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Introduction: Surgery of the midface for non-syndromic patients with maxillo-malar hypoplasia exclusively has had many breakthroughs lately. The surgical techniques for midface surgery are varied and must be selected according to the patient's problem. Purpose: The technique is a modification of the Z Osteotomy, the Modified Anterior Z Le Fort III Osteotomy (MAZLFIIIO), is used to correct posteroanterior midface deficiency of 6 mm at most. It can be combined simultaneously with a Le Fort I osteotomy if a greater maxillary advance is needed. MAZLFIIIO advances midface without grafts or distraction osteogenesis. The anterior reposition of the midface is calculated in millimetres and depends on the relation of the eye's most inferior point, as well as the orbital's hard and soft tissues. It is a predictable osteotomy, only for patients without vertical excess of the midface. The osteotomy planned is drawn over a stereolithographic model, and then Z-shaped surgical splints are fabricated over it. Transverse midface deficiencies of no more than 4 mm can also be corrected during the malar osteotomy. A great number of patients are operated exclusively with Le Fort I osteotomies, leaving behind an undesirable step between the upper part of the midface and the Le Fort I osteotomy. Methods: The Modified anterior Z Le Fort III Osteotomy (MAZLFIIIO) was performed in seven patients, from 2016 to 2018. Results: The results obtained with the proposed osteotomy notably improve the appearance of the patient and provide a better protection of the lower part of the eye, while widening the maxillary sinus. Conclusion: We consider that maxillo-malar hypoplasias are very common; the surgeon pretends not to give importance to the deformity, exclusively using an advance Le Fort type osteotomy, with both functional and aesthetic treatment being limited. In this article, we give all the elements to perform this Le Fort III Modified Osteotomy in anterior Z, and that it is a combined and routine procedure in midface surgery.

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Patients with syndromic and nonsyndromic synostosis may have end-stage skeletal discrepancies involving the lower midface and mandible, with associated malocclusion. While orthognathic surgical procedures in this population can be reliably executed, the surgeon must be aware of the unique morphologic characteristics that accompany the primary diagnoses as well as the technical challenges associated with performing Le Fort I osteotomies in patients who have undergone prior subcranial midface distraction.

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Patients with a skeletal Class III deformity may present with a concave contour of the anteromedial cheek region. Le Fort I maxillary advancement and rotational movements correct the problem but information on the impact on the anteromedial cheek soft tissue change has been insufficient to date. This three-dimensional (3D) imaging-assisted study assessed the effect of surgical maxillary advancement and clockwise rotational movements on the anteromedial cheek soft tissue change. Two-week preoperative and 6-month postoperative cone-beam computed tomography scans were obtained from 48 consecutive patients who received 3D-guided two-jaw orthognathic surgery for the correction of Class III malocclusion associated with a midface deficiency and concave facial profile. Postoperative 3D facial bone and soft tissue models were superimposed on the corresponding preoperative models. The region of interest at the anteromedial cheek area was defined. The 3D cheek volumetric change (mm3; postoperative minus preoperative models) and the preoperative surface area (mm2) were computed to estimate the average sagittal movement (mm). The 3D cheek mass position from orthognathic surgery-treated patients was compared with published 3D normative data. Surgical maxillary advancement (all p < 0.001) and maxillary rotation (all p < 0.006) had a significant effect on the 3D anteromedial cheek soft tissue change. In total, 78.9%, 78.8%, and 78.8% of the variation in the cheek soft tissue sagittal movement was explained by the variation in the maxillary advancement and rotation movements for the right, left, and total cheek regions, respectively. The multiple linear regression models defined ratio values (relationship) between the 3D cheek soft tissue sagittal movement and maxillary bone advancement and rotational movements of 0.627 and 0.070, respectively. Maxillary advancements of 3-4 mm and >4 mm resulted in a 3D cheek mass position (1.91 ± 0.53 mm and 2.36 ± 0.72 mm, respectively) similar (all p > 0.05) to the 3D norm value (2.15 ± 1.2 mm). This study showed that both Le Fort I maxillary advancement and rotational movements affect the anteromedial cheek soft tissue change, with the maxillary advancement movement presenting a larger effect on the cheek soft tissue movement than the maxillary rotational movement. These findings can be applied in future multidisciplinary-based decision-making processes for planning and executing orthognathic surgery.

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INTRODUCTION: Various surgical modalities have been proposed for the augmentation of midface deficiency without correction of the occlusal component. They include autogenous bone and cartilage grafts, alloplastic materials, and osteotomies. We propose an innovative osteotomy technique for augmentation of the midface including the infraorbital rims, the zygoma, the anterior maxillae, and the paranasal areas without advancing the dental-bearing segment. MATERIALS AND METHODS: This procedure was carried out on a 21-year-old male patient who had a deficiency of the anterior maxillae including the infraorbital rims. His occlusion was in Class I molar relation. The surgical exposure was carried out through a midface degloving approach. This bilateral osteotomy encompasses the anterior maxillae and the zygoma; the osteotomy line running superiorly from the medial aspect of the infra-orbital rim to the root of the frontal process of maxilla. Inferiorly, the line runs above the apices of the maxillary teeth laterally underneath the zygomatic buttress, separating part of the zygomaticomaxillary suture posteriorly. Medially, the osteotomy line runs parallel to the piriform aperture. The osteotomy is pedicled on the zygomaticotemporal suture. A greenstick fracture at the zygomatic arch pedicled the osteotomized segment to the zygomatic process of the temporal bone. The entire segment was swung laterally outward, effectively separating part of the zygomaticomaxillary suture posteriorly. Fixation was achieved with a single 2-mm L-shaped, 4-hole plate with gap at the zygomatic buttress region. RESULTS: This osteotomy technique resulted in fullness of the anterior maxillae and infraorbital rims, with increased anterior and lateral projection of the zygoma. CONCLUSION: The zygomaticomaxillary "lateral swing" osteotomy is a reliable and stable technique for total midface augmentation not requiring occlusion correction.

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OBJECTIVE: This study examined cone-beam computed tomography (CBCT)-derived multiplanar-reconstructed (MPR) cross-sections to clarify the salient characteristics of patients with skeletal class III malocclusion with midface deficiency (MD). METHODS: The horizontal and sagittal plane intersection points were identified for middle-third facial analysis in 40 patients in the MD or normal (N) groups. MPR images acquired parallel to each horizontal plane were used for length and angular measurements. RESULTS: A comparison of the MD and N groups revealed significant differences in the zygoma prominence among female patients. The convex zygomatic area in the N group was larger than that in the MD group, and the inferior part of the midface in the N group was smaller than that in the MD group for both male and female patients. A significant difference was observed in the concave middle maxillary area among male patients. CONCLUSIONS: This study was conducted to demonstrate the difference between MD and normal face through MPR images derived from CBCT. Male patients in the MD group had a more flattened face than did those in the N group. Female patients in the MD group showed a concave-shaped lower section of the zygoma, which tended to have more severe MD. These findings indicate that orthognathic surgery to improve skeletal discrepancy requires different approaches in male and female patients.

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OBJECTIVE: This study examined cone-beam computed tomography (CBCT)-derived multiplanar-reconstructed (MPR) cross-sections to clarify the salient characteristics of patients with skeletal class III malocclusion with midface deficiency (MD). METHODS: The horizontal and sagittal plane intersection points were identified for middle-third facial analysis in 40 patients in the MD or normal (N) groups. MPR images acquired parallel to each horizontal plane were used for length and angular measurements. RESULTS: A comparison of the MD and N groups revealed significant differences in the zygoma prominence among female patients. The convex zygomatic area in the N group was larger than that in the MD group, and the inferior part of the midface in the N group was smaller than that in the MD group for both male and female patients. A significant difference was observed in the concave middle maxillary area among male patients. CONCLUSIONS: This study was conducted to demonstrate the difference between MD and normal face through MPR images derived from CBCT. Male patients in the MD group had a more flattened face than did those in the N group. Female patients in the MD group showed a concave-shaped lower section of the zygoma, which tended to have more severe MD. These findings indicate that orthognathic surgery to improve skeletal discrepancy requires different approaches in male and female patients.

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Skeletal deficiency in the central midface impacts nasal aesthetics. This lack of lower face projection can be corrected by alloplastic augmentation of the pyriform aperture. Creating convexity in the deficient midface will make the nose seem less prominent. Augmentation of the pyriform aperture is, therefore, often a useful adjunct during the rhinoplasty procedure. Augmenting the skeleton in this area can alter the projection of the nasal base, the nasolabial angle, and the vertical plane of the lip. The implant design and surgical techniques described here are extensions of others' previous efforts to improve paranasal aesthetics.

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OBJECTIVE: To evaluate the horizontal and vertical stability of the quadrangular Le Fort I in patients with congenital cleft lip and palate. DESIGN: Prospective longitudinal study. PATIENTS: A total of 15 congenital cleft lip and palate patients treated with the maxillary quadrangular Le Fort I were enrolled. INTERVENTION: Lateral cephalometric radiographic examinations were obtained preoperatively, early postoperatively, and late postoperatively for four dental and skeletal landmarks. A questionnaire regarding patients' satisfaction with treatment and functional/cosmetic outcomes (airway, speech, mastication) was administered. MAIN OUTCOME MEASURES: Surgical horizontal and vertical movement, late postsurgical horizontal and vertical movement, and surgical and postsurgical movement in relation to age and cleft type were evaluated using Spearman correlation coefficients, Wilcoxon signed rank tests, and Mann-Whitney tests. RESULTS: Surgical horizontal movements of all measured points showed significant changes. Significant differences of postsurgical horizontal movement were observed in younger patients versus adult patients. Significant differences of postsurgical horizontal movement were observed in unilateral cleft patients versus bilateral cleft patients. A high percentage of patients showed significant functional improvement in nasal airflow, speech, mastication, temporomandibular joint function, and mouth versus nose breathing. CONCLUSIONS: The quadrangular Le Fort I is a functionally stable and a surgically predictable procedure for cleft lip and palate patients who present with midface deficiency. Patients under the age of 18 at the time of the osteotomy had a higher relapse rate than patients over 18 years of age. Younger patients who need surgery should be advised regarding the increased risk of skeletal relapse. Patients' satisfaction was high in all aesthetic- and function-related items on the questionnaire.

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