The overall health condition of patients significantly affects the diagnosis,treatment,and prognosis of endodontic diseases.A systemic consideration of the patient's overall health along with oral conditions holds the utmost importance in determining the necessity and feasibility of endodontic therapy,as well as selecting appropriate therapeutic approaches.This expert consensus is a collaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence,aiming to provide general guidance on clinical procedures,improve patient safety and enhance clinical outcomes of endodontic therapy in patients with compromised overall health.

The bony window technique refers to cutting the intact bone plate to form a bone window and a free bone block to get access to lesions under the bone. At the end of the surgery, the dislocated bony lid needs to be repositioned to its original position. In endodontic microsurgery, compared with conventional osteotomy, the bony window technique has the advantages of improving the view of surgery and operability, reducing postoperative bone defects, promoting bone healing, and maintaining the integrity of the jaw outline. Accurate positioning and preparation of the bony window are important prerequisites for subsequent operations during the surgery, but it′s difficult in some situations, such as when the operative area is located posteriorly or the bone cortex on the lesion surface is thick and intact. What′s more, whether the free bone block can be stabilized in situ after repositioning is closely related to the prognosis of the surgery. The complementary application of digital navigation technology and bone cavity filling materials may help to improve the bony window technique and provide more possibilities for the retention of affected teeth in difficult cases.

Caries is an infectious disease in which the invasion of pathogens and their metabolites can activate the recognition and defense system of the pulpodentinal complex. In-depth understanding of the immune responses mediated by the pulpodentinal complex will help to estimate the real state of the dental pulp during the progression of caries and to take reasonable clinical treatment strategies, which can be more targeted and less invasive. Based on the physiology of the pulpodentinal complex, the present article introduce its immunocompetence and mechanism, reactive changes, clinical intervention and its significance during the caries progression, as to improve diagnostics as well as treatment strategies for caries.

Objective:To analyze the influence of operator′s experience on the quality and success rate of root canal treatment with new nickel-titanium instruments, providing support for improving the success rate of root canal treatment with new nickel-titanium instruments in clinic.Methods:Cases of root canal treatment and non-surgical root canal retreatment with 6-12 months recall performed by residents (resident group) with experience of 1-3 years and endodontic specialists (specialist group) with experience of 5-7 years were collected from the electronic medical system of the Department of Endodontics, School of Stomatology, Capital Medical University, from September 2020 to August 2021. All cases were prepared by engine-driven glide path files and controlled memory nickel-titanium finishing files. Chi-square test and logistic regression were used to analyze the differences and influencing factors of complications, filling quality and success rate of root canal treatment between the two groups.Results:A total of 277 cases performed by 24 residents and 3 specialists were included, 169 in the resident group and 108 in the specialist group. The clinical incidence of flare-ups was significantly higher in the resident group [3.6% (6/169)] than in the specialist group [0(0/108)] ( P=0.048). There were no significant differences in ledges, root canal transportations, perforations, or instrument separations between the two groups ( P>0.05). The prevalence of satisfactory fillings was 62.7% (106/169) in the resident group, which was significantly lower than that in the specialist group [86.1% (93/108)] ( P<0.05). The success rate of root canal treatment was 91.7% (155/169) and 94.4% (102/108) in the resident group and the specialist group, respectively, with no significant differences (χ 2=0.73, P=0.392). Multivariate analysis showed that the success rate of root canal treatment was related to complications and quality of root fillings ( P<0.05). Conclusions:Higher success rate of root canal treatment could be achieved by residents and endodontic specialists with engine-driven glide path files and controlled memory nickel-titanium files.

Endodontic diseases are a kind of chronic infectious oral disease.Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha.However,it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT).Recent research,encompassing bacterial etiology and advanced imaging techniques,contributes to our understanding of the root canal system's anatomy intricacies and the technique sensitivity of RCT.Success in RCT hinges on factors like patients,infection severity,root canal anatomy,and treatment techniques.Therefore,improving disease management is a key issue to combat endodontic diseases and cure periapical lesions.The clinical difficulty assessment system of RCT is established based on patient conditions,tooth conditions,root canal configuration,and root canal needing retreatment,and emphasizes pre-treatment risk assessment for optimal outcomes.The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT.These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics.

Chemical cleaning and disinfection are crucial steps for eliminating infection in root canal treatment.However,irrigant selection or irrigation procedures are far from clear.The vapor lock effect in the apical region has yet to be solved,impeding irrigation efficacy and resulting in residual infections and compromised treatment outcomes.Additionally,ambiguous clinical indications for root canal medication and non-standardized dressing protocols must be clarified.Inappropriate intracanal medication may present side effects and jeopardize the therapeutic outcomes.Indeed,clinicians have been aware of these concerns for years.Based on the current evidence of studies,this article reviews the properties of various irrigants and intracanal medicaments and elucidates their effectiveness and interactions.The evolution of different kinetic irrigation methods,their effects,limitations,the paradigm shift,current indications,and effective operational procedures regarding intracanal medication are also discussed.This expert consensus aims to establish the clinical operation guidelines for root canal irrigation and a position statement on intracanal medication,thus facilitating a better understanding of infection control,standardizing clinical practice,and ultimately improving the success of endodontic therapy.

Objective:To study the effects of the apical dentin surface morphology resected with Er∶YAG laser on the proliferation of human periodontal ligament cells(hPDLCs).Methods:66 single premolars were randomly divided into 3 groups(n=22),and the api-cal root slices were made by resection perpendicular to the root long axis 3 mm from the apex using high-speed handpiece(group A),piezosurgery(group B)and Er∶YAG laser(group C),respectively.SEM was used to observe the apical dentin surface in the aspects of debris,smear layer,dentinal tubules,cracks,ablation characteristics and the dentin surface roughness was measured.hPDLCs were clutured on the surface of the slices of the groups,CCK-8 method was used to detect cell proliferation on the samples at 24,48 and 72 h of culture,respectively.Results:The surface preparition time of group A was shorter than that of group B and C(P＜0.001).SEM observation showed that in group C,there was no residual debris or stained layer,and dentin tubule was visible on the dention sur-faces.Detritus and stained layers were observed in group A and B,and dentin tubule was not observed in group A.Cracks were observed in all the groups,but less in group C.Roughness(nm)of group C(1 487.13±295.90)was higher than that of group A and B(P＜0.001).CCK-8 assay showed that the cell proliferation(A value)of all groups increased gradually with the culture time after 24,48 and 72 h of hPDLCs seeded on the root surface.And the cell proliferation in group C was the most significant than that in group A and B(P＜0.05)at 48 and 72 h.Conclusion:The morphological performance of the apical dentin surface resected with Er∶YAG laser is more conducive to hPDLCs growth than that with the ultrasound and burs.

The dental operative microscope has been widely employed in the field of dentistry, particularly in endodontics and operative dentistry, resulting in significant advancements in the effectiveness of root canal therapy, endodontic surgery, and dental restoration. However, the improper use of this microscope continues to be common in clinical settings, primarily due to operators' insufficient understanding and proficiency in both the features and established operating procedures of this equipment. In October 2019, Professor Jingping Liang, Vice Chairman of the Society of Cariology and Endodontology, Chinese Stomatological Association, organized a consensus meeting with Chinese experts in endodontics and operative dentistry. The objective of this meeting was to establish a standard operation procedure for the dental operative microscope. Subsequently, a consensus was reached and officially issued. Over the span of about four years, the content of this consensus has been further developed and improved through practical experience.
Humans ; Dentistry, Operative ; Consensus ; Endodontics ; Root Canal Therapy ; Dental Care

Digital guided therapy (DGT) has been advocated as a contemporary computer-aided technique for treating endodontic diseases in recent decades. The concept of DGT for endodontic diseases is categorized into static guided endodontics (SGE), necessitating a meticulously designed template, and dynamic guided endodontics (DGE), which utilizes an optical triangulation tracking system. Based on cone-beam computed tomography (CBCT) images superimposed with or without oral scan (OS) data, a virtual template is crafted through software and subsequently translated into a 3-dimensional (3D) printing for SGE, while the system guides the drilling path with a real-time navigation in DGE. DGT was reported to resolve a series of challenging endodontic cases, including teeth with pulp obliteration, teeth with anatomical abnormalities, teeth requiring retreatment, posterior teeth needing endodontic microsurgery, and tooth autotransplantation. Case reports and basic researches all demonstrate that DGT stand as a precise, time-saving, and minimally invasive approach in contrast to conventional freehand method. This expert consensus mainly introduces the case selection, general workflow, evaluation, and impact factor of DGT, which could provide an alternative working strategy in endodontic treatment.
Humans ; Consensus ; Endodontics/methods* ; Tooth ; Printing, Three-Dimensional ; Dental Care ; Cone-Beam Computed Tomography ; Root Canal Therapy

Objective:To study the cross-sectional morphology of root canal system of Tibetan mandibular incisors by micro-CT.Methods:From October 2019 to October 2020, one hundred and thirty-six mandibular incisors were collected from Tibetan patients [(51.9±16.4) years old, range from 25 to 80 years] who underwent teeth extraction due to severe periodontitis at the Department of Stomatology, Tibetan Hospital of Traditional Tibetan Medicine, including 84 mandibular central incisors and 52 mandibular lateral incisors. These teeth were scanned at 23 μm voxel size resolution. Root lengths from cemento-enamel junction (CEJ) to apex of mandibular incisors were measured. According to the length, the root was divided as cervical 1/3, middle 1/3 and apical 1/3, and the numbers of root canals were recorded simultaneously. The major diameter, minor diameter, and dimension were measured per millimeter in cross section for mandibular incisor with single root canal, and the ratio of major diameter to minor diameter (D max/D min) as well as roundness were calculated for morphological analysis. The diversions and conversions from CEJ to apex in cross section were recorded for mandibular incisor with multiple root canals. Results:For mandibular central incisors with single root canal, the D max/D min was highest in middle 1/3 of the root [1.99 (1.31, 2.79)], which was significantly higher than cervical 1/3 and apical 1/3 ( P=0.010, P=0.003). The roundness was least in middle 1/3 [0.47 (0.31, 0.66)], which was significantly lower than cervical 1/3 and apical 1/3 ( P=0.010, P=0.001). For mandibular central incisor with multiple root canals, the highest incidence of multiple root canals was 40.5% (34/84), and mainly detected in middle 1/3 of the root [32.1% (27/84)]. For mandibular lateral incisor with single root canal, the roundness was greatest in apical 1/3 of the root [0.61 (0.49, 0.71)], which was significantly higher than cervical 1/3 ( P=0.001) and middle 1/3 ( P=0.001). The highest incidence of multiple root canals was 34.6% (18/52), all of which were detected in apical 1/3. Conclusions:In Tibetan mandibular central incisors, the cross-sectional morphology of root canals was long and narrow in middle 1/3, and multiple root canals were more likely to be found here. In Tibetan mandibular lateral incisors, the cross-sectional anatomy of root canal was relatively close to circle in apical 1/3, but the shape was still so irregular that one root canal may divide into two here.