1.What are the commonly used materials for full crowns in restorative dentistry? What are the advantages of these materials in clinical use? What are the disadvantages? Suitable for restoring which position of the teeth? A: commonly used full crown materials for oral prosthetics are: ① metal porcelain (nickel-chromium alloy, cobalt-chromium alloy, titanium alloy, pure titanium, gold alloy, etc.); ② full porcelain crown (generally divided into glass-ceramic, low-purity aluminum porcelain, high-purity aluminum porcelain, zirconia); ③ metal crown (nickel-chromium alloy, cobalt-chromium alloy, titanium alloy, pure titanium, gold alloy, etc.). (1) porcelain crown: advantages: ① can restore the morphological function of the tooth; ② realistic appearance, smooth surface; ③ strong fracture resistance, wear resistance; ④ color stability; ⑤ good biocompatibility. (2) the advantages of all-ceramic crowns: stable natural color, low thermal conductivity, non-conductive, wear-resistant, good biocompatibility, no metal structure, impervious to metal color, is the more ideal restoration of the front teeth. Disadvantages: high price. (3) Advantages of metal crowns: strong retention, high strength of their own. Disadvantages: poor aesthetics. Metal porcelain crowns and all-porcelain crowns can be used for both front and back teeth, metal crowns are mainly used for back teeth. 2.What are the common methods of restoring individual missing teeth? What are the indications for each of them? A: The commonly used methods for individual tooth loss are: implant, fixed and movable restoration. (1) Indications for implant restoration: ① partial or individual tooth loss in the upper and lower jaw, adjacent teeth are not suitable for abutment teeth or to avoid damage to adjacent teeth; ② repair of missing molar or free end missing teeth; ③ full mouth loss, especially severe atrophy of the alveolar process of the mandible; ④ poor retention of the movable denture; ⑤ sufficient healthy bone and sufficient gingival attachment in the implant area; ⑥ unilateral or bilateral jaw bone loss due to tumor or trauma, need functional (6) unilateral or bilateral jaw bone defects caused by tumor or trauma, which need functional restoration. (2) Indications for fixed denture: suitable for a few missing teeth, good periodontium, the number and condition of abutment teeth can meet the support of retention can be considered fixed restoration. (3) Indications for movable denture: from single tooth loss to a wide range of maxillary and mandibular missing only a single tooth and even with soft and hard tissue loss can be used for movable restoration. 3.Which oral restoration method will cause the least damage to the adjacent teeth? A: Dental implant restoration has no damage to the adjacent teeth. 4. From the perspective of comfort and practicality, which restorative material is the best in combination with which restoration method? From the aesthetic point of view, which material is best for which restoration method? A: Dental implant + all-ceramic crown restoration is considered to be the ideal restoration method and the development direction of oral restoration. If you can’t do dental implant restoration, fixed denture restoration is also a more comfortable and beautiful restoration method. 5.What is the process of oral restoration? Do I have to take pictures? How long does it usually take to complete the restoration? How many times do I have to visit the clinic during the process? A: You should first ask the patient’s intention and then check the patient’s teeth to see what kind of restoration is suitable. The general process of restorative dentistry is: diagnosis → design → dental preparation → model taking → denture making → tooth wearing. The restoration does not necessarily need to be photographed, but it is necessary to do so for implants or pile cores. Fixed and removable dentures generally take 1-2 weeks to complete and are completed in 2-3 visits. Implants take longer, usually 3-6 months, 2-3 times to complete. 6.What is all-ceramic crown? What is the difference with porcelain crowns? Which type of patients are suitable for all-porcelain crowns? A: All-porcelain crown is a restoration made of ceramic material covering the entire surface of the crown. Compared to metal porcelain, it does not require a metal structure, impervious to metal color, processing is relatively simple, is a more ideal restoration of the front teeth. Compared with metal porcelain crowns, the color of all-porcelain teeth can maintain the natural color whether in the light or in natural light. All-porcelain teeth are composed entirely of porcelain powder, the color and layers are maximized, better durability, can be permanently preserved in the mouth, no metal base, light weight, no irritation to the gums, more comfortable to wear, low thermal conductivity, more conducive to the protection of pulpal health; reflection and scattering of light is closer to natural teeth, with better aesthetic effect. However, the price is higher and more dental tissue needs to be removed. All-porcelain crowns are suitable for front teeth incisal angle, incisal edge defect, can not be filled or should not choose metal crowns or metal porcelain restoration, and then is the high aesthetic requirements. 7.What materials are used for all-ceramic crowns? What damage to adjacent teeth? A: All-porcelain crown materials are generally glass ceramic, low-purity aluminum porcelain, high-purity aluminum porcelain, zirconia, etc.; glass ceramic is generally used in porcelain veneers, zirconia is generally used in full crowns. Regular operation will not cause harm to neighboring teeth.