Objective To measure radiation filed distribution in the treatment room of the Varian Halcyon medical linear accelerator, and to provide a basis for shielding design and potential exposure analysis of treatment rooms for this type of accelerator. Methods Under the 6 MV X-ray (FFF) mode at a maximum dose rate of 800 MU/min and a maximum irradiation field of 28.00 cm × 28.00 cm, a total of 540 MU was delivered during gantry rotation. Radiation field distribution was measured using thermoluminescence dosimeters located at multiple points in the room. The measured data were then applied to shielding calculations, and the results were compared with those obtained using empirical formulas. Results The overall radiation levels in the treatment room were in the range of 12.2 µGy/540 MU to 5.520 Gy/540 MU, with the highest dose (5.520 Gy/540 MU) observed at the isocenter, and the lowest dose (12.2 µGy/540 MU) recorded at approximately 6.5 m from the gantry head. The radiation levels at most points were within the range of 100-1000 µGy/540 MU. At heights of 0.5, 1.1, and 1.7 m, the radiation field exhibited a rapid attenuation from the beam center outward, with a faster decay along the treatment couch direction (Y-axis) than along the perpendicular direction (X-axis). Shielding calculations based on the measured radiation field yielded required wall thicknesses of 1219 mm (east wall), 949 mm (south wall), 1235 mm (west wall), and 1252 mm (north wall), all of which were smaller than those calculated using empirical formulas. Conclusion Thermoluminescence dosimeter is suitable for multi-point in situ measurement of radiation field distribution in Halcyon accelerator treatment rooms. The measurement results can be used to optimize the shielding design of Halcyon accelerator treatment rooms.

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.
Microsurgery/standards* ; Humans ; Apicoectomy ; Contraindications, Procedure ; Tooth Apex/diagnostic imaging* ; Postoperative Complications/prevention & control* ; Consensus ; Treatment Outcome

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.
Humans ; Calcium Compounds/therapeutic use* ; Consensus ; Dental Pulp ; Dentition, Permanent ; Oxides/therapeutic use* ; Pulpitis/therapy* ; Pulpotomy/standards*

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.

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: Analyzing the characteristics of consonant errors in children with functional dysarthria in different age groups and the effect of speech training provides a reference for clinical treatment. Methods : This study followed medical ethics, and informed consent has been obtained from patients. Speech data from 388 patients with functional dysarthria were retrospectively studied. They were divided into two groups at the age of 6, namely, the preschool group (4-6 years old) of 226 patients and the school age group (6-13 years old, including 6 years old) of 162 patients. The characteristics of consonant pronunciation errors from four aspects were analyzed: average number of errors, pronunciation location, pronunciation method, and error type. One-on-one speech training was conducted, with a training frequency of once a week and once for 30 minutes. The training method was carried out in the order of phoneme training, syllable training, vocabulary training, sentence training, and short text and conversation training. The effects of speech training in the two groups were compared. Results: Analysis by pronunciation location: both age groups had the highest frequency of errors in tongue tip posterior sounds; the school age group had the lowest error frequency for labiodental consonants, and the preschool group had the lowest error frequency for bilabial consonants. According to the analysis of pronunciation mode, both age groups had the highest error frequency of aspirated affricate and the lowest error frequency of nasal sound. Analysis by error type: both age groups are mainly characterized by substitution and omission. Compared with the preschool group, most consonants of patients in the school group tend to improve in terms of pronunciation location, pronunciation mode, and error types. Compared with the preschool group, the two types of errors-palatalization and lateralization-increased in frequency in the school group, but the trend of increased lateralization was not statistically significant. After 6.7 and 5.5 sessions of speech training, the pronunciation of the preschool group and the school-age group significantly improved; the cure rate of the school-age group was 84.9% (118/139), and that of the preschool group was 77.1% (91/118). There was no statistically significant difference in the cure rate between the two groups. Conclusion Functional dysarthria may improve with age, but it may not completely self-heal. Children of different age groups can achieve good treatment results through scientific and reasonable speech training.

Objective:To evaluate the dosimetric effects of different aperture shape controller (ASC) parameters based on the Halcyon 3.0 accelerator in the hippocampal avoidance-whole brain radiotherapy (HA-WBRT) plans.Methods:This study enrolled 13 patients treated with WBRT using a Halcyon 3.0 accelerator at the Department of Radiotherapy of the Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine. According to different aperture shape controller (ASC) parameters, the HA-WBRT plans were divided into six groups, namely non, very low, low, moderate, high, and very high ASC settings, marked by AO, AVL, AL, AM, AH, and AVH, respectively. This study presented a statistical evaluation of the effects of different ASC parameters on conformity index (CI), homogeneity index (HI), radiation doses to the hippocampus and other organs at risk, and the plans’ execution efficiency. Furthermore, using two dose verification tools, namely ArcCHECK and Portal Dosimetry, this study delivered a comprehensive analysis of the differences in beam delivery precision of the plans with different ASC parameters.Results:The six groups all met the requirements for clinical treatment. They had similar CI and HI values, with no statistically significant differences ( P > 0.05). The AVH group showed better protection effects on organs at risk. Compared to the control group, the AVL group showed lower Dmax of brainstems but higher Dmax of chiasma opticum ( F = 6.26, 8.04, P < 0.05). Compared to the control group, the AH group showed lower Dmax of eyeballs but higher Dmax of optic nerves ( F = 2.04, 1.37, P < 0.05). In contrast, the AVH group exhibited lower Dmax of brainstems, eyeballs, and lens than the control group ( F = 6.26, 2.04, 2.02, P < 0.05). No statistically significant differences were observed in dosimetric indices of other organs at risk ( P > 0.05). As verified using ArcCHECK and Portal Dosimetry, the γ passing rates of the six groups were over 98% at 2%/2 mm and 100% at 3%/3 mm. The overall γ passing rates verified using ArcCHECK were lower than those verified using Portal Dosimetry. The maximum difference in the monitor unit among the six groups was less than 15, and these groups did not show significant differences in terms of execution efficiency. Conclusions:The HA-WBRT plans based on the Halcyon 3.0 accelerator can meet the requirements for clinical treatment. Different ASC parameters can significantly optimize the dosimetric parameters. Among them, the AVH parameters can highly reduce the radiation dose to organs at risk. Furthermore, different ASC parameters show insignificant effects on beam delivery precision and plan execution efficiency, meeting the verification standards for clinical therapeutic doses.

Objective:To study the effects of poly adenosine diphosphate ribose polymerase (PARP) inhibitors niraparib and pamiparib on the radiosensitivity of breast cancer cell lines MCF-7 and MDA-MB-436, and to explore its mechanism.Methods:MCF-7 and MDA-MB-436 cells were divided into control group, niraparib group, pamiparib group, radiation group, combination group treated with niraparib and radiation, and combination group treated with pamiparib and radiation, respectively. The effects of drugs on cell proliferation and radiosensitivity were measured by CCK-8 assay and colony formation assay, respectively. The effect of drugs combined with radiation on cell cycle and apoptosis were detected by flow cytometry. Immunofluorescence method was used to detect the changes of γ-H2AX focal number of cells. The expressions of FANCG, Bax and Bcl-2 mRNA and protein were detected by qPCR and Western blot, respectively.Results:Both niraparib and pamiparib inhibited the proliferation of breast cancer cells MCF-7 and MDA-MB-436 in a time-dose dependent manner. With the increase of irradiation dose, D0, Dq, SF2 value of MCF-7 and MDA-MB-436 cells decreased, and SER D0 and SER Dq value increased. Compared with control group, the percentages of cells in G 2/M phase were increased ( tMCF-7=41.66, 44.08, P<0.05; t436=24.69, 18.91, P<0.05), the percentage of cells in G 0/G 1 phase were decreased ( tMCF-7=8.67, 29.61, P<0.05; t436=26.39, 29.12, P<0.05), and the cell apoptosis rate was significantly increased ( tMCF-7=11.17, 11.71, P<0.05; t436=42.68, 15.89, P<0.05) in the combination group. Compared with control group, the number of γ-H2AX foci of MCF-7 cells in the radiation group and combination group treated with niraparib and radiation increased significantly at 2 h after irradiation ( t=8.89, 21.72, P<0.05). At 24 h after irradiation, the number of γ-H2AX foci basically returned to normal level in the radiation group but remained at a higher level in the combination group ( t=8.82, P<0.05). Compared with control group, the expressions of FANCG and Bcl-2 mRNA decreased ( tFANCG=14.07, P<0.05; tBcl-2=29.21, P<0.05), the expression of Bax mRNA increased ( t=8.90, P<0.05), and the expression of FANCG and Bcl-2 proteins decreased ( tFANCG=7.09, P<0.05; tBcl-2=10.24, P<0.05), while the expression of Bax protein increased ( t=2.90, P<0.05) in the combination group. Conclusions:PARP inhibitors niraparib and pamiparib can increase the radiosensitivity of breast cancer MCF-7 and MDA-MB-436 cells probably through down-regulating the expression of FANCG in FA-BRCA pathway, up-regulating apoptosis-related genes and inhibiting DNA damage repair.