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Inferior positioning of the maxilla by a Le Fort I osteotomy: a review of 25 patients with vertical maxillary deficiency.

In 25 patients with vertical maxillary deficiency, selected for a group of 410 Le Fort I osteotomies, the anterior part of the maxilla was repositioned inferiorly. Four groups could be distinguished. A group (n = 6) with downgrafting of the maxilla alone, fixed with wire osteosynthesis, a group (n = 6) treated with Le Fort I and sagittal split osteotomy with a wire-fixed maxilla, a group (n = 8) with a Le Fort I and vertical ramus osteotomy where the maxilla was fixed with wire and group (n = 5) treated by Le Fort I and vertical ramus osteotomy in which the maxilla had been fixed with miniplate osteosynthesis. In the group of single maxilla repositioning and in bimaxillary group with a plate-fixed maxilla, the range of relapse was -0.3 mm to +1.0 mm (mean + 0.4 mm) and 0 mm to + 1.0 mm (mean + 0.5 mm) respectively, which was not correlated to the distance of inferior repositioning. The bimaxillary cases, in which the maxilla had wire osteosynthesis, showed postoperative relapse ranging from - 1.4 mm to + 3.4 mm (mean + 1.3 mm) (sagittal split osteotomy) and - 1.1 mm to + 3.7 mm (mean + 1.2 mm) (vertical ramus osteotomy). In these cases the outcome of surgical intervention appeared completely unpredictable. If these figures are presented as percentages as is done in the literature in the majority of publications, a misleading impression appears. Likewise information about operation technique, fixation methods and linear measurements of movement and relapse (instead of percentages) are essential in comparing different studies.

Adult↗

Post-operative stability of the maxilla treated with Le Fort I and horseshoe osteotomies in bimaxillary surgery.

In this study, the post-operative change of the maxilla in six non-cleft patients who underwent combination (Le Fort I and horseshoe) osteotomy for superior repositioning of the maxilla was investigated. In all patients, the maxilla was first osteotomized and fixed with four Luhr plates. No iliac bone graft was applied to the maxilla. A bilateral sagittal split ramus osteotomy of the mandible (BSSRO) was then carried out and titanium screw fixation was performed. No maxillo-mandibular fixation (MMF) with stainless steel wire was used post-operatively in any patient. Lateral cephalograms were obtained pre-operatively, 5 days post-operatively, and 3, 6, and 12 months after surgery. The changes in anterior nasal spine (ANS), point A, upper incisor (U1), and point of maxillary tuberosity (PMT) were examined. The maxillae in the six subjects were repositioned nearly in their planned positions during surgery and no significant post-operative changes in the examined points of the maxilla were found. These results suggest that a combination of a Le Fort I and horseshoe osteotomy is a useful technique for reliable superior repositioning of the maxilla. The post-operative change in the maxilla using this combination osteotomy is comparatively stable.

Adult↗

The thickness and the lengths of the anterior wall of adult maxilla of the West Anatolian Turkish people.

The maxilla is the key structure on facial formation and stability. The knowledge about maxillary thickness and dimensions is crucial during facial reconstruction including this bone. In this study, anthropometric measurements of anterior wall of the maxilla on the dry human skulls were aimed. Sixty maxillae of 30 adult dry skulls of West Anatolian people were evaluated. Four vertical lines were drawn between the piriform aperture and lateral border of the bone and six horizontal lines between the infra-orbital margin and the inferior border of the piriform aperture. After establishing the lines, maxillary thicknesses on the intersection points of the vertical and horizontal lines and the lengths of the vertical lines from the infra-orbital margin to alveolar arch were measured by using a fine caliper. It was found that the thickest point of the anterior wall of the maxillae is on the lateral of the infra-orbital margin (5.17 +/- 2.27 mm), and thinnest one is on the inferior of the infra-orbital foramen (0.92 +/- 1.06 mm). The length of the vertical line tangent to piriform aperture (47.66 +/- 3.61 mm) is the longest. The corresponding data of the left and right maxillae were compared by Student's t test. There was no significant difference between both sides. After collecting the data, a thickness map of anterior wall of the maxilla was drawn. This data may be helpful in clinic during osteotomies, bone reconstructions, screw, or other reconstruction apparatus applications on the maxilla.

Adult↗

[Endoscopically-assisted LeFort I osteotomy in distraction procedures of the maxilla].

PURPOSE: The purpose of this study was to demonstrate the feasibility of combining a minimally invasive endoscopic approach to the maxilla with transverse and sagittal distraction procedures. MATERIALS AND METHODS: Four human cadavers were used for training of a minimally invasive access to the maxilla to perform an endoscopically assisted Le Fort I osteotomy, before this technique was applied in three patients with transverse and sagittal growth deficits of the maxilla. Access to the maxilla was gained through a small mucosa incision in the vestibule to create a visualization port to the maxillary sinus through a bur hole. Landmarks were identified through the endoscope before a Le Fort I osteotomy was performed using straight and angulated chisels of different form and angulation. In two patients, the maxilla was split sagittally to perform a transverse maxillary expansion. In one patient, a buried distractor was applied close to the piriform aperture to correct a sagittal growth deficit in a hypoplastic maxilla. RESULTS: The endoscopic exposure of the maxillary sinus walls from within the sinus, the accurate identification of landmarks, and the creation of a Le Fort I osteotomy was achieved in all cases. Distractor application close to the piriform aperture rendered good stability. CONCLUSION: The results of these case reports indicate that the endoscopic approach to the maxillary sinus allows excellent exposure of the sinus walls to perform an endoscopically assisted Le Fort I osteotomy. The combination of endoscopy and osteodistraction supports the trend toward minimally invasive, less traumatic surgical procedures, especially in individuals still growing.

Adolescent↗

Stability following superior repositioning of the maxilla by LeFort I osteotomy.

Cephalometric data from 61 patients who had undergone superior repositioning of the maxilla via LeFort I osteotomy by means of the downfracture technique were analyzed to evaluate stability of skeletal and dental landmarks at various time intervals up to 1 year. None of these patients had concurrent mandibular ramus or body osteotomy except genioplasty and all had at least 2 mm intrusion at the maxillary incisor or molar. In approximately 20% of the patients, there was 2 mm (critical value) or more postsurgical movement of skeletal or dental landmarks. During the first 6 weeks postoperatively, the maxilla showed a strong tendency to move farther upward in the patients in whom it was not stable. The posterior maxilla was vertically stable in 90% of the patients, the anterior maxilla in 80%. Horizontally, skeletal landmarks were stable in 80%, but when changes occurred, there was a tendency for the anterior maxilla to move back when it had been advanced. After the first 6 weeks, the posterior maxilla was stable vertically in all patients, but in 20% anterior maxillary landmarks moved downward, opposite to the direction of movement during fixation. In 11 of the 15 patients who demonstrated vertical changes postsurgery, the movement from fixation release to 1 year follow-up was opposite and approximately equal to the initial change, so that the net movement after 1 year was less than 2 mm. Only 6.5% (four patients) demonstrated 2 mm or greater net vertical movement for any of the variables studied 1 year after surgical treatment. There was no indication that the amount of presurgical orthodontic movement of incisors, the presence of multiple segments at surgery, the age of the patient, the presence or absence of genioplasty, or the presence or absence of suspension wires was a risk factor for instability.

Adolescent↗

The effects of a modified protraction headgear on maxilla.

Protraction headgears are commonly used in the treatment of Class III malocclusion characterized by maxillary retrognathism. The upward and forward rotation of the maxilla during protraction is a major unwanted side effect. The aim of this study was to eliminate the upward and forward rotation of maxilla while protracting. Seventeen patients with Class III malocclusion as a result of maxillary retrognathism were treated for 3 months; their average age was 12.81 years. A full coverage acrylic cap splint-type rapid maxillary expansion appliance was cemented and activated twice a day for 5 days. After sutural separation, a maxillary modified protraction headgear was worn and 750 g of force was applied. Wilcoxon signed rank test was carried out to evaluate 42 parameters measured on cephalometric radiographs. The maxilla was displaced anteriorly by downward and backward rotation. The mandible was displaced downward and backward due to anterior elongation of the maxilla. Extrusion and lingual tipping of the upper incisors and intrusion of upper molars and downward and backward rotation of functional occlusal plane were observed. The aim of our study was achieved, which was to avoid upward and forward rotation while protracting the maxilla. In conclusion, maxillary modified protraction headgear (MMPH) can be used effectively in Class III patients with retrognathic maxilla and anterior open bite tendency.

Adolescent↗

Endoscopically assisted Le Fort I osteotomy to correct transverse and sagittal discrepancies of the maxilla.

PURPOSE: The purpose of this report was to show the feasibility of the combination of a minimally invasive endoscopic approach to the maxilla with transverse and sagittal distraction procedures. MATERIALS AND METHODS: Four human cadavers were used for training of a minimally invasive access to the maxilla to perform a endoscopically assisted Le Fort I osteotomy, before this technique was applied in 3 patients with transverse and sagittal growth deficits of the maxilla. Access to the maxilla was gained through a small mucosa incision in the vestibule to create a visualization port to the maxillary sinus through a bur hole. Landmarks were identified through the endoscope before a Le Fort I osteotomy was performed using chisels of different shapes and angulations. In 2 patients the maxilla was split sagittally to perform a transverse maxillary expansion; in 1 patient, a buried distractor was applied close to the piriform aperture to correct a sagittal growth deficit in a hypoplastic maxilla. RESULTS: Endoscopic exposure of the maxillary sinus walls from within the sinus, the accurate identification of landmarks, and the creation of a Le Fort I osteotomy were achieved in all cases. Distractor application close to the piriform aperture rendered good stability. CONCLUSION: The results of these cases indicate that the endoscopic approach to the maxillary sinus allows excellent exposure of the sinus walls to perform a endscopically assisted Le Fort I osteotomy. The combination of endoscopy and osteodistraction processes supports the tendency to perform minimally invasive, less-traumatizing surgical procedures, especially in individuals who are still growing.

Adolescent↗

Reconstruction of the severely resorbed maxilla with autogenous bone, platelet-rich plasma, and implants: 1-year results of a controlled prospective 5-year study.

BACKGROUND: Prosthetic treatment of the edentulous maxilla may require bone augmentation to enable placement and integration of dental implants. This constitutes a complex healing situation, and resorption of the grafted bone and failure of the implants often occur. The application of autogenous platelet-rich plasma (PRP) has been suggested to improve incorporation and preservation of bone grafts. PURPOSE: The aim of this controlled clinical study was to evaluate whether PRP in conjunction with grafting of particulated autogenous bone to the maxilla could improve the integration and clinical function of dental implants. An additional aim was to compare block bone grafts without PRP with PRP-treated particulated bone. MATERIAL AND METHODS: Nineteen consecutive patients were included in the study and treated with iliac bone grafts and dental implants in the maxilla according to a split-mouth design. In the anterior maxilla, particulated bone mixed with PRP (test) was compared with onlay block grafts without additional PRP (control). In the posterior maxilla, particulated bone grafts with (test) or without (control) PRP were placed as sinus inlay grafts. After 6 months of healing, 152 implants (8 implants/patient) (TiOblast, Astra Tech AB, Mölndal, Sweden) were placed. Test (PRP; 76 implants) and non-PRP (76 implants) sides were evaluated and compared by implant survival rate, marginal bone level, and implant stability using resonance frequency analysis (RFA) during 1 year in function. RESULTS: Two control implants in control sites in two patients were lost at abutment connection. After 1 year in function, no further implants were lost, giving an overall survival rate of 98.7%. The marginal bone level measurements showed no significant differences, although there was a tendency toward less resorption on PRP sides. RFA measurements showed statistically significantly higher implant stability quotient values for PRP sites at abutment connection in the anterior but not in the posterior regions. CONCLUSIONS: The present clinical study showed that a high implant survival rate and stable marginal bone conditions can be achieved after 1 year of loading in the maxilla following autogenous bone grafting whether or not PRP is used. RFA measurements revealed differences at abutment connection, which could be explained by the type of graft rather than as an effect of PRP. Although no obvious positive effects of PRP on bone graft healing could be demonstrated, the handling of the particulated bone grafts was improved.

Adult↗

Prenatal growth pattern of the human maxilla.

Regarding maxillofacial morphogenesis there has been a long debate on the growth of the maxillary structure. Using 120 normal fetal maxillae of gestational ages from 16 to 41 weeks, palatal radiograms and frontal histologic sections were made. We have observed two pairs of accentuated growth areas in the fetal maxillae and named them primary growth centers to formulate the maxillary trapezoid (MT) by radiologic image. The MT is formed by four primary growth centers that are best demonstrated by palatal radiograms of the fetal maxilla as well as by frontal histologic sections. The dimensional increase in the MT during the fetal period is documented and statistically analyzed. From this series of results, we have suggested that the growth centers which demarcate the MT are the basic structures of the developing human maxilla. It was also found that the four primary growth centers are the most active sites for maxilla formation until 20 weeks of gestation and thereafter the growth of the maxilla is enhanced by the participation of the intramembranous bone formation along the periphery. This was in contrast to the central primary growth centers that have already finished maturation in the early fetal period and remain only as a peripherally radiating arrangement of thick trabecular bones.

Bone Development↗

Comparison between two experimental protocols to promote osteoporosis in the maxilla and proximal tibia of female rats.

The effects of two experimental protocols (ovariectomy associated or not with a low calcium diet) used to promote osteoporosis in the rat maxilla and proximal tibia were compared 5 and 11 weeks after surgery. Female Wistar rats were ovariectomized or sham-operated. Half of the ovariectomized rats were fed a low Ca++ diet (ovx*) and the remaining ovariectomized (ovx) and sham animals received a standard chow. At sacrifice, the proximal metaphysis was excised from the tibia and the molars were extracted from the hemi-maxilla. Dry (60 degrees C overnight) and ash (700 degrees C/14 h) weights were measured and the ashes were used for Ca++ measurement by means of a colorimetric method. After 5 weeks, ovx caused no alteration while ovx* decreased proximal metaphysis (17%) and maxilla (35%) bone mass. After 11 weeks, ovx caused a 14% bone mass reduction in the proximal metaphysis but not in the maxilla, while ovx* caused a comparable bone mass reduction (30%) in both bone segments. Calcium concentration was not altered in any experimental condition. The results show that estrogen deficiency is insufficient to cause maxillary osteoporosis in rats over an 11-week period and a long-term ovariectomy is needed to exert deleterious effect on proximal metaphysis bone mass. When a low Ca++ diet is associated with estrogen deficiency, however, a relatively precocious harmful effect is observed, twice as pronounced in the maxilla than in the proximal metaphysis. On a long-term basis, ovariectomy associated with a low Ca++ diet seems to be equally injurious to both proximal metaphysis and maxilla.

Alveolar Bone Loss↗

Surgically assisted-rapid orthopedic lengthening of the maxilla in primates--relapse following distraction osteogenesis.

A recent study has shown that the maxilla in primates can be successfully lengthened (0.5 mm every other day up to 6.0 mm) by means of surgically assisted-rapid orthopedic movement, using the principles of distraction osteogenesis. The present study was designed to determine if the maxilla can be advanced at a faster rate and if relapse would occur after removal of the orthodontic appliance. Metallic markers were placed in the cranial base and maxilla of two Cynomolgus primates, and cephalometric radiographs were taken. Bilateral horizontal and interdental osteotomies were created between in the first premolars and the canines, and the anterior segment was completely mobilized. An orthodontic appliance was bonded to the teeth and the screw was closed, compressing the osteotomy site. One week postoperatively the appliance was opened four quarter turns every day until the anterior segment was advanced by 10 mm. Cephalometric radiographs were taken at 6, 8, and 12 weeks postadvancement. At 12 weeks, the orthodontic appliance was removed, and at that time and 2, 4, and 6 weeks later, cephalometric radiographs were taken and study models fabricated. At the end of the postretention period, the animals were sacrificed, and the maxillae were evaluated by light microscopy. Results showed that the maxilla can be successfully advanced at a faster rate and for longer distances, and that the advanced maxilla does not relapse during the 6-week postretention period.

Animals↗

Early function of splinted implants in maxillas and posterior mandibles using Brånemark system machined-surface implants: an 18-month prospective clinical multicenter study.

BACKGROUND: There are limited clinical data available for immediately or early loaded implants placed in posterior mandibles and maxillas. This is probably because bone density often is low in these areas, making it difficult to establish good initial implant stability. By eliminating countersinking and using slightly tapered implants (Brånemark System , Mk IV, Nobel Biocare AB, Gothenburg, Sweden), however, high initial implant stability might be achieved in these regions. PURPOSE: The aim of this study was to investigate the possibility of early application of implant function in oral locations where the bone density is often low, namely the maxilla and posterior mandible. MATERIALS AND METHODS: Thirty-one patients were included consecutively in the study, and 36 edentulous areas in maxillas and posterior mandibles were treated. All patients were nonsmokers in good general health. Bruxism and uncontrolled periodontal disease were exclusion criteria. One hundred twenty-four machined-surface implants were placed using an insertion torque of at least 40 Ncm. Temporary prostheses with narrow occlusal platforms, flat cusps, and light occlusal contacts were generally placed within 1 week and not exceeding 20 days from implant placement. RESULTS: Of the 124 implants installed, 4 failed, 1 in each of four patients, giving an overall survival rate of 96.8% after 18 months. Two implants failed in maxillas and two in mandibles. One implant in a maxilla and one in a mandible were lost in an early stage, and the other two were lost a few months after placement. The prostheses' survival was 100%. CONCLUSIONS: This study shows that early implant function rehabilitation in maxillas and posterior mandibles is viable using the present clinical protocol. The results are comparable with those of conventional two-stage protocols.

Adult↗

Residual ridge resorption in the edentulous maxilla in patients with implant-supported mandibular overdentures: an 8-year retrospective study.

PURPOSE: This retrospective study radiologically investigated alveolar bone resorption in the edentulous maxilla in patients with implant-supported mandibular overdentures. MATERIALS AND METHODS: This study consisted of 35 healthy, completely edentulous patients with a mean age of 59.7 years. They had received two implants between the mental foramina. New bar-retained mandibular overdentures and maxillary complete dentures were fabricated. Standardized panoramic radiographs taken subsequent to loading and at annual recall visits for up to 8 years were measured for alveolar bone loss in the maxilla. Bone areas and areas of reference not subject to resorption were measured with a planimetry program. The proportional value between both was expressed as a ratio (R). Bone loss was expressed as a change in R between two time points. Differences in the resorption rate between the anterior and posterior parts of the maxilla were investigated. RESULTS: Residual ridge resorption continued during the follow-up period and revealed high individual variability. With a range of 5% to 11% (median) loss in the original bone height, it was significantly (P < .031) more pronounced in the anterior than posterior maxilla (2% to 7%) from the second through eighth years. Regression analysis of the medians revealed a relatively high correlation between time and bone loss in both anterior and posterior parts of the maxilla. CONCLUSION: The anterior anchorage of mandibular overdentures by means of two implants and an ovoid bar was associated with slightly higher resorption in the anterior than in the posterior part of the edentulous maxilla.

Alveolar Bone Loss↗

Clinical anatomy of the posterior maxilla pertaining to Le Fort I osteotomy in Thais.

This article studies the anatomy of the posterior maxilla pertaining to bone-cut design of Le Fort I osteotomy to avoid the injury to the descending palatine artery in Thais. Fifty-five skulls (38 males, 17 females) were assessed for the anatomical landmarks by a combination of direct inspection, computerized imaging, and computed tomography scan analysis. The results showed that 27.28% of the pterygomaxillary junction (PMJ) became synostosis. The mean heights of the PMJ, posterior maxilla, and maxillary tuberosity were 15.14 +/- 2.46 mm, 22.51 +/- 3.50 mm, and 7.45 +/- 2.76 mm, respectively. The mean length of the medial sinus wall measuring from the piriform rim to the descending palatine canal at the Le Fort I level was 34.40 +/- 2.96 mm. The mean widths of the posterior incision of Le Fort I osteotomy at the maxillary tuberosity and PMJ were 20.38 +/- 2.82 mm and 11.60 +/- 1.57 mm. The mean length of the posterior maxilla was 27.18 +/- 2.49 mm. Distances from the greater palatine foramen to the maxillary tuberosity incision and PMJ incision were 1.76 +/- 1.12 mm and 3.59 +/- 1.40 mm. The mean angle between the descending palatine canal and the hard palate was 57.33 +/- 4.54 degrees . There were no significant differences in any measurements between sides and genders, except the pterygoid process width and posterior maxilla length of males were longer than those of females (P < 0.05). This study could provide better understanding of the posterior maxillary anatomy that is important for the bone-cut design of Le Fort I osteotomy to avoid excessive intraoperative and postoperative hemorrhage including ischemia of the mobilized maxilla.

Female↗

[Follow-up studies of 3-dimensional osteoplastic reconstruction of the extremely atrophied maxilla combined with implants].

In the severely resorbed maxilla, a 10-year success rate of only 49-74% of implants in combination with autogenous bone grafts has been reported. We developed a modified technique of antral inlay grafting and lateral and vertical onlay grafting of the severely resorbed maxilla for inserting implants to retain dentures. The clinical and radiologic results are presented. In 21 patients with severely resorbed edentulous maxillae, a total of 20 bilateral and one unilateral antral inlay graftings and lateral and vertical onlay graftings were performed after a prosthodontic setup. We opened the maxillary sinus by removing a bony window from the anterolateral wall and, after elevation of the sinus lining, grafted the sinus floor with corticocancellous iliac crest bone grafts. The maxilla was also augmented in the lateral and vertical direction. The bone grafts were fixed by osteosynthesis. After a median of 5 months, a total of 134 implants (Brånemark) were placed and later loaded by prosthodontic rehabilitation. Computed tomography (CT) scans were taken before the grafting procedure, immediately after grafting, after 4 months, and every year thereafter. A total of 94.8% of the implants were successful at the time of the abutment operation. After loading, two additional failures were seen in an average follow-up period of 2.5 years. Most patients were provided with implant-borne dentures. CT scans showed an average initial gain of vertical bone height of 3.7-17.7 mm. One year after grafting, a loss of 1.3 mm or 7% occurred. In the following 2 years, no major atrophy was observed. Statistical analysis showed no correlation between sex, bone height before augmentation, augmented bone height, and resorption of the grafted bone. We observed undisturbed healing and obtained large vertical bone heights, a high success rate, minimal resorption, and fully satisfactory prosthodontic rehabilitation; we can thus recommend our modified technique of reconstruction of the severely resorbed maxilla for routine use.

Alveolar Bone Loss↗

Alterations in nasal airway resistance following superior repositioning of the maxilla.

Superior repositioning of the maxilla is a contemporary surgical procedure used to correct a variety of dentofacial deformities, including vertical maxillary excess. Concern for the effect of this procedure on nasal respiration is warranted, since superior repositioning of the maxilla may decrease the volume of the nasal cavity. In this study pre- and postoperative nasal-resistance values were obtained for 52 patients who underwent superior repositioning of the maxilla by the LeFort I downfracture procedure. Of these 52 patients, 24 underwent segmental osteotomies and 28 underwent one-piece superior repositioning. Results indicate that the long-faced persons for whom superior repositioning of the maxilla is recommended usually have pretreatment nasal-resistance values within previously reported normal ranges. Superior repositioning of the maxilla, with or without involvement of the nasal floor, usually results in decreased nasal resistance.

Adolescent↗

Simultaneous mobilization of the maxilla and mandible: surgical technique and results.

Simultaneous mobilization of the entire maxilla and mandible is a versatile procedure that can be used to correct multiple dentofacial deformities. The procedure is especially useful in correcting open bite deformities, as well as sagittal, vertical, and transverse dysplasias of the maxilla and mandible, and cases of asymmetry involving both the maxilla and mandible. Mock surgery performed on cephalometric tracings and study models provide a blueprint for the planned surgery. The use of an interim splint, constructed from sectioned models mounted on a semiadjustable articulator from a face bow transfer, is advocated to aid in accurate placement of the maxilla. The correct position of the maxilla is required to determine the ultimate position of the mandible; there is no room for error with this step if the procedure is to be accurate. Stabilization of the mobilized segments by direct osseous fixation, suspension wires, and maxillomandibular fixation is suggested. Maintenance of rigid maxillomandibular fixation for six weeks combined with an additional four weeks of guided mandibular function with skeletal elastics assures proper healing and position of segments.

Adult↗

Le Fort I sliding osteotomy--a procedure for stable inferior repositioning of the maxilla.

INTRODUCTION: Inferior repositioning of the maxilla for correction of vertical maxillary deficiency has been found to be associated with instability and a tendency to relapse. This can not be completely controlled by using bone grafts as relapse commences before complete integration of the graft. METHODS: Improved stability was sought by using rules of geometry when displacing the maxilla down a sloping plane. Anterior and inferior sliding of the maxilla after a double 'M'-shaped Le Fort I osteotomy was performed to preserve bony contact at the medial and lateral maxillary buttresses. The plan of this technique was derived from model surgery when true changes at the Le Fort I level were visualized. PATIENTS: 15 patients with class III-malocclusion and anterior vertical deficiency of the maxilla were surgically treated using this technique. RESULTS: Bony contact at the maxillary buttresses after anterior and inferior displacement was possible in patients with less than 6mm movement in a sagittal direction. Only minor skeletal relapse (mean: 0.4mm) was observed in the follow-up period (mean 14.2 months). CONCLUSION: The procedure should be considered whenever vertical maxilla relapse is of concern after anterocaudal displacement.

Adult↗