Maxillary cysts can be classified according to their tissue origin and site of origin. Those that evolve from the epithelium or epithelial remnants of adult tissues or teeth are called odontogenic jaw cysts. Cysts due to residual epithelium from the embryonic period and cysts of extravasated blood due to injury and aneurysmal bone cysts are called non-dental jaw cysts. They are all relatively rare clinically. Odontogenic cysts of the jaws occur mostly in young adults. They can occur in any part of the jaw. Root-end cysts mostly occur in the anterior teeth; primordial cysts and keratocysts tend to occur in the mandibular third molar area and mandibular branch; tooth-containing cysts, in addition to the mandibular third molar Ⅸ, also occur in the maxillary cuspid area. Odontogenic jaw cysts grow slowly and there are no conscious symptoms at the beginning. If it continues to grow, the bone gradually expands to the periphery and a facial deformity is formed. If the cyst grows to a larger size, the bone on the surface becomes a very thin bone plate, which can be felt like a ping-pong ball when palpated, with a so-called parchment-like brittle sound, and finally, when this very thin bone plate is also absorbed, a fluctuating sensation can occur. Since the bone plate on the buccal side of the jaw is generally thinner than on the lingual side, most of the cysts generally swell toward the buccal side; however, keratotic cysts may swell toward the lingual side in 1/3 of the cases and penetrate the lingual bone wall. When the mandibular cyst develops too large and the bone is damaged too much, it may cause pathological fracture. Cysts in the maxilla may invade the nasal cavity and maxillary sinus, pushing the inferior orbital rim upward, while compressing the eye and affecting vision, or even producing diplopia. If the adjacent teeth are compressed, periapical bone resorption can cause displacement, loosening and tilting of the teeth. Root-end cysts can be found in the oral cavity with deep caries, residual roots or dead pulp teeth. Beginning, contained and keratinized cysts may be associated with congenitally missing teeth or with additional teeth. If the cyst ruptures due to tooth extraction injury, a straw-yellow or straw-green fluid may be seen inside the cyst; in the case of keratotic cysts, a sebum-like substance may be seen. If the cyst is secondary to infection, inflammation occurs and the patient feels swelling, pain, fever, and general discomfort. With the exception of root-end cysts, all odontogenic cysts can transform into or be accompanied by the presence of enameloblastoma; keratotic cysts also have significant recurrence and carcinogenic capacity. Clinically, odontogenic jaw cysts can be solitary or multiple. Solitary cysts are usually the most common. When multiple keratotic cysts are accompanied by cutaneous basal cell nevus (or basal cell carcinoma), bifurcated ribs, widened orbital spacing, cranial abnormalities, and calcification of cerebellar sickle, it is called “nevus-like basal cell carcinoma syndrome” or “multiple basal cell nevus syndrome”. If there are only multiple keratocysts and no symptoms such as basal cell nevus (carcinoma), it can also be called keratocyst syndrome.