1, pulpitis overview Pulpitis is a common dental pulp disease, mainly caused by infection from the body of the tooth. Pain is the main characteristic of pulpitis, such as acute pulpitis attack, will be manifested as a severe unbearable pain, the proverbial “toothache is not a disease, the pain is killing me” refers to this course of disease. This is due to the fact that the pulp tissue is inside the hard tooth and inflammatory exudate is not easily drained, causing the pulp cavity to increase in pressure and compress the nerve. Because of this, most pulp inflammation cannot be eliminated on its own and requires external means to relieve pain, remove the infection, and eliminate avenues for reinfection. The modern treatment of pulpitis has evolved around this core of thinking. 2, the preferred treatment option for pulpitis – root canal therapy Currently, the most widely used clinical method for the treatment of pulpitis is root canal therapy, which is also internationally recognized as the most effective treatment for pulpitis. The principle is to prepare the root canal by mechanical debridement and chemical disinfection, remove the infected material from the pulp cavity, and fill it tightly to prevent reinfection. Since the 1980s, with the maturation of endodontic techniques and improvement of instruments, together with the introduction of new materials and the application of various modern techniques in treatment (e.g., oral microscope assisted system and ultrasound technology), the clinical success rate of endodontic treatment has been greatly improved, and therefore it is also called modern endodontic treatment. Compared with other treatments, the complexity of root canal treatment is higher, not only does it require perfect preparation before treatment, but also all aspects of root canal treatment (root canal preparation and shaping, cleaning and disinfection of root canal contents, filling and sealing of root canal) must be controlled in a standardized and strict manner in order to achieve the ideal treatment effect. 2004, the Endodontic Special Committee of the Chinese Society of Stomatology formulated “National technical specification and quality control standard for root canal treatment”, which became the technical standard that should be followed by dentists in China. 3. Dry pulp surgery and pulp plastination treatment Due to the complexity of the pulp cavity anatomy, the technical sensitivity of root canal treatment and the imbalance of the development status of oral medicine in different places, sometimes it is difficult for us to use root canal treatment to treat pulpitis. In other words, sometimes we have to leave part of the infected material in the pulp cavity. In such cases, there are ways to “render harmless” the infected material, mainly dry pulp and pulp plastination. Pulpotomy is an early method of treating pulpitis with a “harmless” mindset, based on removing the infected crown pulp and drying the root pulp with a drug (paraformaldehyde). Although it is still used in some primary dentistry, its long-term clinical efficacy is far inferior to that of endodontics, and due to its high failure rate and the toxic side effects of formaldehyde, endodontists should be aware of it, use it with caution, and eventually phase it out. The principle of endodontic plasticization treatment is to introduce an unpolymerized liquid plasticizer (phenolic resin) into the root canal where most of the pulp has been extracted, and when the plasticizer polymerizes it will encapsulate and plasticize the remaining pulp and infected material in the root canal as one, and keep it sterile and become harmless to the organism. However, due to some objective problems, such as residual unpolymerized plasticizer, lack of objective operational indications, and difficulties in retreatment of root canals after plasticization, plasticization treatment was gradually replaced by root canal treatment. In some cases, we can preserve a part of the pulp tissue that has not suffered from infection. For example, for young permanent teeth with only partial crown pulp infection, the crown pulp is removed under local anesthesia and the pulp section is covered with pulp capping agent (calcium hydroxide) to preserve the normal pulp of the root, which is called calcium hydroxide live pulpotomy. In recent years, with the development of molecular biology and tissue engineering, the study of pulp reconstruction has become a hot direction in the future research of pulpitis treatment.