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1.
Using cone beam computed tomography (CBCT), the present study compared three-dimensional (3D) changes in the pharyngeal airway and surrounding tissues in female skeletal class III patients treated with bimaxillary surgery. Twenty-nine female skeletal class III patients with both maxillary hypoplasia and a mandibular excess underwent bilateral sagittal split ramus osteotomy for mandibular setback combined with Le Fort I osteotomy for maxillary advancement. Volumetric measurements were performed using CBCT scans taken at 1 week presurgery and 6 months post-surgery. The oropharynx volumes and the cross-sectional area behind the soft palate decreased significantly. There was an insignificant change in the volume of the nasopharynx (P > 0.05). The hyoid bone moved downward and posteriorly after surgery. The morphology of the soft palate also changed dramatically, with an increase in the length and thickness. Negative correlations were found between the pharyngeal airway space and the position of the hyoid bone. The change in morphology of the soft palate was significantly correlated with the changes in hyoid bone position. These 3D results suggest that bimaxillary orthognathic surgery significantly changes the position of the hyoid bone and the soft palate together with a significant decrease in the pharyngeal airway space in the correction of skeletal class III malocclusion.  相似文献   

2.
BackgroundThe purpose of this study was to evaluate nasal morphologic and maxillary skeletal changes occurring after bimaxillary surgery in skeletal class III patients, using a new method entailing superimposition of cone-beam computed tomography (CBCT) volumes.Materials & methodsThe subjects consisted of 30 adults (15 males and 15 females) who had presented with skeletal class III deformities. The subjects underwent Le Fort I advancement and impaction osteotomy and mandibular setback surgery. For closure of the maxillary vestibular incision, alar cinch suture and V-Y closure were performed. The pre- and post-operative CBCT data were superimposed and evaluated by voxel-by-voxel registration.ResultsAfter surgery, the nasolabial angle, nasal tip angle, nasal tip inclination and columellar angle showed significant increases (P < 0.01). The nasal tip protrusion and nasal height, meanwhile, had significantly decreased (P < 0.01), and the alar base width had increased (P < 0.01). The columellar length and nostril axis angle also had decreased, but the nostril area did not show any significant change.ConclusionsAfter surgery, as the maxilla had been moved upward and forward, the nasal tip was shifted antero-superiorly and the alar base width and nostrils were widened. CBCT superimposition, enabling 3D assessment of nasal morphologic changes, can be an effective tool for simultaneous measurement of skeletal and soft-tissue changes.  相似文献   

3.

Objective

The study aims to evaluate the pharyngeal airway space (PAS) following bimaxillary surgery in skeletal class III patients and to compare the changes in PAS between genders using cone-beam computed tomography (CBCT).

Materials and methods

In all, 38 patients (16 male and 22 female) with skeletal class III malocclusion underwent bimaxillary surgery. CBCT scans were acquired approximately 1 month before surgery, 3 months after surgery, and 6 months after surgery. The oropharyngeal volume and the minimum cross-sectional area (CSA) were characterized using the InVivoDental imaging software package at each time point.

Results

The volume and minimum CSA decreased significantly postoperatively, which was maintained until 6 months postoperatively (p < 0.01). The location of the minimum CSA tended to move into the retropalatal and retroglossal areas postoperatively. A strong correlation between volume and minimum CSA was found. The amount of mandibular setback was not correlated with the change in the airway. By gender, significant decreases in both the volume and minimum CSA were found in females (p < 0.05) but not in males.

Conclusion

Bimaxillary surgery significantly affects PAS. Gender differences should also be considered when considering changes in PAS.

Clinical relevance

An awareness of the effects of bimaxillary setback surgery on the airway should be considered when implementing an orthognathic treatment plan.
  相似文献   

4.
OBJECTIVE: To quantify the changes in the nose after bimaxillary surgery to correct skeletal Class III malocclusion and to test the hypothesis that there is no change in the nasal width following bimaxillary surgical correction of skeletal Class III when a nasal cinch is properly used. MATERIALS AND METHODS: Sixty-five adult Korean skeletal Class III patients who had received maxillary advancement/impaction and mandibular set-back surgery in conjunction with an alar base cinch suture were evaluated. The anthropometric variables of the nasal region were measured directly on the soft-tissue surface before and 6 months after surgery. RESULTS: After surgery, the alar width and alar base width had increased significantly (P < .001), while the nasal tip projection decreased (P < .001). The nostril morphology also showed widening (P < .001). There was a trend for females with a narrow alar width presurgically to have a larger amount of nasal widening compared with those with a broader alar width (P < .05). CONCLUSION: There is a high probability of nasal and nostril widening after bimaxillary surgery for skeletal Class III malocclusion in Koreans despite the careful performance of alar cinch suture. Nevertheless, the authors believe that alar cinch suture was positive in limiting the nasal widening to the minimum and would consider routine application during bimaxillary surgery for skeletal Class III especially for female patients with a narrow nose who are susceptible to these changes.  相似文献   

5.

Introduction

We present a retrospective study of 30 consecutive cases of bimaxillary orthognathic surgery with biodegradable self-reinforced poly-l/dL-lactide plates and tacks, for the same indication of Angle class III malocclusion. We reported the skeletal stability and morbidity at 1 year after surgery.

Patients and methods

All patients underwent bimaxillary procedure. We used self-reinforced poly-l/dL lactic acid copolymer. Stabilization of Lefort I osteotomy was achieved by four plates L-shaped. Sagittal split osteotomies were fixed by two straight-plates. Lateral cephalograms were taken before (T0), soon after (T1) and more than 1 year after surgery (T2). Eight standard landmarks and four angular measurements were taken into account. All differences of the landmarks and angles were measured at T1 and T2. The regular clinical follow-up was scheduled for a minimum period of 1 year.

Results

The mean advanced maxillary was 3.33 mm and the mean mandibular setback was 6.13 mm. The mean mandibular relapse was 2.2 mm (non-significant). Horizontal maxilla mean variation was 0.8 mm at 1 year at A-point. Vertical maxilla stability depends on maxillary movements: impaction stability is better as an isolated advancement or associated with pull-down movement. We found six inflammatory reactions and two of them need the removal of the plates.

Conclusion

Bimaxillary orthognathic procedure with bioresorbable osteosynthesis is a reliable and reproducible method. Angle class III malocclusions could be entirely and successfully managed with bioresorbable osteosynthesis. The stability and suites at 1 year are comparable to titanium osteosynthesis.  相似文献   

6.

Introduction

The purpose of this retrospective cephalometric study was to compare the stability of bilateral sagittal split osteotomy (BSSO) with extra-oral vertical ramus osteotomy (VRO) after correction of class III malocclusion by means of bimaxillary orthognathic surgery.

Methods

The sample comprised 51 consecutively treated patients, 38 females and 13 males, with a mean age of 19.1 years. All had a one-piece Le Fort I osteotomy with maxillary advancement and mandibular setback. VRO was performed in 30 cases, and BSSO was performed in 21 cases. Lateral cephalograms were obtained before surgery, within 1 week of surgery and 1 year after surgery.

Results

The mean forward movement of the maxilla was 5.6 mm in both groups (p < 0.001). The mean horizontal surgical change in the VRO group was 4.4 mm (p < 0.001), and in the BSSO group it was 5.4 mm (p < 0.001). In the VRO group, the horizontal relapse was 1.2 mm (p < 0.001), and in the BSSO group, it was 1.4 mm (p < 0.001).

Conclusion

There was no difference in the stability between the BSSO and VRO groups. The average relapse in the whole sample was 26% of the surgical movement.  相似文献   

7.

Introduction

Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient’s life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions.

Materials and methods

This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery.

Conclusion

The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only.  相似文献   

8.
Objective:To evaluate the pharyngeal airway and maxillary sinus volume changes after mandibular setback surgery combined with maxillary advancement and/or impaction surgery.Materials and Methods:Seventeen Class III skeletal patients (11 females, 6 males) who required bimaxillary orthognathic surgery were selected. Volumetric measurements were performed using cone beam computed tomography (CBCT) scans preoperatively and 3.9 ± 0.87 months postoperatively. All the CBCT scans were assessed and analyzed using MIMICS 14.0 software. Preoperative and postoperative volumes of pharyngeal airway and maxillary sinuses and the relationship between the amounts of surgical movement of the jaws and the above volumes were statistically evaluated.Results:The pharyngeal airway area presented no significant change except for the lower and total pharyngeal airway volumes in males, in whom a significant decrease was observed (4196.27 ± 2061.11 mm3 and 3375.53 ± 3624.67 mm3, respectively). No significant change was observed in the minimal cross-sectional area of the pharyngeal airway. There was a significant decrease in the volume of the maxillary sinuses after the surgery by 3448.09 ± 3315.56 mm3. No correlation was found between the amount of skeletal movement and the change in the volume of pharyngeal airway or maxillary sinuses.Conclusion:There was a significant decrease only for lower and total pharyngeal airway volumes in males and a significant decrease in the volume of the maxillary sinuses.  相似文献   

9.
PURPOSE: The aim of this study was to evaluate skeletal stability after double jaw surgery for correction of skeletal Class III malocclusion to assess if there were any differences between resorbable plate and screws and titanium rigid fixation of the maxilla. PATIENTS AND METHODS: Twenty-two Class III patients had bilateral sagittal split osteotomy for mandibular setback stabilized with rigid internal fixation. Low level Le Fort I osteotomy for maxillary advancement was stabilized with conventional titanium plate and screws in 12 patients (group 1) and with resorbable plate and screws in 10 patients (group 2). Lateral cephalograms were taken before surgery, immediately postoperatively, 8 weeks after surgery, and 1 year postoperatively. RESULTS: Before surgery both groups were balanced with respect to linear and angular measurements of craniofacial morphology. One year after surgery, maxillary stability was excellent in both groups. In group 1 no significant correlations were found between maxillary advancement and relapse. In group 2, significant correlations were found between maxillary advancement and relapse at A point and posterior nasal spine. No significant differences in postoperative skeletal and dental stability between groups were observed. CONCLUSION: Surgical correction of Class III malocclusion after combined maxillary and mandibular procedures appears to be a fairly stable procedure for maxillary advancements up to 5 mm independently from the type of fixation used to stabilize the maxilla. Resorbable devices should be used with caution for bony movements of greater magnitude until their usefulness is evaluated in studies with large maxillary advancements.  相似文献   

10.
The impact of orthognathic surgery for class III malocclusion on ventilation during sleep was examined using a comparison of pre- and post-surgical respiratory parameters. 21 patients with both maxillary hypoplasia and mandibular excess underwent Le Fort I osteotomy and advancement together with bilateral sagittal split osteotomy (BSSO) setback. Respiratory parameters, ECG and position of the body were monitored before surgery and postoperatively after the fixation removal (mean 8.5 months). Average Le Fort I advancement was 4.44 mm, BSSO setback was 4.96 mm. Generally, the orthognathic procedure worsened breathing function during sleep, as reflected in significant increase of index of flow limitations and decrease in oxygen saturation. The posterior airways space decreased to 75% of its original volume, the distance between mandibular plane and hyoid bone increased to 133%. The results indicate that bimaxillary surgery for class III malocclusion increased upper airway resistance. A young person would probably be able to balance such a decline in respiratory function using different adaptive mechanisms, but the potential impact of orthognathic surgery on the upper airways should be incorporated in a treatment plan.  相似文献   

11.
The purpose of this study was to evaluate the volumetric change of the upper airway space in 36 Class III patients who had undergone bimaxillary surgery or isolated mandibular setback, and, further, to analyse the relation between post-surgical stability and airway change using cone-beam computed tomography (CBCT). A three-dimensional (3D) CBCT examination was performed at three stages: T0 (before surgery), T1 (an average of 4.6 months after surgery), and T2 (an average of 1.4 years after surgery). The results showed that the volumes of the oropharyngeal and hypopharyngeal airways decreased significantly 4.6 months post-surgery in the mandibular setback group (p<0.05), and these diminished airways had not recovered 1.4 years post-surgery. In the bimaxillary surgery group, the volume of the oropharyngeal airway also decreased. A Spearman correlation analysis showed that the anteroposterior length of the hypopharyngeal area had a correlation with post-surgical stability in the isolated mandibular surgery group, and that the cross-sectional area of the nasopharynx was correlated with maxillary relapse only in the bimaxillary surgery group (p<0.05).  相似文献   

12.
The maxilla-first approach has been the standard orthognathic sequence for many years, however, with the evolution of rigid internal fixation and to eliminate any errors that could be encountered during preoperative bite registration, the mandible-first approach has become an effective treatment modality for bimaxillary orthognathic surgery. Would the maxilla-first or mandible-first orthognathic sequence in bimaxillary orthognathic surgery result in more maxillary stability in patients with skeletal class III malocclusion? Twenty-four patients with skeletal class III malocclusion were selected from the outpatient clinic of the Oral and Maxillofacial Surgery Department, Faculty of Dentistry, Cairo University. Patients were randomly divided into two equal-sized groups: the maxilla-first approach (group I), and the mandible-first approach (group II). All patients underwent cone-beam computed tomography before, immediately after (P1), and 6 months after surgery (P2). Virtual planning included designing the virtual cuts and the intermediate and final splints. Both splints were three-dimensionally printed. In both approaches, hard and soft tissue landmarks were used as reference points to evaluate maxillary stability, which was calculated by subtracting P2 values from P1 values. All measures were statistically evaluated as numerical values of means and standard deviations. The differences between the radiographic measurements of the two groups were not statistically significant except for the soft tissue inclination at the nasal tip. The mandible-first approach in bimaxillary orthognathic surgery is a reliable method for achieving high maxillary stability.  相似文献   

13.
A stable occlusion at the time of surgery is considered important for post-surgical stability after orthognathic surgery. The aim of this study was to determine whether skeletal stability after bimaxillary surgery using a surgery-first approach for skeletal class III deformity is related to the surgical occlusal contact or surgical change. Forty-two adult patients with a skeletal class III deformity corrected by Le Fort I osteotomy and bilateral sagittal split osteotomy with a surgery-first approach were studied. Dental models were set and used to measure the surgical occlusal contact, including contact distribution, contact number, and contact area. Cone beam computed tomography was used to measure the surgical change (amount and rotation) and post-surgical skeletal stability. The relationship between skeletal stability and surgical occlusal contact or surgical change was evaluated. No relationship was found between maxillary or mandibular stability and surgical occlusal contact. However, a significant relationship was found between maxillary and mandibular stability and the amount and rotation of surgical change. The results suggest that in the surgical-orthodontic correction of skeletal class III deformity with a surgery-first approach, the post-surgical skeletal stability is not related to the surgical occlusal contact but is related to the surgical change.  相似文献   

14.

Objectives

The aim of this work was to evaluate the skeletal modifications obtained on transverse plane in adult patients, subjected to maxillary segmented Le Fort I osteotomy and sagittal mandibular osteotomy by Epker in the same surgical procedure, and to consider if the improvement provided to transverse diameters of the face was real and statistically significant.

Materials and methods

20 patients of both genders (8 females and 12 males) aged 22 to 47 years and showing a transverse maxillary hypoplasia, associated to alterations on sagittal and vertical plane, were analysed. A posteroanterior teleradiography before, after treatment and during a 6 months follow-up was prescribed to each patient. On these radiographs, cephalometric evaluations were performed, according to the Milan School guidelines.

Results

After treatment, the transverse dimensions of the maxilla and nasal cavity, the width of the upper and lower dental arch increased in all patients considered. Furthermore, the correction of the original dysmetrias and the recovery of dentofacial and skeletal symmetry were observed.

Conclusions

Through segmented Le Fort I osteotomy, combined with mandibular osteotomy, it was possible to obtain a real and statistically significant improvement in the transverse diameter of the face, with the great advantage of solving both the maxillary and mandibular malocclusion in a single-phase surgery.  相似文献   

15.
目的:通过锥形束CT(cone beam computer tomography,CBCT)观察骨性Ⅲ类错患者双颌手术后鼻咽及口咽部气道及其周围软硬组织的变化。方法:纳入双颌手术治疗的骨性Ⅲ类错患者19例,女性12名,男性7名,平均年龄23.8岁。分别于术前1周及术后3个月拍摄CBCT扫描照片,通过Mimics 10.01建立术前及术后鼻咽、口咽气道三维影像并进行测量。结果:术后患者口咽部容积与气道总容积(包括鼻咽与口咽)均显著减小(P<0.05),口咽部气道容积平均减小8.37%,气道总容积平均减小6.91%。术后软腭处气道横截面积平均减小19.83%(P<0.05)。舌骨位置、软腭形态均有明显变化(P<0.05)。术后气道分别与舌骨位置(H-X,H-Y)、软腭形态变化(PNS-UT,U-T,UT/ANS)有显著相关性(P<0.05),软腭形态变化与舌骨位置变化也具有显著相关性(P<0.05)。结论:骨性Ⅲ类错患者双颌术后气道容积减小。  相似文献   

16.
Many reports have paid attention to skeletal stability after orthognathic surgery, but only few focalize attention on patients with III class III malocclusion and open bite. In this article, long-term stability (2 yr) of the maxilla and the mandible after orthognathic surgery in 40 patients with class III malocclusion and anterior open bite is evaluated. The sample has been obtained from those 420 patients with class III malocclusion treated with Le Fort I osteotomy isolated (group A, 20 patients) or in association with bilateral sagittal split osteotomy (group B, 20 patients) from 1985 to 2003. On the basis of cephalometric analysis obtained in the immediate postoperative period and 2 years after surgery, in class III patients with anterior open bite treated with mono- or bimaxillary surgery and stabilization with rigid internal fixation, the maxilla was demonstrated to remain in the postsurgical position, whereas a moderate rate of mandibular relapse dependent on the amount of surgical alteration of the mandibular position was present.  相似文献   

17.
This study employed the cone-beam computed tomography (CBCT) superimposition method to evaluate postoperative midfacial soft-tissue changes in cases of skeletal Class III malocclusion after double-jaw surgery with setback and vertical reduction Le Fort I osteotomy. A retrospective study was carried out on 15 patients who had undergone maxillary setback Le Fort I osteotomy and mandibular setback sagittal split ramus osteotomy with alar cinch suturing and V-Y soft-tissue closure. Three dimensional CBCT volume scans were recorded preoperatively (T0) and 6 months postoperatively (T1) to measure soft-tissue changes of the upper lip and midface. Post-surgery, soft-tissue landmarks in the cheek and paranasal areas had moved forward; the soft-tissue thickness at the A-point had markedly increased (P < 0.05); there was no significant change in the subnasale, and the midline of the soft-tissue of the upper-lip area had moved backward. The extent of the mean soft-tissue change at the labrale superius was greater than that at the other soft-tissue landmarks of the upper lip. The results suggest that maxillary setback movement of the maxilla by alar cinch suturing has a beneficial effect on paranasal soft-tissue and lip contours for patients with protrusive lip and acute nasolabial angle.  相似文献   

18.
A total of 40 patients with varying degrees of facial skeletal deformity and Class III malocclusion were treated by bimaxillary osteotomy combining maxillo-malar augmentation and/or osseous genioplasty at the same sitting by the author. In all patients, the maxillary advancement and mandibular set back were performed, using Le Fort I maxillary osteotomy and bilateral sagittal split osteotomy of the mandibular rami. In additional bimaxillary osteotomy, simultaneous maxillo-malar augmentation and genioplasty in 20 patients, genioplasty in 12 patients, maxillo-malar augmentation in eight patients, were performed to improve facial harmony. All patients were followed clinically and radiographically for at least 1 year and as much as 5 years after undergoing surgical correction. No cases with relapse or other major complications have been encountered up to now. There were, however, persisting unilateral inferior alveolar nerve damage in two patients, prolonged nerve anesthesia or hypoesthesia in four patients, and short period anesthesia or hypoesthesia in 11 patients, wide alar base in three patients and slight deviation of cartilage septum in two patients. There were no other complications encountered and an unexpected result. The facial skeletal deformity and malocclusion were always treated satisfactorily as patient and plastic surgeon's expectations in one-stage operation, without significant complications and morbidity.  相似文献   

19.

Objectives

The present study investigated the position and relationship of the maxillary third molars to the maxillary sinus. These molars were detected to have a close relationship with the maxillary sinus based on panoramic images, using cone-beam computed tomography (CBCT).

Methods

This retrospective study evaluated 162 impacted third molars from 100 patients that showed a superimposed relationship between the maxillary sinus and third molars on panoramic images obtained from CBCT. CBCT images were used to assess the horizontal (buccopalatal) and vertical positions of the maxillary sinus relative to the maxillary third molars, proximity of the roots to the sinus, and angulation and depth of the third molars. The associations among the angulation, depth of third molars, and horizontal and vertical positions of the maxillary sinus relative to the third molar findings were examined using Chi square tests.

Results

Based on the winter classification, the most frequent tooth position was vertical (59.9 %), followed by mesioangular (14.2 %), distoangular (9.9 %), and others. Most impacted teeth were at the level between the occlusal and cervical levels of the adjacent second molar. Regarding the relationships of the maxillary third molars with the maxillary sinus examined on CBCT, vertical type III (buccal root related with maxillary sinus) (34 %) and horizontal type 2 (maxillary sinus located between roots) (64.8 %) were seen most frequently.

Conclusions

The relationship between the maxillary sinus and third molar roots should be considered during extraction. When a risk of sinus perforation is predicted in an extraction, a presurgical CBCT examination could be valuable.
  相似文献   

20.
We previously reported a modified technique for the placement of symmetrical cinch sutures after switching from a nasal to an oral endotracheal tube. We undertook a study to assess the effectiveness of our technique and the stability of changes in the nasolabial morphology after bimaxillary surgery. The study group comprised 30 patients aged 17-36 years who had skeletal Class III malocclusion. All patients had bimaxillary surgery with an alar base cinch suture and V-Y closure. The nasal region was measured directly or on cephalograms before, and 1 week and 1 year after operation. The suture did not alter the width of the alar base, but the nasolabial angle and projection of the tip increased significantly. The length of the upper lip did not change significantly.  相似文献   

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