Primary tooth root canal therapy is a treatment performed on primary teeth diagnosed with pulpitis or periapical periodontitis. This procedure requires perfect instrumentation, disinfection, and filling of root canals to eliminate infection, control inflammation, relieve pain, prevent pathological effects on inherited permanent tooth, and prolong primary tooth preservation. This paper reviews the research history on primary tooth root canal treatment and summarizes the progress on primary tooth root canal treatment, including anatomical morphology, root canal preparation, root canal disinfection, root canal filling, and application of antibiotics.

Occlusal reconstruction aims to restore the compromised dentition and rehabilitate its function; which is demanding and challenging, even to the well experienced prosthodontists. Analyzing the sophisticate clinical information gives fundamental validity to the subsequent treatment planning. In the whole process, the applied workflow should ensure the transmission of diagnostic information without compromise or error. Certain procedures predetermine the clinical outcome, and they should be given due attention. In this review, the key considerations, including analyzing the pathogenesis for the worn dentition, were briefly addressed to better understand the occlusal reconstruction.

Ankyloglossia is a congenital condition characterized by a short lingual frenulum, which may result in the restriction of tongue movement and function. Considerable controversy regarding the diagnosis, clinical significance, and management of the condition remains, and great variations in practice have been recorded. Indeed, attitudes toward ankyloglossia differ among professional groups, and opinions may vary remarkably even among those within the same specialty. This article reviews the embryology, genetics, diagnosis, clinical presentation, and treatment of ankyloglossia to help physicians better understand and treat the condition.

Dentofacial deformities secondary to condylar hyperplasiais a kind of disease presenting facial asymmetry, malocclusion, temporomandibular joint dysfunction, and other symptoms caused by non-neoplastic hyperplasia of the condyle. The etiology is still unknown, and currently, pre- and post-operative orthodontics accompanied by orthognathic surgery, temporomandibular joint surgery and jawbone contouring surgery are the main treatment methods. A personalized treatment plan was developed, considering the active degree of condyle hyperplasia, the severity of the jaw deformity, and the patient’s will, to correct deformity, obtain ideal occlusal relationship, and regain good temporomandibular joint function. Combined with the author’s clinical experience, the etiology, clinical and imageological features, treatment aims, and surgical methods of condylar hyperplasia and secondary dentofacial deformities were discussed in this paper.

A clear shoulder platform that can be easily identified by doctors and technicians or machines (mouth scan and warehouse scan) is important to obtaining a good long-term and stable fixed prosthesis treatment effect. At present, the preparation of the shoulder platform is usually based on free hands, and the practical operation is mainly guided by experience. Moreover, no comprehensive and objective preoperative design, intraoperative verification, and final test are available. Thus, the accuracy of shoulder platform preparation needs to be improved. In this study, the clinical pathway of “three determination, three selection, and three steps” with high accuracy of preparation and the precise shoulder preparation method of “bur-tip guidance” are proposed in detail.

Malocclusion is one of the three most common oral diseases reported by World Health Organization(WHO). In China, its incidence rate is rising. Malocclusion seriously affects the dental and maxillofacial function, facial appearance and growth development of nearly 260 million children in China, and what is more, it affects their physical and mental health development. Malocclusion occurrence is related to genetic and environmental factors. Early treatment of malocclusion can create a good dental and maxillofacial development environment, correct abnormal growth and control the adverse effects of abnormal genetic factors. It can effectively reduce the prevalence of children's malocclusion and enhance their physical and mental health. This is an urgent need from the economic perspective of our society, so it has great practical and social significance. Experts from the project group “standard diagnose and treatment protocols for early orthodontic intervention of malocclusions of children” which initiated by China National Health Institute of Hospital Administration wrote the “China Experts' Consensus on Preventive and Interceptive Orthodontic Treatments of Malocclusions of Children”, which aims to guide and popularize the clinical practice, improve the clinical theory and practice level, and accelerate the disciplinary development of early treatment of children's malocclusion in China. The consensus elaborates the harmfulness of malocclusion and the necessity of early treatment, and brings up the principles and fundamental contents. Based on the law of dental and maxillofacial development, this paper puts forward the guiding suggestions of preventive and interceptive treatments in different stages of dental development ranging from fetus to early permanent dentition. It is a systematic project to promote and standardize the early treatment of malocclusion. Through scientific and comprehensive stratified clinical practice and professional training, the clinical system of early treatment of malocclusion in China will eventually be perfected, so as to comprehensively care for children's dental and maxillofacial health, and improve their oral and physical health in China.

Osteonecrosis of the jaw could occur after intake of bisphosphonate drugs, which are widely used to treat osteoporosis and bone metastasis of malignant tumors. This effect has aroused concern among dentists. In this paper, a case of bisphosphonate-related osteonecrosis caused by implant is reported, and the pathogenesis, diagnosis, prevention, and treatment of bisphosphonate drug-induced osteonecrosis are described through a literature review. The effects of bisphosphonate drug treatment on dental implants are also discussed.

Thromboembolic diseases, which comprise venous thromboembolic diseases and arterial thromboembolic diseases, have become the number one cause of death worldwide. To prevent or treat thrombosis, patients with thromboembolic diseases need to take antithrombotic drugs, which would increase the risk of bleeding during and after surgery. Tooth extraction is the most common operation in oral and maxillofacial surgery clinics. Although patients given oral antithrombotic drugs do not need to undergo drug withdrawal, the perioperative management of such patients remains confusing to most clinicians. Moreover, the potential risk factors for bleeding warrant further study. To improve the clinicians’ knowledge of perioperative management for patients subjected to tooth extractions with oral antithrombotic drugs, experts have drafted this consensus focusing on preoperative bleeding risk assessment, intraoperative operating norms, and postoperative care to summarize the points needing attention.

In esthetic rehabilitation, methods used to enhance the margin quality have always been the focus and difficulty of improving the level of diagnosis and treatment, prevention and treatment of complications, and collaboration between clinicians and technicians. However, it is impeded by the ambiguous definition and classification of margin, unstandardized tooth preparation, manufacturing process of restoration, and lack of reliable means of checking the quantitative requirements of preparation or restoration. The digital technologies that are increasingly applied, such as intra-oral scanner, impression scanner, and computerized numerical control cutting machine, have strict requirements about margin quality. Failure of recognizing margins by these scanners will hinder the digital process of diagnosis and treatment. Even if these sharp and narrow margins are successfully scanned, they cannot be milled accurately. To overcome these problems, this article demonstrated the clear and complete definition of preparation margin and restoration margin, as well as their subclassifications, by analyzing the target restoration space from a geometric perspective. Practical approaches to measuring the margin width and inspecting the margin quality were proposed. The new and full understanding and proposal about preparation margin and restoration margin characterized by measurements will effectively support the thoroughly digitalized process of esthetic rehabilitation using porcelain in fixed prosthodontics, which is based on the guidance of values.

Pregnancy epulis is a tumor-like lesion with high prevalence in China. The local lesion, the general condition of the pregnant patient, and the complications during treatment should be taken into consideration when making a treatment plan for pregnancy epulis. In this study, three representative pregnancy epulis cases were presented, and related studies at home and aboard were reviewed to summarize the etiology, differential diagnosis, treatment, and prevention of pregnancy epulis and share the clinical experience in the treatment of pregnancy epulis.

Bulk-fill composite resin are simple to operate, and they reduce polymerization shrinkage and microleakage compare to traditional resin-based composites. However, their clinical application could be affected by numerous factors, such as the material itself, light curing, placement techniques, storage condition, and preheating. This review aimed to summarize the definitions, classifications, indications, clinical properties, and influencing factors of the clinical application of bulk-fill resin-based composites and discuss the ways to improve their clinical effectiveness.

Peri-implantitis is one of the most common complications in dental implant treatment. Peri-implantitis is a crucial implication of implant failure, which is characterized by high morbidity and intractability. Thus, how to understand peri-implantitis correctly and deeply, and how to prevent its occurrence, are important problems that every dental implant surgeon has to face.

The development of clinical implant dentistry was intensively affected by dental implant design improvement and innovation, which brought about new concept, even milestone-like changes of clinical protocol. The current improve-ments of dental implant design and their clinical importance could be highlighted as followings: 1) The implant apical design influences the implant preliminary stability in immediate implant. The apical 3-5 mm design of implant makes implant stable in immediate implant, because this part would be screwed into alveolar bone through fresh socket, the other part of implant could not be tightly screwed in the socket because of smaller implant diameter. Implant apical form, screw design, self-taping of apical part would be essential for immediate implant. 2) The enough preliminary stability of implant makes immediate prosthesis possible. When osseointegration does not occur, the implant stability comes from a mechanical anchorage, which depends on implant form, screw thread and self-taping design. 3) Implant neck design may have influence for soft tissue recession in esthetic zone. The implant with large shoulder would not be selected for the esthetic area. The platform design may be more favorable in the area. 4) The connection design between implant and abutment is thought a very impor-tant structure in implant long-term stability. Moose taper and “tube in tube” were well documented structure design in 20-year clinical practice in Peking University. 5) In last 15 years, the plenty studies showed the platform design of implant had positive influence in implant marginal bone level. Whatever in single implant restoration or multi-implant prosthesis. 6) The digital technology makes clinical work more precise and high-tech. This would be a trend in implant dentistry. New generation of chair-side digital computer-aided design/computer-aided manufacturing makes immediate prosthesis without conventional impression possible. 7) New abutment design have changed clinical protocol greatly. The All-on-four concept and Weldone concept benefit both from the abutment innovation, which were large angulated abutment and special welding abutment materials.

Objective This study aimed to investigate the feasibility of gelatin methacryloyl (GelMA) hydrogel loa-ded with minocycline-chitosan-nanoparticles (MCN) for the treatment of periodontitis in vitro and vivo. Methods MCN were synthesized by ionic gel method. GelMA/MCN composite hydrogels were prepared by compounding MCN with GelMA hydrogel. The materials were characterized by transmission electron microscope, scanning electron microscopy, and Fourier transform infrared spectroscopy. The degradation behavior and drug release rates of hydrogels were evaluated. The antibacterial activity of GelMA/MCN hydrogel against Porphyromonas gingivalis was detected, and the minimum antibacterial concentration was determined. Biocompatibility and osteogenic experiments were conducted under a simulated periodontitis environment. A rat model of periodontitis was constructed to observe the therapeutic effects of GelMA/MCN hydrogel. Results MCN was successfully synthesized with a particle size of about 80 nm, while the structures of GelMA/MCN had no significant differences from GelMA. MCN and GelMA/MCN released minocycline slowly and steadily. Bacterial growth was completely inhibited when the MCN concentration was higher than or equal to 0.2 mg·mL^-1. GelMA/MCN hydrogels exhibited good biocompatibility at effective antimicrobial concentrations under the simulated periodontitis environment with the enzyme. The in vivo results showed that GelMA/MCN prevented the progression of periodontitis and promoted the repair of bone defects. Conclusion GelMA/MCN composite hydrogel can release minocycline slowly and steadily and has good antibacterial activity and biocompatibility to promote the repair of periodontitis bone defects.

The morbidity rate of medication-related osteonecrosis of the jaws (MRONJ) increased rapidly in recent years. Thusfar, the mechanism of MRONJ has no consensus. The possible mechanisms may include bone remodeling inhibition theory, angiogenesis inhibition theory, oral microorganism infection theory, immunosuppression theory, cytotoxicity-targeted oral epithelial cells, microcrack formation of maxillary or mandibular bone, and single nucleotide polymorphism. However, the efficacy of prevention and treatment based on a single mechanism is not ideal. Routine oral examination before MRONJ-related drug treatment, treatment of related dental diseases, and regular oral follow-up during drug treatment are of great significance for the prevention of MRONJ. During the treatment of MRONJ, the stage of MRONJ must be determined accurately, treatment must be standardized in accordance with the guidelines, and personalized adjustments must be made considering the specific conditions of patients. This review aimed to combine the latest research and guidelines for MRONJ and the experiences on the treatment of MRONJ in the Maxillofacial Surgery Department of West China Hospital of Stomatology, Sichuan University, and discuss the strategies to improve the clinical process.

Decompression and curettage can result are effective as treatments for large jaw cysts, which are common diseases in the clinic. Based on a treatment used in a previous study, this paper proposes a “three-step method” to treat large jaw cyst and repair the bone defect by decompression, curettage, and autologous dental bone powder implantation. This paper introduces the processes and key points of the operation involved in the abovementioned method.

The mixed dentition stage is the period between primary and permanent dentition. The following biological processes are complicated and variable: jaw growth, development of inherited permanent teeth embryo, physiological absorption of primary teeth, restoration of surrounding alveolar bones, and growth and function establishment of soft tissues. For the normal development of the jaw, the establishment of the good occlusion relationship, development, and function of soft tissue is very important, whether or not the primary teeth are normally replaced by the permanent teeth in the mixed dentition stage. The eruption space is linked to the normal replacement of primary and permanent teeth. The presence of a mixed dentition space results in the incidence and progression of malocclusion and impacts the normal growth and development of the occlusion, jaw, and face. Space management in the mixed dentition stage is a crucial means to prevent and reduce malocclusion. The following were discussed and analyzed: the possible space problems, why the size of the space was affected, the content that needs to be assessed, and the methods of space management in the mixed dentition that can be used to unify and standardize the management of mixed dentition. This paper was developed to serve as a guide for regulated space management during the mixed dentition period.

An increasing number of implant restoration abutment types are produced with the rapid development of dental implantology. Although various abutments can meet different clinical demands, the selection of the appropriate abutment is both difficult and confusing. This article aims to help clinicians select the appropriate abutment by describing abutment design, types, and selection criteria.

Perforations are common complications of root canal therapy. In clinic, perforations that were improperly and untimely repaired can seriously affect the prognosis of teeth after root canal treatment. At present, the status of perforation repair in our country is worrisome. This paper focused on the progress of perforation repair in the country by discussing the current situation of repair methods and materials. This review aims to improve knowledge and aid clinical doctors in the sophistication of perforation repair in order to improve the retention rate of root-canal-treated teeth.

Objective To evaluate the clinical effect of semi-attached quad-helix appliance in expanding the narrow maxillary arches in patients with cleft lip and palate. Methods 15 cases with cleft lip and palate were selected and treated by semi-attached quad-helix appliance. Before, during, and after treatment, the dental arch width between cuspid, the first premolar and first molar were measured. Results The upper dental arches of all patients were expanded effectively in about five months. After orthodontic treatment, the upper dental arches were expanded, and the teeth were alined regularly, which provided good conditions for alveolar bone grafting. Conclusion The semi-attached quad-helix appliance with the fixed orthodontic treatment can expand the narrow maxillary arches in patients with cleft lip and palate effectively and conveniently.

Pediatric dentistry should focus not only on the treatment of various oral diseases during the entire growth and development of children but also on the early prevention, diagnosis, and intervention of various oral diseases in this process. Early identification and removal of risk factors or early intervention for common oral diseases is necessary to the implemen-tation of oral health management for pregnant women, infants, preschool and school-age children, and adolescents with diffe-rent general and oral physiological characteristics and common oral diseases. The treatment enables the growth and develop-ment of the teeth, as well as occlusion and facials along the normal trajectory, ultimately achieving the functional perfection and aesthetic coordination of the cranio-maxillary and occlusion.

Cheilitis is a general term for various types of inflammatory diseases that occur on the lips. The etiology differs and the clinical manifestations and pathological features overlap, leading to difficulties in clinical diagnosis. Reasonable classification is conducive to the diagnosis of cheilitis. However, its classification is difficult because of its cha-racteristics. At present, scholars have proposed two different classification schemes, but a unified classification standard has not yet been established. We classified cheilitis based on its etiology, clinical manifestations, pathological characteristics, and relationship with systemic and special diseases on the basis of special medical reports and by combining clinical practice experience and summarizing previous cheilitis diagnosis and treatment literature. In accordance with this classification method, we proposed suggestions for the clinical diagnosis of cheilitis to provide a reference for the clinical diagnosis and treatment of complex cheilitis.

With a case of mesial impaction of maxillary first and second molar, the mechanical analysis and clinical applications of a self-made helical spring for the uprighting treatment of mesial impacted molars was introduced.

External apical root resorption is among the most common risks of orthodontic treatment, and it cannot be completely avoided and predicted. Risk factors causing orthodontic root resorption can generally be divided into patient- and treatment-related factors. Root resorption that occurs during orthodontic treatment is usually detected by radiographical examination. Mild or moderate root absorption usually does no obvious harm, but close attention is required. When severe root resorption occurs, it is generally recommended to suspend the treatment for 3 months for the cementum to be restored. To unify the risk factors of orthodontic root resorption and its clinical suggestions, we summarized the theoretical knowledge and clinical experience of more than 20 authoritative experts in orthodontics and related fields in China. After discussion and summarization, this consensus was made to provide reference for orthodontic clinical practice.