Soft tissue cephalometric analysis: diagnosis and treatment planning of dentofacial deformity

The Application of the Divine Proportion for the Construction of the Visualized Treatment Objective in Craniofacial Surgery

ABSTRACT

Aesthetics and function of maxillofacial district are closely related and could interfere with patient psychological conditions. The aim of this paper is to describe and to analyze the procedures necessary for a proper surgical visualized treatment objective (VTO) realization through the use of the tracing on lateral head film, applying the divine proportion (or golden ratio) in certain steps. The method described is easy to realize, cheap and help both orthodontist and maxillo-facial surgeon to communicate each other and to the patients.For the following article, digital research and handheld research on surgical VTO planning for patients with skeletal or dentoalveolar severe deformities managed by surgeons and orthodontics were used. The research included articles in English published on dental and maxillofacial surgery journals.The surgical VTO consists of a "previsualization" of the objectives in order to make the desired changes for the individual patient. The result can thus be visualized and pre-evaluated rather than just imagined by the mind's eye. To simplify the procedure, the surgical VTO has been divided into 11 steps. The accurate model of the surgical result is fundamental in the treatment of dentofacial deformities. These predictions are intended to guide the treatment towards the desired result, to give the patient a reasonable preview of the outcome, and to ensure communication between the orthodontist and the surgeon.This technique proves to be effective in planning surgical treatment and it allows the clinician to view changes before, during, and after orthognathic surgery. The skeletal, dental, and aesthetic complete cephalometric evaluation is the key point to the long-term success of the results.

Is the Temporomandibular Joints' Reciprocal Clicking Related to the Morphology and Position of the Mandible, as Well as to the Sagittal Position of Lower Incisors?-A Case-Control Study

The number of patients diagnosed with temporomandibular joint (TMJ) internal derangements, who are seeking orthodontic treatment, is increasing. The aim of the study was to assess the relationship between the presence of TMJ reciprocal clicking and the morphology and position of the mandible, and position of lower incisors, examined on the lateral cephalograms. Fifty patients diagnosed with reciprocal clicking in at least one of the TMJs and 55 patients with no symptoms of TMJ dysfunction were included in the study. Cephalometric analysis was used for the assessment of: skeletal class, sagittal and vertical position of the mandible, angle of the mandible, inclination of the mandibular ramus and the mandibular corpus, as well as for the assessment of the position of the mandibular incisors. The statistical significance level was set at p = 0.05. There were no statistically significant differences between the examined groups regarding the sagittal and vertical position of the mandible, as well as regarding the sagittal position of the mandibular incisors. Presence of TMJ reciprocal clicking is not associated with the position and the morphology of the mandible, as well as with the sagittal position of the mandibular incisors. Patients with early stages of TMJ internal derangements do not present any significant changes in Cephalometrics. Patients diagnosed with TMJ internal derangements before orthodontic treatment require an interdisciplinary approach to the treatment, including physiotherapy.

Nasal Morphology and Its Correlation to Craniofacial Morphology in Lateral Cephalometric Analysis

Nose shape, size, and inclination influence facial appearance, but few studies concern the relationship between the nasal profile and craniofacial structures. The objective of this study was to analyze association of nasal cephalometric variables with skeletal structures, age, and sex. Cephalometric and nasal analysis was performed in 386 Polish orthodontic patients (aged 9-25 years). Student t-test and Mann-Whitney test were used to compare quantitative variables and Pearson's or Spearman's correlation coefficients-to find correlations. Soft tissue facial convexity angle correlates to Holdaway ratio, ANB (A-Nasion-B), and Wits appraisal. Nasal dorsum axis, nose length, nose depth (1) and nose depth (2), nose hump, lower dorsum convexity, and columella convexity increase with age. Nasal base angle, nasolabial angle, nasomental angle, soft tissue facial convexity and nasal bone angle decrease with age. Nasal base angle and nasomental angle are smaller in females. Thus, a relationship exists between nasal morphology and sagittal jaw configuration. Nasal parameters significantly change with age. Sexual dimorphism characterizes nasal bone angle and nasomental angle.

Methods of Analysis of the Nasal Profile: A Systematic Review with Meta-analysis

The nose is the most prominent structure of the face, influencing facial appearance and profile. Orthodontists have an awareness of facial structures, including nasal morphology, when diagnosing and treatment planning. Maxillofacial surgeons influence facial profile by bimaxillary surgery, improving facial aesthetics and harmony. The aim of this review was to summarize the available methods of analysing nasal morphology and profile, and to assess their complexity. A literature search was conducted in PubMed, Scopus, Web of Science, and Embase using the following search terms: "nasal profile analysis", "nasolabial angle", and "nasal profile cephalometric" in order to select studies providing knowledge on correlations between occlusion and nasal development, differences between skeletal classes, ethnic variability, and differences between the sexes. Studies concerning genetic disorders were excluded. Finally, 17 full-text papers were analysed, which pertained to nasolabial angle, or facial profile including the nose. Data concerning methods, ethnic group, reference landmarks used, and measurements made were extracted and placed in tables. Numerous methods of nasal profile analysis can be found in the literature. These methods describe various numbers of parameters, which have influence on facial aesthetic. Nasal parameters are correlated to skeletal class and nasolabial angle, positions of upper incisors, and maxillary inclination.

Sagittal Relationship between the Maxillary Central Incisors and the Forehead in Digital Twins of Korean Adult Females

OBJECTIVE

Digital twins of adult Korean females were created as a tool to evaluate and compare the sagittal relationship between the maxillary central incisors and the forehead before and after orthodontic treatment.

METHODS

Digital twins were reconstructed for a total of 50 adult female patients using facial scans and cone-beam computed tomography (CBCT) images. The anteroposterior position of the maxillary central incisor and the forehead inclination were measured.

RESULTS

The control group presented a mean of 6.7 mm for the sagittal position and 17.5° for forehead inclination. The study group showed a mean of 9.3 mm for the sagittal position and 13.6° for forehead inclination. Most Korean females seeking orthodontic treatment had their maxillary central incisor anterior to the glabella. In contrast, fewer Korean females who completed their orthodontic treatments had their maxillary central incisor anterior to the glabella. Furthermore, patients who had completed the orthodontic treatment were more likely to have the maxillary central incisor between the forehead facial axis and glabella.

CONCLUSION

The use of digital twins for three-dimensional (3D) analysis of the profile implies a high clinical significance. In addition, as the facial profile of Koreans is different from that of Caucasians, careful consideration should be made when setting treatment goals for the anteroposterior position of the maxillary central incisors.

Severe skeletal bimaxillary protrusion treated with micro-implants and a self-made four-curvature torquing auxiliary: A case report

BACKGROUND

Bimaxillary protrusion is a clinically common dentofacial deformity, particularly among Chinese patients. This kind of malformation can severely affect facial esthetics and, even in mild cases, is difficult to correct without surgery. Unfortunately, many patients abandon treatment because of fear of surgery. Here, we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments, highlighting an alternative treatment option.

CASE SUMMARY

A 31-year-old woman wished to address a severe protrusion profile (approximately 8 mm overbite) and gummy smile. Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion, and proclined and protrusive mandibular incisors. Panoramic radiograph showed a missing mandibular right third molar. A diagnosis of severe bimaxillary dentoalveolar protrusion was made. Taking into account the patient’s fear of orthognathic surgery, she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary. The treatment allowed for maximal en masse anterior tooth retraction, proper relocation of incisors, and alleviation of the skeletal class II pattern. Esthetically, the patient’s lip protrusion was significantly decreased as was the overjet (from 10.5 mm to 1.8 mm), and the results remained stable throughout the 2-year follow-up.

CONCLUSION

Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults.

A one-arm surgical trial of obstructive sleep apnea (OSA) patients before and 12 months after Bilateral Internal Ramus Distraction of the mandible (BIRD)

BACKGROUND

An innovative approach for the primary and definitive treatment of obstructive sleep apnea (OSA) in adult patients is presented: Bilateral Internal Ramus Distraction of the mandible (BIRD), which is a slow, progressive and more stable procedure to advance the mandibular bone. This study investigated whether this surgical approach is useful to cure OSA.

METHODS

Study design was of an interventional (surgical) one-arm trial of OSA patients assessed before and 12 months after BIRD. All patients were evaluated by pre- and post-operative polysomnography and three-dimensional scans. The amount of skeletal advancement, percentage of upper airway volume increase and postoperative value of mandibular occlusal plane were the predictor variables. Changes in the apnoea-hypopnoea index (AHI), oxygen desaturation index (ODI), and percentage of time with saturation under 90% (TC90) were the main outcome variables.

FINDINGS

Thirty-two subjects with a mean ± SD age of 41.9 ± 13.3 years and 87.5% male were included, and they were followed-up 32 ± 14.2 months. AHI was 47.9 ± 23.1 per hour before surgery and the Epworth Sleepiness Scale (ESS) was 13.4 ± 4.4. Postoperative AHI was 4.8 ± 5.6 per hour 12 months after surgery (P < 0.001), with 81.2% of the patients considered cured (AHI<5) and 18.8% suffering from a mild-to-moderate residual OSA. ESS decreased to 1.9 ± 1.8 at the end of the surgical treatment (P < 0.001). 3D changes revealed an upper airway volume increase of 188.4% ± 73.5% (P < 0.001).

INTERPRETATION

Lengthening the mandibular ramus by distraction osteogenesis to cure OSA appears to be more effective and safer when compared to other surgical protocols, especially in very severe cases with initial AHI>50/h. Titration of the mandibular advancement weekly using respiratory polygraphy allows better healing control and customization of the skeletal advancement, enhancing the aesthetic result.

Surgical Orthodontic Treatment in Case of Severe High Angle Skeletal Class II Malocclusion and Mandibular Retrusion

This report describes a patient with severe high angle class II malocclusion and mandibular retrusion in whom surgical orthodontic treatment to prevent an increase in ramus height resulted in a significant improvement in esthetics and long-term stability. The patient was a woman aged 30 years 5 months who presented with the chief complaint of maxillary protrusion. She had a convex facial type, a chin button on lip sealing, and a gummy smile. Cephalometric analysis revealed a normal maxilla anterior-posterior position, but significant mandibular retrusion with pronounced clockwise rotation. The anterior maxillary tooth axis was standard, but labially inclined in the mandible. Based on these findings, the diagnosis was skeletal class II high angle malocclusion and mandibular retrusion. The proposed treatment plan comprised 2-jaw surgery with premolar extraction. Le Fort I osteotomy, in particular, was planned in the maxilla to move the ANS upward by 3.0 mm and the PNS downward by 3.0 mm. Sagittal split ramus osteotomy (SSRO) was planned to adjust the mandible and move the mandible forward by 10.0 mm. To prevent postoperative relapse, the short lingual split method was used in performing the SSRO. The mandible was split to minimize stretching of the median pterygoid muscle. Postoperatively, the ANS, PNS, and pogonion showed movement of 2.0 mm upward, 3.0 mm downward, and 8.0 mm forward, respectively. Additionally, lip closure was now natural, and the gummy smile had markedly improved. At 6 years postoperatively, there has been no change skeletally or dentally. Follow-up is being continued to monitor further progress.

Orthosurgical Management of a Patient with Cleft Lip and Palate

A 31-year-old male patient reported with a chief complaint of a forwardly placed lower jaw. Oral examination revealed Angle's Class III relationship bilaterally and cephalometrically; the patient presented with a small-sized retrognathic maxilla and normal mandible. Orthosurgical treatment was carried out with 4 mm of maxillary advancement and 4 mm of mandibular setback to achieve ideal overjet, overbite, and intercuspation of teeth. The ANB angle showed a drastic change from −9.5° to 1° and a successful conversion of the skeletal profile from Class III to Class I. Orthosurgical treatment can thus be an effective means of treating a patient with cleft lip and palate but requires a detailed understanding of the case and a sound diagnosis to attain a successful outcome.

Comparison of facial esthetic standards between Latin American and Asian populations using 3D stereophotogrammetric analysis

OBJECTIVE

The aim of this study was to compare the facial esthetic standards between Paraguayan and Korean beauty pageant contestants as well as to evaluate the deviation in Farkas proportion indexes (PI) from the golden ratio for each group using three-dimensional (3D) stereophotogrammetric analysis.

METHODS

3D soft tissue images of 34 Miss Paraguay (MP) and 54 Miss Korea (MK) pageant contestants were obtained. The 3D images were digitized and 52 measurements and ratios were calculated. One-way multivariate analysis of variance was applied to compare the two groups. One-sample t-test was applied to assess the differences between the PI of each group and the golden ratio.

RESULTS

The MP group showed greater mouth width, total vermilion perimeter, and lower lip protrusion (P < 0.001) than the MK group. Meanwhile, the MK group showed longer forehead height and total facial height (P = 0.002 and P < 0.001, respectively). All Farkas PIs in each group showed significant differences from the golden ratio except for PI19 (upper/lower vermilion heights).

CONCLUSIONS

Paraguayans favor rectangular faces with wide mouths and large lips, especially the lower lips, whereas Koreans prefer long tapered faces with small mouths and lips. All proportion indexes were significantly different from the golden ratio except for PI19. Therefore, it would be beneficial for clinicians to consider the differences in ethnic preferences in facial esthetics during diagnosis and treatment planning.

The Prediction Capacity 3-D Software, on a 2-D Analysis, in Planning the Positioning of the Upper Lip After Maxillary Advancement

Purpose

The maxillary advancement using Le Fort I osteotomy directly affects in the positioning of the upper lip (UL) and the nasolabial angle (NLA), which plays an important role in facial expression and aesthetics, because of this, the aim of this study was to evaluate the ability of Dolphin Imaging 11.8 software in predicting changes to the UL position and NLA in patients undergoing maxillary advancement.

Materials and Methods

It was a retrospective cohort study. Predictive and final tracings using pre- and postoperative Cone beam computed tomography (CBCT) of 24 patients undergoing maxillary advancement, regardless of mandibular movement, were compared. Whether the amount of advancement changes this predictability was also analyzed. The predictive and the 12-month postoperative data were evaluated using Dolphin Imaging 11.8 software and compared. Student t test was used to get the results.

Results

The vertical analysis of the incisal tip and cementoenamel junction of the upper central incisor (UCI) and of the UL were statistically significant (P = .001 for all). The horizontal measurements of the same variables (P = .238, P = .516, P = .930, respectively) and the NLA (P = .060) showed no statistical significance. The amount of advancement did not interfere with the variables analyzed, except for the exposure (P = .009) and inclination of the UCI (P = .010).

Conclusion

It was concluded that the amount of maxillary advancement does not interfere with the UL prediction; the prediction capacity of the software was good for the horizontal measurements, but had a significant error index for vertical measurements.

A Comparison of 3D Facial Features in a Population from Zimbabwe and United States

OBJECTIVES

 The purpose of this study was to determine the differences in three-dimensional (3D) facial features in a population from Zimbabwe and the United States. In addition, this study seeks to establish an average facial template of each population allowing clinicians to treat patients according to their cultural esthetic perceptions.

MATERIALS AND METHODS

 Three hundred one subjects from Zimbabwe and the United States were carefully selected and recruited for the study. Each subject presented with a normal facial profile, no asymmetries, and normal body mass index. The 3D images were captured using the 3dMD cameras. All images were further separated into male and female groups of the respective populations and imported to a dedicated software for analysis.

STATISTICAL ANALYSIS

 The 3D facial images were constructed using Rapidform 6 software to recreate a composite facial average for each group representing a male and female average 3D face of Zimbabwean (Zim) and United States origin.

RESULTS

 The linear measurements showed that the maximum average distance between the Zim-M and Zim-F was 1.24 mm and the minimum distance between the African American (AA)-M and AA-F was 0.24 mm. This was the absolute distance. When the signed linear measurements were taken into consideration, the maximum average distance between Zim-F and AA-M was 1.22 mm and the least average distance between the Zim-M and AA-M was 0.22 mm. The absolute color histograms showed greatest similarity between the Zim-M and AA-M at 58% and the Zim-F had a 25 and 27% similarity with the AA-F and Zim-M, respectively.

CONCLUSION

 The Zim-F showed the most variable features with a broader face, prominent forehead, and retruded alar base compared with their male counterparts and the Zim-M showed a wider prominent malar/zygomatic region, and prominent lateral supraorbital regions. There was a high similarity of 58% between the Zim-M and the AA-M, with the Zim-M showing a more protrusive superciliary arches, and a lateral zygomatic region tapering to the root of the nose.

Selected Orthodontic Principles for Management of Cranio-Maxillofacial Deformities

An understanding of fundamental orthodontic principles involving diagnosis, treatment planning, and clinical strategies is essential for achieving successful outcomes in the treatment of craniofacial patients, particularly cleft lip/palate. This article focuses on: customizing a mandibular dental arch form using the WALA ridge; accurately diagnosing the maxillary skeletal transverse dimension (cusp to cusp/fossa to fossa); coordinating the upper dental arch with the lower; using a smiling profile and glabella vertical to assess anteroposterior jaw position; and leveling the mandibular curve of Spee while considering the lower one-third of the face. These concepts influence treatment outcomes to the extent they are used.

Current status of surgery-first approach (part III): the use of 3D technology and the implication in obstructive sleep apnea

Considering psychosocial needs of patients, it is not surprising that surgery-first approach (SFA) is becoming more popular than ever. Although the concept of SFA was introduced a few decades ago, the limitation of analysis method based on two-dimensional images makes surgeons reluctant to choose SFA. Recently, the advancement of three-dimensional technology allows us to perform SFA even without minimal pre-surgical orthodontic treatment, and the prediction of surgical outcome became more accurate, especially in obstructive sleep apnea (OSA) patients to whom the advantages of SFA should be more significant. Here, we describe the current trend of SFA and its implication in OSA patients.

Three-dimensional cephalometric analysis of the maxilla: Analysis of new landmarks

INTRODUCTION

Clinical evaluation of the midface including the paranasal and upper lip regions is highly subjective and complex. Traditional and 3-dimensional cephalometrics were not developed with the clinical appearance of these midfacial areas in mind and are therefore inappropriate surrogates for the clinical appearance of the midface, making them unsuitable as aids in diagnosing dentofacial deformities. The aim of this study was to evaluate traditional as well as newly defined landmarks and measurements and their correlation with clinical appearance of the midface.

METHODS

Fifty-two subjects who underwent full-field cone-beam computed tomography were recruited for this study. A single examiner assessed each subject's midfacial region (paranasal and upper lip), and a second examiner obtained traditional and newly defined cephalometric measurements for each subject. Both examiners were blinded to each other's data throughout the study. Statistical analysis was performed to assess the correlations of the traditional and novel cephalometric measurements with clinical midfacial findings. The impact of the soft tissue thickness in the paranasal region was also analyzed. The performance of any classification derived from statistically significant variables was analyzed with the use of micro-F scores and area under the receiver operating characteristic curve (AUC).

RESULTS

Both traditional (SNA) and newly defined measurements (SN_ANS, SN_PR, SN_NP, SN_h) had no statistically significant correlation with clinical paranasal diagnosis. However, in the absence of upper lip procumbency or protrusion, SN_NP and SN_h had statistically significant correlations with clinical paranasal diagnosis (P = 0.047 and P = 0.003, respectively). For upper lip analysis, both traditional (SNA) and newly defined measurements (SN_CEJ) had strong correlations with clinical upper lip diagnosis (P < 0.001). All statistically significant cephalometric variables had good intra- and interobserver reliability (correlation coefficients ≥0.972 and ≥ 0.968, respectively) except SNA, which had a low interobserver reliability (correlation coefficient 0.739). Fitted models for paranasal and upper lip analyses showed low micro-F scores, indicating low precision and recall. However, AUC values of 0.7019 and 0.6362 for the paranasal and upper lip analysis, respectively, suggest improved performance of the model when properly trained with a larger sample size.

CONCLUSIONS

Newly defined measurements SN_h and SN_NP correlated with clinical paranasal diagnosis only in the absence of upper lip procumbency and protrusion. SNA and SN_CEJ were strongly correlated with clinical upper lip diagnosis. However, fitted models based on this study sample yielded low micro-F scores, making the fitted models currently unsuitable for anything besides correlation with clinical findings. A larger sample size will be necessary to further clarify the potential roles of these measurements, especially given the reasonable AUC values. The findings of this study demonstrate the highly subjective and relative nature of midfacial diagnosis and the importance of clinical judgment despite the potential utility of some traditional and new measurements.

Non-extraction and multiloop edgewise technique versus orthognathic surgery and fixed appliance in adult class II patients: a cephalometric comparative study

BACKGROUND

An alternative approach to surgery for treating class II adult borderline patients is the non-extraction and multiloop edgewise archwire (MEAW) technique. The aim of the present study is to compare dentoskeletal effects of the orthognathic surgery with the MEAW technique.

METHODS

Thirteen adults (ten women, three men; mean age, 27.8 years) were consecutively treated using the MEAW approach. The control group was made of 13 adults (nine women, four men; mean age, 26.2 years) treated by orthognathic surgery and the multibracket appliance before and after surgery. Lateral headfilms before and after all the treatments were traced for linear and angular measurements, and data were blindly analyzed. ANOVA was conducted to compare any difference over time between the two treatments. Differences over time for each variable, separately for surgery and MEAW, were assessed by Wilcoxon test.

RESULTS

No significant differences between the two groups were detected at baseline. Both treatments were effective in correcting dental discrepancies. A significant difference over time between the two treatments was found in several cephalometric measurements.

CONCLUSIONS

Considering the limits of the present sample the following conclusion emerged: in the MEAW group, the malocclusion correction was predominantly dentoalveolar, and a significant profile change was observed. Significant skeletal and occlusal plane changes were obtained with the orthognathic surgery approach.

An average three-dimensional virtual human skull for a template-assisted maxillofacial surgery

INTRODUCTION

Although many advances have been made in three-dimensional virtual planning in maxillofacial surgery, facial harmony is still difficult to achieve and is heavily dependent on the surgeon's experience. The aim of the study is to present a method to build up an average three-dimensional virtual human skull to be used as a reference template for bone repositioning and reconstruction during maxillofacial surgical interventions.

METHODS

A total of 20 patients (10 females and 10 males) were selected for the optimal outcome after orthognathic surgery. Postoperative cone-beam computed tomography scans were collected and processed in order to obtain three-dimensional digital models of each skull. For male and female subgroups, the three-dimensional skull models were registered and an average three-dimensional virtual skull model was computed. Deviation color maps were calculated to show differences between each postoperative skull model in the population and the obtained average three-dimensional skull. A clinical use case of genioplasty treatment assisted by the provided average three-dimensional skull template was presented.

RESULTS

The overall mean deviation from the average three-dimensional skull model was 1.3 ± 0.6 and 1.6 ± 0.5 mm in male and female subgroups, respectively. For both groups, the greatest deviations were at the area of the mandible, while almost no deviation was found at the zygomatic and orbital areas. In the presented use case, the female average three-dimensional skull model was effectively used for guiding surgical planning.

CONCLUSION

The presented method of obtaining an average three-dimensional virtual human skull may offer the interesting perspective of performing an innovative template-assisted maxillofacial surgery.

Cephalometric studies of the mandible, its masticatory muscles and vasculature of growing Göttingen Minipigs-A comparative anatomical study to refine experimental mandibular surgery

Over many decades, the Göttingen Minipig has been used as a large animal model in experimental surgical research of the mandible. Recently several authors have raised concerns over the use of the Göttingen Minipig in this research area, observing problems with post-operative wound healing and loosening implants. To reduce these complications during and after surgery and to improve animal welfare in mandibular surgery research, the present study elucidated how comparable the mandible of minipigs is to that of humans and whether these complications could be caused by specific anatomical characteristics of the minipigs' mandible, its masticatory muscles and associated vasculature. Twenty-two mandibular cephalometric parameters were measured on CT scans of Göttingen Minipigs aged between 12 and 21 months. Ultimately, we compared this data with human data reported in the scientific literature. In addition, image segmentation was used to determine the masticatory muscle morphology and the configuration of the mandibular blood vessels. Compared to data of humans, significant differences in the mandibular anatomy of minipigs were found. Of the 22 parameters measured only four were found to be highly comparable, whilst the others were not. The 3D examinations of the minipigs vasculature showed a very prominent deep facial vein directly medial to the mandibular ramus and potentially interfering with the sectional plane of mandibular distraction osteogenesis. Damage to this vessel could result in inaccessible bleeding. The findings of this study suggest that Göttingen Minipigs are not ideal animal models for experimental mandibular surgery research. Nevertheless if these minipigs are used the authors recommend that radiographic techniques, such as computed tomography, be used in the specific planning procedures for the mandibular surgical experiments. In addition, it is advisable to choose suitable age groups and customize implants based on the mandibular dimensions reported in this study.

[Surgery First : prediction for skeletal objectives through structural analysis. Comparison of Sassouni and Delaire analysis]

INTRODUCTION

The purpose of this study was to compare two structural cephalometric analysis (Delaire and Sassouni) as surgical decision tools. These two analyses do not include dental compensation for skeletal discrepancies and have been proven reliable especially for the Sendai surgery first protocol developed by Sugawara.

MATERIAL AND METHOD

The two analysis were performed on 20 surgical cases and the proposed skeletal modifications were compared in order to measure the differences and see if those differences varied according to the facial type. For 10 cases the Virtual Surgical Planning (VSP) images obtained from Dolphin 11.95 Premium software (based on the presurgical CBCT and facial photographs) allowed a comparison of the two analyses as surgical decision indicators and to the realised surgical procedure. The VSP photographs obtained were graded by two panels: one professional and the other one non professional.

RESULTS

Sassouni's analysis favored more forward movements for the maxilla (ENA +5,45) as well as more vertical modifications (Me 1,595). The facial type did not appear to have a significant effect. The quality of Dolphin VSP prediction was judged rather reliable above average (3.7/6) by the panels. The VSP photographs obtained from the two analyses were presented to the panels as well as the VSP obtained from the actual surgery. The three facial outcomes: Sassouni, Delaire and "Surgery Realised" called Dolphin showed some potentially interesting differences. The small size of the sample did not show any significant findings (t test) but a special analysis revealed a valid difference between the three outcomes. The most aesthetic being Dolphin (surgery realised) 17.4 then Sassouni 16.6 (diff 0.8) and finally Delaire 14 (diff 2.6).

CONCLUSIONS

The two structural analysis Delaire and Sassouni did not give the same surgical objectives. Sassouni favored more forward movements for the maxilla as well as more vertical modifications. The Dolphin software appeared to be the quite reliable software to predict the facial outcomes of the surgery. The VSP photographs obtained using Sassouni's analysis were more balanced than when the Delaire analysis was followed (16.4/14 = +2.6). The VSP based on the actual surgery was judged to be even more aesthetic. This shows that beyond a cephalometric analysis the facial aesthetic details and the functional analysis are very important during the phase of surgical planning.

Anteroposterior and vertical soft tissue cephalometric norms of Iranians, interethnic comparisons, sex dimorphism, and the effect of age on cephalometric variables

INTRODUCTION

This study established about 50 anteroposterior and vertical cephalometric norms of five tracing analyses in Iranians, using a large sample.

METHODS

Lateral cephalographs of 130 subjects (85 females, 45 males, with an average age of 22.77 ± 2.55 years (range 20-29)) were traced manually using the Ricketts, Holdaway, Z-Merrifield, Epker, and Legan-Burstone soft tissue analyses. The role of age and sex on measurements, as well as the comparisons between Iranian norms with Caucasians from European decent, was determined statistically (α = 0.001).

RESULTS

Age had no significant effect (all P values > 0.01). Sexual dimorphism existed in terms of numerous parameters. Compared to analysis standards, upper lip to E-plane, nose prominence, upper lip thickness, nasomental angle, Z angle, interlabial distance, subnasale perp to chin, subnasale-stomion:stomion-menton, subnasale-lower lip:lower lip-menton, interlabial gap, and vertical lip-chin ratio were smaller in Iranians. Superior sulcus depth, skeletal profile convexity, upper lip strain, upper lip curvature, H-angle, soft tissue chin thickness, nasofacial angle, subnasale perp to upper lip, subnasale perp to lower lip, maxillary prognathism, lower face throat angle, upper lip protrusion, lower lip protrusion, mentolabial sulcus, and lower vertical height-depth ratio were greater in Iranians compared to the norm (P ≤ 0.001).

CONCLUSIONS

A great degree of sex dimorphism might exist among Iranians. Many textbook norms might not be the best options for diagnosis or treatment of Iranians.

Skeletal-versus soft-tissue-based cephalometric analyses: is the correlation reproducible?

OBJECTIVES

Dentofacial deformities can be analyzed by skeletal and soft tissue cephalometric analysis (CA). The aim was to evaluate the difference in reproducibility between both methods.

MATERIALS AND METHODS

Lateral cephalograms of 112 patients (65 females and 47 males, 27.7 ± 9.0 years) were oriented in natural head position (NHP) and digitized. The distances of skeletal (SNA, SNB, SnPog) and soft tissue (A', B' and Pog') landmarks relative to the respective norm values and the angles between the Nasion Sella line (NSL) and Frankfurt horizontal (FH) to NHP were measured for statistical evaluation and compared with respective data of an adult control group (CG) with class I occlusion and harmonic facial balance.

RESULTS

The mean differences (mm ± SD) of skeletal and soft tissue landmarks were -2.4 ± 4.4 (A), -7.0 ± 9.3 (B), -6.3 ± 11.2 (Pog), -0.9 ± 1.8 (A'), -4.7 ± 6.2 (B'), and -6.1 ± 7.8 (Pog'), respectively. Pearsons's correlation (r) between the measurements of SNA/A', SNB/B' and SNPog/Pog' were r = .158 (p = .092), r = .662 (p < .001) and r = .655 (p < .001), respectively. The mean (±SD) angles between NSL and FH to NHP were -9.8° ± 5 and 0.0° ± 3.9, respectively.

CONCLUSION

Variability of cranial-based measurements could give a possible explanation for the high variation and the low reproducibility of skeletal cephalometric analysis with soft tissue measurements. Soft-tissue cephalometric analysis would probably improve facial analysis and treatment planning.

Volumetric Analysis of Fat Injection by Computerized Tomography in Orthognathic Surgery: Preliminary Report on a Novel Volumetric Analysis Process for the Quantification of Aesthetic Results

BACKGROUND

Integrated approaches to orthognathic surgery should include accurate volumetric evaluation of the skull and soft tissues. In patients with dentofacial deformities, the most frequent aesthetic deficits are attributable to an underdevelopment of hard and soft tissues. Traditional osteotomic procedures often fail to guarantee a stability of soft tissues over time. For this reason, in selecting a surgical strategy, the surgeon should consider not only traditional osteotomies, but also soft-tissue improving procedures, such as lipofilling. Preoperative surgical planning systems, such as the Virtual surgical planning (VSP) protocol, are based mainly on skeletal movement prediction. Quantitative estimation of soft-tissue modifications is not part of common clinical practice. Most commonly, the evaluation of soft-tissue modifications after orthognathic procedures is instead performed by clinical qualitative means.The purpose of this study was to describe a novel computed tomography (CT)-based volumetric analysis process for the quantification of injected autologous adipose tissue in patients who have undergone simultaneous orthognathic and lipofilling procedures.

METHODS

This was a retrospective review of consecutive patients who underwent combined orthognathic surgery and lipofilling from June 2016 to May 2017 for malocclusion with functional and aesthetic impairments. Preoperative planning included clinical evaluation and virtual osteotomy planning according to the VSP protocol. The volume of fat to be injected was estimated clinically by comparing virtual renderings with preoperative clinical photographs. The surgical technique involved Le Fort I and sagittal split mandibular osteotomies, combined with autologous fat injection in the malar and perioral regions. Postoperative evaluation was performed with a novel imaging process based on CT image segmentation to quantify the exact volume of injected fat. Skeletal stability was also evaluated at 3 months.

RESULTS

Sixteen patients were enrolled in the study, all females, with a mean age of 24.5 years (range, 18-36 years). The mean difference between the fat tissue injected and that quantified postoperatively was 6.01 cm. All patients had clinically satisfactory facial convexity, with complete restoration of the cheekbone contour, at 3 months.

CONCLUSION

This study introduces a novel CT-image based technique to quantitatively assess the contribution of injected fat to the postoperative soft-tissue volume increase after combined orthognathic surgery with autologous lipofilling. In the future, this CT-based volumetric analysis technique could be the gold standard for evaluating facial lipofilling outcomes, and for assessing clinical aesthetic outcomes based on the injected volume of fat.

Improvement in lip appearance (lateral and frontal aspects) following mandibular setback surgery

INTRODUCTION

The post-operative facial profile is critical for patients who undergo orthognathic surgery. The present study investigated the improvement in lip appearance (lateral and frontal aspects) following mandibular setback surgery.

MATERIAL AND METHODS

Thirty-one patients with mandibular prognathism underwent mandibular setback surgery. Lateral and posteroanterior cephalograms were obtained before surgery (T0) and more than 1 year after surgery (T1). The landmarks (soft and hard tissues) and linear distances were compared by statistical analysis.

RESULTS

The lateral cheilion (Ch), point B (B), and pogonion (Pog) were significantly setbackin the horizontal plane: 5.59, 11.49, and 12.35 mm, respectively. In the vertical plane, B and Pog did not move significantly. The Ch moved significantly downward by 3.23 mm on average. The setback ratios of soft tissue/hard tissue, soft tissue of B/B, and soft tissue of Pog/Pog were 0.96. The Ch/Pog ratio was 0.45. The width of the frontal Ch was significantly reduced by 3.17 mm.

CONCLUSIONS

The relationship between the corresponding soft and hard tissues of the chin was approximately 1. The relationship between the lip corner and chin bone was nearly 50%. The width of the lip corner was also significantly reduced.

Diagnostic concordance between skeletal cephalometrics, radiograph-based soft-tissue cephalometrics, and photograph-based soft-tissue cephalometrics

Objective

This study aims to investigate the diagnostic concordance between skeletal cephalometrics and soft-tissue cephalometrics in identifying facial lower third characteristics.

Materials and methods

We compared a skeletal cephalometric analysis (SCA) to a soft-tissue analysis performed on cephalometric radiographs (rSTCA) and to one performed on profile photograph (pSTCA). Ninety-six pre-treatment digital lateral cephalometric radiographs and 96 digital profile photographs were randomly selected for this study (patients' mean age: 18.33, SD: 3.38, age range: 14-29). Inclusion criteria were as follows: no skeletal asymmetry, well-aligned upper and lower dental arches, no history of orthodontic treatment, prosthodontic treatment, facial surgery and trauma, patient's age between 14 and 30 years, high-resolution images, exams taken with natural head position. Kruskas-Wallis and post hoc pairwise comparisons tests were used to find differences among the considered cephalometric methods. The diagnostic performance of the three methods was also assessed using the receiver-operating characteristic (ROC) curve analysis.

Results

Significant differences were found between SCA and rSTCA and between SCA and pSTCA in defining sagittal and vertical facial lower third characteristics (P < 0.05). No differences were found between rSTCA and pSTCA (P > 0.05) for the same facial characteristics. For each parameters investigated, pSTCA showed an area under the curve much closer to the perfect value of 1.00.

Conclusion

Poor diagnostic concordance was found between SCA and rSTCA and between SCA and pSTCA. pSTCA is a reliable method for evaluating the soft-tissue profile characteristics compared to that performed on cephalograms.

Injectable profiloplasty: Forehead, nose, lips, and chin filler treatment

INTRODUCTION

We propose a medical filler treatment algorithm of the profile which includes forehead, nose, and chin and to evaluate profilometric results and complications.

MATERIALS AND METHODS

83 case reviews of associated liquid forehead, nose, and chin plasty performed consecutively from 2014 to 2016. We monitored the horizontal and vertical sagittal stability into two age group: <40 y.o. and >40 y.o. using profilometric Arnett analysis measurements on the F, Gb, Na, Nd, Nt, Sn, ULA, LLA, B, Pg, and Gn soft-tissue points.

RESULTS

The results at both 3 and 6 months were consistent with the normal ranges indicated by Arnett, with a 0.8 mm maximum of defect/excess. Forehead treatment was performed in 51 (61.4%) patient. Patients >40 y.o. always needed a global correction of the forehead profile. We performed nasal treatment in 83 (100%) patient, acute nasolabial angles was the more frequent nasal defect. The lips were injected in 59 patients (71.1) more frequently >40 y.o. In 83 (100%) patients we perform a chin augmentation. The average advancement of the chin was 3 mm.

CONCLUSIONS

The correction of the projection of the forehead, of the profile and shape of the nose, of the lips and chin as well as an overall improvement in face aesthetics and harmony gives a good solution in patients avoiding the need for a surgical intervention, scars and cost of general anesthesia, thus providing the optimum in patient satisfaction.

Surgical Treatment of Posttraumatic Laterognathia: A Case Report and a Literature Review, Focused on the Effects of a Condylar Fracture on the Face

Facial asymmetry, following early childhood condylar trauma, is a common complaint among patients who seek surgical treatment. G.D.M., a 27-year-old male patient, sought professional help to correct his cosmetic flaw, caused by a condylar fracture when he was 8-years-old. After the proper orthodontic treatment, he underwent a double jaw orthognathic surgery and, 9 months later, a second one to correct the remaining asymmetry. Two years after this second procedure, the patient is still under surveillance and has no complaints.

Ready to Use Norms for Arnett Bergman Soft-Tissue Cephalometric Analysis for South Indian Population

CONTEXT

Variability of the soft-tissue drape in humans has complicated the accuracy of evaluating soft tissue profiles in diagnosis and treatment planning.

AIMS

The objective of the present study is to establish soft-tissue cephalometric norms for South Indian population using Arnett Bergman Soft tissue analysis.

SETTINGS AND DESIGN

This study was conducted at the Department of Orthodontics and Dentofacial Orthopaedics.

SUBJECTS AND METHODS

Lateral cephalograms of 60 individuals (30 males and 30 females), age ranging between 18 and 25 years, with orthognathic facial profiles were obtained in natural head position. True vertical line was drawn through subnasale parallel to the vertical reference plane. Measurements were done according to soft-tissue cephalometric analysis.

STATISTICAL ANALYSIS USED

Student's t-test was used to compare the means between two groups.

RESULTS

The results of the study showed significant gender dimorphism, with men having thicker soft-tissue structures, larger vertical dimensions, deep-set midface structures, more upright incisors, and deeper inferior labial sulci than women. When compared with the standard norms, the South Indian population had significantly protruded dentition, thinner soft-tissue drape, shorter vertical face heights, prominent forehead and midface with retusive lower facial thirds and convex profiles as compared to Caucasians.

CONCLUSIONS

Significant gender dimorphism was evident in the local population suggesting the need for separate set of norms for males and females. Distinct ethnic differences were found between Caucasians and the Indian population that were statistically significant, highlighting the importance of defining separate set of norms for ethnic groups. The norms obtained should be used as reference when planning treatment of a specific ethnic group.

Chin remodeling in a patient with bimaxillary protrusion and open bite by using mini-implants for temporary anchorage

Patients with bimaxillary protrusion may have an unattractive profile with a retruded chin contour. Correction of the severely protrusive anterior alveolar bone and teeth combined with a moderate open bite without orthognathic surgery can be challenging. This case report describes the orthodontic treatment of a woman with severe bimaxillary protrusion and a moderate open bite. Excellent chin morphology and facial appearance were obtained with the extraction of 4 first premolars and 4 third molars, and total distalization of both arches with 4 mini-implants, one in each quadrant between the second premolar and the first molar. The total treatment time was 30 months.

Assessment of Gingival Biotype and Keratinized Gingival Width of Maxillary Anterior Region in Individuals with Different Types of Malocclusion

Objective

The aim of the present study is to evaluate the relationship of gingival thickness and width of keratinized gingiva with different malocclusion groups and amount of crowding.

Methods

A total of 181 periodontally healthy subjects were enrolled in the present study. The study participants were divided into three malocclusion groups: Angle Class I, Angle Class II, and Angle Class III. Each group was divided into subgroups according to the amount of dental crowding, namely mild, moderate, and severe. The width of keratinized gingiva was calculated as the distance between mucogingival junction and free gingival margin, whereas gingival thickness was determined by a transgingival probing technique.

Results

Tooth numbers 13 and 23 were observed to have thin gingival biotype. The width of keratinized gingiva for tooth numbers 13 and 23 was narrower in the severe crowding group than in the moderate and mild crowding groups. The relationship of gingival thickness and width of keratinized gingiva with Angle classification was not found to be significant.

Conclusion

Although it is thought that there is a relationship between gingival thickness, width of keratinized gingiva, and Angle classification with regard to malaligned teeth, this cross-sectional evaluation of 181 patients failed to show a significant relationship.

Clinical and Cephalometric Analysis of Facial Soft Tissue

OBJECTIVE

This study aimed to provide average of standard values in planning orthognathic surgery in Asians.

MATERIALS AND METHODS

Thirty-three Asians with well-balanced facial profile, combined with class I occlusion and stabilized condylar head were evaluated using lateral cephalograms.

RESULTS

Facial length (Nasion'-Menton') was 138.8 and 127.0 mm in male and female, respectively. Upper and lower lip length were 24.5 and 49.8 mm for male, and 22.2 and 45.1 mm for female, and maxillary incisor exposure was 2.0 and 4.0 mm in male and female, respectively. Nasolabial angle was 77.7° and 84.1° in male and female, respectively. Alar base, A point', and maxillary incisor were placed posteriorly to true vertical line by 10.6, 1.0, and 8.0 mm for male and 9.0, 0.8, and 6.9 mm for female. The horizontal distance between upper lip anterior and lower lip anterior was 2.1 mm for male and 2.6 mm for female, and the horizontal distance between A point' and B point' was 5.3 mm for male and 3.9 mm for female. Orbital rim' to A-point' was 12.4 and 11.3 mm in male and female, respectively. Pogonion' located posteriorly to glabella' by 2.7 mm for male and anteriorly to glabella' by 3.2 mm for female, and facial angle was 156.7° and 147.0° in male and female, respectively.

CONCLUSIONS

This quantitative analysis of facial profile in Asian will be helpful in evaluation of facial soft tissue and establishment of treatment plans for orthognathic surgery.

Visual attention during the evaluation of facial attractiveness is influenced by facial angles and smile

OBJECTIVE

To examine the changes in visual attention influenced by facial angles and smile during the evaluation of facial attractiveness.

MATERIALS AND METHODS

Thirty-three young adults were asked to rate the overall facial attractiveness (task 1 and 3) or to select the most attractive face (task 2) by looking at multiple panel stimuli consisting of 0°, 15°, 30°, 45°, 60°, and 90° rotated facial photos with or without a smile for three model face photos and a self-photo (self-face). Eye gaze and fixation time (FT) were monitored by the eye-tracking device during the performance. Participants were asked to fill out a subjective questionnaire asking, "Which face was primarily looked at when evaluating facial attractiveness?"

RESULTS

When rating the overall facial attractiveness (task 1) for model faces, FT was highest for the 0° face and lowest for the 90° face regardless of the smile ( P < .01). However, when the most attractive face was to be selected (task 2), the FT of the 0° face decreased, while it significantly increased for the 45° face ( P < .001). When facial attractiveness was evaluated with the simplified panels combined with facial angles and smile (task 3), the FT of the 0° smiling face was the highest ( P < .01). While most participants reported that they looked mainly at the 0° smiling face when rating facial attractiveness, visual attention was broadly distributed within facial angles.

CONCLUSIONS

Laterally rotated faces and presence of a smile highly influence visual attention during the evaluation of facial esthetics.

Analysis of facial soft tissue values and cranial skeletal widths in different body mass index percentile adolescent subjects

OBJECTIVE

The purpose of this study was to analyze facial soft tissue thickness and cranial skeletal transverse widths in adolescent subjects with different body mass index (BMI) percentiles.

METHODS

The 80 subjects were divided into three groups according to BMI percentile: normal-weight, overweight, and obese adolescent subjects. Facial soft tissue linear and cranial skeletal transversal width measurements were performed on lateral and postero-anterior cephalometric radiographs.

RESULTS

Glabella, nasion, pogonion, and gnathion soft tissue thicknesses were significantly different among normal-weight, overweight, and obese subjects (p < 0.05). However, other facial soft tissue thickness parameters were not statistically significantly different among the groups (p > 0.05). Moreover, there were no significant differences in cranial skeletal transversal widths among groups (p > 0.05).

CONCLUSION

Nasion soft tissue thickness was thicker in overweight subjects; whereas, glabella, pogonion and gnathion soft tissue thickness was thicker in obese subjects. All measured cranial skeletal widths were similar in normal-weight, overweight, and obese subjects.

Angular Photogrammetric Soft Tissue Facial Profile Analysis of Bangladeshi Young Adults

Introduction

Angular photogrammetric soft tissue facial profile analysis provides a permanent record for the actual appearance of a person, which would also serve to establish an ideal esthetic treatment goal. The aim of the present study was to evaluate the average angular variables that define the soft tissue facial profile of a Bangladeshi sample.

Materials and Methods

This cross-sectional study was carried out at Department of Orthodontics and Dentofacial Orthopedics of Dhaka Dental College and Hospital, Bangladesh, from July to December 2015. Soft tissue facial profiles of 200 participants (100 males and 100 females) between 18 and 25 years of age, with a dental Class I occlusal relationship and harmonious soft tissue profile, were selected by convenience sampling among students, doctors, and patients of Dhaka Dental College. Standardized photographs of 200 samples were taken in the natural head position. The photographic records were analyzed with the software for Windows, Microsoft Visio 2007, Standard Edition. All data were analyzed through standard methods using Statistical Package for the Statistical Package for Social Science Software (SPSS Version-20, IBM Corp, USA).

Results

The average angular measurements for nasofrontal, total facial angle, facial angle, upper lip angle, projection of lower lip to chin, and mentolabial angle were wider in females. The mean value for nose tip angle, nasolabial angle, nasomental angle, and projection of upper lip to chin angle was higher in males compared to females. Nasofrontal angle (G-N-Nd) (P = 0.000) and mentolabial angle (Li-Sm-Pg) (P = 0.001) showed statistically significant differences. The greatest variability was found for mentolabial angle.

Conclusion

The study of angular photogrammetric soft tissue facial profile analysis of Bangladeshi young adults contributes to the establishment of standardized normal values for the population. This study provides data which can be used in treatment planning by specialists such as orthodontists, prosthodontists, plastic surgeons, and maxillofacial surgeons, who have the capability to change the soft tissue facial features.

Which cephalometric analysis for maxillo-mandibular surgery in patients with obstructive sleep apnoea syndrome?

Maxillo-mandibular advancement MMA is considered an efficacious treatment for patients affected by severe obstructive sleep apnoea syndrome (OSAS). Even though OSAS improvement is the main goal of MMA, excessive maxillo-mandibular protrusion should be avoided to guarantee pleasant postoperative facial aesthetics. In order to attain such a result, the amount of MMA should be planned preoperatively by both aesthetic and cephalometric analyses. Steiner and Delaire cephalometric analyses are commonly used in the preoperative planning of orthognatic surgery for dentofacial deformities, however controversies still exist about the basis and postoperative aesthetic results of such cephalometric analyses in OSAS patients candidate for MMA. Forty-eight patients affected by severe OSAS were submitted to MMA. Pre- and post-operative Steiner and Delaire cephalometric tracings were assessed in each subject. For Steiner analysis, the variation in the SNA and SNB angles was measured, while for Delaire tracings the variation in the C3/FM-CPA and C3/FM-Me angles was assessed. Mean MMA was 6.9 + 3.8 mm for the maxilla and 13.6 + 5 mm for the mandible. After surgery, an improvement of the apnoea-hypopnoea index was recorded (40.47 + 7.64 preoperative vs. 12.56 + 5.78 postoperative). In all patients, both cephalometric analyses showed presurgical bimaxillary retrusion. After surgery, the mean value of Steiner's SNA angle increased from 78.18° to 85.58° (p < 0.001), while mean Delaire's C3/FM-CPA angle increased from 81.19° to 89.71° (p < 0.001). The mean value of Steiner's SNB angle increased from 74.33° to 80.73° (p < 0.001), while Delaire's C3/FM-Me angle increased from 80.10° to 87.29° (p < 0.001). Postoperatively, both the maxilla and mandible were in a more protrusive position (p < 0.001) according to Steiner analysis compared with Delaire tracing. Basing MMA on Delaire cephalometric analysis leads to an increased advancement of the maxillo-mandibular complex than Steiner tracing. The consequences of this aspect on facial aesthetics should be considered during surgical planning and preoperative informed consent in OSAS patients candidate for MMA.

3D dentofacial photogrammetry reference values: a novel approach to orthodontic diagnosis

Background

Orthodontic diagnostic standards generally use the cranial base as a reference and rely on samples selected by orthodontists.

Objective

The purpose of this study was to provide male and female standards for a novel non-radiographic approach for orthodontic diagnosis that utilizes 3D dentofacial photogrammetry using the eyes and natural head orientation as references instead of the cranial base.

Methods

One hundred and eighty females and 200 males between the ages of 18 and 35 years from 2 modeling agencies were orthodontically screened for near ideal occlusion. Subjects that met the inclusion criteria were rated by a sample of 40 lay people for attractiveness on a visual analogue scale. The final sample that had 3D facial and dental imaging included 49 subjects 25 males and 24 females with near ideal occlusion and considered attractive by the public.

Results

Inter and Intra-examiner ICC were greater than 0.8 for both landmarking and indexing. Relative to a coronal plane contacting the pupils (MC), the mean sagittal position of the alar curvature (representing the nasomaxillary complex) was 14.36 ± 3.08 mm in males and 12.4 ± 3.58 mm in females. The sagittal position of soft tissue pogonion relative to the pupils was 14.84 ± 3.63 mm in males and 12.78 ± 5.68 mm in females. The angle between the alar curvature and pogonion relative to the pupils was 9° in males and 10° in females. With the exception of the occlusal plane which was steeper in females, no ratios or angular facial measurements showed a significant gender difference. Relative to MC, males had more proclined upper incisors (20° vs 16°) and more retroclined Lower incisors (27° vs 31°; P > 0.05). A Procrustes ANOVA and permutation test showed that the shapes of males and females are different enough to be considered two distinct populations.

Conclusions

1. When using the proposed method for orthodontic diagnosis, male and female patients should be compared to their respective dentofacial standards. 2. Validation of the proposed method and standards on an orthodontic population is underway to determine the scope its use.

Chin-throat anatomy: Normal relations and changes following orthognathic surgery and growth modification

OBJECTIVES

To determine if a new facial line (T), tangent to the throat, intersects the mandibular border in anterior (ANT) and posterior (POST) parts in proportions varying with facial configuration, and to evaluate the association between chin projection and throat inclination and the potential for the T-line to reflect this association.

MATERIALS AND METHODS

Measurements on profile photographs and cephalograms of 135 adults (aged 18-50 years)-45 each of Class I, II, and III (CI, CII, CIII) malocclusions-included ANT and POST, chin-throat (CTA), and mento-cervical (MCA) angles. Pre- and posttreatment measurements were compared in two subgroups (n = 25 each) of CII and CIII orthognathic surgery patients and in CII, division 1 early-treatment patients (n = 63). Statistics included analysis of variance and t-test for group differences, and Pearson correlation for associations among variables.

RESULTS

ANT was nearly equal to POST in CI (50.99%) and CIII (51.86%) subjects and shorter in CII (36.01%) subjects. CTA and MCA were greater in CII profiles and smaller in CIII profiles. Significant differences (P < .0001) were observed for ANT, POST, CTA, and MCA between Classes I/II and II/III and for MCA between Classes II/III (P = .016). High correlations were noted between ANT and CTA in Classes I (r = -0.83), II (r = -0.73), and III (r = -0.68). In surgically treated patients, posttreatment measurements approached CI values. In the early-treatment group, ANT increased but remained smaller than POST; CTA decreased by nearly 13%.

CONCLUSIONS

Chin-throat relations and chin extension are associated and require routine assessment in terms of diagnosis and treatment outcome. A practical tool to assess chin-throat relationship, the T-line bisects the mandibular body nearly equally in Class I faces.

Combined photographic and ultrasonographic measurement of the ANB angle: a pilot study

OBJECTIVE

This study was performed to evaluate the feasibility of noninvasive measurement of the ANB angle using photographic and ultrasonographic methods.

METHODS

Twenty consecutive orthodontic patients were evaluated. The ANB angle and soft tissue thickness covering the N, A, and B cephalometric points were measured by lateral teleradiography; these measurements were made by two expert operators. The soft tissue thickness covering the N, A, and B cephalometric points was measured by ultrasonography; these measurements were also made by two expert operators. On a 1:1 photographic profile print on which the ultrasonographic points were marked, the ANB ultrasonographic angle was measured. The following comparisons were considered: averaged and single measurements of N, A, and B points by first versus second ultrasonographer; averaged and single ultrasonographic versus radiographic soft tissue thickness covering the N, A, B points; and averaged and single ultrasonographic versus radiographic measurements of ANB angle.

RESULTS

High correlation and concordance of the averaged and single measurements, but no significant difference, was found between the two ultrasonographers. No statistically significant difference was found between the two methods for measuring averaged soft tissue thickness, but a 20% difference was found for the single measurements. High correlation and concordance between the ultrasonographic and radiographic measurements, but no significant difference, was found between the single and averaged ANB angle measurements.

CONCLUSION

Ultrasonography seems to be a noninvasive and reliable technique for measurement of the ANB angle and may replace radiographic measurement in some cases.

Surgery-first: a new approach to orthognathic surgery

This case study describes the treatment of a 20-year-old white woman with a skeletal Class III and dental Class III malocclusion followed by a retrognathic and contracted maxilla, light mandibular crowding and a median line deviation of 5 mm. The treatment was based on the Surgery-First approach, involving LeFort I maxillary advancement surgery, and it was followed by orthodontic treatment. During the 6-month treatment period, excellent aesthetic results and good functional occlusion were achieved.

A safe and accurate method to perform esthetic mandibular contouring surgery for Far Eastern Asians

A tapered mandibular contour is popular with Far Eastern Asians. This study describes a safe and accurate method of using preoperative virtual surgical planning (VSP) and an intraoperative ostectomy guide to maximize the esthetic outcomes of mandibular symmetry and tapering while mitigating injury to the inferior alveolar nerve (IAN). Twelve subjects with chief complaints of a wide and square lower face underwent this protocol from January to June 2015. VSP was used to confirm symmetry and preserve the IAN while maximizing the surgeon's ability to taper the lower face via mandibular inferior border ostectomy. The accuracy of this method was confirmed by superimposition of the perioperative computed tomography scans in all subjects. No subjects complained of prolonged paresthesia after 3 months. A safe and accurate protocol for achieving an esthetic lower face in indicated Far Eastern individuals is described.