A square face (masseteric hypertrophy) is a wide lower-jaw region with a squared lower-third contour — an overdeveloped masseter (chewing muscle) is the main cause, making the jaw angle protrude in frontal view and the face look wider in photos. Causes include: (1) Developed masseter — prolonged chewing of hard foods (gum, nuts, dried squid), bruxism, or one-sided chewing over-exercising the muscle. (2) Congenital bone — a naturally wide and everted mandibular angle (skeletal), where the face looks wide even with normal muscles. (3) Mixed — wide bone plus muscle hypertrophy, the most common type. Previously square faces required surgery (mandibular angle osteotomy); now botox masseter reduction is mainstream: the toxin blocks nerve signals, temporarily relaxing and shrinking the overdeveloped masseter — non-surgical, 15 minutes, no downtime, with the face visibly becoming V-shaped in 4-8 weeks. Rappoel Dermatology near Gangnam Station, Seoul, provides botox square-face improvement treatment.
Technical Principles of Botox Masseter Reduction
- Muscle relaxation and atrophy: An overdeveloped masseter protrudes the jaw angle — toxin injected into the thickest part blocks acetylcholine release, so the muscle receives no contraction signal and relaxes; with prolonged disuse it gradually atrophies (shrinks), softening the jaw angle contour
- Precise localization: The patient bites down firmly before injection while the physician palpates and marks the thickest masseter area (usually just above and in front of the angle) — 2-3 points per side, 20-40 units per side (Coretox/Botox), avoiding too-high placement that could affect the smile (facial nerve branches)
- Dose-response relationship: Larger masseters need higher doses — first treatment is typically 30 units per side, with top-ups at 1 month if insufficient; excessive doses may affect chewing (soft food fine, hard food more effortful), while low doses give subtle results
- Gradual effect: Masseter relaxation is felt in 2-4 weeks, facial change peaks at 4-8 weeks (atrophy peak), best results at 12-16 weeks — unlike wrinkle treatment (1-2 weeks), slimming is a ‘gradual’ change
- Reversible and safe: Effects last 6-12 months (about 6 months after the first session), with gradual muscle recovery afterward — regular touch-ups maintain the V-line, no surgical risk, and stopping simply restores the original state
Treatment Strategies for Different Square-Face Types
- Developed masseter (muscular): The jaw angle visibly bulges on firm biting. Strategy: 20-40 units per side — the angle clearly softens after atrophy, with the best results
- Wide bone (skeletal): The mandibular angle bone itself is wide and everted. Strategy: the toxin only partially helps (the muscle part) — bone width cannot be changed by toxin; Rappoel honestly explains that if skeletal dominance is obvious, toxin results are limited, requiring surgical evaluation or acceptance of the status quo
- Mixed type (bone + muscle): The most common type. Strategy: toxin for the masseter plus evaluation of the bone component — usually achieving an obvious ‘softened jaw angle’ visual improvement with a clearer V-line
- Square face with blurred jawline: Masseter hypertrophy plus unclear jawline contour. Strategy: masseter injection plus HA jawline injection (strengthening the contour) — simultaneous slimming and contour sculpting for a more sculpted V-line
- Square face with facial fullness (fatty): Thick fat over the jaw angle. Strategy: masseter injection as the base plus fat assessment — the toxin has no direct fat effect; lipolysis (Onda) or overall weight loss may be combined; Rappoel distinguishes the muscle/fat contribution during consultation
Rappoel Botox Slim-Face Protocol
- Consultation assessment (5 min): Frontal evaluation of jaw angle width and face shape → palpate the masseter (firm-bite test) to assess hypertrophy → distinguish muscular/skeletal/fatty square face → design the dose plan
- Cleansing and marking (3 min): Makeup removal → alcohol disinfection → patient bites down firmly while the physician palpates and marks the thickest masseter points (2-3 per side)
- Precise injection (10 min): Inject at the marked points → 20-40 units per side → brief gentle pressure → avoid rubbing to prevent spread
- Post-care instructions (2 min): Avoid lying flat and strenuous exercise for 4 hours → avoid pressing the area, sauna, and alcohol for 24 hours → avoid hard chewing for 1 week (let the muscle fully relax) → face gradually becomes V-shaped in 4-8 weeks; 1-month follow-up to assess whether a top-up is needed
Botox slimming takes about 15 minutes with no downtime; the face gradually becomes V-shaped in 4-8 weeks, lasting 6-12 months. Located 3 minutes from Gangnam Station Exit 10, with seamless English and Chinese consultation.
Frequently Asked Questions
What’s the difference between botox slimming and jaw reduction surgery (mandibular angle osteotomy)?
Different candidates and effects: (1) Botox slimming — targets ‘masseter hypertrophy’: blocks nerve signals to relax and shrink the muscle; suitable for muscular square faces. Non-surgical, 15 minutes, no downtime, gradually V-shaped in 4-8 weeks, lasting 6-12 months with regular touch-ups, reversible (stopping restores the original). (2) Jaw reduction surgery — targets ‘wide bone’: removes part of the mandibular angle; suitable for skeletal square faces. Surgical, general anesthesia, 2-4 weeks recovery, permanent. (3) Clinical key — most square faces are muscle-plus-bone: do botox first to reveal the true bone contour after muscle shrinkage, then judge whether the bone warrants surgery. (4) Rappoel’s recommendation — botox first (safe, reversible, affordable); if satisfied, maintain with regular touch-ups; if the bone still looks wide after muscle reduction, then consider surgical evaluation.
How soon do botox slimming results appear? How long do they last?
Timeline: (1) 2-4 weeks — masseter relaxation is felt with easier chewing; external change is still subtle. (2) 4-8 weeks — atrophy peaks; the jaw angle clearly softens and the face begins to look V-shaped with obvious photo comparison. (3) 12-16 weeks — best results with a fully visible V-line. (4) Duration — about 6 months after the first session (muscles need time to re-train), with subsequent touch-ups potentially lasting longer (long-term relaxation habit). (5) Recommendation — regular touch-ups (every 6-9 months) stably maintain the V-line; those who stop will see the muscle recover within months with no permanent change. (6) Individual variance — related to hypertrophy degree, dose, and metabolism; Rappoel evaluates actual results at the 1-month follow-up.
Will botox slimming affect chewing? Will the face become hollow?
Functional impact and side effects: (1) Chewing — the toxin only relaxes the masseter without affecting teeth or the TMJ: soft food is completely normal; only hard food (beef jerky, nuts) feels more effortful, generally acceptable. (2) Dose safety — Rappoel uses conservative yet effective doses (20-40 units per side), balancing efficacy and function. (3) Side effects — mild swelling and bruising at injection points (3-5 days), chewing soreness (1-2 weeks), and extremely rare smile asymmetry (injection placed too high affecting expression muscles; avoidable by experienced physicians). (4) ‘Hollow cheeks’ — does not occur with correct dosing and placement; it usually results from excessive dose or wrong placement (over-injection of the upper masseter) — choosing an experienced physician is key. (5) Rappoel injects around the thickest masseter center, avoiding expression-muscle areas for safety and naturalness.
Who is suitable for botox slimming? Who is not?
Suitable and unsuitable groups: (1) Suitable — masseter-hypertrophy square faces, obvious jaw-angle bulge on firm biting, faces looking big in photos, those avoiding surgery, and those with bruxism/tension-related jaw soreness (the toxin also therapeutically relaxes the muscle). (2) Unsuitable or cautious — predominantly skeletal square faces (limited results), pregnancy and breastfeeding (postpone), neuromuscular diseases such as myasthenia gravis (contraindicated), infection at the injection site (treat first), toxin allergy, and predominantly fatty facial fullness (reduce fat first). (3) Rappoel physicians distinguish the true cause of a wide face (muscle/bone/fat) during consultation and recommend toxin only for suitable candidates, avoiding wasted expense.
What should I do after botox slimming? Can I eat right away?
Post-care: (1) 4 hours — avoid lying flat, face-down sleeping, strenuous exercise, and facial massage (preventing spread to non-target areas). (2) 24 hours — avoid pressing the area, sauna, high-temperature environments, and alcohol. (3) One week — avoid hard chewing (gum, nuts, dried squid) so the masseter fully relaxes and the effect fully works; soft and normal meals are fine. (4) Effect observation — the face visibly changes after 1 month; if insufficient, return for a dose evaluation (at least 1 month apart). (5) Long term — effects last 6-12 months; schedule touch-ups before they fade; reducing hard-chewing habits prolongs results and prevents recurrence.
Square jaw making you look big in photos? Rappoel botox masseter reduction — 15 minutes to a soft V-line!
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