Instrument separation is one of the most common complications of root canal treatment, and it is also a clinical problem that plagues many dentists. This article summarized the causes of root canal instrument separation, handling decisions, clinical disposal process, the removal techniques commonly used in clinics, and the post-treatment problems that may arise following root canal treatment. It aimed to investigate the rational disposal options for endodontic instruments that have been separated. In addition, this article also explored the specifications for removing separated instruments, so as to improve the success rate of treatment and increase tooth survival.

Root canal therapy is a conventional treatment for pulpal and periapical diseases. Intracanal interappointment medicaments are important in treatment of pulpal necrosis and apical periodontitis. In addition to killing microorganisms, intracanal medicaments may promote tissue healing and prevent reinfection. The most commonly used intracanal medicaments are calcium hydroxide, chlorhexidine digluconate, and triple antibiotic paste, which can not offer excellent efficacy and safety. The progress of molecular biology and nanotechnology has promoted the development of new antibacterial drugs represented by antimicrobial peptides and nanoparticles. The present article introduces the common used intracanal medicaments in endodontics, and the progress of developing novel medicaments. The development trend of intracanal medicaments in endodontics is also discussed.

Technically speaking, with advances in alveolar surgical techniques, almost all impacted teeth can be extracted. However, there is a trend in recent years that many practitioners of alveolar surgery are aggressive and fanatical about the extraction of impacted teeth. It seems that all impacted teeth should be extracted, and that the competence of the alveolar surgeon can only be reflected in the difficulty of the impacted tooth removal. Indications for the extraction of an impacted tooth, especially for the prophylactic extraction, are often overlooked. In this article, we reviewed the evidence on the indications for the extraction of impacted teeth in recent years, and discussed the "do′s and don′ts" in impacted tooth removal, from the perspectives of the health of both the adjacent teeth, and the maxillomandibular system, the value of retaining impacted teeth, and the shift in the demand for dental implant. Together with the clinical experience of the authors, it is expected to provide some reference for the alveolar surgeons.

In recent years, the alveolar surgery has made significant progress in clinical technology. The concept of minimally invasive surgery has been widely recognized and promoted. Minimally invasive technology is also becoming increasingly mature. However, some physicians focus on minimally invasive surgery while neglecting functional surgery in clinical practice. As to alveolar surgery, the author asserts that ″minimally invasive surgery″ is only the jumping-off point, while ″functional surgery″ is the imperative and ultimate goal. This article explored the connotation and clinical significance of functional alveolar surgery to attract the attention, communication and resonance of the majority of physicians in four aspects, including the preservation and restoration of alveolar bone function, the preservation and restoration of tooth function, the rational management of wisdom tooth function, and the preservation or restoration of neural function.

Based on the reports of the previous Workshops in 2017 and 2019, the third joint Workshop by the European Federation of Periodontology (EFP) and the European arm of the World Organization of Family Doctors (WONCA) (2022) discussed and summarized the associations between periodontitis and cardiovascular diseases, diabetes and respiratory diseases, and the implications for dentists and family doctors. The role of dentists and family doctors in managing non-communicable diseases and promoting healthy lifestyles was discussed as well. This article briefly introduced the main content of this Workshop and explored the enlightenments about multiple disciplinary team treatment combining with the national conditions of China.

Cleft palate is one of the most common congenital maxillofacial deformities, often affecting the physical and psychosocial function of patients. The goal of cleft palate repair is to reconstruct the palatal structure and restore speech function. This review aimed to demonstrate the historical development of cleft palate repair and discuss the following aspects: two major goals of cleft palate repair, the goals of modern cleft palate repair, the strategy to achieve new goals of cleft palate repair, and the future development of cleft palate repair.

Traumatic dislocation of young permanent teeth is common in children and adolescents. It may be caused by many factors and divided into several types. Total dislocation injury has a high incidence, and affects the dental and maxillofacial development and mental health of children and adolescents. Timely and correct diagnosis, treatment plan, follow-up and record are very important for the recovery of dislocated traumatic teeth. In this article, the diagnostic key points, treatment principles and prognosis of dislocation injury of young permanent teeth were elaborated by mainly referring to the latest criteria formulated by the International Association of Dental Trauma in 2020 (IADT guidelines), in order to provide references for the clinical diagnosis and treatment.

Due to the development of novel dental materials and digital techniques, the basic and clinical researches focusing on dental caries have been accumulated recently, which also promotes the clinical validation for the early diagnosis, comprehensive prevention, and functional-aesthetic treatment with minimal invasive intervention. By searching the literature, this article reviewed the current novel techniques that can be used to detect and diagnose caries, along with their clinical application, advantages and disadvantages, so as to provide references for the clinical application.

Tertiary lymphoid structures (TLSs) are organized aggregates of immune cells that form postnatally in nonlymphoid tissues. TLSs are not found under physiological conditions but arise in the context of chronic inflammation, such as autoimmune diseases, chronic infection, and cancer. In the setting of cancer development, TLSs facilitate the influx of immune cells into the cancer site and have therefore attracted interest as a means of improving anticancer immunity and favorable treatment response in patients. In spite of their presumed importance, the drivers of TLSs formation in cancer and the contribution of these structures to intratumoral immune response remain incompletely understood. In this article, the biology of TLSs and their recent advances in oral cancer research were reviewed.

Biodegradable bone adhesives attract increasing attention in biomaterial research. These adhesives have exhibited great potential in fracture fixation and bone defect treatment, but they are not commonly used in Dentistry. Recently, researchers have developed a degradable super bone adhesive with excellent adhesion, biocompatibility and performance in promoting bone regeneration. Their findings made new breakthroughs in bone adhesion, tooth bonding and bone regeneration. This article aimed to review their findings and discuss the related research prospects.

Inferior alveolar nerve (IAN) injury was mainly caused by the extraction of the mandibular third molar, and it is regarded as a difficult clinical problem since its symptoms including numbness, hypersensitivity, and pain influence the patients′ quality of life. This article reviewed the clinical signs, pathological changes, functional assessment, risk factors, and prevention progress of IAN injury in order to provide references for understanding its causes and pathological mechanisms, and developing its evaluation and clinical prevention strategies.

In recent years, a new type of resin matrix ceramic composite material has already been applied to restore tooth defection as well as to manufacture crowns on implants. It mainly includes two categories: Resin-based ceramic (RBC) and polymer-infiltrated ceramic network (PICN) . This paper provided a review of the mechanical properties, aesthetic characteristics, and clinical applications of resin matrix ceramic composite materials. The results indicated that the mechanical properties of resin matrix ceramic composite materials were between resin composite and ceramics, which were slightly higher than that of resin but significantly lower than that of reinforced glass-ceramics and zirconia. The advantages of such materials included their elastic modulus being close to that of enamel, and better fatigue resistance compared to ceramics. However, further optimization is needed in terms of mechanical strength and fracture toughness. The transparency of resin matrix ceramic composite materials was not as good as that of reinforced glass-ceramics, and their color stability was between resin composite and ceramics. In terms of clinical performance, resin matrix ceramic composite materials have been mainly used for inlays, onlays, and partial crowns currently, exhibiting similar survival rates to ceramics in the short-term clinical follow-ups. PICN may be more suitable for implant-supported full crowns. More evidence is needed to support the long-term clinical performance of these materials.

With the development of modern medical model and the progression of patients′ needs, dentoalveolar surgery, as the most classic speciality of stomatology, has been involved in the development of comfortable therapy in China from the very beginning with inhalation and intravenous sedation as the entry point. As a diagnosis and treatment concept, comfortable therapy is to make patients feel relaxed, comfortable and pleasant in the whole process of diagnosis, treatment and rehabilitation thgrough combining technology with humanistic care and psychological relief based on the core model of modern medicine. It consists of clinical techniques that mainly include but not limited to: behavioral management, painless injection, local anesthesia, analgesic techniques, sedation, general anesthesia, and minimally invasive treatment techniques. Dentoalveolar surgery should introduce the concept of comfortable treatment in the whole process in the future. Preoperatively, a variety of painless, local anesthesia and sedation techniques should be used. Intraoperatively, minimally invasive surgery should be performed. Postoperatively, pain management strategies should be taken and attention shoud be paid to the postoperative rehabilitation to achieve a soothing and relaxing experience for patients. Also, attention should be paid to the occupational risks of medical staff, including emphasizing ergonomic positions as well as psychological state de-escalation. It is expected that dentoalveolar surgery will contribute to the development of stomatology as a pioneering discipline in the field of comfortable treatment.

The widespread application of dental implant technology provides a new solution for patients with missing teeth. Particularly, the complete dentures supported by dental implants provides better chewing efficiency and aesthetics for patients. It has become a common pursuit of both dentists and patients with terminal dentition to achieve immediate implant-supported restorations and avoid suffering from missing teeth. In this article, the digital sequential guide techniques of immediate implant placement and restoration for patients with terminal dentition were summarized and reviewed, so as to provide reference for their clinical application.

Lingual nerve injury is one of the serious complications in alveolar surgery, which often occurs after the extraction of the mandibular third molar (M3M), with the incidence varying from 0.1% to 22%.Due to the limitations of clinical and conventional radiographical examinations, some severe cases do not receive accurate diagnosis and effective treatment in the early stage of injury, resulting in permanent lingual nerve injury and consequent impact on the quality of life. In recent years, magnetic resonance neurography (MRN) has been gradually used in the examination of nerve injury, and several new MRN sequences have reasonable visualization of severe lingual nerve injury, making early diagnosis and therapy possible. This article reported a patient with lingual nerve injury caused by the removal of M3M for 2 weeks, and complete disconnection of the affected lingual nerve was clearly visualized through MRN. Subsequently, a nerve anastomosis surgery was performed, and the disconnection was observed during the operation, proving the consistency of the MRN imaging and the fact. Postoperative follow-up showed gradually functional recovery of the lingual nerve.

After tooth extraction, significantly physiological atrophic changes would occur to the socket. In the aesthetic zone, the collapse of the labial/buccal bone contour could seriously affect the aesthetic outcome of implant-supported restorations. In order to preserve the labial bone, immediate implant placement has strict indications, which can hardly be met by the majority of patients. Herein, this article summarized the rule of atrophic changes in the labial/buccal bone of the extraction socket through literature review. Further, based on this biological rule and our research findings, the expanded indications, clinical surgical procedures, and bone substitutes used for immediate implant placement were reviewed.

Oral lichen planus (OLP) is a chronic inflammatory disease of oral mucosa with complex etiology, which belongs to the category of oral potential malignant disorders. At present, drug therapy is the main treatment of OLP. Although a variety of new immunosuppressive agents are widely used in OLP treatment, some cases are still difficult to treat and easy to relapse, and a few cases end up with malignant transformation. Exploring new therapeutic drugs and methods is the key to solve the current dilemma. With the development of modern biotechnology and medical equipment, the biological agents, photodynamic therapy and photobiomodulation therapy are gradually applied to the clinical treatment of OLP. This article reviews the recent literature and provides a brief overview of the treatment progress of OLP.

Probiotics participate in the regulation of various micro-ecosystems of the host and have the potential to treat a variety of diseases related to microecological imbalance. In recent years, some studies have found that probiotics have a good application prospect in the prevention and treatment of oral diseases, especially periodontal diseases, however, the potential of probiotics in the biomedical field has not been fully developed. This paper is to review the mechanism, effect, and application prospect of probiotics in the prevention and treatment of oral diseases, especially periodontal diseases and peri-implant diseases.