Palatal fistula is traditionally considered to be the presence of abnormal communication between the oral and nasal cavities in patients with cleft palate after surgery. One of the key principles of successful cleft palate surgery is to separate the soft tissues on the lateral side of the oronasal cavity, form the lining of the oronasal cavity at the cleft, suture them relative to each other, reconstruct the normal anatomical level of the palate and separate the oral and nasal cavities. And the cleft of the wound between the uvula and the alveolar ridge occurs, resulting in a cleft palate. With the large number of charitable organizations entering the field of cleft lip and palate treatment, a large number of stage I cleft lip and palate surgeries are performed by non-specialized cleft lip and palate surgeons who do not understand the developmental patterns of children with cleft lip and palate and often suffer from postoperative palatal leakage. Large palatal fistulas can cause complications such as voice dysfunction, poor nasal oral hygiene, hearing impairment, and psychological disorders in patients. The incidence of early palatal fistulas is high and has gradually decreased as surgical techniques have improved. Children with palatal leakage tend to have less facial recession, which also has some benefit. Treatment overview The primary palate consists of the hard and soft tissues before the line between the incisal foramen and the cuspid (alveolar ridge, premaxilla, pyriform foramen, and upper lip); the secondary palate consists of the hard and soft tissues after the line between the incisal foramen and the cuspid and between the uvula, including the maxilla, alveolar ridge, hard and soft palate. A simple cleft palate involving the hard and soft palate (not affecting the alveolar ridge) can be described as a complete secondary cleft palate, whereas a cleft palate involving only the soft palate (not affecting the hard palate or alveolar ridge) can be described as an incomplete secondary cleft palate. Bony maxillary/alveolar crest cleft and oronasal vestibular fistula. Many practitioners consider this to be part of the primary alveolar bone defect that has been deliberately omitted during surgery, rather than a true unrepaired “fistula”. The ideal surgical treatment for a child with a complete cleft palate requires closure of the hard and soft palate (secondary palate) cleft in infancy, followed by reconstruction of the maxillary/alveolar ridge (primary palate) cleft with bone grafting in adolescence, including repair of the oronasal vestibular fistula. Surgical repair of palatal leaks is divided into three generations, with most hospitals now using second-generation techniques. The current applications include local palatal flap repair, modified von Langenbeck and two-flap cleft palate repair, cleft palate repair combined with a posterior pharyngeal wall flap, and the application of the lingual flap method for fistula repair. Other local flaps include: lingual mucosal flap, buccal mucosal flap, temporalis muscle flap, and vascularized tissue flap. The most common method of palatal fistula repair is to use a local soft tissue flap of the palate, rotated to cover the palatal fistula. Surgical steps: preparation of a flap around the fistula to close the nasal fistula; stripping and preparation of a palatal finger flap and rotation of the tissue flap to cover and close the fistula. A large area of the donor area is exposed to the bone surface, allowing for second-stage healing. However, this method can only be used for small palatal fistula repairs and has a fairly high failure rate. In palates with extensive scar tissue and no tension, the mobility of small rotating flaps is poor and the blood supply may be limited, leading to decreased healing ability and thus recurrent fissures. In the presence of a large palatal fistula (>37.5 px), successful closure of the fistula requires that the adjacent flap be supplemented with adequate soft tissue. Palatal fistulas between the posterior border of the hard palate and the soft palate can be closed with a modified cleft palate repair combined with a posterior pharyngeal wall flap with the tip above. The posterior pharyngeal wall flap is prepared by turning up the mucoperiosteal flap of the palate and peeling off the mucoperiosteal flap of the nasal side. By applying this method, sufficient tissue volume can be replenished to close the large palatal fistula without tension. When the palatal fistula is located in the anterior 2/3 of the hard palate, a dorsal lingual mucosal flap with an anterior tip may be used. The second generation palatal leak repair technique is less technical and only aims to close the leak. After repair, the palatal leak is replaced by a large scar, which limits further development. Nowadays, the latest technology is the third generation palatal leak repair technology, which is very technically advanced. The third generation palatal leak repair technique focuses on the patient’s original tissue repositioning and presents a new theory of the palatal leak. There is no tissue loss in a palatal leak, only a displacement of tissue. The palatal leak can be repaired by repositioning the tissues. Also, bone grafting and bone forming protein implantation can be assisted to restore the bone connection of the palatal leak.