 15000 cycles.After 7500 cycles,significant differences in retentive force between the systems evolved.
文摘BACKGROUND Advanced materials and techniques are used to successfully manage the apexification of immature teeth with open apices.The use of mineral trioxide aggregate(MTA),bioceramic sealers,and sodium hypochlorite(NaOCl),combined with internal heating and ultrasonic activation,ensures that canals are cleaned,disinfected,and sealed properly.Magnification devices,such as dental operating microscopes(DOM),provide precise visualization for accurate material placement,while the micro apical placement system ensures void-free MTA delivery.This modern approach improves procedural outcomes,lowers iatrogenic errors,and increases long-term success in apexification,making it a dependable and predictable treatment option for immature teeth.CASE SUMMARY Apexification is a regenerative endodontic procedure that involves creating a calcified barrier at the apex of a nonvital tooth with an open apex.This technique is commonly used in immature teeth with necrotic pulps to ensure proper root canal sealing.Traditionally,calcium hydroxide was the preferred material,but advances have introduced bioceramic cements like MTA or Biodentine,which provide superior results with less treatment time.Apexification not only helps to maintain the tooth's structural integrity but also prevents further complications,making it an important procedure in such cases.CONCLUSION This case demonstrates the effectiveness of integrating advanced materials,precise irrigation protocols,and magnification tools in the apexification of immature teeth with open apices.The use of MTA created a stable apical barrier,while bioceramic sealers enhanced the seal and promoted long-term healing.NaOCl with internal heating,ultrasonic activation,and double-sided vented needles ensured thorough irrigation and disinfection,especially in complex canal anatomy.
文摘During restorative dental procedures,complete control over the operative site is critical for patient comfort,safety,and the operator’s access and visibility.The success of a fixed prosthesis depends on accurate impression making of the prepared finish lines on the abutment teeth.To optimise long-term outcomes for the fixed restoration,gingival retraction techniques should be used to decrease the marginal discrepancy among the restoration and the prepared abutment.Accurate marginal positioning of the restoration along the prepared finish line of the abutment is essential for therapeutic,preventive,and aesthetic purposes.
基金supported by the National Natural Science Foundation of China(82170941 and 82370948 to Lu Zhang,82071110 and 82230029 to Zhi Chen)the National Key R&D Program of China(2018YFC1105100)。
文摘Pulpotomy,which belongs to vital pulp therapy,has become a strategy for managing pulpitis in recent decades.This minimally invasive treatment reflects the recognition of preserving healthy dental pulp and optimizing long-term patient-centered outcomes.Pulpotomy is categorized into partial pulpotomy(PP),the removal of a partial segment of the coronal pulp tissue,and full pulpotomy(FP),the removal of whole coronal pulp,which is followed by applying the biomaterials onto the remaining pulp tissue and ultimately restoring the tooth.Procedural decisions for the amount of pulp tissue removal or retention depend on the diagnostic of pulp vitality,the overall treatment plan,the patient’s general health status,and pulp inflammation reassessment during operation.This statement represents the consensus of an expert committee convened by the Society of Cariology and Endodontics,Chinese Stomatological Association.It addresses the current evidence to support the application of pulpotomy as a potential alternative to root canal treatment(RCT)on mature permanent teeth with pulpitis from a biological basis,the development of capping biomaterial,and the diagnostic considerations to evidence-based medicine.This expert statement intends to provide a clinical protocol of pulpotomy,which facilitates practitioners in choosing the optimal procedure and increasing their confidence in this rapidly evolving field.
文摘Apical microsurgery is accurate and minimally invasive,produces few complications,and has a success rate of more than 90%.However,due to the lack of awareness and understanding of apical microsurgery by dental general practitioners and even endodontists,many clinical problems remain to be overcome.The consensus has gathered well-known domestic experts to hold a series of special discussions and reached the consensus.This document specifies the indications,contraindications,preoperative preparations,operational procedures,complication prevention measures,and efficacy evaluation of apical microsurgery and is applicable to dentists who perform apical microsurgery after systematic training.
文摘Intentional tooth replantation(ITR)is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions.ITR is defined as the deliberate extraction of a tooth;evaluation of the root surface,endodontic manipulation,and repair;and placement of the tooth back into its original socket.Case reports,case series,cohort studies,and randomized controlled trials have demonstrated the efficacy of ITR in the retention of natural teeth that are untreatable or difficult to manage with root canal treatment or endodontic microsurgery.However,variations in clinical protocols for ITR exist due to the empirical nature of the original protocols and rapid advancements in the field of oral biology and dental materials.This heterogeneity in protocols may cause confusion among dental practitioners;therefore,guidelines and considerations for ITR should be explicated.This expert consensus discusses the biological foundation of ITR,the available clinical protocols and current status of ITR in treating teeth with refractory apical periodontitis or anatomical aberration,and the main complications of this treatment,aiming to refine the clinical management of ITR in accordance with the progress of basic research and clinical studies;the findings suggest that ITR may become a more consistent evidence-based option in dental treatment.
基金Supported by Austrian Science Fund,No.Project 29440(to Andrukhov O)
文摘Mesenchymal stem cells(MSCs)are considered as an attractive tool for tissue regeneration and possess a strong immunomodulatory ability.Dental tissuederived MSCs can be isolated from different sources,such as the dental pulp,periodontal ligament,deciduous teeth,apical papilla,dental follicles and gingiva.According to numerous in vitro studies,the effect of dental MSCs on immune cells might depend on several factors,such as the experimental setting,MSC tissue source and type of immune cell preparation.Most studies have shown that the immunomodulatory activity of dental MSCs is strongly upregulated by activated immune cells.MSCs exert mostly immunosuppressive effects,leading to the dampening of immune cell activation.Thus,the reciprocal interaction between dental MSCs and immune cells represents an elegant mechanism that potentially contributes to tissue homeostasis and inflammatory disease progression.Although the immunomodulatory potential of dental MSCs has been extensively investigated in vitro,its role in vivo remains obscure.A few studies have reported that the MSCs isolated from inflamed dental tissues have a compromised immunomodulatory ability.Moreover,the expression of some immunomodulatory proteins is enhanced in periodontal disease and even shows some correlation with disease severity.MSC-based immunomodulation may play an essential role in the regeneration of different dental tissues.Therefore,immunomodulation-based strategies may be a very promising tool in regenerative dentistry.
文摘Revascularization of immature necrotic teeth is a reliable treatment alternative to conventional apexogenesis or apexification. In case 1, a 12-year-old boy had his necrotic, immature mandibular left second premolar treated with a revascularization technique. At a 24-month follow-up, periapical radiolucency had disappeared and thickening of the root wall was observed. In cases 2 and 3, a lO-year-old boy had his necrotic, immature, bilateral mandibular second premolars treated with the same modality. At 48-month （in case 2） and 42-month （in case 3） follow-ups, loss of periapical radiolucencies and increases in the root wall thickness were also observed.
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 grants (17-219 and 17-125) from the Osteology foundationSwitzerland. A.S. received grants from the Swiss Dental Association (288-15),the Swiss Society of Periodontology (SSP) and the Foundation for the Promotion of Oral Health and Research+1 种基金supported by a grant from the Osteology Foundation (14-126)supported by a grant from the Osteology Foundation and the Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), Chile
文摘Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester(CAPE), which is a potent inducer of heme oxygenase 1(HO1), is a central active component of propolis, and the application of propolis improves periodontal status in diabetic patients. Here, primary murine macrophages were exposed to CAPE. Target gene expression was assessed by whole-genome microarray, RT-PCR and Western blotting. The antioxidative and anti-inflammatory activities of CAPE were examined by exposure of the cells to hydrogen peroxide, saliva and periodontal pathogens. The involvement of HO1 was investigated with the HO1 inhibitor tin protoporphyrin(SnPP) and knockout mice for Nrf2, which is a transcription factor for detoxifying enzymes. CAPE increased HO1 and other heat shock proteins in murine macrophages. A p38 MAPK inhibitor and Nrf2 knockout attenuated CAPE-induced HO1 expression in macrophages. CAPE exerted strong antioxidative activity. Additionally, CAPE reduced the inflammatory response to saliva and periodontal pathogens. Blocking HO1 decreased the antioxidative activity and attenuated the anti-inflammatory activity of CAPE. In conclusion, CAPE exerted its antioxidative effects through the Nrf2-mediated HO1 pathway and its anti-inflammatory effects through NF-κB inhibition. However, preclinical models evaluating the use of CAPE in periodontal inflammation are necessary in future studies.
基金supported by the National Research Foundation(NRF) of Korea funded by the Ministry of Education,Science and Technology(MEST) (No.2009-0086835,2011-0014231,2012-0008693:Drs KY Kum,SH Han and SW Chang),South Korea
文摘A previous study demonstrated that alexidine has greater affinity for the major virulence factors of bacteria than chlorhexidine.The aim of this study was to compare the antimicrobial activity of 1%alexidine with that of 2%chlorhexidine using Enterococcus faecalis-infected dentin blocks.Sixty bovine dentin blocks were prepared and randomly divided into six groups of 10 each.E.faecalis was inoculated on 60 dentin blocks using the Luppens apparatus for 24 h and then the dentin blocks were soaked in 2%chlorhexidine or 1%alexidine solutions for 5 and 10 min,respectively.Sterile saline was used as a control.The antimicrobial efficacy was assessed by counting the number of bacteria adhering to the dentin surface and observing the degradation of bacterial shape or membrane rupture under a scanning electron microscope.Significantly fewer bacteria were observed in the 2%chlorhexidine-or 1%alexidine-soaked groups than in the control group(P<0.05).However,there was no significant difference in the number of bacteria adhering to the dentinal surface between the two experimental groups or between the two soaking time groups(P>0.05).Ruptured or antiseptic-attached bacteria were more frequently observed in the 10-min-soaked chlorhexidine and alexidine groups than in the 5-min-soaked chlorhexidine and alexidine groups.In conclusion,10-min soaking with 1%alexidine or 2%chlorhexidine can be effective against E.faecalis infection.
基金supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (No. 2012R1A1A1001473)
文摘All-trans retinoic acid（ATRA） inhibits matrix metalloproteinase（MMP）-2 and MMP-9 in synovial fibroblasts, skin fibroblasts,bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells（HDPCs）. The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA（mRNA） expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction（PCR）, respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol？L21ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs,which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.
基金supported by the National Natural Science Foundation of China(No.81200781)
文摘Calcium hydroxide（CH） is applied to improve disinfection of root canals in most root canal retreatment. This study aimed to analyze the CH removal efficacy using 7 different root preparing files（K file, pre-curved K file, EndoActivator, Ultrasonic file, pre-curved ultrasonic file, F file and needle irrigation alone） with apical transportation. Standardized models of curved canal with such apical transportation or not were set up before applying CH to root canal for 7 days. Seven techniques described above were used for its removal. Then the roots were disassembled and digital photos were taken. The ratio of residual CH in the overall canal surface was calculated using the image analyzer image pro plus 6.0. The data were analyzed using one-way ANOVA with post hoc Tukey test. Results revealed that CH was effectively removed（P〈0.05） by using all 6 mechanical methods except irrigation alone. In curved root canals with apical transportation, EndoActivator, pre-curved ultrasonic file and F file were found to be more effective in removing CH than the other four file（P〈0.001）, while there was no significant difference among EndoActivator, pre-curved ultrasonic file and F file groups（P〉0.05）. The percentage of residual CH in the canal with apical transportation was higher than that in the canal without apical transportation（P〈0.05）. In conclusion, CH can be hardly removed completely. Canal with apical transportation will result in insufficient CH removal. EndoActivator, pre-curved ultrasonic file and F file are more effective in the curved root canal with apical transportation.
