Three-dimensional changes in lip vermilion morphology of adult female patients after extraction and non-extraction orthodontic treatment

Comparative Analysis of Dynamic Esthetic Characteristics in Spontaneous Smiles Among Hani and Han Youths in Yunnan Province, China

OBJECTIVE

The aim of this study is to examine the dynamic esthetic characteristics of spontaneous smiles in Hani and Han youths in Yunnan Province.

METHODS

Employing a multistage stratified cluster random sampling approach, participants from the Hani and Han ethnic groups in Yunnan Province were recruited. Digital videography was used to capture facial characteristics at both rest and during spontaneous smiles. Subsequently, selected images were analyzed for dynamic esthetic parameters concerning the lips, teeth, and gingiva using image measurement software.

RESULTS

The study included youths from the Hani (n = 68) and Han (n = 59) ethnic groups in Yunnan Province. During spontaneous smiles, the exposure of maxillary central incisors was more pronounced compared with maxillary lateral incisors and canines in both ethnic groups. Variations in gingival display of central incisors were observed among males in the 2 ethnic groups (P < 0.05). The mobility of the mouth corner's width was significantly greater in Han males compared with Hani males (P < 0.05). Conversely, the width of the mouth corner during spontaneous smiles was greater in Hani females than in Han females (P < 0.05). Regarding the relationship between the gingival line and the upper lip, the unexposed type was predominant among males of both ethnicities, whereas the parallel type was predominant among females. Parallel and straight smile arcs were commonly observed among participants from both ethnicities.

CONCLUSION

The dynamic esthetic characteristics of the lips, teeth, and gingiva exhibit similarities between the youth of Hani and Han ethnicities in Yunnan Province. However, notable differences in certain dynamic smile esthetic traits exist between the sexes.

A retrospective comparative cephalometric evaluation of non-extraction multiloop edgewise archwire and bicuspid extraction therapies in anterior open bite treatment

OBJECTIVES

This study aimed to compare treatment efficacy and cephalometric outcomes between extraction and non-extraction MEAW therapies in non-growing open-bite patients.

MATERIALS AND METHODS

22 Multiloop Edgewise Archwire MEAW patients (11 males, 11 females) and 15 bicuspid extraction patients (3 males, 12 females) were selected according to a strict inclusion criterion. Comprehensive data collection related to age, sex, Cervical Vertebral Maturation CVM staging, and severity of the Anterior Open Bite AOB (1 = 0-1 mm; 2 = 1-2 mm; 3 = > 2.1 mm) was performed independently and in duplicate by 2 examiners. Each included patient's pre and post-treatment lateral cephalograms were traced and compared. The primary outcomes assessed were related to the efficacy of treatment: treatment duration and time needed to achieve a positive overbite. The secondary outcomes assessed were related to the post-treatment changes in cephalometric measurements between the groups. Descriptive statistics, Mann-Whitney U test, unpaired student's t-test, and Chi-squared were used for data analysis.

RESULTS

The mean change in open bite closure was 3.07 ± 2.07 mm in the MEAW group and 3.03 ± 2.28 mm in the extraction group (P > 0.05). MEAW therapy was 31% faster (118 weeks) than extraction therapy (171 weeks, P = 0.004). MEAW appliance showed a significantly shorter duration for open bite closure (71.82 ± 29.57 weeks) compared to the extraction group (127.25 ± 51.97 weeks, P = 0.002). A greater decrease in the U1-SN was seen in the extraction group (-8.70 ± 6.49°), compared to the MEAW group (-2.56 ± 7.36°, P = 0.047). The IMPA angle showed a greater decrease in the extraction group (-8.30 ± 8.85°) compared to the MEAW group (-0.90 ± 6.50°, P = 0.032). The (L6-MP perp) increased in the extraction group by (1.98 ± 3.43 mm), while decreased in the MEAW group (-0.43 ± 1.38 mm, P = 0.023).

CONCLUSION

In anterior open bite cases with bicuspid extraction, achieving a positive overbite typically involves retroclining and uprighting the upper and lower incisors (drawbridge effect). In contrast, the MEAW appliance focuses on uprighting the entire dentition and intruding the posterior teeth, often leading to shorter treatment durations.

CLINICAL RELEVANCE

The MEAW appliance's biomechanical advantage in uprighting posterior teeth in open bite cases may shorten treatment duration for correcting open bite malocclusion.

Craniofacial identification standards: A review of reliability, reproducibility, and implementation

There are numerous anatomical and anthropometrical standards that can be utilised for craniofacial analysis and identification. These standards originate from a wide variety of sources, such as orthodontic, maxillofacial, surgical, anatomical, anthropological and forensic literature, and numerous media have been employed to collect data from living and deceased subjects. With the development of clinical imaging and the enhanced technology associated with this field, multiple methods of data collection have become accessible, including Computed Tomography, Cone-Beam Computed Tomography, Magnetic Resonance Imaging, Radiographs, Three-dimensional Scanning, Photogrammetry and Ultrasound, alongside the more traditional in vivo methods, such as palpation and direct measurement, and cadaveric human dissection. Practitioners often struggle to identify the most appropriate standards and research results are frequently inconsistent adding to the confusion. This paper aims to clarify how practitioners can choose optimal standards, which standards are the most reliable and when to apply these standards for craniofacial identification. This paper describes the advantages and disadvantages of each mode of data collection and collates published research to review standards across different populations for each facial feature. This paper does not aim to be a practical instruction paper; since this field encompasses a wide range of 2D and 3D approaches (e.g., clay sculpture, sketch, automated, computer-modelling), the implementation of these standards is left to the individual practitioner.

Quantification and visualization of the tooth extraction effects on face with spatially dense geometric morphometrics

PURPOSE

To apply geometric morphometrics and multivariate statistics to evaluate changes of the face for female Chinese patients who underwent orthodontic treatment with different type of anchorage control.

METHODS

Forty-six adult female patients were enrolled including 33 four first premolar extraction cases (17 patients with mini-implants for maximum anchorage control and 16 patients without mini-implants) and 13 non-extraction cases with minimum treatment duration of 15 months. Spatially dense correspondence was established among all the images The pre-and post-treatment average faces of the two extraction groups and the non-extraction group were generated. Partial least squares regression was used to test the statistical significance of the effects of treatment for different anchorage choice.

RESULTS

The upper and lower lips were retruded significantly after treatment in the extraction groups. In the maximum anchorage control group, the temple and cheek were depressed by approximately 1 mm, and the zygomatic regions were increased in the mid-face. However, these changes were not statistically significant. In comparison, no statistically significant facial changes occurred in the non-extraction group.

CONCLUSIONS

The anchorage choice and the removal of four first premolar extraction influence lip shape as well as the perioral regions. However, extraction treatment does not impact the appearance of the cheeks and temples on a statistically level, as compared to orthodontic treatment without premolar extractions. Spatially dense geometric morphometric facilitates comprehensive treatment effect quantification and visualization on the full facial changes for improving orthodontic outcome evaluation.

Analyzing the effects of tooth extraction on the lip in orthodontic treatment

INTRODUCTION

The aim of this study was to analyze changes occurring in the lip and facial soft-tissue profile after fixed orthodontic treatment, with or without tooth extraction, in patients with dental class II malocclusion.

MATERIALS AND METHODS

Measurements were made on cephalometric films of 75 individuals with dental class II malocclusion before and after fixed orthodontic treatment. The patients were divided into three groups: no extraction, extraction of upper two premolars, or extraction of four premolars. The parameters measured were: basic upper lip thickness (BULT), vermilion upper lip thickness (VULT), upper lip inclination (ULI), basic lower lip thickness (BLLT), vermilion lower lip thickness (VLLT), lower lip inclination (LLI), face axis angle (Ba-N/PtmGn), labiomental angle, facial convexity angle, and total face convexity angle. The results were analyzed statistically using the Wilcoxon, Kruskal-Wallis, and Mann-Whitney U tests.

RESULTS

It was found that the VULT value in the group with no extraction was lower than the four-extraction group (P = 0.001; P < 0.05). The VULT value in the upper-two extraction group was significantly lower than that in the four-extraction group, and the Ba-N/PtmGn in the no-extraction group was lower than that in the four-extraction group (P = 0.001; P < 0.05).

CONCLUSIONS

These findings suggest that tooth extraction in orthodontic treatment may affect the vermilion upper lip thickness and facial axis, but that this does not have any negative effects on the soft-tissue facial profile. Premolar tooth extraction can be performed by establishing an accurate diagnosis and treatment plan to avoid undesirable and negative effects on the facial soft-tissue profile.

Treatment of facial asymmetry and severe midline deviation with orthodontic mini-implants

This case report describes the treatment of a 29-year-old woman with facial asymmetry and 2 hopeless teeth. Her lower dental midline was shifted to the left side, and the mandibular left second molar would need to be extracted because of severe caries. The maxillary right second premolar was root rest, and the upper dental midline was shifted to the right side. Because of the patient's asymmetry and Class III skeletal pattern, a severe Class III relationship in the right canine region and lingual crossbite in the left side was observed. She did not want jaw surgery. The mandibular right first premolar, 2 hopeless teeth, and maxillary left second premolar were extracted, and orthodontic mini-implants were used to correct the dental midline, crossbite, and crowding. The mandibular left third molar was moved to the second molar extraction space by using orthodontic mini-implant anchorage. Adequate functional and esthetic results were obtained. Correction of the crossbite on the left side could improve facial asymmetry by changing the drape of the overlying lips.

Three-dimensional soft tissue changes in orthodontic extraction and non-extraction patients: A prospective study

OBJECTIVES

To assess the soft tissue changes in orthodontic extraction and non-extraction patients on 3D stereophotogrammetric images.

SETTING AND SAMPLE

23 extraction (22.2 ± 9.2 years) and 23 non-extraction (20.3 ± 11.1 years) consecutive patients were enrolled at the Sections of Orthodontics at Aarhus University and at University of Naples Federico II.

METHODS

All patients had a first 3D image taken after bonding of brackets on the upper incisors (T0), and a second 3D image (T1) after space closure in the extraction group or at insertion of the first SS or TMA rectangular wire in the non-extraction group. The 3D images were captured with 3dMDFace System and analysed with 3dMDVultus Software. After placing 19 landmarks, 15 measurements were obtained. Intragroup changes were analysed with paired t-test and intergroup changes with unpaired t-test (P < .05).

RESULTS

Superimpositions of the 3D images at T0 and T1 visualized with colour-coded maps showed that soft tissue changes primarily happened in the perioral area in both groups. The Nasolabial angle increased significantly in the extraction group (3°± 4.1, P = .002), while it decreased in the non-extraction group (-1.5°± 5.5°, P = .002). There was a significant difference between the two groups (4.4°, P = .004).

CONCLUSIONS

3D comparison of the soft tissues in the extraction and non-extraction groups showed statistically significant, but clinically limited differences in the perioral area. The Nasolabial angle was significantly larger at T1 in the extraction group compared with the non-extraction group.

Lip repositioning surgery for gummy smile: 6-month clinical and radiographic lip dimensional changes

OBJECTIVES

The present case series aimed to examine lip repositioning surgery (LRS) outcomes related to changes in external and internal upper lip (UL) dimensions, utilizing both conventional clinical and novel radiographic approaches.

MATERIALS AND METHODS

Patients (n = 13) diagnosed with hypermobile UL (>8-mm mobility during smile) and excessive gingival display (≥4-mm) were included and assessed at baseline and 6 months postoperatively. Clinical parameters at rest included total lip and internal lip length (vestibular depth). At maximum smile included total lip, philtrum (ergotrid), and vermilion lengths. Cephalometric parameters included anterior maxillary height; lip length; nasolabial angle; anteroposterior lip thickness; internal lip length (vestibular depth); and vestibular fornix position (using novel approach employing radiopaque marker). Linear mixed-effect models, Pearson's correlation, and linear regression were used for statistical analyses.

RESULTS

LRS did not affect total UL length at rest (p = 0.418). It resulted in significant internal UL length decrease (-3.8 ± 2.1 mm, p < 0.001) and significant increases of vermilion length (1.9 ± 1.0 mm, p < 0.001) and anteroposterior lip thickness (0.7 ± 0.7 mm, p = 0.002). The clinical and radiographic measurements of total UL length at rest (r ≥ 0.734) and of internal UL length (r ≥ 0.737), and the two radiographic assessments of vestibular depth (r = 0.842), were strongly correlated.

CONCLUSIONS

LRS resulted in significant decrease of vestibular depth/internal UL length and in significant increases of UL vertical vermilion length and UL anteroposterior thickness, without affecting total UL length at rest.

CLINICAL RELEVANCE

The documented lip dimensional outcomes should help practitioners when treatment-planning LRS and counseling patients seeking treatment for hypermobile UL.

Measurement of three-dimensional changes in lip vermilion in adult female patients after orthodontic extraction: a retrospective longitudinal study

BACKGROUND

3D facial scanning has changed the way facial aesthetic is evaluated and has numerous advantages for facial analysis. The specific relationship between lip vermilion morphological changes after orthodontic extraction treatment has not been fully explained. The objective of this study was to evaluate 3D morphological changes after orthodontic extraction treatment in lip vermilion of adult females with dentoalveolar protrusion using a structured light-based scanner.

METHODS

Forty-two female subjects (25.2 ± 1.9 years) were recruited as the treatment group; these patients had undergone extraction treatment and achieved better sagittal profiles. Twenty female subjects (25.5 ± 2.1 years) were enrolled in the non-treatment group; these patients did not require any orthodontic treatment. The follow up time for the treatment group was more than 24 months and for the non-treatment group was more than 12 months. 3D facial scans were captured using 3D CaMega. Six landmarks (Ls, Li, R.Chp, L.Chp, R.Ch, and L.Ch), three linear measurements (mouth height, philtrum width, and mouth width), and three area measurements (upper, lower, and total vermilion area) were measured. The spatial deviations of three volumetric measurements (upper, lower, and total vermilion) were constructed for quantitative analysis. Color-coded displacement map were constructed for visualization of the soft-tissue displacement as qualitative evaluation.

RESULTS

Mouth height and philtrum width decreased (-0.93 mm and - 1.08 mm, respectively) significantly (p = 0.008 and p = 0.027, respectively), and no significant (p = 0.488) change in mouth width was observed in the treatment group. The lower and total vermilion surface areas decreased (-51.00mm2 and - 69.82mm2, respectively) significantly (p = 0.003 and p = 0.031, respectively) in the treatment group, but no statistically significant (p = 0.752) change was detected in the upper vermilion. In the treatment group, significant retractions were observed in the color-coded displacement map, and three volumetric measurements of vermilion changed significantly (p = 0.012, p = 0.001 and p = 0.004, respectively). Significant differences were found between the treatment group and the non-treatment group in the linear, area and volumetric measurements.

CONCLUSIONS

This study established a method for qualitative and quantitative evaluation of the lip vermilion. Significant 3D retraction of the lip vermilion after the extraction treatment was found, with morphological variation between upper and lower vermilion.

Analysis of correlation of 3-dimensional lip vermilion morphology and dentoskeletal forms in young Chinese adults on the basis of sex and skeletal patterns

INTRODUCTION

The objective of this research was to evaluate the correlation between 3-dimensional (3D) lip vermilion (LV) morphology and skeletal patterns as well as incisor measurements in young Chinese adults.

METHODS

In all, 240 young adults were enrolled; these included 80 patients each with skeletal Class I, Class II, and Class III malocclusions, respectively. Each sagittal skeletal pattern included 40 male and 40 female subjects. Twenty-two 3D LV measurements were obtained from 3D facial scans. Skeletal and incisor measurements were evaluated on lateral cephalograms. Correlation and regression analysis were performed between soft and hard tissue measurements.

RESULTS

Six of 22 LV measurements showed significant differences between male and female subjects. The 3D LV morphology showed significant differences with respect to different skeletal patterns and sex. Adults with skeletal Class III malocclusion tended to have thinner upper vermilion and fuller lower vermilion than subjects with skeletal Class II and III malocclusion. The mandibular plane angle negatively correlated with the upper-lower vermilion midsagittal curve length and surface area ratio in adults with skeletal Class I and II malocclusion, yet the vertical facial skeletal type showed no correlation in adults with skeletal Class III malocclusion. The vermilion angle, central bow angle, vermilion height, vermilion midsagittal curve length, vermilion height and width ratio, and vermilion surface area showed a significant correlation with incisor measurements. Regression analysis found that the ANB angle was an important factor affecting the upper and lower vermilion midsagittal curve length and surface area ratio. Further, the vermilion height and height and width ratio were closely correlated with the interincisal (U1/L1) angle, whereas the central bow angle was closely correlated with the maxillary incisor torque.

CONCLUSIONS

Most LV morphology variables were correlated to skeletal patterns and incisor measurements. Skeletal Class III malocclusion showed significant differences in vermilion morphology. Both the sagittal and vertical skeletal pattern have effects on vermilion proportion. The incisor torque was closely correlated to vermilion shape and central bow angle and might influence the vermilion esthetics. However, the proportion of the upper and lower vermilion was mainly affected by the ANB angle.

Unilateral Cleft Lip Repair Using the Chang Gung Technique: An Outcome Analysis

OBJECTIVE

This retrospective study analyzed the outcomes of patients undergoing complete or incomplete unilateral cleft lip repair using the Chang Gung technique. The goal was to compare the symmetry and change of the technique through the measurement of anthropometric points on digital photographs.

METHODS

From 2010 to 2016, a total of 274 complete and incomplete cleft lip patients without other craniofacial deformities were included in the study. All included patients had a minimum 1-year follow-up with frontal view photographs taken. The vermilion area, lip width, vermilion height, lateral lip length, lip height, and Cupid's bow width of both cleft and noncleft sides were measured for all patients. The Cleft Lip Component Symmetry Index was used to determine the symmetry of the cleft and noncleft sides in both incomplete and complete cleft groups.

RESULTS

A total of 152 complete and 122 incomplete cleft lip patients were included in the study. The mean Cleft Lip Component Symmetry Index values showed that the vermilion area, lip height, and Cupid's bow width were symmetric on both cleft and noncleft sides. Lip width and lateral lip length were noted to be shorter, whereas the vermilion height was thicker on the cleft side than on the noncleft side. Significant differences between the complete and incomplete cleft group measurements were found for lateral lip length and lip height, and complete cleft measurements were shorter than those for incomplete clefts. There were no significant differences in vermilion area, lip width, vermilion height, and Cupid's bow width.

CONCLUSIONS

The outcome analysis showed that vermilion height reduction and modifications could be made for both complete and incomplete groups. The complete cleft lip has been found to have a significantly shorter lateral lip length and lip height, reflecting a more severe anatomical soft tissue deficiency in this group. A long-term outcome anthropometric point study may further verify the results of this surgical technique.

Three-dimensional assessment of nasal changes after maxillary advancement with impaction using stereophotogrammetry

OBJECTIVE

To evaluate the changes in the nose in three dimensions after Le Fort I osteotomy in patients with skeletal Class III malocclusion.

METHODS

The subjects were 40 adult patients (20 females and 20 males; mean age, 20.3 ± 3.0 years; range, 17.0 to 31.1 years) who underwent one-piece Le Fort I osteotomy with maxillary advancement and impaction treatment for maxillary hypoplasia. The mean maxillary advancement was 4.56 ± 1.34 mm, and the mean maxillary impaction was 2.03 ± 1.04 mm. Stereophotogrammetry was used to acquire three-dimensional images before and at least 6 months after surgery.

RESULTS

Alare (Al) and alare curvature (Ac) points had moved vertically and anterolaterally postoperatively. A significant increase was observed in the nasal ala width and alar base width, and no changes were noted in the columellar length, nasolabial angle, and nasal area. There was a significant relationship between maxillary impaction and nasal ala width and horizontal and sagittal positions of the bilateral Al and Ac. The only relationship found was between maxillary advancement and postoperative sagittal location of the subnasale and pronasale.

CONCLUSIONS

Nasal soft tissues were highly affected by the vertical movement of the maxilla; however, the soft tissue responses were individual-dependent.