A Three-Dimensional Evaluation of Postoperative Swelling following Orthognathic Surgery at 6 Months

Changes of the facial soft tissue after mandibular reconstruction using vascularized iliac flap

OBJECTIVES

To reveal the change patterns of the facial soft tissue after applying mandibular reconstruction.

MATERIALS AND METHODS

16 Patients with mandibular benign tumor were recruited in this retrospective study. For all patients, segmental mandibular osteotomy and concurrent reconstruction using vascularized iliac flap were conducted. The soft tissue thickness of patients' lower face was measured with CT scans before surgery, 1 week, 6 months and 1 year after surgery. The time-dependent changes of tissue thickness were analyzed.

RESULTS

The most significant tissue swelling was 28.86%, at 1 week after the surgery. The average increase of tissue thickness was 4.78 ± 5.30 mm across patient. After 1 year of the surgery, tissue thickness decreased to the level before operation or the level of the healthy side. The thickness of the low-density tissue fluctuated mildly, while the thickness of the high-density tissue fluctuated significantly. The disuse atrophy of the masseter occurred 1 week after the surgery, and was reversed after 1 year. The removal of the submandibular gland caused depression in submandibular area, which intensified over time.

CONCLUSION

Across patients, soft tissue thickness in the lower face after mandibular osteotomy and reconstruction increased significantly 1 week after the surgery, and decreased over time. After 1 year, tissue thickness went back to the pre-surgery level, where matched up with the healthy side.

CLINICAL RELEVANCE

We documented the change patterns of the facial soft tissue after mandibular reconstruction. These results can help improve the planning of virtual surgeries and the timing for aesthetic assessment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: ChiCTR2100054103.

Risk factors for postoperative facial swelling at 1 week after bimaxillary orthognathic surgery in Class III patients

OBJECTIVE

To quantify facial swelling at 1 week after Le Fort I osteotomy and bilateral sagittal splitting ramus osteotomy in Class III patients and to identify factors contributing to the swelling based on clinical, morphologic, and surgical variables.

STUDY DESIGN

Data from 63 patients were examined in this single-center, retrospective study. Facial swelling was quantitatively measured by superimposing computed tomography data taken in the supine position at 1 week and 1 year postoperatively and extracting the area of maximum intersurface distance. Age, sex, body mass index, thickness of subcutaneous tissue, and of masseter muscle, maxillary length (A-VRP), mandibular length (B-VRP), and posterior maxillary height (U6-HRP), surgical movement (ΔA-VRP, ΔB-VRP, ΔU6-HRP), drainage method, and usage of facial bandages were examined. Multiple regression analysis was performed using the above factors.

RESULTS

The median swelling at 1 week postoperatively was 8.35 IQR (5.99-11.47) mm. Multiple regression analysis revealed three factors that were significantly associated with facial swelling: Use of postoperative facial bandages (P=0.03), masseter muscle thickness (P=0.03), and ΔB-VRP (P=0.04).

CONCLUSION

Absence of a facial bandage, thin masseter muscle, and large horizontal mandibular movement are risk factors for facial swelling at 1 week postoperatively.

Evaluation of facial soft tissue asymmetric changes in Class III patients after orthognathic surgery using three-dimensional stereophotogrammetry

The aim of this study was to investigate changes in facial soft tissue asymmetry over time after orthognathic surgery in Class III patients using three-dimensional stereophotogrammetry. The study included 101 patients with a skeletal Class III malocclusion (72 female, 29 male; age range 19-53 years, mean age 28.6 years) who underwent orthognathic surgery. The minimum follow-up was 12 months. Three-dimensional photographs were acquired using the 3dMDtrio stereophotogrammetry system, and 21 anthropometric landmark positions were evaluated at three time points: before surgery (T0), 6 months (T1) and 12 months (T2) after surgery. Facial asymmetry was assessed and classified as follows: 0-2 mm, mild; 2-5 mm, moderate;> 5 mm, severe. The average distance for whole face asymmetry differed between T0 (median 0.76 mm) and T1 (median 0.70 mm); however, there was no statistically significant difference at any time point. The chin volume asymmetry score differed significantly between T0 (median 1.11 mm) and T1 and T2 (median 1.08 mm for both; P < 0.001 and P = 0.001, respectively), but not between T1 and T2 (P = 0.061). The study findings indicate that the asymmetry of the facial soft tissues has the potential to return after 6 months, without reaching the baseline.

Do patients treated with Invisalign have less swelling after orthognathic surgery than those with fixed orthodontic appliances?

INTRODUCTION

Patients treated with perioperative Invisalign for orthognathic surgery may experience less postoperative swelling than those with fixed appliances because of a lack of mucosal irritation from bonded brackets and wires. The aims of this study were to (1) compare facial swelling after orthognathic surgery in subjects with Invisalign to those with fixed appliances using 3-dimensional (3D) subtraction imaging and (2) determine if the type of operation influences differences in swelling.

METHODS

This is a retrospective case-control study. To be included in the case group (Invisalign), patients had to have had: (1) LeFort I and/or bilateral sagittal split osteotomies, with or without genioplasty, (2) perioperative orthodontic treatment using Invisalign, and (3) 3D photographs at postoperative timepoints 1 week (T1), 3-4 weeks (T2), and 5-7 weeks. A sex and operation-matched control group with fixed appliances (standard) was also included. The primary outcome variable was the volume of facial swelling, measured by subtraction imposition of the T1 and T2 3D images using reference images (5-7 weeks).

RESULTS

Twenty-two subjects (36% female; mean age 20.7 ± 3.15 years) were included: Invisalign (n = 11) and standard (n = 11). For each group, 7 subjects had 1 operation (LeFort I or bilateral sagittal split osteotomies), and 4 had bimaxillary surgery ± genioplasty. At T1, the Invisalign group had significantly less swelling than the standard group (17.52 ± 10.79 cm³ vs 37.53 ± 14.62 cm³; P <0.001). By T2, the differences were no longer significant (6.62 ± 5.19 cm³ for Invisalign; 5.85 ± 4.39 cm³ for standard, P = 0.728).

CONCLUSION

Subjects with Invisalign had significantly less facial swelling in the first postoperative week than those with fixed appliances.

Reproducibility of Three-Dimensional Volumetric Measurement of Periocular Tumor Models

INTRODUCTION

In this study, we measured the volume of customized tumor models in the periocular area using three-dimensional (3D) stereophotogrammetry and evaluated the reproducibility of these measurements.

METHODS

Five tumor models of different colors and sizes were placed in different periocular positions, and 3D facial images were obtained from 68 healthy adult volunteers. Subsequently, the volumes of the tumor models were measured, and the intra- and interrater reproducibility was assessed.

RESULTS

The gray 6 mm model revealed the highest reliable measurements in both Caucasians (intra- and interrater intraclass correlation coefficients of 0.981 and 0.899, mean absolute difference of 1.446 and 3.327 mm³, relative error measurement of 3.497% and 8.120%, technical error of measurement of 1.450 and 3.105 mm³, and relative technical error of measurement of 3.506% and 7.580%) and Asians (0.968 and 0.844, 1.974 and 4.067 mm³, 4.772% and 9.526%, 2.100 and 4.302 mm³, and 5.076% and 10.076%, respectively). The highest reliability of measurements in the lateral upper eyelid (0.88 and 0.95, 4.042 and 3.626 mm³, 9.730% and 9.020%, 5.714 and 3.358 mm³, and 9.730% and 8.350%, respectively) and medial upper eyelid (0.81 and 0.89, 4.313 and 4.226 mm³, 9.730% and 9.020%, 6.098 and 4.069 mm³, and 9.730% and 8.350%, respectively) with eyes closed was evident in Caucasians, while the same trend (0.841 and 0.815, 2.828 and 3.757 mm³, 9.860% and 9.840%, 4.052 and 4.308 mm³, and 9.860% and 9.740%, respectively) was observed in Asians in the medial canthus with eyes closed.

CONCLUSIONS

This study confirms, for the first time, the high reliability of periocular tumor volume measurements using 3D stereophotogrammetry, suggesting its feasibility for eyelid tumor measurement. Further trials are required to investigate its clinical use for documentation and follow-up of different eyelid tumors.

Improved lip esthetics in patients with skeletal Class III malocclusion and facial asymmetry after isolated mandibular orthognathic surgery

INTRODUCTION

Asymmetry of the lips severely affects facial esthetics and is often one of the chief complaints of orthognathic patients, especially those with Class III malocclusion. The objectives of this study were to investigate the changes in lip symmetry in patients with mandibular prognathism and deviation and the relationships between jaw hard tissue and lip soft-tissue changes.

METHODS

Three-dimensional facial scan and cone-beam computed tomography scan data of 30 orthodontic-orthognathic patients treated with bilateral sagittal split ramus osteotomy were combined to conduct the research. Paired-sample t test and Pearson correlation coefficient were applied to compare the differences in the same variable before and after the orthognathic surgery and the potential correlations between the changes in hard and soft variables. To explore the important hard tissue variables influencing the lip soft-tissue changes, linear regression analysis was performed.

RESULTS

Although there was significant upper lip asymmetry presurgery, the upper lip asymmetry was corrected postsurgery. Surgical correction of the mandibular deviation was also accompanied by lengthening of the bilateral philtrum crests. Improvement in lip asymmetry and lengthening of the philtrum crests were primarily related to the transverse correction of the mandible rather than sagittal changes. The corresponding prediction formulas were established.

CONCLUSIONS

The isolated mandibular bilateral sagittal split ramus osteotomy surgery can substantially improve the upper and lower lip asymmetry in patients with mandibular prognathism and deviation, but one should be wary of the unesthetic effects associated with lengthening of the philtrum crests.

Scleral exposure changes after Le Fort I maxillary advancement with vertical component in individuals with skeletal Class III malocclusion-A stereophotogrammetric image study

OBJECTIVE

This retrospective study aimed to evaluate inferior scleral exposure changes in Class III patients that underwent orthognathic surgery with Le Fort I osteotomy with and without vertical displacement.

MATERIALS AND METHODS

Preoperative and 6-months postoperative cephalograms and stereophotogrammetric images of 45 subjects (mean age:21.66±2.97 years) that underwent orthognathic surgery for Class III correction were retrieved. Subjects were divided into 3 groups: maxillary advancement-only (AO); maxillary advancement+impaction (AI), maxillary advancement+downfracture (AD). Exclusion criteria were mandibular-only surgery, occlusal canting, facial asymmetry, orbital surgery, and craniofacial syndrome. One investigator measured inferior scleral exposure on both sides using following landmarks: upper eyelid margin (A), inferior limbus (B) and lower eyelid margin (C). Distance between A and C was recorded as overall eye height (E), distance between B and C was recorded as inferior sclera exposure (S). S:E ratio in percentage was calculated to standardize sclera exposure relative to overall eye height. Wilcoxon signed-rank and Kruskal Wallis tests were used for statistical analysis (p<0.05).

RESULTS

Mean value of maxillary movements were: 4.21±1.82mm advancement in AO; 5.08±2.18mm advancement and 2.33±0.99mm impaction in AI; 3.95±1.45mm advancement and 3.1±0.71mm downfracture in AD. Change in reduction of scleral exposure was significant in all groups (p<0.05). AI group bilaterally and AO group right side had highest differences (-4.96±4.86, -6.09±4.21, -4.99±3.23, respectively). There was no significant difference between groups in S:E ratio changes (p>0.05).

CONCLUSION

Intergroup comparisons showed no statistically significant difference, revealing similar reduction in all three groups despite the differences in the vertical movement variable.

Postoperative Edema Resolution Post-Orthognathic Triple Jaw Surgery: A Three-Dimensional Volumetric Analysis

PURPOSE

The final result following orthognathic surgery may be hidden for months due to postoperative swelling. However, no substantial evidence supports this time estimate. Our study aims to three-dimensionally quantify volumetric changes in facial edema following triple-jaw surgery.

MATERIALS AND METHODS

This was a retrospective, three-dimensional (3D) study of patients who underwent primary orthognathic triple jaw surgery (Le Fort I, Bilateral Sagittal Split Osteotomy (BSSO), and osseous genioplasty) by the senior author (DMS). Vectra 3D Software (Canfield, Fairfield, NJ) was used to assess and quantify volumetric changes between serial 3D photos. An inverse line of best-fit was plotted to assess reduction in postoperative facial edema. The effects of gender, age, body mass index, and tranexamic acid administration on swelling resolution were analyzed through mixed linear model analysis.

RESULTS

A total of 46 patients (198 images) met the study criteria. The equation for the inverse function line of best fit was y = -13.14ln (x) + 39.54 (P < 0.01). On average, 60% of the swelling resolved in 1 month, 84% after 6 months, and nearly 93% after 12 months. There were no significant differences in the rate of swelling resolution when accounting for age, gender, body mass index, or tranexamic acid administration.

CONCLUSIONS

Most facial edema resolved during the first month following triple jaw surgery, with significant reduction in swelling between 6 and 12 months postoperatively. After 1 year, approximately 10% of the initial edema remained.

Early recovery after surgery protocol in orthognathic surgery: a randomized, blind clinical study

A randomized, blind and prospective clinical trial was conducted to compare two clinical rehabilitation protocols in patients submitted to orthognathic surgery, during the first 60 days after surgery. Pain, edema, mandibular movement, masticatory efficiency and quality of life were evaluated. Nineteen (19) patients were separated into control and experimental groups. The control group consisted of 10 patients followed by oral and maxillofacial surgeons and submitted to a rehabilitation protocol that involved active and passive mouth opening exercises. The experimental group had 9 patients and followed the surgeons' protocol, in addition to an Early Recovery After Surgery (ERAS) protocol performed by speech therapists, and involving specific motricity exercises and lymphatic drainage. The Student's t-test was applied to compare the results, and the Fisher's exact test of independence, to analyze the quality of life and the masticatory efficiency variables. The statistical significance was set at 5% (p < 0.05) for all the tests. The results showed that the ERAS protocol made a positive difference in pain perception in the first 14 days. However, it did not improve the other variables. Although many variables showed no significant difference, it was concluded that the surgeons can delegate patient rehabilitation to qualified professionals, so that they can optimize their postoperative clinical time.

Three-dimensional changes in the location of soft tissue landmarks following bimaxillary orthognathic surgery

OBJECTIVES

We sought to determine the amount of three-dimensional (3D) movement of soft tissue landmarks in patients who underwent bimaxillary orthognathic surgery.

MATERIALS AND METHODS

We recruited 28 patients (11 women and 17 men), who had received one-piece Le Fort I osteotomy with maxillary advancement and impaction, and bilateral sagittal split ramus osteotomy for mandibular setback. The 3D images were acquired 1-7 days before surgery and at least 6 months after surgery using stereophotogrammetry. We recorded 50 coordinate measurements and correlated the movements between soft and hard tissues. Paired samples t‑test, independent samples t‑test, and Pearson's correlation analysis were used for statistical analysis.

RESULTS

Patients' ages ranged from 17-31 years (mean 20.4 ± 3.0 years). The mean advancement and impaction of the maxilla was 4.7 ± 1.2 and 2.2 ± 1.0 mm, respectively. The mean setback of the mandible was 4.2 ± 1.6 mm. Menton (Me) moved significantly closer to the midsagittal plane, and the bilateral alare (Al) and alar curvature (Ac) moved laterally. In addition, pronasale (Prn), bilateral Al, Ac, subnasale (Sn), subspinale (Ss), labiale superior (Ls), sublabiale (Sl), pogonion (Pog), and Me moved upwards. The bilateral cheek bone (Cbp), Al, Ac, Prn, Sn, Ss, Ls, and stomion (Sto) moved forward. Li, Sl, Pog, and Me moved backward. Interestingly, poor correlation was found between soft tissue landmarks and hard tissue movements.

CONCLUSION

We observed 3D coordinate changes in several soft tissue landmarks in the middle and lower thirds of the face. The results of this study may be useful for estimating postoperative changes in similar patients.

Validating three-dimensional imaging for volumetric assessment of periorbital soft tissue

Purpose: To evaluate the accuracy and interobserver variability of three-dimensional (3D) stereophotogrammetric imaging for volumetric assessment in the periorbital region and to propose a protocol for measurement. Methods: A cross-sectional study was performed. Fifty-eight normal adult subjects had photographs taken using the VECTRA M3 imaging system on two separate occasions at a single center teaching hospital. The primary study outcome measurement was mean volume change in the periorbital region, using different methods of image analysis with the following variables: registration method, eyes open or closed, eyelids measured separately or together, extension of area measured to include mid-face. Accuracy was defined as the agreement between paired images with no measured change in volume (0 mL). The agreement between two independent observers was assessed using Bland-Altman plots. Results: There was a statistically significant difference (P < .0001) between the different methods of measurement, with registration of images having the most effect (partial eta squared 0.229). A mean change in volume of 0.11 ± 0.13 mL was reported for the most accurate method. Agreement between observers was confirmed (highest Intraclass Correlation Coefficient 0.63). Conclusions: Assessment of volumetric change in the periorbital region using 3D image reconstruction is accurate with good interobserver repeatability and is suitable for clinical use. A protocol for data acquisition using the VECTRA M3 is proposed. 3D image reconstruction holds promise to enable diagnosis, treatment monitoring, and surgical outcome evaluation in ocular adnexal disease.

Electromyographic, Ultrasonographic, and Ultrasound Elastographic Evaluation of the Masseter Muscle in Class III Patients Before and After Orthognathic Surgery

PURPOSE

The aim of this study was to examine changes in the electromyographic activity, thickness, width, and hardness of the masseter muscle from before to after orthognathic surgery.

MATERIAL AND METHODS

The study included 15 patients with Class III dentofacial deformities who were treated with combined orthodontic and orthognathic surgery. Fifteen individuals with normal occlusion and no signs or symptoms of temporomandibular joint dysfunction were used as controls. All records were obtained bilaterally in the study group before surgery (T1), at 3 months after surgery (T2), and in the control group (CG) while at rest and in maximum voluntary contraction (MVC).

RESULTS

There was no difference in resting masseter muscle activity between T1, T2, and CG. Resting thickness and width of the masseter muscle did not differ significantly between T1 and T2. MVC masseter muscle activity and thickness increased significantly and width decreased significantly from T1 to T2 but did not reach CG values. Muscle hardness increased from T1 to T2.

CONCLUSIONS

The authors' findings indicate that despite improved muscle activity and dimensions, postoperative 3 months is still early period for adaptation of the masseter muscles to the new occlusion and skeletal morphology.

The effect of manual lymphatic drainage on patient recovery after orthognathic surgery-A qualitative and 3-dimensional facial analysis

OBJECTIVE

The aim of this study was to investigate the effect of manual lymphatic drainage (MLD) on postoperative facial swelling and pain.

STUDY DESIGN

A randomized, single-center, prospective, 2-arm clinical trial with blinded endpoint assessment was set up. Patients were enrolled from the Maxillofacial Department of the Ghent University Hospital (Belgium) between January 2015 and March 2018. Both the intervention group (n = 13) and the control group (n = 13) received the same postoperative care; in addition, the intervention group underwent 6 sessions of MLD after orthognathic surgery. Three-dimensional facial scans were performed and questionnaires administered on postoperative days 3, 7, 14, 30, 90, and 180. A linear mixed model was performed, and statistical significance was assumed at the 5% level.

RESULTS

In total, 26 patients (mean age 29 years; range 16-57 years) were included for statistical analysis. A faster decrease in swelling in the intervention group was observed on 3-dimensional scans. Furthermore, patients receiving MLD reported reduction in swelling and pain within the first month after surgery. However, no statistically significant difference could be detected in these observations (P > .05).

CONCLUSIONS

Within the limitations of this study, no statistically significant difference could be found between patients treated with or without MLD after orthognathic surgery with regard to swelling and pain.

3D Analysis of Facial Morphology of a Colombian Population Compared to Adult Caucasians

Objective:  The purpose of this study involves describing the facial morphology of a Colombian population with three-dimensional (3D) imaging, and comparing their facial morphology with the Caucasian to create a database for this ethnicity.

Materials and Methods:  The study, which included 135 subjects selected from the Valle University in Cali, Colombia, and 535 Caucasian subjects selected from the FaceBase–Data (1U01DE024449–01), was funded by the National Institute of Dental and Craniofacial Research. All images were taken in the natural head position (NHP) and captured using a stereo-photogrammetric camera system (3dMDface) to obtain a 3D image of each patient. The subjects were between 19 to 31 years of age, with a normal body mass index (BMI), and no craniofacial deformities. All images were plotted and analyzed using the 3dMDVultus software to calculate linear and angular measurements. Standard deviation (SD) and means were calculated for each measurement and analyzed using t -test for different samples.

Results:  The Hispanic population had wider eyes, more protruded upper and lower lips, wider face, and greater mandibular width. Caucasian females had a more acute full profile, larger middle third, and less protrusive lips. Understanding the facial morphology of different populations would help to establish a better diagnosis and treatment planning for each ethnicity.

Conclusions:  From this study, the following conclusions may be drawn:

1. The mean values of Colombian males showed greater measurements than females in the majority of measurements.

2. Caucasian females had a more acute full profile, larger middle and lower third, and less protrusive lips.

3. This study showed significant ethnic differences in the linear and angular measurements, showing us the importance of considering these findings in the diagnosis and treatment planning when a Hispanic population is involved. Soft tissue values should reflect the norms according to each ethnic population in order to achieve treatment goals.

Reliability of the Linear Measurement (Contact) Method Compared with Stereophotogrammetry (Optical Scanning) for the Evaluation of Edema after Surgically Assisted Rapid Maxillary Expansion

Many techniques have been developed to evaluate facial swelling after maxillofacial surgeries. Patients who undergo surgically assisted rapid maxillary expansion (SARME) develop facial edema more often than those who undergo minor oral surgeries. Reliable systems to assess soft tissue dimensions offer many advantages for documentation and treatment planning across surgical fields. (1) Background: The objective assessment of facial swelling is advantageous as it allows the evaluation of the effect of anti-inflammatory drugs. Therefore, this study aimed to compare the reliabilities of linear measurement method and optical scanning for the objective assessment of facial swelling after SARME. (2) Methods: Sixteen (12 women and 4 men) patients were enrolled. Linear measurements between guide points and facial scans were obtained for the left and right sides preoperatively and 1, 2, and 5 days after SARME. Preoperative values were subtracted from each post-operative value and the differences were compared between the two measurement methods. (3) Results: There were no statistically significant differences between the right and left sides at any time point in the measurements with either method. (4) Conclusions: Recently, stereophotogrammetry has been considered the first choice method for evaluating facial swelling. Furthermore, we found a strong correlation between volumetric analysis and linear measurement at all time points and for both sides.

A Cross-Sectional Study to Understand 3D Facial Differences in a Population of African Americans and Caucasians

Objective The purpose of this cross-sectional retrospective study was to use three-dimensional surface imaging to determine gender dimorphism and facial morphological changes from adolescence to adulthood in African American and Caucasian populations.

Materials and Methods Three-dimensional images were captured and the total sample size included 371 subjects. Images were combined using Rapidform 2006 Plus Pack 2 software to produce a male and female facial average for each population. Comparisons were conducted within the following categories: (1) gender comparison within each race, (2) adult and adolescent comparison within each race, and (3) adult and adolescent comparison between the races.

Results Adolescent gender comparisons within each race showed high percentages of similarity. However, adult females in both races showed more prominent periorbital, malar, and nasolabial regions and less prominent lower forehead, nose, and lower face compared with adult males of the same race. African American adult females showed increase in length and width of the face, increased nasal tip projection, and decreased periorbital regions compared with African American adolescent females. Welsh adult females had an increase in the nose and chin projection compared with Welsh adolescent females. Adult males of both races had increase in nose and chin projection, increase in length and width of the face, and decreased periorbital, malar, and nasolabial regions compared with adolescent males of the same race. African American adolescents had a wider alar base, more protrusive lips, and periorbital regions, and less prominent nose and chin compared with the Welsh adolescents. African American adults also had a wider alar base; more protrusive lips and periorbital regions; a broader face; and more retrusive chin, nose, nasolabial region; and lower forehead compared with Welsh adults.

Conclusions Few differences were noted between genders within the same racial groups during adolescence. However, changes became more distinct in adulthood. From adolescence to adulthood, facial morphologies were similarly matched within the gender for females; however, there were significant changes for males. Lastly, facial morphology patterns tend to be established early in life.

Evaluation of preferred lip position according to different tip rotations of the nose in class I young adult subjects

INTRODUCTION

The mouth plays an important role in the overall aesthetic appearance of the face. The aims of this study were to determine the optimal antero-posterior (AP) lip position relative to various rotations of the nasal tip and assess the impact of the nasolabial angle on facial aesthetics.

MATERIAL AND METHODS

Three-dimensional facial volumes, in motion, of one Caucasian male and one Caucasian female with a Class I malocclusion and an orthognathic profile were modified to alter the nasal tip rotation (3 rotations) and the AP lips position (6 positions). 72 generated models were created in two and three-dimensions. Generated models were rated online by 60 dentists, 60 orthodontists and 60 laypeople, using a Visual Analogue Scale. Scores were analysed according to lip position, rater's profession and gender.

RESULTS

General agreement was found between all groups on the most and least preferred lip positions. No differences between male and female raters were found. All raters were more influenced by the 3-dimensional rotating facial volume than by 2-dimensional angles. Similar angular values for the nasolabial angles were found in the most and least preferred profiles, showing that the most influential factor in facial aesthetics was the lip position, and stressing the need to evaluate each component of the nasolabial angle independently.

CONCLUSION

The lip position was the determinant factor in facial aesthetics with little influence of the nose tip rotation. Three-dimensional evaluation of the nose and lip were needed to establish a soft tissue-based treatment plan.

Volumetric Assessment of Pediatric Vascular Malformations Using a Rapid, Hand-Held Three-Dimensional Imaging System

The effect of percutaneous, surgical, and medical therapies for vascular malformations (VMs) is often difficult to quantify volumetrically using cross-sectional imaging. Volumetric measurement is often estimated with serial, expensive MRI examinations which may require sedation or anesthesia. We aim to explore whether a portable 3D scanning device is capable of rapid, accurate volumetric analysis of pediatric VMs. Using an iPad-mounted infrared scanning device, 3D scans of patient faces, arms, and legs were acquired over an 8-month study period. Proprietary software was use to perform subsequent volumetric analysis. Of a total of 30 unilateral VMs involving either the face, arms, or legs, 26 (86.7%) VMs were correctly localized by discerning the larger volume of the affected side compared to the normal contralateral side. For patients with unilateral facial VMs (n = 10), volume discrepancy between normal and affected sides differed compared with normal controls (n = 19). This was true for both absolute (60 cc ± 55 vs 15 cc ± 8, p = 0.03) as well as relative (18.1% ± 13.2 vs 4.0% ± 2.1, p = 0.008) volume discrepancy. Following treatment, two patients experienced change in leg volume discrepancy ranging from - 17.3 to - 0.4%. Using a portable 3D scanning device, we were able to rapidly and noninvasively detect and quantify volume discrepancy resulting from VMs of the face, arms, and legs. Preliminary data suggests this technology can detect volume reduction of VMs in response to therapy.

Mandibular Advancement Means Lower Facial Enlargement: A 2-Dimensional and 3-Dimensional Analysis

PURPOSE

Bilateral sagittal split osteotomy (BSSO) is frequently used to treat Class II malocclusion for functional and esthetic purposes, with expected changes in the profile. The goal of this study was to assess transversal changes in mandibular advancement by comparing 3-dimensional (3D) photogrammetric modifications and 2-dimensional (2D) radiographic enlargement.

MATERIALS AND METHODS

A cohort study was conducted of patients who underwent an isolated advancement BSSO (Obwegeser-Dal Pont II type) for a Class II malocclusion. All patients had 3D photogrammetric and 2D radiographic evaluations before and after surgery. Frontal cephalograms were used to measure the evolution of bigonial distance (BGD) and 3D photographs were used to measure the evolution of cutaneous BGD (CBGD).

RESULTS

Fourteen patients were included. Mean mandibular advancement was 6 mm. BGD (+6.1 mm; P < 10^-3) and CBGD (+4.2 mm; P = .0017) were significantly increased. The mean ratio of soft tissue response to transversal skeletal changes was 0.81.

CONCLUSION

This 2D and 3D analysis of transversal modifications shows that advancement with the BSSO is responsible for marked lower third facial enlargement. This parameter must be taken into account during the preoperative esthetic assessment to ensure the provision of pertinent information to the patient and the consideration of complementary surgical correction.

Different Dosages of Corticosteroid and Routes of Administration in Mandibular Third Molar Surgery: a Systematic Review

Objectives

The objective of the present systematic review was to test the hypothesis of no difference in facial swelling, pain and trismus after surgical removal of mandibular third molar with different dosages of corticosteroids and administration routes.

Material and Methods

A MEDLINE (PubMed), Embase database and Cochrane Library search in combination with a hand-search of relevant journals was conducted by including randomized controlled trials published in English until 1^st December 2017.

Results

Seven studies fulfilled the inclusion criteria. Considerable variation in the included studies prevented meta-analysis from being performed. Preoperative submucosal injection of corticosteroids significantly diminishes facial swelling, pain and trismus compared with placebo. However, different dosages of corticosteroid and administration routes reveal contrary results indicating that administration of a higher dosage of corticosteroids do not necessarily cause a further decrease in facial swelling, pain and trismus.

Conclusions

Consequently, the optimal dosage of corticosteroids and administration route for diminishing postsurgical morbidity and improve quality of life after surgical removal of mandibular third molar is presently unknown. Therefore, further well-designed randomized clinical trials including a standardised protocol, patient-reported outcome measures and three-dimensional analysis of facial swelling is needed.

The Effectiveness of Saireito, a Traditional Japanese Herbal Medicine, in Reducing Postoperative Edema after Acquired Ptosis Surgery: A Prospective Controlled Trial

Background

Persistent edema is a common complication after the surgical treatment of blepharoptosis; however, no objective methods have been established for evaluating or treating this condition. We focused on the Japanese herbal medicine, Saireito, and evaluated its efficacy in reducing postoperative edema.

Methods

This was a prospective, nonrandomized, and controlled study. We evaluated the incidence of postoperative edema in a Control group using a subjective patient-assessed visual analog scales (VASs) to assess swelling, pain, itching, and local warmth and an objective surgeon-assessed VAS to evaluate swelling. Swelling was also assessed by an objective computer-based analysis of digital images. These methods were used to evaluate the effects of Saireito (8.1 g/day) for 8 weeks.

Results

A total of 49 patients and 80 eyelids were enrolled. Twenty-nine patients and 48 eyelids were assigned to the Control group, and 20 patients and 32 eyelids were assigned to the Saireito group. Our analysis of the Control group indicated that postoperative edema persisted for up to 8 weeks. On the other hand, the postoperative edema in the Saireito group was mostly eliminated at 8 weeks. The computer-based analysis of digital images showed that the edema tended to be reduced in the Saireito group compared with the Control group.

Conclusion

Saireito might be effective for reducing postoperative edema after blepharoptosis surgery and almost completely eliminated it at 8 weeks after surgery. This study was a preliminary and nonrandomized study; therefore, the randomized and placebo-controlled study will be needed in the next step.

The Impact of the Use of Kinesio Taping Method on the Reduction of Swelling in Patients After Orthognathic Surgery: A Pilot Study

BACKGROUND Orthognathic surgery (OGS) is associated with extensive surgical intervention within the soft and hard tissues of the facial region of the skull leading to inflammatory reactions. The presence of postoperative swelling indicates the accumulation of exudate or transudate; both these fluids occur in surgery. Massive swelling is a significant problem, because the tension of tissues intensifies pain sensations. The aim of the study was to evaluate the effectiveness of the kinesio taping method (KT) in patients after orthognathic surgery in the area of the facial skull in terms of eliminating postoperative swelling. MATERIAL AND METHODS The study of the impact of kinesiology tape applied after orthognathic surgery to the craniofacial area on the elimination of swelling was performed in sixteen patients who suffered from this complication after bilateral sagittal split osteotomy. RESULTS The swelling was shown to be reduced after KT; within the same study the differences were statistically significant between the left and right sides and for the same side (p<0.05). The application of the lymphatic kinesio taping method led to the reduction of tension in the affected area and restoration of proper lymphatic circulation in the region covered by swelling. This allows for the improvement of the blood and lymph microcirculation and activation of self-healing processes. CONCLUSIONS The analysis of the impact of the practical use of the lymphatic KT on complications after orthognathic surgery revealed that it had a beneficial effect on the reduction of swelling. The use of the KT method seems promising because it is simple to carry out, not traumatic, economical and rarely causes undesirable allergies.

A novel soft tissue prediction methodology for orthognathic surgery based on probabilistic finite element modelling

Repositioning of the maxilla in orthognathic surgery is carried out for functional and aesthetic purposes. Pre-surgical planning tools can predict 3D facial appearance by computing the response of the soft tissue to the changes to the underlying skeleton. The clinical use of commercial prediction software remains controversial, likely due to the deterministic nature of these computational predictions. A novel probabilistic finite element model (FEM) for the prediction of postoperative facial soft tissues is proposed in this paper. A probabilistic FEM was developed and validated on a cohort of eight patients who underwent maxillary repositioning and had pre- and postoperative cone beam computed tomography (CBCT) scans taken. Firstly, a variables correlation assessed various modelling parameters. Secondly, a design of experiments (DOE) provided a range of potential outcomes based on uniformly distributed input parameters, followed by an optimisation. Lastly, the second DOE iteration provided optimised predictions with a probability range. A range of 3D predictions was obtained using the probabilistic FEM and validated using reconstructed soft tissue surfaces from the postoperative CBCT data. The predictions in the nose and upper lip areas accurately include the true postoperative position, whereas the prediction under-estimates the position of the cheeks and lower lip. A probabilistic FEM has been developed and validated for the prediction of the facial appearance following orthognathic surgery. This method shows how inaccuracies in the modelling and uncertainties in executing surgical planning influence the soft tissue prediction and it provides a range of predictions including a minimum and maximum, which may be helpful for patients in understanding the impact of surgery on the face.

Effects of low-level laser therapy following surgical extraction of the lower third molar with objective measurement of swelling using a three-dimensional system

The aim of the present study was to evaluate and compare the effects of single- and two-dose low-level laser therapy (LLLT) on the postoperative swelling, trismus and pain of patients undergoing extraction of impacted mandibular third molars. In addition, edema was volumetrically measured with a 3dMD face system. A total of 45 patients were randomly divided into three treatment groups (15 patients in each group) as follows: Group 1, receiving routine management with ice application and serving as the control group; Group 2, receiving a single dose of LLLT immediately following surgery; and Group 3, receiving two doses of LLLT, immediately following surgery and on day 2 after surgery. In the present study, a gallium-aluminum-arsenide (0.3 W, 40 sec, 4 J/cm²) diode laser device was applied extraorally at the insertion point of the masseter muscle. The trismus, pain level and facial swelling of the patients were evaluated. The visual analog scale (VAS) was used to examine the pain degree, while a 3dMD face photogrammetric system was used to evaluate the volumetric alterations of the swelling. The results indicated no statistically significant differences in the mean swelling or trismus among the three groups. The mean VAS measurements did not differ significantly among the groups at postoperative day 2; however, significantly reduced VAS values were observed in Group 2 compared with Group 1 at postoperative day 7 (P<0.05). The present study demonstrated that, although single-dose or two-dose LLLT had beneficial effects on the swelling, trismus and pain level, a significant reduction was only observed in the pain level at postoperative day 7.

Three-Dimensional Anthropometric Evaluation of Facial Morphology

OBJECTIVES

The objectives of this study were to evaluate sexual dimorphism for facial features within Colombian and Mexican-American populations and to compare the facial morphology by sex between these 2 populations.

MATERIALS AND METHODS

Three-dimensional facial images were acquired by using the portable 3dMDface system, which captured 223 subjects from 2 population groups of Colombians (n = 131) and Mexican-Americans (n = 92). Each population was categorized into male and female groups for evaluation. All subjects in the groups were aged between 18 and 30 years and had no apparent facial anomalies. A total of 21 anthropometric landmarks were identified on the 3-dimensional faces of each subject. The independent t test was used to analyze each data set obtained within each subgroup.

RESULTS

The Colombian males showed significantly greater width of the outercanthal width, eye fissure length, and orbitale than the Colombian females. The Colombian females had significantly smaller lip and mouth measurements for all distances except upper vermillion height than Colombian males. The Mexican-American females had significantly smaller measurements with regard to the nose than Mexican-American males. Meanwhile, the heights of the face, the upper face, the lower face, and the mandible were all significantly less in the Mexican-American females. The intercanthal and outercanthal widths were significantly greater in the Mexican-American males and females. Meanwhile, the orbitale distance of Mexican-American sexes was significantly smaller than those of the Colombian males and females. The Mexican-American group had significantly larger nose width and length of alare than the Colombian group regarding both sexes. With respect to the nasal tip protrusion and nose height, they were significantly smaller in the Colombian females than in the Mexican-American females. The face width was significantly greater in the Colombian males and females.

CONCLUSIONS

Sexual dimorphism for facial features was presented in both the Colombian and Mexican-American populations. In addition, there were significant differences in facial morphology between these 2 populations.

The influence of dexamethasone on postoperative swelling and neurosensory disturbances after orthognathic surgery: a randomized controlled clinical trial

BACKGROUND

Orthognathic surgery is associated with considerable swelling and neurosensory disturbances. Serious swelling can lead to great physical and psychological strain. A randomized, prospective, controlled clinical trial was realized in order to evaluate the effect of a preoperative intravenous dexamethasone injection of 40 mg on postoperative swelling and neurosensory disturbances after orthognathic surgery.

METHODS

Thirty-eight patients (27 male and 11 female) patients, all with the indication for an orthognathic surgery, were enrolled in this study (mean age: 27.63 years, range: 16-61 years) and randomly divided into two groups (study group/ control group). Both groups underwent either maxillary and/or mandibular osteotomies, resulting in three subgroups according to surgical technique (A: LeFort I osteotomy, B: bilateral sagittal split osteotomy (BSSO), C: bimaxillary osteotomy). The study group received a single preoperative intravenous injection of 40 mg dexamethasone. Facial edema was measured by 3D surface scans on the 1st, 2nd, 5th, 14th and 90th postoperative day. Furthermore, neurosensory disturbances on the 2nd, 5th, 14th and 90th postoperative day were investigated by thermal stimulation.

RESULTS

Facial edema after LeFort I osteotomy, BSSO and bimaxillary osteotomy showed a significant decrease in the study group compared to the control group (P = 0.048, P = 0.045, P < 0.001). The influence of dexamethasone on neurosensory disturbances was not significant for the inferior alveolar nerve (P = 0.746) or the infraorbital nerve (P = 0.465).

CONCLUSIONS

Patients undergoing orthognathic surgery should receive a preoperative injection of dexamethasone in order to control and reduce edema. However, there was no influence of dexamethasone on reduction of neurosensory disturbances.

TRIAL REGISTRATION

DRKS00009033 .

A systematic review of soft-to-hard tissue ratios in orthognathic surgery. Part IV: 3D analysis - Is there evidence?

OBJECTIVE

The objective of this study was to determine the soft-to-hard tissue ratio using 3D analysis in different types of orthognathic surgery.

MATERIAL AND METHODS

A systematic search for relevant studies published in different languages through December 2016 was performed in the Medline, Embase, Lilacs, Scopus, and Science Direct databases. Additional studies were identified by reference analysis. The methodological quality of the included studies was evaluated using the method proposed by the Effective Public Health Practice Project. The level of evidence was assessed using the Level of Evidence (LOE) scale from the Oxford Center for Evidence-Based Medicine.

RESULTS

A total of 11 articles with 461 patients were included in the review, comprising 5 retrospective study and 6 prospective studies. The latter included 5 studies that performed anatomical area analyses of postoperative soft tissue results in the context of software-based planned surgeries without regard to hard tissues and 6 articles that presented analyses related to soft tissue in the preoperative and postoperative stage with certain points to be considered in hard tissues. The analysis of bias in the articles revealed a weak methodology in all included studies, which made it impossible to perform any type of comparison.

CONCLUSION

Bias governs many of the published studies related to 3D analysis. There are no data that can be applied to determine the soft-to-hard tissue ratio using 3D analysis in orthognathic surgery.

Effectiveness of Corticoid Administration in Orthognathic Surgery for Edema and Neurosensorial Disturbance: A Systematic Literature Review

PURPOSE

The aim of this systematic review was to evaluate the effect of corticosteroid (CS) administration on edema and neural regeneration in orthognathic surgery.

MATERIALS AND METHODS

A systematic literature search was conducted using the PubMed (Medline), Cochrane Library, and Scopus databases. The PICO approach was used, in which patients with skeletal dentofacial deformity composed the population; uni- or bimaxillary orthognathic surgery composed the intervention; administration versus no administration of CSs composed the comparison; and decrease in postoperative edema and neurosensory disorders composed the outcome. Thirty of 240 articles were selected and evaluated for their titles and abstracts in relation to the inclusion and exclusion criteria. After duplicate references were eliminated, 8 articles remained.

RESULTS

Patients who used CSs had lower rates of edema. In fact, after 4 months, there were no remarkable edema rates. These results suggest that neurosensory disorders resolved after 3 months. In addition, in the early and late periods, administration of CSs did not influence the regression of neurosensory disorders.

CONCLUSIONS

Administering CSs in orthognathic surgery improved the regression of facial edema independent of the dosage used but did not influence neurosensory disorders.

Changes of lip morphology following mandibular setback surgery using 3D cone-beam computed tomography images

BACKGROUND

The aims of this study are to evaluate the lip morphology and change of lip commissure after mandibular setback surgery (MSS) for class III patients and analyze association between the amount of mandibular setback and change of lip morphology.

METHODS

The samples consisted of 14 class III patients treated with MSS using bilateral sagittal split ramus osteotomy. Lateral cephalogram and cone-beam CT were taken before and about 6 months after MSS. Changes in landmarks and variables were measured with 3D software program Ondemand™. Paired and independent t tests were performed for statistical analysis.

RESULTS

Landmarks in the mouth corner (cheilion, Ch) moved backward and downward (p < .005, p < .01). However, cheilion width was not statistically significantly changed. Landmark in labrale superius (Ls) was not altered significantly. Upper lip prominence angle (ChRt-Ls-ChLt °) became acute. Landmarks in stomion (Stm), labrale inferius (Li) moved backward (p < .005, p < .001). Lower lip prominence angle (ChRt-Li-ChLt °) became obtuse (p < .001). Height of the upper and lower lips was not altered significantly. Length of the upper lip vermilion was increased (p =< 0.01), and length of the lower lip vermilion was decreased (p < .05). Lip area on frontal view was not statistically significantly changed, but the upper lip area on lateral view was increased and change of the lower lip area decreased (p > .05, p < .005). On lateral view, upper lip prominent point (UP) moved downward and stomion moved backward and upward and the angle of Ls-UP-Stm (°) was decreased. Lower lip prominent point (LP) moved backward and downward, and the angle of Stm-LP-Li (°) was increased. Li moved backward. Finally, landmarks in the lower incisor tip (L1) moved backward and upward, but stomion moved downward. After surgery, lower incisor tip (L1) was positioned more superiorly than stomion (p < .05). There were significant associations between horizontal soft tissue and corresponding hard tissue. The posterior movement of L1 was related to statistically significantly about backward and downward movement of cheilion.

CONCLUSIONS

The lip morphology of patients with dento-skeletal class III malocclusion shows a significant improvement after orthognathic surgery. Three-dimensional lip morphology changes in class III patients after MSS exhibited that cheilion moved backward and downward, upper lip projection angle became acute, lower lip projection angle became obtuse, change of upper lip area on lateral view was increased, change of lower lip area decreased, and morphology of lower lip was protruding. L1 was concerned with the lip tissue change in statistically significant way.

Facial soft tissue changes during the pre-pubertal and pubertal growth phase: a mixed longitudinal laser-scanning study

BACKGROUND/OBJECTIVES

Facial soft tissues changes during growth roughly tend to mimic the underlying hard tissues, but not completely. The aim of this mixed longitudinal study was to assess facial growth among pre-pubertal and pubertal subjects without malocclusion using a non-invasive three-dimensional laser scanning system.

SUBJECTS/METHODS

Fifty-nine subjects (30 females and 29 males) aged at baseline 5.4-8.9 years with normal occlusion were clustered into the younger, older pre-pubertal, and pubertal groups according to age and the absence/presence of a standing height growth spurt. Three-dimensional facial images were obtained using laser scanners for five consecutive years. Several transversal, sagittal, and vertical parameters were assessed for between and within group comparisons.

RESULTS

Significant overall changes of almost all parameters were seen within each group (P < 0.05) without any group differences (P > 0.05). The younger pre-pubertal group showed greater annual growth rates of lip prominence; both pre-pubertal groups showed greater rates in facial middle third height. The pubertal group showed greater annual rates in facial profile angle changes during the growth peak.

LIMITATIONS

A high standing height increment (7cm) was used as the threshold for subject allocation in the pubertal group.

CONCLUSIONS

Soft tissue facial growth has generally similar amounts and rates irrespective of the pubertal growth spurt. Pre-pubertal subjects show greater annual rates of facial middle third height changes while pubertal subjects show greater annual rates of chin protrusion.

Three-dimensional analysis of soft tissue changes in full-face view after surgical correction of skeletal class III malocclusion

OBJECTIVE

The objective of this study was to evaluate changes in soft tissue in full-face view because of surgical correction of skeletal Class III malocclusion, using 3-dimensional (3D) laser scanning.

METHODS

Twenty-seven subjects with skeletal Class III malocclusion [11 males; mean age (SD), 24.0 (5.7) years] underwent bilateral sagittal split ramus osteotomy for mandibular setback combined with Lefort I osteotomy with/without maxillary advancement. Twelve patients (group 1) had mandibular setback surgery, and the other 15 (group 2) had combination surgery. Lateral cephalograms and 3D facial scan images were assessed preoperatively and postoperatively. The facial widths upon superimposition of 3D facial images were measured in the same coordinates using a Rapidform 2006 system. Paired and independent t tests were done for statistical analysis.

RESULTS

The midface soft tissue broadened significantly above the cheilion plane postoperatively (P < 0.05). A larger change was observed nearer to subnasale plane, and a similar trend was seen among the horizontal planes in 1- or 2-jaw surgery groups. The widths from the exocanthion plane to the subnasale plane increased more in group 2 [mean (SD), 4.45 (2.45) mm, 8.71 (2.92) mm, and 7.62 (3.13) mm] than those in group 1 [mean (SD), 1.26 (0.97) mm, 1.84 (1.06) mm, and 1.35 (0.65) mm], and this difference was significant (P < 0.05). There was a decrease below the cheilion plane with mandibular setback between groups, but this difference was not significant.

CONCLUSIONS

The measurement method used here for the shape outline of the lateral parts of the face could provide quantitative data for the clinical evaluation and objective analysis of the human face in full-face view. The midface soft tissue in subjects with skeletal Class III malocclusion exhibited a greater increase in width after bimaxillary surgery procedures than mandibular setback-only surgery.

Three-dimensional facial simulation in bilateral sagittal split osteotomy: a validation study of 100 patients

PURPOSE

Three-dimensional (3D) virtual planning of orthognathic surgery in combination with 3D soft tissue simulation allows the surgeon and the patient to assess the 3D soft tissue simulation. This study was conducted to validate the predictability of the mass tensor model soft tissue simulation algorithm combined with cone-beam computed tomographic (CBCT) imaging for patients who underwent mandibular advancement using a bilateral sagittal split osteotomy (BSSO).

MATERIALS AND METHODS

One hundred patients were treated with a BSSO according to the Hunsuck modification. The pre- and postoperative CBCT scans were matched and the mandible was segmented and aligned. The 3D distance maps and 3D cephalometric analyses were used to calculate the differences between the soft tissue simulation and the actual postoperative results. Other study variables were age, gender, and amount of mandibular advancement or rotation.

RESULTS

For the entire face, the mean absolute error was 0.9 ± 0.3 mm, the mean absolute 90th percentile was 1.9 mm, and for all 100 patients the absolute mean error was less than or equal to 2 mm. The subarea with the least accuracy was the lower lip area, with a mean absolute error of 1.2 ± 0.5 mm. No correlation could be found between the error of prediction and the amount of advancement or rotation of the mandible or age or gender of the patient.

CONCLUSION

Overall, the soft tissue prediction algorithm combined with CBCT imaging is an accurate model for predicting soft tissue changes after mandibular advancement. Future studies will focus on validating the mass tensor model soft tissue algorithm for bimaxillary surgery.

Reliability and validity of measurements of facial swelling with a stereophotogrammetry optical three-dimensional scanner

Volume changes in facial morphology can be assessed using the 3dMD DSP400 stereo-optical 3-dimensional scanner, which uses visible light and has a short scanning time. Its reliability and validity have not to our knowledge been investigated for the assessment of facial swelling. Our aim therefore was to assess them for measuring changes in facial contour, in vivo and in vitro. Twenty-four healthy volunteers with and without an artificial swelling of the cheek were scanned, twice in the morning and twice in the afternoon (in vivo measurements). A mannequin head was scanned 4 times with and without various externally applied artificial swellings (in vitro measurements). The changes in facial contour caused by the artificial swelling were measured as the change in volume of the cheek (with and without artificial swelling in place) using 3dMD Vultus software. In vivo and in vitro reliability expressed in intraclass correlations were 0.89 and 0.99, respectively. In vivo and in vitro repeatability coefficients were 5.9 and 1.3 ml, respectively. The scanner underestimated the volume by 1.2 ml (95% CI -0.9 to 3.4) in vivo and 0.2 ml (95% CI 0.02 to 0.4) in vitro. The 3dMD stereophotogrammetry scanner is a valid and reliable tool to measure volumetric changes in facial contour of more than 5.9 ml and for the assessment of facial swelling.

Comparison of facial morphologies between adult Chinese and Houstonian Caucasian populations using three-dimensional imaging

The objective of this study was to compare the facial morphologies of an adult Chinese population to a Houstonian white population. Three-dimensional (3D) images were acquired via a commercially available stereophotogrammetric camera system, 3dMDface™. Using the system, 100 subjects from a Houstonian population and 71 subjects from a Chinese population were photographed. A complex mathematical algorithm was performed to generate a composite facial average (one for males and one for females) for each subgroup. The computer-generated facial averages were then superimposed based on a previously validated superimposition method. The facial averages were evaluated for differences. Distinct facial differences were evident between the subgroups evaluated. These areas included the nasal tip, the peri-orbital area, the malar process, the labial region, the forehead, and the chin. Overall, the mean facial difference between the Chinese and Houstonian female averages was 2.73±2.20mm, while the difference between the Chinese and Houstonian males was 2.83±2.20mm. The percent similarity for the female population pairings and male population pairings were 10.45% and 12.13%, respectively. The average adult Chinese and Houstonian faces possess distinct differences. Different populations and ethnicities have different facial features and averages that should be considered in the planning of treatment.

The accuracy of three-dimensional prediction planning for the surgical correction of facial deformities using Maxilim

The motivation for orthognathic surgery is to improve facial appearance and quality of life. This study aimed to validate a three-dimensional (3D) orthognathic planning programme (Maxilim) for predicting soft tissue changes following Le Fort I advancements. Cone beam computed tomography (CBCT) scans were taken before surgery (T(1)) and at 6-12 months after surgery (T(2)) for 13 patients. For each patient the 3D hard tissue changes between T(1) and T(2) were determined by CBCT superimposition on the cranial vault. Using Maxilim, each patient's skeletal movements were used to generate a 3D soft tissue prediction. The actual soft tissue mesh at T(2) was compared to the predicted mesh. The face was divided into areas: nose, right and left nares, right and left paranasal regions, upper and lower lip, and chin. The absolute distance between meshes for each region was calculated. A one-sample t-test showed the distances between the meshes for all of the areas were within 3 mm (P<0.05), except for the upper lip which was greater than 3 mm (P=0.577). Using Maxilim, 3D soft tissue predictions for Le Fort I advancements were clinically satisfactory in the regions assessed, but associated with marked errors around the region of the upper lip.

Evaluation of postoperative discomfort following third molar surgery using submucosal dexamethasone - a randomized observer blind prospective study

BACKGROUND

Surgical removal of impacted lower third molar is still the most frequent procedure done by Oral and Maxillofacial surgeons and is often associated with pain, swelling and trismus. These postoperative sequelae can cause distress to the patient as a result of tissue trauma and affect the patient's quality of life after surgery. Use of antiseptic mouthwashes, drains, muscle relaxants, cryotherapy, antibiotics, corticosteroids and physiotherapy seems to decrease postoperative discomfort. Among them corticosteroids are well-known adjuncts to surgery for suppressing tissue mediators of inflammation, thereby reducing transudation of fluids and lessening edema. The rationale of this study is to determine the effectiveness of submucosal injection of dexamethasone in reducing postoperative discomfort after third molar surgery.

PATIENTS AND METHODS

100 patients requiring surgical removal of third molar under local anesthesia were randomly divided into 2 groups, group I receiving 4 mg dexamethasone as submucosal injection and the control group II received no steroid administration. Facial swelling was quantified by anatomical facial landmarks. Furthermore, pain and patient satisfaction, as well as neurological score and the degree of mouth opening were observed from each patient.

RESULTS

Patients receiving dexamethasone showed significant reduction in pain, swelling, trismus, a tendency to less neurological complaints and improved quality of life compared with the control group.

CONCLUSIONS

Submucosal injection of dexamethasone is more efficient to manage postoperative discomfort after removal of third molars compared to no steroid administration.

Three-dimensional evaluation of soft tissue changes in the orofacial region after tooth-borne and bone-borne surgically assisted rapid maxillary expansion

OBJECTIVES

This study seeks to three-dimensionally assess soft tissue changes in the orofacial region following tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME).

MATERIALS AND METHODS

This prospective cohort study included 40 skeletally mature patients with transverse maxillary hypoplasia. A tooth-borne distractor (Hyrax) was used for expansion in 25 patients. In the remaining 15, a bone-borne distractor (transpalatal distractor, TPD) was used. Cone beam computed tomography (CBCT) scans were acquired before treatment (T0) and 22 months later (T1). 3D models were constructed from CBCT data and superimposed using voxel-based matching. Distance maps between the superimposed 3D models were computed to evaluate the degree of skeletal and soft tissue changes in the maxillary region.

RESULTS

Distance maps showed negative distances (mean -1.25 (±1.5) mm) in the middle of the upper lip, indicating posterior repositioning of this area. The cheek region showed positive changes (mean 1.66 (±1.1) mm), reflecting the underlying increase in maxillary width. There was no significant difference between the two groups in all measured distances (p > 0.05). Retro-positioning of the upper lip accompanied skeletal remodeling in the anterior alveolar region at a mean ratio of 88 %, while the cheek region followed 32 % of the alveolar expansion.

CONCLUSION

Soft tissue changes following SARME include posterior repositioning of the upper lip and increased projection of the cheek area. These changes were comparable between bone-borne and tooth-borne appliances.

CLINICAL RELEVANCE

This study provides clinicians with more information over the expected orofacial soft tissue changes following SARME.

Fracture depth and delayed contour deformity in frontal sinus anterior wall fracture

OBJECTIVES

The choice to manage isolated frontal sinus anterior wall fractures without the involvement of nasofrontal outflow tract is mainly based on aesthetic concern and depends largely on surgeons' preferences. Minimally depressed anterior wall fractures can be monitored by observation only with little risk of long-term morbidity and contour deformity. The purposes of this study were to evaluate the course of a nonoperated depressed frontal sinus anterior wall fracture and to identify the cutoff value of anterior wall displacement requiring surgical correction.

MATERIALS AND METHODS

A retrospective chart review of 51 nonoperated isolated frontal sinus anterior wall fractures was performed. The depth and area of each fracture were measured by computed tomographic scans. Medical records were carefully reviewed to identify the delayed complications or contour changes.

RESULTS

The mean fracture depth and size were 3.9 mm and 352 mm(2), respectively. Patients who had a fracture depth of 4 mm or less did not develop late depressive contour changes of the skin. However, 7 patients who each had a fracture depth of more than 4 mm developed mild contour changes during the months of follow-up. The delayed contour change was associated with fracture depth (P < 0.01), but the fracture area was not considered as an independent factor for delayed contour deformity (P > 0.05).

CONCLUSIONS

The presence of depressive contour changes on the skin is an indication for surgical correction of the frontal sinus fracture. Mildly displaced isolated frontal sinus anterior wall fractures can be observed if the fracture depression is less than 4 mm.