Endodontic microsurgery is an important treatment for endodontic disease and maxillary sinusitis of endodontic origin of maxillary posterior teeth. However, endodontic microsurgery is challenging due to the close proximity between the maxillary posterior teeth and the maxillary sinus, which may lead to complications of mucosal perforation of the maxillary sinus floor. Endodontic microsurgery combined with maxillary sinus floor elevation is considered as a solution, namely natural tooth-related maxillary sinus floor elevation. The evaluation and design of natural tooth-related maxillary sinus floor elevation are closely related to local anatomic relationships. This article provides a systematic review of the anatomical considerations of endodontic microsurgery, namely natural tooth-related maxillary sinus floor elevation in the maxillary posterior region in terms of maxillary posterior teeth, alveolar ridge of the maxillary posterior region, and maxillary sinus. The literature review showed that a minimum of 3 mm of the root apex must be removed during endodontic microsurgery to eliminate the majority of apical ramification, lateral canals, and severe root curvatures. The height and thickness of alveolar ridge bone are important indicators for evaluating and designing endodontic microsurgery for maxillary posterior teeth. Maxillary sinus floor mucosa, maxillary sinus ostium, the proximity between maxillary posterior teeth and the maxillary sinus floor, maxillary sinus septa, posterior superior alveolar artery, and greater palatine artery, and possible maxillary sinus cysts are the main maxillary sinus-related considerations. When the maxillary sinus floor is below the line between the buccal and palatal roots, when the root apices contact or protrude into the maxillary sinus floor, or when the apical lesion is directly connected to the maxillary sinus mucosa, natural tooth-related maxillary sinus floor elevation is applicable. Anatomical considerations should be emphasized throughout endodontic microsurgery and natural tooth-related maxillary sinus floor elevation in the maxillary posterior region. Further studies are required to investigate the clinical design and difficulty assessment of natural tooth-related maxillary sinus floor elevation in different local anatomical relationships.

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.

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 evaluate the clinical efficacy of warm acupuncture combined with external application of Tibetan medicine Baimai Ointment in the treatment of low-back pain with cold-dampness type.Methods:Randomized controlled trial. Totally 60 outpatients in Tibetan Medicine Hospital of Cuona County from May to July of 2021 were selected as the observation objects, and they were divided into two groups by random number table method, with 30 cases in each group. The control group was treated with Baimai Ointment, and the treatment group was treated with warm acupuncture and Baimai Ointment. Both groups were treated for 2 weeks and followed up for 3 months. VAS scale and Oswestry disability index (ODI) were used to evaluate the low-back pain and dysfunction, and the clinical efficacy was evaluated.Results:The VAS scores of the treatment group were lower than those in the control group immediately after treatment and at the last follow-up ( t=-18.17, -6.05, P<0.01). The ODI score of the treatment group was lower than that of the control group at the last follow-up ( t=-15.86, P<0.01). The total effective rate was 96.7% (29/30) in the treatment group and 93.3% (28/30) in the control group, without statistical significance ( χ2=0.001, P=1.000). Conclusion:Warm acupuncture combined with Tibetan medicine Baimai Ointment can effectively improve the clinical symptoms of low-back pain with cold-dampness type, improve the quality of life of patients, and the clinical effect is satisfactory.

Background and Objectives: Regenerative endodontic procedures (REPs) are a research hotspot in the endodontic field. One of the biggest problems of REPs is that it is difficult to realize regeneration of pulp-dentin complex and functional reconstruction. The reason is still not clear. We hypothesize that the migration may be different in different dental stem cells. Periodontal ligament stem cells (PDLSCs) may migrate faster than stem cells of apical papilla (SCAPs), differentiating into cementum-like tissue, bone-like tissue and periodontal ligament-like tissue and, finally affecting the outcomes of REPs. Hence, this study aimed to explore the mechanism that regulates the migration of PDLSCs. Methods: and Results: After isolating and culturing PDLSCs and SCAPs from human third molars, we compared the migration of PDLSCs and SCAPs. Then we investigated the role of SDF-1α-CXCR4/CXCR7 axis in PDLSC migration. We further investigated the impact of Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) on PDLSC migration and the potential mechanism. PDLSCs showed better migration under both noninflammatory and inflammatory conditions than SCAPs. SDF-1α can promote the migration of PDLSCs by elevating the expression of CXCR4 and CXCR7, increasing the interaction between them, promoting expression of β-arrestin1 and activating the ERK signaling pathway. P. gingivalis LPS can promote the migration of PDLSCs toward SDF-1α through increasing the expression of CXCR4 via the NF-κB signaling pathway, promoting the expression of β-arrestin1, and activating the ERK signaling pathway. Conclusions This study helped elucidate the potential reason for the difficulty in forming pulp-dentin complex.

OBJECTIVES: This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps. METHODS: For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted. RESULTS: The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis. CONCLUSIONS Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.
Humans ; Tooth, Impacted/surgery* ; Molar ; Mandible ; Dental Pulp ; Root Canal Therapy ; Root Resorption/etiology* ; Tooth Extraction

Endodontic microsurgery is one effective method for preserving teeth affected by periapical disease, and is also an essential technique for treating difficult cases. However, due to the restricted operating space at the posterior site and the proximity of the root apex to the maxillary sinus, endodontic surgery in the posterior maxillary area represents great challenges. This article summarizes the anatomical relationship between the maxillary sinus and the maxillary posterior teeth, the influence on endodontic microsurgery, and the application of assistive techniques on maxillary posterior teeth, such as 3D-printed surgical guides and ultrasonic osteotomes. Literature review results show that the spatial relationship between the apex of maxillary posterior teeth and the maxillary sinus is usually divided into three categories: the apex enters the maxillary sinus; the apex contacts the bottom of the maxillary sinus; and there is a distance between the apex and the bottom of the maxillary sinus. CBCT should be performed before the operation, and the periapical state of the tooth and the maxillary sinus and the distance between the lesions and the sinus floor should be considered to evaluate the difficulty of the operation. Meanwhile, during surgery, equipment such as surgical guides, endoscopes and ultrasonic osteotomes should be used to ensure that the operation is safer, reliable, precise and less invasive, but the clinical popularity of ultrasonic osteotomes still needs further promotion. Moreover, high-quality clinical studies on the long-term effects of micro-apical surgery in the posterior maxillary area are still lacking.

Regenerative endodontic procedures (REPs) is a biologic-based treatment modality for immature permanent teeth diagnosed with pulp necrosis. The ultimate objective of REPs is to regenerate the pulp-dentin complex, extend the tooth longevity and restore the normal function. Scientific evidence has demonstrated the efficacy of REPs in promotion of root development through case reports, case series, cohort studies, and randomized controlled studies. However, variations in clinical protocols for REPs exist due to the empirical nature of the original protocols and rapid advancements in the research field of regenerative endodontics. The heterogeneity in protocols may cause confusion among dental practitioners, thus guidelines and considerations of REPs should be explicated. This expert consensus mainly discusses the biological foundation, the available clinical protocols and current status of REPs in treating immature teeth with pulp necrosis, as well as the main complications of this treatment, aiming at refining the clinical management of REPs in accordance with the progress of basic researches and clinical studies, suggesting REPs may become a more consistently evidence-based option in dental treatment.
Humans ; Consensus ; Regenerative Endodontics ; Dental Pulp Necrosis/therapy* ; Dentists ; Professional Role ; Dental Care

Objective: This study aims to compare the incidence of dentinal microcracks produced by ProTaper Universal (PTU) and ProTaper Gold (PTG) file systems during root canal procedures in different curved canals using a dyeing technique. Methods: Sixty extracted human molars were divided into 3 groups of 20 samples each in terms of root curvature (mild bending group, 10 °-19 °; moderate bending group, 20 °-29 °; severe bending group, 30 °-39 °). Ten samples of each group were then randomly allocated to the PTU and PTG file systems. After preparation, all roots were stained using a dyeing method and sectioned at the most curved plane and 2 mm below and above the most curved plane with a low-speed saw under cold water. A stereomicroscope was used to inspect dentinal microcracks at 60 × magnification, and differences between these three instrument groups were analyzed using the chi-square test. Results : The PTG file system induced significantly fewer dentinal microcracks for total, incomplete and complete cracks (P < 0.05), and the effect was more obvious with increasing canal curvature. Conclusion With the limitations of this in vitro study, it can be concluded that ProTaper Gold can result in fewer dentinal microcracks than ProTaper Universal.

Once pulp necrosis or apical periodontitis occurs on immature teeth, the weak root and open root apex are challenging to clinicians. Berberine (BBR) is a potential medicine for bone disorders, therefore, we proposed to apply BBR in root canals to enhance root repair in immature teeth. An in vivo model of immature teeth with apical periodontitis was established in rats, and root canals were filled with BBR, calcium hydroxide or sterilized saline for 3 weeks. The shape of the roots was analyzed by micro-computed tomography and histological staining. In vitro, BBR was introduced into stem cells from apical papilla (SCAPs). Osteogenic differentiation of stem cells from apical papilla was investigated by alkaline phosphatase activity, mineralization ability, and gene expression of osteogenic makers. The signaling pathway, which regulated the osteogenesis of SCAPs was evaluated by quantitative real time PCR, Western blot analysis, and immunofluorescence. In rats treated with BBR, more tissue was formed, with longer roots, thicker root walls, and smaller apex diameters. In addition, we found that BBR promoted SCAPs osteogenesis in a time-dependent and concentration-dependent manner. BBR induced the expression of β-catenin and enhanced β-catenin entering into the nucleus, to up-regulate more runt-related nuclear factor 2 downstream. BBR enhanced root repair in immature teeth with apical periodontitis by activating the canonical Wnt/β-catenin pathway in SCAPs.
Animals ; Berberine ; pharmacology ; Cell Differentiation ; drug effects ; Dental Papilla ; Male ; Osteogenesis ; drug effects ; Periapical Periodontitis ; therapy ; Rats ; Stem Cells ; cytology ; drug effects ; metabolism ; Wnt Signaling Pathway ; drug effects ; Wnt3A Protein ; genetics ; metabolism ; X-Ray Microtomography