**10.5 Nerve damage**

*Current Treatment of Cleft Lip and Palate*

reported similar findings [71–73].

planted to become functional [74].

**10.3 Infection**

1–8% [76–78].

It is believed that maxillary advancement in cleft patients has a potential to worsen velopharyngeal function (VPF). Nevertheless, there is still no certain evidence on whether or not the amount of advancement affects velopharyngeal disorder and whether or not preoperative VPF is related to the postoperative outcome. It is most likely that improvements are seen in the articulation of patients after surgery due to the correction of dental arches [69]. In a systematic review of the complications that developed as a result of orthognathic surgery on cleft patients, Yamaguchi et al. [62] reported postoperative velopharyngeal deficiency (VPD) as 16.79%.

Moran et al. [70] examined 79 cleft patients who received treatments of conventional orthognathic surgery or distraction osteogenesis, and they reported that, following maxillary advancement rates from 3 to 11 mm, there was VPD in 5 (6.33%) cases. These five patients were also found to have borderline VPD preoperatively. The results of their study supported those of other studies that there is no relationship between maxillary advancement and the amount of postoperative velopharyngeal disorders [71], and when orthognathic surgery and total maxillary distraction are compared in terms of speech and VPD, there is no significant difference [71–73]. Additionally, the finding that there is no correlation between postoperative speech impediment and preoperative borderline VPD was added to the literature which

It is a difficult process to estimate soft tissue changes after orthognathic surgery

Infection rates following orthognathic surgery are highly variable due to reasons such as antibiotics usage styles and diagnostic differences [75, 76]. Recent studies on orthognathic surgery in individuals without clefts reported an incidence of less than

Miloro derived a few results by analyzing 15 previous studies on infections following orthognathic surgery: infection incidence may decrease in the case of using oral antibiotics for more than 1 day after surgery. First-generation cephalosporins are used more frequently before surgery. Mandibular osteotomy regions are where infections are seen the most. Extraction of the third molar may have a small effect on infection incidence, but this is under debate. Most infections that occur after orthognathic surgery are small, and removal of fixation plates and screws is rarely necessary [75]. In an analysis of the USA National Inpatient Samples Database (2012–2013), the rate of emergence for any kind of infectious complication following orthognathic surgery was reported as 7.4% in patients with a craniofacial anomaly and 0.6% in those without a craniofacial anomaly [78]. Recent studies reported rates of from 0to 13.92% for infections emerging after orthognathic surgery in cleft patients without any craniofacial anomaly [61, 62, 68, 70]. In the study that obtained a high rate of incidence as 13.92% despite 5 days of routine antibiotics usage, the authors emphasized the importance of oral hygiene, team collaboration, and patient cooperation [70].

Segmental maxillary osteotomies may have a risk of postoperative oronasal fistulae. In a systematic review in 2017, the postoperative fistula rate was reported

and prevent them. This is because the adaptation of the velopharyngeal region for compensation of other regions is variable, and it is dependent on the personal characteristics of each patient and the capacity of tissues that are present or trans-

**10.2 Speech impediment**

**74**

**10.4 Oronasal fistula**

The neural disorders that occur as a result of orthognathic surgery mainly affect the infraorbital, inferior alveolar (mandibular), and mental and incisive nerves. Reports on facial nerve paralysis vary in the range of 0.17–0.75% [81].

The incidence of continuation of inferior alveolar nerve disorders varies between 5 and 15% depending on the age of the patient and the technique that is used (piezo-surgery or conventional) [82, 83]. A systematic review in 2017 reported that usage of piezo-surgery in orthognathic operations was associated with significant reductions of loss of blood during surgery and severe nervous disorders [84].

In orthognathic surgery on cleft patients, 70% of the patients may experience paresthesia after surgery, and a permanent sensory disorder may occur in 25% [80]. Bhatia et al. [61] stated that all 25% of patients who experienced cheek paresthesia recovered after a year. Moran et al. [70] reported that the sensory neuropathy of the infraorbital nerve was temporary in 53% of patients and permanent in 1.27%. In addition to this, 3D computer-assisted planning and determination of the inferior alveolar nerve may contribute to the safety of orthognathic surgery [85].
