Optimizing Botulinum Toxin A Administration for Forehead Wrinkles: Introducing the Lines and Dots (LADs) Technique and a Predictive Dosage Model.

This study introduces the Lines and Dots (LADs) technique, a new approach for administering botulinum toxin type A (BoNT-A) in treating forehead wrinkles. (1) Background: BoNT-A application patterns in the forehead often rely solely on the anatomy of the frontalis muscle. The LADs technique proposes a combination of anatomical features with nerve pathways. (2) Methods: The technique employed a grid system aligned with the supraorbital and supratrochlear nerve pathways and used an electronic acupuncture pen for validation. This study analyzed treatment outcomes for efficacy and safety and proposed a predictive model for BoNT-A dosage. (3) Results: LADs was associated with a high satisfaction rate and low side effect incidence. The predictive model followed BoNT-A Units=0.322×Muscle Pattern Code+1.282×Line Type Code+2.905×Severity Pre-Treatment+3.947. (4) Conclusions: The LADs technique offers an alternative approach to treating forehead wrinkles, optimizing efficacy while minimizing the BoNT-A dose required.

Anatomical Proposal for Botulinum Neurotoxin Injection for Horizontal Forehead Lines.

SUMMARY: The frontalis muscle is situated across the forehead and is a representative target muscle for botulinum neurotoxin (BoNT) injections aimed at treating horizontal wrinkles in this region. However, a lack of anatomical information regarding the shape and thickness of the frontalis may lead to unexpected adverse effects, such as ptosis and samurai eyebrows, caused by the lack of detail on anatomical variation. Achieving the maximum effect using the minimal amount of BoNT requires a precise injection into the frontalis muscle. The anatomical factors associated with BoNT injection into the frontalis muscle have been reviewed in the current study. Up-to-date understanding of the localization of the BoNT injection point according to an updated understanding of the anatomy leads to more accurate localization of the injection point into the frontalis muscle. Optimal injection sites have been provided for the frontalis muscle, and the injection method has been recommended. The authors suggest optimal injection sites according to the external anatomical landmarks of the forehead. Furthermore, these proposals could aid in a more precise procedure that avoids the deleterious effects of BoNT.

Facial Analysis for Gender Affirmation/Gender-Related Facial Analysis.

There are anthropometric differences between the bony and integumentary facial features of male and female individuals. When compared to males, female faces in general are more heart-shaped, with a shorter and smoother forehead, a smaller more defined nose, and a tapered chin.

An Exploration of the Anatomy of the Forehead of Asians and Its Relationship With Forehead Lines Based on Ultrasound Imaging.

BACKGROUND: A profound understanding of the various frontal tissues' morphology and their relationship with forehead lines can efficiently guide clinical treatment. OBJECTIVES: The authors explored the relationship between frontal anatomy and frontal lines. METHODS: We measured the thickness and shape of tissues in different regions of the forehead of 241 Asians. Then, we analyzed the relationship between the types of frontalis muscle and frontal lines, as well as the relationship between the frontal anatomical structures and the production of frontal lines. RESULTS: We classified the types of frontalis muscle into 3 categories comprising 10 subtypes. The skin (0.78 mm vs 0.90 mm, P < .05), superficial subcutaneous tissue (0.66 mm vs 0.75 mm, P < .05), and frontalis muscle thickness (0.29 mm vs 0.37 mm, P < .05) of people with obvious dynamic forehead lines were significantly thicker than those of people without significant dynamic forehead lines. However, no significant difference in the deep subcutaneous tissue thickness was found between people with and without static forehead lines (1.36 mm vs 1.34 mm, P < .05). CONCLUSIONS: This study shows the relationship between the frontal structure and frontal lines. Therefore, these results can provide references for treating frontal lines, to a certain extent.

Sagittal Position of the Upper Incisor in Relation to the Forehead in Peruvian Individuals with Different Skeletal Relationships.

AIM: The aim of this study was to determine the sagittal position of the upper incisor considering Andrews' analysis based on the position of the forehead in Peruvian individuals with different skeletal relationships. MATERIALS AND METHODS: This retrospective, cross-sectional study included 212 lateral head radiographs of Peruvian individuals (males: 85, mean age 21.38 ± 6.88, and females: 127, mean age 21.18 ± 6.95), with different skeletal relationships (Class I group = 96, Class II group = 57, Class III group = 59). The values of the ANB, SNA, SNB angles as well as the forehead anterior limit line (FALL) and goal anterior limit line (GALL) points were identified in the radiographs, and then a vertical line was drawn in each point to determine if the upper incisor was positioned forward (protruded), backward (retruded) or within (adequate) these lines. Two trained and calibrated investigators performed all the measurements. The Chi-square test was used to evaluate associations. A p-value < 0.05 was considered statistically significant. RESULTS: Overall, the sagittal position of the upper incisor showed a significant association with the sagittal skeletal relationship (p = 0.001). The upper incisors showed an adequate position (41.7%), protruded position (56.10%), and retruded position (42.40%), for Class I, II, and III skeletal relationships, respectively, as highest percentages in each Class. Statistical significance was found for females only (p = 0.005). CONCLUSION: Skeletal Class I mainly showed an adequate position of the upper central incisor, whereas for Class II a protruded position was most frequently found, and Class III presented a retruded position. CLINICAL SIGNIFICANCE: Andrews' analysis based on the position of the forehead in Peruvian individuals is a valuable tool for orthodontic diagnosis. How to cite this article: Bazán-Mendoza JR, Arias-Modesto PB, Ruíz-Mora GA, et al. Sagittal Position of the Upper Incisor in Relation to the Forehead in Peruvian Individuals with Different Skeletal Relationships. J Contemp Dent Pract 2023;24(11):821-825.

Subcutaneous Lateral Temporal Lift.

Over the past decades, the understanding of the nuances of forehead anatomy and facial aging has grown immensely. Safe and reliable options for forehead rejuvenation followed. Although noninvasive techniques are an important adjunct in forehead rejuvenation, the mainstay of treatment of the eyebrow is operative intervention. The senior author's technique has developed over many years, first focusing on the open coronal and anterior hairline approach to the forehead lift, then the endoscopic brow lift, and most recently, the lateral subcutaneous temporal lift. This technique allows for reliable and safe elevation of the lateral brow with minimal complications.

Applied anatomy of the layers and soft tissues of the forehead during minimally-invasive aesthetic procedures.

BACKGROUND: An increasing demand of minimally-invasive aesthetic procedures of the forehead concomitantly leads to higher numbers of adverse events. Adequate application of anatomical knowledge is required to increase safety and efficacy of different minimally-invasive aesthetic procedures in this anatomical region. OBJECTIVE: To describe the layered anatomy of the forehead soft tissues with respect to their thicknesses and how they relate to different minimally-invasive aesthetic treatments. METHODS: A total of n = 85 healthy study participants (69 females and 16 males) with a mean age of 40.84 ± 10.9 years and a mean body mass index of 22.65 ± 2.6 kg/m2 were investigated with ultrasound-based imaging to measure the thickness of different forehead soft tissues. RESULTS: The mean overall soft tissue thickness of the forehead was measured to be 4.18 ± 0.7 mm for the entire study population. Increasing BMI values correlated statistically significantly with increasing thickness of all measured forehead soft tissues with exception of the frontalis muscle. On a statistically significant level, males showed thicker forehead soft tissues than females, with exception of the retrofrontalis fat and the frontalis muscle. CONCLUSION: On basis of the findings obtained in this study, basic treatment principles can be derived and improved for the injection of neuromodulators, hyaluronic acid as well as the application of polydiaxonane (PDO) threads and micro-focused ultrasound. Precise knowledge and thorough understanding of the layers and soft tissues of the forehead is required to guarantee safe and effective procedures in this aesthetically important facial region.

The Fascias of the Forehead and Temple Aligned-An Anatomic Narrative Review.

A thorough understanding of 3-dimensional facial anatomy and its fascial concepts is essential to allow for further development of novel surgical and nonsurgical treatment strategies to increase patient safety and effectiveness. The layered anatomy and its interconnections of the forehead, scalp, and temple is complex and is thus summarized and aligned in a unified nomenclature in this review. The scalp consists of 5 layers, which transition into 8 layers in the forehead and into a total of 13 layers in the temple.

Pinch Anatomy of Forehead: An Injection Guide for Forehead Filler Treatment.

Filler injections have become very popular in recent years, and injectors globally use them for facial shaping and reversing age-related changes. Detailed knowledge about important vessels' and tissue planes' anatomy is essential for injectors. While giving the filler injections, injectors tend to gently pinch or pull the tissue fold with the nondominant hand during the procedure. The deformational forces cause some changes in the anatomy of tissue layers held in a pinch. During the pinch and "pinch and pull" maneuver, the crucial vessels in the area can get pulled up in the tissue layers in a pinch or stay in their position unaffected depending on the force applied. The "pinch and pull" maneuver also increases the tissue space for injections by moving the mobile tissue layers away from the fixed ones. The injector can use knowledge of the "'pinch anatomy" in the forehead to avoid important arteries and place filler in the correct plane. With the understanding of the anatomical changes occurring during the pinched state of tissue layers, filler injection can be performed in the right and safer tissue plane in the forehead. This study reflects level of evidence V.

Reevaluation of the Layered Anatomy of the Forehead: Introducing the Subfrontalis Fascia and the Retrofrontalis Fat Compartments.

BACKGROUND: Novel imaging methods have provided new insights into the layered anatomy of the forehead. This study seeks to critically reevaluate the layered anatomy of the forehead by using ultrasound imaging and cadaveric dissection to provide an accurate anatomical description that can be used to guide safer surgical and minimally invasive frontal procedures. METHODS: This study used ultrasound imaging in a sample of 20 volunteers (12 female and eight male volunteers; aged 35.25 ± 4.2 years; body mass index, 24.28 ± 3.5 kg/m2) and cadaveric dissections of 16 body donors (12 female and four male body donors; aged 72.76 ± 9.5 years) to reevaluate the layered anatomy of the forehead. Layer-by-layer dissections and ultrasound-based measurements of the frontal structures guided conclusions. RESULTS: The following layered arrangement was identified: layer 1, skin; layer 2, superficial fatty layer; layer 3, suprafrontalis fascia; layer 4, orbicularis oculi and frontalis muscle (same plane); layer 5, a homogenous layer of fat [preseptal fat (in the upper eyelid), retro-orbicularis fat (deep to the orbicularis oculi muscle), and retro-frontalis fat (deep to the frontalis muscle); layer 6, subfrontalis fascia; layer 7, preperiosteal fat within the prefrontal space in the lower forehead and deep compartments in the upper forehead; and layer 8, periosteum. CONCLUSIONS: The results of this study add to the current understanding of the layered arrangement of the forehead. The combination of ultrasound imaging and cadaveric dissections provided evidence for a continuous fatty layer deep to the frontalis muscle.

Morphometric Variations and Growth Analysis of the Side Face Profiles of Chinese Children.

OBJECTIVE: We aim to use geometric morphometric methods to analyze the contours of the side face profile and its variations in 116 children in Hunan province, China, in order to reveal common morphological features and growth of the side face profiles of Chinese children. DESIGN: We photographed the side faces with consistent standardized procedures. Thirty-seven landmarks were recorded, which comprehensively reflected the facial sagittal plane. The collection of coordinate data regarding landmarks was conducted by tpsDig software. Other analyses, such as average shape analysis, principal component analysis, variations analysis, and allometric analysis, were conducted using tpsRelw and tpsRegr. RESULT: Based on the 37 landmarks, principal component analysis was used on the profiles of boys and girls. The result shows that PC1 and PC2 account for 35.46% and 27.44% of the side face contour variations, respectively. There is no significant difference in the side profiles of boys and girls. Overlapping distributions between the boys and girls occurred. A significant difference occurs when principal component analysis was used on the side profiles of children and adults. CONCLUSIONS: There is a significant difference in the side face profiles between adult males and females. Adult males have a higher brow (the 8th landmark) than females, and adult females have a more curved forehead. However, the side face profiles of boys and girls around 10 years of age are generally similar, which suggests that the significant difference in side face profiles between adult males and females may be formed after the age of 10. This study is of great significance for both orthodontists and pediatricians to use different norms for kids and adults and different norms for males and females for each of those age groups.

Evolution of Cranioorbital Shape in Nonsyndromic, Muenke, and Saethre-Chotzen Bilateral Coronal Synostosis: A Case-Control Study of 2-Year Outcomes.

BACKGROUND: The purpose of this study was to quantify change in cranioorbital morphology from presentation, after fronto-orbital advancement, and at 2-year follow-up. METHODS: Volumetric, linear, and angular analyses were performed on computed tomographic scans of consecutive bilateral coronal synostosis patients. Comparisons were made across three time points, between syndromic and nonsyndromic cases, and against normal controls. Significance was set at p < 0.05. RESULTS: Twenty-five patients were included: 11 were nonsyndromic, eight had Saethre-Chotzen syndrome, and six had Muenke syndrome. Total cranial volume was comparable to normal, age-matched control subjects before and 2 years after surgery despite an expansion during surgery. Axial and sagittal vector analyses showed advancement and widening of the lower forehead beyond control values with surgery and comparable anterior position, but increased width compared to controls at 2 years. Frontal bossing decreased with a drop in anterior cranial height and advanced lower forehead position. Middle vault height was not normalized and turricephaly persisted at follow-up. Posterior fossa volume remained lower at all three time points compared to control subjects. Supraorbital retrusion relative to anterior corneal position was overcorrected by surgery, with values comparable to those of control subjects at 2 years because of differential growth. There was no difference at 2 years between syndromic and nonsyndromic groups. CONCLUSIONS: Open fronto-orbital advancement successfully remodels the anterior forehead but requires overcorrection to be comparable to normal at 2 years. Although there are differences in syndromic cases at presentation, they do not result in significant morphometric differences on follow-up. Posterior fossa volume remains lower at all time points. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

School-Aged Anthropometric Outcomes After Endoscopic or Open Repair of Metopic Synostosis.

BACKGROUND AND OBJECTIVES: Metopic craniosynostosis can be treated by fronto-orbital advancement or endoscopic strip craniectomy with postoperative helmeting. Infants younger than 6 months of age are eligible for the endoscopic repair. One-year postoperative anthropometric outcomes have been shown to be equivalent, with significantly less morbidity after endoscopic treatment. The authors hypothesized that both repairs would yield equivalent anthropometric outcomes at 5-years postoperative. METHODS: This study was a retrospective chart review of 31 consecutive nonsyndromic patients with isolated metopic craniosynostosis treated with either endoscopic or open correction. The primary anthropometric outcomes were frontal width, interfrontal divergence angle, the Whitaker classification, and the presence of lateral frontal retrusion. Peri-operative variables included estimated blood loss, rates of blood transfusion, length of stay, and operating time. RESULTS: There was a significantly lower rate of lateral frontal retrusion in the endoscopic group. No statistically significant differences were found in the other 3 anthropometric outcomes at 5-years postoperative. The endoscopic group was younger at the time of surgery and had improved peri-operative outcomes related to operating time, hospital stay and blood loss. Both groups had low complication and reoperation rates. CONCLUSIONS: In our cohort of school-aged children with isolated metopic craniosynostosis, patients who underwent endoscopic repair had superior or equivalent outcomes on all 4 primary anthropometric measures compared with those who underwent open repair. Endoscopic repair was associated with significantly faster recovery and decreased morbidity. Endoscopic repair should be considered in patients diagnosed with metopic craniosynostosis before 6 months of age.

Superficial and Deep Facial Anatomy and Its Implications for Rhytidectomy.

The relationship of the skin, the superficial and deep fat compartments, and the ligaments that connect these structures is key to performing any rhytidectomy. In order to successfully mobilize, elevate, and reposition the facial soft tissues, a detailed understanding of facial anatomy is required. This article details the anatomy of the midface and neck that is essential to understanding and performing the face-lift operation.

Temporal volume increase after reduction of masseteric hypertrophy utilizing incobotulinumtoxin type A.

BACKGROUND: Treating the lower face with neuromodulators and targeting the masseter muscle can reduce masseteric hypertrophy but can also change the facial shape. A novel observation after the treatment of the masseter muscle with incobotulinumtoxin Type A was the increase in temporal volume. AIM: Objectively assess temporal volume increase following treatment of masseteric hypertrophy using incobotulinumtoxin Type A. METHODS: Nine female patients with a mean age of 35.11 years ± 9.1 [Asian (11.1%) and Caucasian (88.9%)] were treated with incobotulinumtoxin Type A for masseteric hypertrophy. Masseteric prominence and temporal volume were assessed by two independent raters, and temporal fossa volume was measured via 3-dimensional volumetric imaging. RESULTS: Independent of the neuromodulator injection technique (ie, single-injection versus multi-injection), a reduction in masseteric hypertrophy occurred represented by a decrease in the masseter prominence scale. In addition, the treatment resulted in a significant improvement of the temporal volume scale and an increase in the measured volume of the temporal fossa. None of the presented measurements were statistically significantly different between the two utilized injection techniques. CONCLUSIONS: This study supports using a full-face approach when performing aesthetic treatments. Anatomical concepts can help to guide treatments: the compensatory increase in temporalis function after masseter muscle treatment resulted in an increased in temporal fossa volume. The findings presented herein should not be considered as a new concept for treating the temporal fossa but rather as an additional possibility for increasing the temporal volume.

Repeated measurements of facial skin characteristics using the Janus-â ¢ measurement system.

BACKGROUND: For personalized skin care, noninvasive quantitative methods to evaluate facial skin characteristics are important. Janus-III is one of the most widely used imaging analysis devices in the skin care industry in Korea. Janus-III generates values for a range of skin characteristics. Due to the convenience of obtaining results for a variety of skin characteristics in a single measurement, the use of Janus-III in cosmetic stores and research institutes has been recently increasing. However, the consistency of skin measurements of Janus-III has not been elucidated yet. MATERIALS AND METHODS: In this study, we repeated skin measurements three times for 70 different subjects and compared each numerical value in order to assess the consistency of the Janus-III. For this purpose, we compared between-sample distances and within-sample distances. RESULTS: We found important patterns for future analyses in terms of consistency. First, the average values of skin measurement categories were more reliable than individual part values of facial segments. Second, center part values such as forehead and nose were more reliable than side part values such as left and right part segments. CONCLUSION: If researchers who use Janus-III for studies of facial characteristics analyze average and center part values first, they can obtain relatively reliable patterns of facial skin characteristics.

Three-Dimensional Territory and Depth of the Corrugator Supercilii: Application to Botulinum Neurotoxin Injection.

This study aimed to determine the three-dimensional (3D) territory and depth of the corrugator supercilii muscle (CSM) using a 3D structured-light scanner. Thirty-two hemifaces from Korean and Thai embalmed cadavers were used in this study, and 35 healthy young Korean subjects also participated. A 3D analysis of the CSM territory and depth was performed using a structured-light 3D scanner. The most frequently observed locations of the CSM identified in the cadaver were confirmed in healthy young subjects using a real-time two-dimensional B-mode ultrasonography system. The CSM was present in all of the cadavers and healthy young subjects at the intersection point between the vertical line passing through the medial canthus and the horizontal line passing through the glabella (Point #6). The CSM was located on the medial side of the lateral limbus in most cases. The most-medial and most-lateral origin points were at depths of 5.7 ± 1.4 mm (mean ± SD) and 6.6 ± 1.4 mm, respectively; the corresponding depths of the insertion points were 5.4 ± 1.4 mm and 5.6 ± 2.1 mm, respectively. The origin and insertion points of the CSM were at similar depths. The injection depth should be around 4 mm for botulinum neurotoxin (BoNT) injections into the CSM. Point #6 could be regarded as an effective target point for managing the glabellar frown line and preventing palpebral ptosis when injecting BoNT into the CSM. Clin. Anat., 33:795-803, 2020. © 2019 Wiley Periodicals, Inc.