Changes in acoustic airway profiles and nasal airway resistance after Le Fort I osteotomy and functional rhinosurgery: a prospective study

Morphological changes in the inferior nasal passage associated with superior repositioning of the maxilla with/without horseshoe osteotomy or turbinectomy

Superior repositioning of the maxilla during Le Fort I osteotomy (LFI) may narrow the inferior nasal passage. This retrospective study was performed to investigate morphological changes in the inferior nasal passage following LFI with/without additional procedures performed for nasal ventilation (horseshoe osteotomy or inferior turbinate partial resection). Three groups of patients were compared: those undergoing conventional LFI (Conv, 63 patients), LFI with horseshoe osteotomy (Hs, eight patients), and LFI with inferior turbinate partial resection (Turb, 21 patients). Coronal computed tomography images were used to evaluate the degree of stenosis of the inferior nasal passage. The soft tissue and bony tissue volumes in the inferior turbinate were also calculated three-dimensionally. The rate of obstruction of the inferior nasal passage postoperative was 65.9%, 50%, and 11.9% in the Conv, Hs, and Turb groups, respectively (Fisher's exact test, P < 0.001). Patients in the Turb group had significantly less nasal obstruction regardless of the pitch direction of the maxillary movement or volume of the bone in the inferior turbinate (all P < 0.001). In conclusion, for patients with high superior repositioning and well-developed bony tissue in the inferior turbinate, additional procedures are recommended to maintain the ventilation of the nasal passage postoperatively.

The Effects of the Maxillary Movements in Angle Class 2 and 3 Malocclusion Treatment on Nose Air Flow Amount, Rate, and Resistance

Maxillary movements performed during orthognathic surgery affect the external and internal anatomy of the nose. The functional and anatomical effects may change nasal airway parameters after the surgery, and these alterations can be examined objectively by rhinomanometry. In this study, patients who underwent maxillary orthognathic surgery were divided into 3 groups based on their surgical plans: advancement (group 1), impaction and advancement (group 2), and setdown and advancement (group 3). Preoperative and postoperative rhinomanometric data including the average nasal volume, minimum cross-sectional area, average airflow resistance of the right and left nasal passageways, and an average of both nasal passages were collected. The study included 50 patients who underwent orthognathic surgery between October 2021 and October 2022. There were 20 patients each in group 1 and group 2 and 10 patients in group 3. The average nasal passage volume increased in the advancement (group 1) and impaction-advancement (group 2) groups. In addition, the advancement (group 1) group had a decreased average airflow resistance. Setdown-advancement (group 3) group did not show a positive or negative effect on nasal airway parameters. Maxillary movements during orthognathic surgery revealed no adverse effect on nasal parameters. Moreover, advancement and impaction positively affected nasal functional and anatomical parameters.

Assessment of Nasal Septum Change after Le Fort I Osteotomy Using Cone Beam Computed Tomography

Objective

Le Fort I osteotomy (LF-IO) is widely used for the correction of dentofacial deformities, which may cause changes in the postoperative nasal septum (NS). The objective of this study was to evaluate the effects of LF-IO on the NS deviation and to determine whether the NS was affected by differences in the direction of maxilla movement.

Materials and Methods

A retrospective study including 57 patients who underwent LF-IO and received cone beam computed tomography (CBCT) preoperatively and 6-12 months postoperative evaluation was performed. The NS angle of each patient was measured both pre- and postoperatively in the two coronal sections (nasion and ostium levels). The patients were divided into five paired groups and calculated. Group 1 to 4 were divided depending on the differences in the direction of maxilla movement (Group 1. Impaction ≥ 5 mm vs. Impaction < 5 mm; Group 2. Anterior movement vs. Non-anterior movement; Group 3. Impaction symmetry vs. Impaction asymmetry; and Group 4. Impaction vs. Inferior repositioning). Group 5 was divided as One-piece osteotomy vs. Multi-segmental osteotomy.

Results

The mean NS angles at both nasion and ostium levels of all patients were significant increased after LF-IO. However, there were no statistical significant differences of the five paired groups.

Conclusions

LF-IO osteotomy influenced increasing of the NS deviation at both the nasion and ostium levels. However, differences in the direction of the maxilla movement and maxilla segmentation showed no statistically significant changes.

Study of Anatomical Changes of the Inferior Nasal Passage After Le Fort I Osteotomy With Superior Repositioning

The relationship between postoperative morphological changes in the inferior nasal cavity and inferior turbinate after Le Fort I osteotomy remains unclear. This study aimed to investigate how the bone volume of the inferior turbinate affects contact with the inferior nasal cavity of patients who underwent superior repositioning. We evaluated the 3-dimensional relationship between the anatomical changes in the inferior nasal passage before and after surgery in 51 patients who underwent Le Fort I osteotomy with an elevation of >4.0 mm in the first molar. The soft tissue and bone volumes of the inferior turbinate and airway volume of the inferior nasal passage were calculated using Proplan CMF 3.0 and compared according to the size of the bone volume of the inferior turbinate. In addition, we reclassified the maxillary movements in the pitch direction and compared the results. The contact rates of the postoperative inferior nasal airway and the inferior turbinate in the large-bone group was 72.3% and that in the small-bone group was 40.0% in the χ2 test. The reduction in the inferior nasal passage volume was significantly greater in the large-bone group (pitch+) than in the small-bone group (pitch+). For patients with well-developed bony tissue of the inferior turbinate, caution is advised if the maxillary elevation is ≥4.0 mm, because the possibility of postoperative obstruction of the inferior nasal passages exist, which may lead to deterioration of nasal ventilation.

Long-term vertical stability of horseshoe osteotomy for the correction of large vertical excess of the maxilla, a retrospective assessment in 15 patients

INTRODUCTION

Vertical stability after a Le Fort I (LF1) osteotomy with substantial upward movement can be compromised by the position and the volume of the inferior turbinate. A horseshoe (HS) osteotomy represents then an alternative as it preserves the hard palate and the intranasal volume. The aim of this study was to assess the vertical stability of the maxilla after HS osteotomy.

MATERIALS AND METHODS

Patients who underwent a HS osteotomy for the correction of long-face syndrome were retrospectively analyzed. The vertical stability was assessed on lateral cephalograms performed preoperatively (T0), immediately postoperatively (T1), and at the last follow-up (T2) by studying points C (the distal cusp of the first maxillary molar), point P (the prosthion, the lowest edge of the maxillary alveolus of the central incisor), and point I (the upper central incisor edge) in a coordinate system. Postoperative complications and aesthetics of the smile were also investigated.

RESULTS

Fifteen patients were included (7 females, 8 males, mean age 25.5 ± 9.8 yeras). The mean impaction ranged from 5 mm on point P to 6.1 mm on point C, with a maximal movement of 9.5 mm. A non-significant relapse of 0.8 ± 1.7, 0.6 ± 0.8, and 0.5 ± 1.8 mm was observed after a mean 20.7 months on point C, P, and I respectively. Smile parameters were significantly improved by the procedure, mainly regarding the correction of the gum smile.

CONCLUSION

HS osteotomy represents a good alternative to total LF1 osteotomy for substantial maxillary upward movement in long face syndrome deformities.

Efficacy of Nostril Supportive Splint Treatment for Nasal Septum Deformities after Le Fort I Osteotomy

This retrospective study aimed to evaluate the efficacy of support splint treatment for deformities and deviations of the nasal septum after Le Fort I osteotomy (LFI). Patients were divided into two groups: the retainer group wore a nasal support splint immediately after LFI for 7 days, and the no retainer group did not wear a nasal support splint. Evaluation was performed by measuring the ratio of the difference between the left and right sides of the nasal cavity area (ratio of nasal cavity) and the angle of the nasal septum using three computed tomography frontal images (anterior, middle, and posterior) before and one year postoperatively. Sixty patients were included and divided into two groups, the retainer and no retainer group (n=30 each). Regarding the ratio of nasal cavity on middle images at one year postoperatively, the retainer and no retainer groups differed significantly (0.79±0.13 and 0.67±0.24, respectively; P =0.012). The angle of the nasal septum on anterior images at one year postoperatively was 164.8±11.7° in the retainer group and 156.9±13.5° in the no retainer group, showing a significant difference ( P =0.019). This study suggests that support splint treatment after LFI is effective in preventing post-LFI nasal septal deformation or deviation.

Nasal Airway Function After Prophylactic Intranasal Surgery for Excessive Maxillary Superior Repositioning: A Retrospective Cohort Study Using the Nasal Obstruction Symptom Evaluation Scale

PURPOSE

The purpose of this study is to evaluate the degree of nasal airway function after simultaneous intranasal corrective surgery and bimaxillary surgery in patients with excessive superior maxillary repositioning.

MATERIALS AND METHODS

A retrospective cohort study was conducted on consecutive LeFort I superior repositioning patients who also underwent simultaneous intranasal surgery to prevent airway obstruction between 2015 and 2019. The Nasal Obstruction Symptom Evaluation (NOSE) scale was administered to all participants before the operation and after 1 year.

RESULTS

Fifteen patients (n=12 females; n=3 males) among 440 bimaxillary orthognathic surgery patients were enrolled with inclusion criteria of maxillary impaction between 8 and 12 mm. All subjects underwent at least LeFort I osteotomy, septoplasty, bilateral inferior turbinectomy, and bilateral sagittal split osteotomy. Two patients received custom-made total joint prosthesis. The primary outcome variable investigated was nasal function. The mean preop Nasal Obstruction Symptom Evaluation score was 24.33 and the mean postop score was 5.

CONCLUSIONS

Intranasal procedures performed simultaneously with 8 mm or more maxillary impaction improves postoperative functional outcome in terms of nasal airway patency and breathing. Partial inferior turbinectomies and septoplasty should be performed consistently to avoid nasal obstruction if the impaction of upper jaw exceeds 8 mm.

What Is the Effect of Maxillary Impaction Orthognathic Surgery on Voice Characteristics? A Quasi-Experimental Study

Background

Regarding the impact of orthognathic surgery on the airway and voice, this study was carried out to investigate the effects of maxillary impaction surgery on patients' voices through acoustic analysis and articulation assessment.

Methods

This quasi-experimental, before-and-after, double-blind study aimed at examining the effects of maxillary impaction surgery on the voice of orthognathic surgery patients. Before the surgery, a speech therapist conducted acoustic analysis, which included fundament frequency (F0), Jitter, Shimmer, and the harmonic-to-noise ratio (HNR), as well as first, second, and third formants (F1, F2, and F3). The patient's age, sex, degree of maxillary deformity, and impaction were documented in a checklist. Voice analysis was repeated during follow-up appointments at one and six months after the surgery in a blinded manner. The data were statistically analyzed using SPSS 23, and the significance level was set at 0.05.

Results

Twenty two patients (18 females, 4 males) were examined, with ages ranging from 18 to 40 years and an average age of 25.54 years. F2, F3, HNR, and Shimmer demonstrated a significant increase over the investigation period compared to the initial phase of the study (P <0.001 for each). Conversely, the Jitter variable exhibited a significant decrease during the follow-up assessments in comparison to the initial phase of the study (P< 0.001).

Conclusion

Following maxillary impaction surgery, improvements in voice quality were observed compared to the preoperative condition. However, further studies with larger samples are needed to confirm the relevancy.

Study of Morphological Changes in the Inferior Turbinate After Le Fort I Osteotomy

OBJECTIVE

There are cases in which patients complain of nasal obstruction after Le Fort I osteotomy, but the relationship with postoperative morphological changes in the nasal cavity, including the septum and inferior turbinate, is not clear.

STUDY DESIGN

The authors evaluated the three-dimensional relationship of the morphological changes in the inferior turbinate before and after surgery in 84 patients who underwent Le Fort I osteotomy. Three classifications were made according to superior amount of maxillary movement at the base of nasal cavity.

RESULTS

The high elevation group (4.0 mm or more) had 31 sides, the moderate elevation group had 93 sides, and the low elevation group (less than 2.0 mm) had 44 sides. The volume of inferior turbinate was 76.9 ± 12.8% of that before surgery in the high elevation group. The high- and moderate-elevation groups had significantly higher changes than the low elevation group, and the rate of contact between inferior turbinate and nasal cavity floor was 67.7%.

CONCLUSIONS

After Le Fort I osteotomy, the volume of inferior turbinate tissue decreased in proportion to the amount of elevation of the maxilla. Although the soft tissue volume may be reduced due to adaptation of respiratory function, the inferior nasal passage was not completely ventilated in the high elevation group. If the elevation exceeds 4.0 mm counterclockwise with maxillary movement, it is necessary to consider the concomitant inferior turbinate resection because it may lead to nasal obstruction.

Computed Tomography Assessment of Maxillary Sinus and Inferior Nasal Airway After Le Fort I Osteotomy

PURPOSE

This study aimed to evaluate and predict the factors that affect the postoperative maxillary sinus and inferior nasal cavity conditions after Le Fort I osteotomy.

SUBJECTS AND METHODS

The rate of aerated (healthy) sinus area and the inferior nasal airway area were calculated by preoperative computed tomography measurements and at 1 week and 1 year postoperatively. Factors predicting the rate of aerated sinus area and the ratio of the inferior nasal cavity area after 1-week were examined using these variables.

RESULTS

The subjects consisted of 112 patients (224 sides) who underwent Le Fort I osteotomy with sagittal split ramus osteotomy. The rate of aerated sinus area after 1 week was significantly correlated with sex, age, and amount of blood loss (P < 0.0001). The rate of the inferior nasal cavity area after 1 week was significantly correlated with the anterior impaction amount of the maxilla and the preoperative rate of the inferior nasal airway area (P= 0.0017).

CONCLUSIONS

This study suggests that attention should be paid to females, older patients, and the amount of blood loss to prevent sinusitis, and larger maxillary impaction at the anterior site should be carefully planned to prevent severe nasal obstruction immediately after Le Fort I osteotomy.

Computational fluid dynamic analysis of the nasal respiratory function before and after postero-superior repositioning of the maxilla

Morphological changes in the upper airway and the resulting alteration in the nasal respiratory function after jawbone repositioning during orthognathic surgery have garnered attention recently. In particular, nasopharyngeal stenosis, because of the complex influence of both jaws, the effects of which have not yet been clarified owing to postero-superior repositioning of the maxilla, may significantly impact sleep and respiratory function, necessitating further functional evaluation. This study aimed to perform a functional evaluation of the effects of surgery involving maxillary repositioning, which may result in a larger airway resistance if the stenosis worsens the respiratory function, using CFD for treatment planning. A model was developed from CT images obtained preoperatively (PRE) and postoperatively (POST) in females (n = 3) who underwent maxillary postero-superior repositioning using Mimics and ICEM CFD. Simultaneously, a model of stenosis (STENOSIS) was developed by adjusting the severity of stenosis around the PNS to simulate greater repositioning than that in the POST. Inhalation at rest and atmospheric pressure were simulated in each model using Fluent, whereas pressure drop (ΔP) was evaluated using CFD Post. In this study, ΔP was proportional to airway resistance because the flow rate was constant. Therefore, the magnitude of ΔP was evaluated as the level of airway resistance. The ΔP in the airway was lower in the POST compared to the PRE, indicating that the analysis of the effects of repositioning on nasal ventilation showed that current surgery is appropriate with respect to functionality, as it does not compromise respiratory function. The rate of change in the cross-sectional area of the mass extending pharynx (α) was calculated as the ratio of each neighboring section. The closer the α-value is to 1, the smaller the ΔP, so ideally the airway should be constant. This study identified airway shapes that are favorable from the perspective of fluid dynamics.

Effect of maxillary surgical movement on nasal cavity and maxillary sinus dimensions and function after Le Fort I osteotomy

This study was designed to evaluate the effects of different maxillary movements performed in Le Fort I surgery on the anatomy of the nasal cavity and maxillary sinus, occurrence of rhinosinusitis, and nasal airflow. Patients were divided into three groups: group I underwent pure advancement, group II underwent advancement with yaw rotation, and group III underwent advancement with impaction movements. All evaluations were performed using pre- and postoperative computed tomography images and surveys. Twenty-eight patients were enrolled. The mean pre- and postoperative nasal air volumes in group I were 22.74 ± 6.32 cm³ and 25.17 ± 6.19 cm³, respectively, showing a significant increase (P = 0.041). The mean pre- and postoperative maxillary sinus air volumes were 33.94 ± 13.72 cm³ and 26.28 ± 14.12 cm³ in group II and 35.29 ± 9.58 cm³ and 28.65 ± 8.42 cm³ in group III, respectively, showing significant reductions (P = 0.028 and P = 0.007, respectively). For all movements, the occurrence of septum deviation and nasal airflow impairment was not statistically significant. Pure maxillary advancement movement enhanced nasal cavity air volume. The yaw rotation movement significantly increased quantitative clinical rhinosinusitis symptoms. The risk of airflow impairment following Le Fort I surgery is low.

Evaluation of Nasal Function and Upper Airway Morphology After Bi-Maxillary Surgery Using Rhinomanometry and Computed Tomography

PURPOSE

This study was performed to evaluate changes in nasal airflow, nasal airway resistance, nasal cross-sectional area, pharyngeal horizontal area, nasopharyngeal and oropharyngeal volume following Le Fort I osteotomy (L1) impaction with sagittal split ramus osteotomy (SSRO) in classes II and III.

MATERIALS AND METHODS

The subjects consisted of 35 patients (6 males and 29 females, 70 sides) 17 of which were diagnosed as class II and 18 as class III who underwent L1 and SSRO. Nasal airflow and resistance were measured using the rhinomanometry system (GM NR-6 EXECUTIVE) before and at 1 and 6 months after surgery. Nasal, cross-sectional area, and volume were measured using a 3-dimensional computed tomography respectively, before and 1-year after surgery.

RESULTS

Although a significant decrease was found in nasal volume after surgery (P = 0.0042), there was no difference between before and after surgery in the nasal airway resistance in class II.A significant decrease in nasal volume was found after surgery (P = 0.0005) and there were no postoperative changes in both nasal airflow and resistance in class III.

CONCLUSION

The study suggested that L1 impaction with SSRO did not worsen nasal function such as nasal airflow and nasal airway resistance, although nasal volume significantly decreased in both groups.

Functional and Radiological Assessment After Preservation Rhinoplasty - A Clinical Study

BACKGROUND/AIM

We hypothesized that improved functional outcome after preservation rhinoplasty can be validated by radiological analyses.

PATIENTS AND METHODS

In this retrospective study, five patients were included. Radiological assessment was evaluated by cone-beam computed tomography. Patient satisfaction regarding nasal function was evaluated by a Likert scale from 0 to 10 (0=poor result; 10=very satisfied).

RESULTS

After a mean follow-up of 5±1 months (range=4-6 months), significantly improved function was noted by all patients, with a mean Likert scale of 9.2±0.45 (preoperative score=2.8±0.8, p=0.0079). These results are in line with the radiological results, showing an improved internal nasal valve angle (preoperative=26.2°±1.8° vs. postoperative=32.3°±1.2°, p=0.02).

CONCLUSION

Our study showed that besides nasal appearance, nasal function can also be dramatically improved after preservation rhinoplasty.

The Impact of Maxillary Expansion on Adults' Nasal Breathing: A Systematic Review and Meta-Analysis

OBJECTIVE

Nasal surgery fails to restore nasal breathing in some cases. Maxillary constriction is suggested as a major cause of failure. It is thought that maxillary constriction leads to the closure of the internal and external nasal valves. Moreover, it is well established in the literature that maxillary expansion, both in adults and children, increases upper airway volume. However, it is yet unclear whether maxillary expansion may improve nasal function.Review Methods: Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked by two authors from the Rhinology Study Group of the Young Otolaryngologists section of the International Federation of Otorhinolaryngological Societies. Two authors extracted the data. The main outcome was expressed as the value (in variable units) prior to treatment (T0), after expansion procedures (T1), after the retention period (T2), and after a follow-up period (T3).

RESULTS

A total of 10 studies (257 patients) met the inclusion criteria. The data pooled in the meta-analysis reveals a statistically significant reduction of 0.27 Pa/cm³/s (CI 95% 0.15, 0.39) in nasal resistance after palatal expansion As far as subjective changes are concerned, the pooled data for the change in the NOSE score shows a statistically significant mean reduction after maxillary expansion of 40.08 points (CI 95% 36.28, 43.89).

CONCLUSION

The initial available evidence is too limited to suggest maxillary expansion as a primary treatment option to target nasal breathing. However the data is encouraging with regards to the effect of maxillary expansion on nasal function. Further higher quality studies are needed in order to define clearer patient selection criteria, distinguish optimal techniques, and demonstrate long-term efficacy in long term follow up studies.

Nasal airway function after Le Fort I osteotomy with maxillary impaction: A prospective study using the Nasal Obstruction Symptom Evaluation scale

BACKGROUND

This study evaluated changes in nasal airway function following Le Fort I osteotomy with maxillary impaction according to the Nasal Obstruction Symptom Evaluation (NOSE) scale.

METHODS

This cohort study included 13 patients who underwent Le Fort I osteotomy with maxillary impaction. Nasal airway function was evaluated based on the NOSE scale preoperatively and at 3 months postoperatively. The change in the NOSE score was calculated as the preoperative score minus the postoperative score. If the normality assumptions for changes in the NOSE score were not met, a nonparametric test (the Wilcoxon signed-rank test) was used. Differences in NOSE score changes according to patient characteristics and surgical factors were evaluated using the Kruskal-Wallis test and the Mann-Whitney test.

RESULTS

Patients ranged in age from 18 to 29 years (mean±standard deviation [SD], 23.00±3.87 years). Three were men and 10 were women. Eleven patients (84%) had an acquired dentofacial deformity with skeletal class III malocclusion. The preoperative NOSE scores ranged from 40 to 90 (mean±SD, 68.92±16.68), and the postoperative NOSE scores ranged from 25 to 80 (53.84±18.83). The cohort as a whole showed significant improvement in nasal airway function following maxillary impaction (P=0.028). Eleven patients (84%) had either improved (n=8) or unchanged (n=3) postoperative NOSE scores. However, nasal airway function deteriorated in two patients. Patient characteristics and surgical factors were not correlated with preoperative or postoperative NOSE scores.

CONCLUSIONS

Nasal airway function as evaluated using the NOSE scale improved after maxillary impaction.

Does maxillary superior repositioning affect nasal airway function?

This study aimed to assess nasal airflow, nasal resistance, and the cross-sectional area of the nasal cavity in patients who have had maxillary superior repositioning (MSR). This is a cross-sectional study, and nasal airflow, nasal resistance, and the cross-sectional area of the nasal cavity were evaluated by rhinometry and acoustic rhinometry techniques in patients who had had MSR. Thirty-two patients were studied, and the mean (SD) MSR was 5.03 (1.61) (range 3-8) mm. There was a significant correlation between the mean MSR and the mean change in nasal airflow and nasal resistance (p=0.001 and p=0.005, respectively). There was also a correlation between MSR and the change in the cross-sectional area of the inferior concha (p=0.001), but there was no correlation between the mean MSR and the change in cross-sectional area of the isthmus (p=0.07). Nasal airflow increases when the mean MSR is less than 6.5mm, and when maxillary impaction is 6.5mm or more, nasal airflow decreases. It seems, therefore, that MSR of less than 6.5mm was associated with an improvement in nasal airflow. When maxillary impaction was more than 6.5mm, nasal airflow and the cross-sectional area of the nasal cavity decreased, and nasal resistance increased.

Clinical evaluation of submental intubation as an alternative airway management technique in midface osteotomy

BACKGROUND

The conventional endonasal intubation would not allow precise intra-operative assessment of the changes to the nasolabial soft tissue complex. Submental intubation allows accurate measurement of nasolabial soft tissue complex with no interference with the occlusion.

METHODOLOGY

A clinical prospective study was carried on 20 patients visiting the Oral and Maxillofacial Surgery department diagnosed of dentofacial deformity requiring orthognathic surgery. The patient were intubated by the submental route of anaesthesia. Intraoperatively time taken to perform intubation and bleeding during the surgery was noted. Post-operatively infection, presence or absence of any complications were noted along with the measurement of scar by Vancouver scar scale.

RESULTS

Out of 20 patients 17 patients required only maxillary osteotomies whereas 3 patients required bimaxillary osteotomy. The mean time taken for intubation was 5.68 ± 1.257 minutes. In all the cases the scar was measured as minimum. 2 patients showed infection at the site of submental intubation after 7th day while after 14th day there was no infection present. No other complication was noted. 19 out of 20 cases showed no interference during the procedure whereas in 1 case mild interference during mandibular movement.

CONCLUSION

The submental intubation is a very good alternative to nasotracheal intubation in the patients undergoing bimaxillary surgeries or maxillary surgeries. Submental intubation can be chosen whenever possible, as it is easy, takes little time and follow-up is simple, does not result in bleeding or other complications and more importantly does not result in any unaesthetic scar after 3rd month follow up.

Impact of Le-Fort I osteotomy on anatomical and functional aspects of the nasal airway and on quality of life

OBJECTIVES

Orthognathic surgery is a well-established procedure for skeletal deformities. Beneficial influences to the posterior airway space (PAS) have been described, but little is known about the subjective aesthetical and functional nasal aspects after orthognathic surgery. The aim of this study was to evaluate nasal airflow by anterior rhinomanometry and volumetric changes in the nasal airway space after mono- or bimaxillary surgery using cone-beam computed tomography (CBCT) and a new segmentation software. Furthermore, changes of patient's quality of life (QoL) should be assessed.

METHODS

Ten patients (9 skeletal class malformation III, 1 skeletal class malformation I) were included. CBCT images, rhinological inspections and anterior rhinomanometries were performed before (T0) and after surgery (T1). All patients completed the FROI-17, the ROE and the SF-36 questionnaires.

RESULTS

A significant postoperative gain for nasal airway volume compared with the baseline was shown (p < 0.014). No statistically significant differences between pre- and postoperative flow rates were found (p = 0.114). Pre- and postoperative cohorts did not differ in responses of disease-specific (ROE and FROI-17) and generic QoL questionnaires (SF-36).

CONCLUSION

Maxillary relocation surgery leads to a significant increase in nasal airway space. Subjectively, orthognathic patients did not experience any functional but psychosocial aspects after bimaxillary surgery.

A 3-Dimensional Analysis of Nasal Cavity Volume After Maxillary Le Fort I Osteotomy

PURPOSE

Two- and 3-dimensional studies on changes of the pharyngeal airway after a Le Fort I osteotomy have been conducted, but there are few studies on the change of nasal structure. The nasal cavity is the first passage through which air enters during respiration. Movement of the maxilla by Le Fort I osteotomy affects the shape of the nasal cavity and the shape of other parts of the airway. This study compared preoperative and postoperative changes of the nasal cavity volume after a maxillary Le Fort I osteotomy.

MATERIALS AND METHODS

Pre- and postoperative computed tomograms of 32 patients were assessed for nasal cavity volume according to the direction of maxillary movement.

RESULTS

Thirty-two patients (22 men and 10 women) were classified according to the direction of maxillary movement: maxillary impaction (group I; 8 men and 6 women) and maxillary impaction and advancement (group II; 14 men and 4 women). Nasal cavity volume was markedly decreased after the Le Fort I osteotomy in groups I and II. Group I showed a positive correlation between the ratio of impaction and the ratio of volume difference. Group II showed no correlation between the ratio of impaction or advancement and the ratio of volume difference.

CONCLUSION

Impaction and advancement of the maxilla decreased nasal volume.

Tomographic Analysis of the Impact of Mandibular Advancement Surgery on Increased Airway Volume

PURPOSE

This study aimed to quantify, using cone-beam computed tomography (CBCT) in patients who underwent a mandibular advancement surgery associated with genioplasty, three-dimensional changes in airway space and to evaluate whether these changes differ between men and women.

MATERIALS AND METHODS

Preoperative and 8-month postoperative CBCT scans of 38 patients aged 18-45 years of either sex and any ethnicity who underwent mandibular advancement surgery associated with genioplasty were analyzed using the Xoran software (Xoran Technologies, Ann Arbor, MI, USA). The linear distances gonion-gnathion (Go-Gn) and condylion-menton (Co-Me) were obtained. Airway volume was measured using the Dolphin Imaging software, version 11.0. Then, data were tabulated and analyzed using Student's t-test.

RESULTS

Mean patient age was 30.3 years; 39.47% were men and 60.63% were women. The mean Go-Gn distance was 72.05 mm before surgery and 78.56 mm after surgery, with a mean gain of 6.51 mm. The mean Co-Me distance was 113.47 mm before surgery and 119.89 mm after surgery, with a mean increase of 6.42 mm. Both differences were statistically significant. The mean volume of airway space was 17,272.92 mm3 before surgery and 24,173.74 mm3 after surgery, with a statistically significant mean increase of 6900.82 mm3. There was no statistically significant difference in mean volumetric gain between men (7566.69 mm3) and women (7456.69 mm3).

CONCLUSION

Mandibular advancement surgery results in significant increase of airway space, and there is no difference in airway volume between men and women.

Long-term influence of mandibular advancement on the volume of the posterior airway in skeletal Class II-patients: a retrospective analysis

In the past, maxillomandibular advancement has resulted in considerable improvement in the volume of the posterior airway space. The objective of the present study was to find out how mandibular advancement without maxillary involvement would affect the posterior airway space in patients with mandibular retrognathism. Cone-beam computed tomographic (CT) scans were done for 20 patients before, and six months after, mandibular advancement. Cephalometric analysis at both time points included 2-dimensional and 3-dimensional assessment of the upper airway. Eight men and 12 women presented a preoperative mean (SD) Wits value of 7.4 (1.54) mm, with an airway area of 7.11 (1.88) cm² and a volume of 14.92 (4.46) cm³. Six months postoperatively they showed a Wits value of 2.7 (0.41) mm, an airway area of 11.33 (3.49) cm², and a volume of 25.7 (6.10) cm³. There was a mean (range) enlargement of 59 (22-82) % of the area and 73 (29-108) % of the volume. A preoperative Wits value of 8mm or more correlated significantly with a larger increase of the posterior airway space (p=0.002). At the same time, an improvement in the Wits value of 4.5mm or more correlated significantly with an increase in volume (p=0.016). The effect of mandibular advancement on the posterior airway space was significant, and the volumetric effect seems to be even more relevant than the two-dimensional changes.

Nasal Airway Evaluation After Le Fort I Osteotomy Combined With Septoplasty in Patients With Cleft Lip and Palate

Septal deviation constitutes an important component of both esthetic deformity and airway compromise in patients with cleft lip and palate (CLP). The posterior parts of the nasal septum presented greater deviation than the anterior parts in patients with complete unilateral CLP. Le Fort I down-fracture provides better access to the nasal septum than intranasal incision during rhinoplasty, especially to the posterior part. This study objectively and subjectively evaluated the nasal function after Le Fort I osteotomy combined with septoplasty in patients with complete unilateral CLP. Twenty-three patients with complete unilateral CLP presenting with nasal obstruction and septum deviation were included (12—combined surgery group; 11—control group). Types of septum deviation in the patients were analyzed. Presurgical and 6-month-postsurgical acoustic rhinometry (AR) was performed for objective assessment; and the nasal obstruction symptom evaluation (NOSE) scale was used for subjective assessment. The authors used SPSS to compare the baseline and follow-up results. Acoustic rhinometry assessment showed improvements in the nasal minimal cross-sectional area (MCA), nasal resistance, and nasal volumes in 12 patients who received combined surgery. For the 2 groups, significant improvements in nasal breathing were documented (by NOSE scores) at 6 months after surgery. Simultaneous management of the maxillary dysplasia (Le Fort I osteotomy) and intranasal pathology (septoplasty) were effective for relief of nasal airway obstruction in patients with complete unilateral CLP. The combination of objective (AR) and subjective (NOSE scale) assessments allowed better evaluation of the nasal function.

Computational Fluid Dynamic Study of Nasal Respiratory Function Before and After Bimaxillary Orthognathic Surgery With Bone Trimming at the Inferior Edge of the Pyriform Aperture

PURPOSE

This study aimed to evaluate the influence of maxillary impaction orthognathic surgery on nasal respiratory function and the efficacy of bone trimming at the inferior edge of the pyriform aperture.

MATERIALS AND METHODS

The participants were 10 patients (3 male and 7 female patients) with mandibular prognathism who underwent bimaxillary orthognathic surgery with maxillary impaction. The surgical procedures performed were Le Fort I osteotomy with bone trimming at the inferior edge of the pyriform aperture and bilateral sagittal split osteotomy. Three-dimensional models of the nasal cavity were reconstructed from preoperative and postoperative computed tomography images. Furthermore, we remodeled the nasal valve region based on the postoperative models by adding a 1-mm and 2-mm stenosis to investigate the effects of bone trimming at the inferior edge of the pyriform aperture on the pressure effort. The 3-dimensional models were simulated with computational fluid dynamics, and the results of the pressure effort and the cross-sectional area (CSA) were compared for the anterior, middle, and posterior parts of the nasal cavity. The Wilcoxon signed rank test and Spearman rank correlation coefficients were used for statistical comparisons (P < .05).

RESULTS

In the preoperative and postoperative models, there were considerable correlations between the CSA and the pressure effort in each part of the nasal cavity. The postoperative pressure effort showed a tendency to decrease and the CSA showed a tendency to increase in each part of the nasal cavity. In four 2-mm stenosis models, the pressure effort in the anterior nasal cavity was larger than the preoperative pressure effort and the CSA of the anterior nasal cavity was smaller than the preoperative CSA.

CONCLUSIONS

Bone trimming at the inferior edge of the pyriform aperture appears to be useful for avoiding nasal respiratory complications with maxillary impaction.

Assessment of nasal septum after Le Fort I osteotomy with computer tomography

The purpose of this study was to evaluate the effects of Le Fort I osteotomy on nasal septum deviation and differences in left and right airway sizes, and to determine whether the nasal septum was affected by differences in the direction of movement. Forty patients underwent conventional Le Fort I osteotomy, and computed tomography (CT) was performed preoperatively, and 1 week and 1 year postoperatively. The nasal septum angle and airway area were measured at the anterior, middle, and posterior positions on the CT images Patients were divided into 2 groups depending on each difference in movement (impaction ≥5 mm or other; anterior movement or other; and impaction asymmetry or other). There were no significant differences in the nasal septum angle and the airway of all patients. Among the patient groups, there were no significant differences in the nasal septum angle and airway. We concluded that conventional LI osteotomy did not influence the nasal septum deviation or the left and right airway asymmetry. Differences in the method of moving the maxilla have not been shown to affect changes in the nasal septum.

Surgical correction of septal deviation after Le Fort I osteotomy

Background

The Le Fort I osteotomy is one of the most widely used and useful procedure to correct the dentofacial deformities of the midface. The changes of the maxilla position affect to overlying soft tissue including the nasal structure. Postoperative nasal septum deviation is a rare and unpredicted outcome after the surgery. There are only a few reports reporting the management of this complication.

Case Presentation

In our department, three cases of the postoperative nasal septum deviation after the Le Fort I osteotomy had been experienced. Via limited intraoral circumvestibular incision, anterior maxilla, the nasal floor, and the anterior aspect of the septum were exposed. The cartilaginous part of the nasal septum was resected and repositioned to the midline and the anterior nasal spine was recontoured. Alar cinch suture performed again to prevent the sides of nostrils from flaring outwards. After the procedure, nasal septum deviation was corrected and the esthetic outcomes were favorable.

Conclusion

Careful extubation, intraoperative management of nasal septum, and meticulous examination of pre-existing nasal septum deviation is important to avoid postoperative nasal septum deviation. If it existed after the maxillary osteotomy, septum repositioning technique of the current report can successfully correct the postoperative septal deviation.

Outfracture of the inferior turbinates during superior repositioning Le Fort I osteotomy with cone-beam computed tomographic analysis of the volume of the nasal cavity

We have investigated the volumes of the nasal cavities of 35 patients treated with superior repositioning Le Fort I osteotomy by analysing cone-beam computed tomography (CT) data with a 3-dimensional reconstruction program to correlate changes in the volume of the nasal cavity that were associated with the maxillary superior repositioning and the role of outfracture of the inferior turbinates. The patients were treated at the Pusan National Dental Hospital during the 14-month period January 2011-March 2012.. The patients were divided into two groups, the first of which consisted of 20 patients who had superior repositioning of 4mm or more with a mean superior movement of 5.2mm and outfracture of the inferior turbinates (outfracture group). The second group consisted of 15 patients who also had more than 4mm impaction with a mean superior movement of 5.0mm and for whom outfracture was not done (no outfracture group). Nasal symptoms were investigated preoperatively and 6 months postoperatively using the Nasal Obstruction Symptom Evaluation (NOSE) scale, and 3-dimensional volumetric analysis was made using cone-beam CT data to assess changes in nasal volume. There were significant differences between the groups in volumetric changes (V1-V2) (p=0.001) but no significant differences between the sexes. The volume of the nasal cavity in the outfracture group decreased by 20% after superior repositioning, but that in the no outfracture group decreased by 33%. Among the 20 patients in the outfracture group not one complained of nasal symptoms postoperatively. We conclude that outfracture of the inferior turbinates should be considered when the amount of superior movement of maxilla is more than 4mm.

Outcome assessment of 603 cases of concomitant inferior turbinectomy and Le Fort I osteotomy

This retrospective study assessed the outcome of 603 patients undergoing partial inferior turbinectomies (PIT) in association with Lefort I osteotomy. The study included 1234 patients from a single private practice; these patients had dentofacial deformities and underwent Lefort I osteotomy procedures. For the full patient group, 888 patients (72%) were women; in the turbinectomy group, 403 (67%) were women. The anteroposterior, transverse, and vertical dimensions of the mandible, maxilla, and occlusal plane of each subject were assessed, in addition to cephalometric analysis and determination of the presence or absence of temporomandibular joint disorders. PIT, when indicated, was performed after downfracture of the maxilla, providing access to the turbinates where approximately two thirds of the total turbinate volume was removed and septoplasty was completed if indicated. Hypertrophied turbinates causing significant nasal airway obstruction were present in 603 (49%) of the 1234 patients undergoing Le Fort I osteotomy. The results of this study showed that PIT performed simultaneously with Le Fort I osteotomy is a safe method of managing nasal airway obstruction related to hypertrophied turbinates with minimal complications.

Effects of maxillary advancement and impaction on nasal airway function

The effects of Le Fort I osteotomy on the nasal airway are controversial. This study aimed to evaluate nasal airway changes after Le Fort I. 25 patients underwent conventional Le Fort I osteotomy and were separated into three groups depending on the type of surgery they underwent. 11 patients needed maxillary impaction, 9 underwent maxillary advancement, and 5 had both maxillary impaction and advancement. Rhinological examinations, anterior rhinomanometry and acoustic rhinometry were carried out 1 week before surgery and 3 months after that. Wilcoxon and χ(2) tests were used for data analysis. The samples included 19 females and 6 males with a mean age of 22.4 ± 3.32 years. Rhinomanometric assessment showed that total nasal airflow was increased from 406 ± 202 ml/s to 543 ± 268 ml/s in all three groups. Significant decrease in nasal airway resistance was seen in all three groups. Acoustic rhinometry revealed a significant decrease in total nasal volume but an increase in the cross-sectional areas of isthmus nasi (IN) and inferior concha. The rhinomanometric measurements showed improvements in the total nasal airflow after Le Fort I osteotomy with alar base cinch suture in cases where the impaction was not higher than 5.5mm.

Orthodontic measurements and nasal respiratory function after surgically assisted rapid maxillary expansion: an acoustic rhinometry and rhinomanometry study

The present study sought to assess nasal respiratory function in adult patients with maxillary constriction who underwent surgically assisted rapid maxillary expansion (SARME) and to determine correlations between orthodontic measurements and changes in nasal area, volume, resistance, and airflow. Twenty-seven patients were assessed by acoustic rhinometry, rhinomanometry, orthodontic measurements, and use of a visual analogue scale at three time points: before surgery; after activation of a preoperatively applied palatal expander; and 4 months post-SARME. Results showed a statistically significant increase (p<0.001) in all orthodontic measurements. The overall area of the nasal cavity increased after surgery (p<0.036). The mean volume increased between assessments, but not significantly. Expiratory and inspiratory flow increased over time (p<0.001). Airway resistance decreased between assessments (p<0.004). Subjective analysis of the feeling of breathing exclusively through the nose increased significantly from one point in time to the next (p<0.05). There was a statistical correlation between increased arch perimeter and decreased airway resistance. Respiratory flow was the only variable to behave differently between sides. The authors conclude that the SARME procedure produces major changes in the oral and nasal cavity; when combined, these changes improve patients' quality of breathing.

Does cosmetic rhinoplasty affect nose function?

Objective. To evaluate the changes in nasal dimensions of healthy Iranian volunteered for cosmetic rhinoplasty after surgery using acoustic rhinometry. Methods. Pre- and postoperative nasal dimension of 36 cases undergoing cosmetic rhinoplasty were compared using acoustic rhinometry (AR), and the measured variables were distance to first and second constriction (d1, d2), first and second minimal cross-sectional area (MCA1, 2), and volume. Results. Mean age (SD) of cases were 24.63 (4.4) years. Septoplasty was performed in 12 cases (33.3%). After surgery, bilateral d1 and both MCA2 decreased significantly, while significant increase was observed in MCA1 postoperatively using decongestant. Cases with septoplasty experienced more increase in MCA1 and less constriction in MCA2 postoperatively. In cases with rhinoplasty alone, they received benefit from double osteotomy in MCA1. In either group of rhinoplasty with and without septoplasty, placing a strut was beneficial for patients. Discussion. The cross-sectional area of the nose is a major factor in the determination of airflow. Cosmetic rhinoplasty may generate a mix effect on nose function. Performing osteotomy may better help patients to save nasal patency, septoplasty is beneficial even in mildly deviated septums, and placing a strut may be beneficial in most of the cases.