Resin, generally referred to clinically as composite resin, is a filling material commonly used in dentistry. Its advantages include good biocompatibility, aesthetics, high hardness, etc.; disadvantages include polymerization and shrinkage, and irritation to the pulp. 1.Advantages: (1) Good biocompatibility: composite resin is odorless, non-toxic and non-irritating, with good biocompatibility and no obvious irritation to the surrounding tissues. (2) Aesthetics: composite resin color is close to the tooth, and there are a variety of different colors to choose from, which can be matched with the color of the restored tooth or neighboring teeth to achieve the role of aesthetics. (3) High hardness: composite resin has high hardness, wear resistance, can withstand a certain chewing pressure, not easy to produce disintegration phenomenon. 2.Disadvantages: (1) Polymerization and contraction: composite resin has polymerization and contraction phenomenon after exposure to light, which makes micro-leakage occur between filling and tooth, and secondary caries is easy to occur. (2) Stimulation of the pulp: composite resin can stimulate the pulp when filling near-pulpal caries, the principle of which is not certain. Clinically, it is often used to minimize the irritation to the pulp by filling the bottom of the cavity. If you have dental discomfort, please consult the doctor in time, complete the examination, and standardize the treatment under the guidance of a professional physician to avoid delaying the condition.