Osseous genioplasty is the most versatile tool the plastic surgeon has for the lower face — and the most commonly mis-planned. In this episode of Plastics in Practice, we review the basics of chin surgery: when to pick the osteotomy over an implant, the five-pillar physical exam, the technical steps that decide your aesthetic result, and the pitfalls that cause the bizarre "overadvanced" chin we've all seen on revision.Key takeaways:• The lower lip rule: never advance the chin past a vertical line dropped from the lower lip. Cross it, and the result looks artificial every time.¹• 3-D versatility: implants only correct mild sagittal deficiency. Vertical excess, asymmetry, deep folds, or revisions belong to osseous genioplasty.²• Soft-tissue ratios: ~1:1 for advancement and lengthening; only ~0.5:1 for posterior repositioning.³• The 4 mm rule: keep the horizontal cut ≥ 4 mm below the mental foramina to protect the inferior alveolar nerve.⁴• Carry the cut posteriorly to the molars — the most common technical error is too short a cut, which produces an hourglass deformity.⁴• Mentalis discipline at closure prevents witch's chin (soft-tissue ptosis).⁵Disclaimer: This content is for educational purposes only and is not medical advice.🎧 Full episodes available now:Instagram: https://www.instagram.com/plasticsinpractice/ Spotify: https://open.spotify.com/show/4Ct8jOgYXP9QJin7QOuG3Z?si=JNcBxQmwT2mfz1LSJZEFKA Apple: https://podcasts.apple.com/us/podcast/plastics-in-practice-resident-review/id1835564216 YouTube: https://youtube.com/@plasticsinpractice?si=tqLInp5vvsJFKlRO Amazon: https://music.amazon.com/podcasts/8bef056e-7c87-4224-978e-7e691b04554a/ 📘 Free Study Guides: → https://drive.google.com/drive/u/0/folders/12BUldPbCmihG-ndZh6992WqhRYyxw8ZZ#PlasticSurgery #Residency #Genioplasty #Craniofacial #SurgicalEducation #PlasticsInPractice #FacialAesthetics #ChinSurgeryReferences (AMA):1. Rosen HM. Aesthetic guidelines in genioplasty: the role of facial disproportion. Plast Reconstr Surg. 1995;95(3):463-469.2. Converse JM, Wood-Smith D. Horizontal osteotomy of the mandible. Plast Reconstr Surg. 1964;34:464.3. Rosen HM. Aesthetic refinements in genioplasty: the role of the labiomental fold. Plast Reconstr Surg. 1991;88(5):760-767.4. Spear SL, Mausner ME, Kawamoto HK. Sliding genioplasty as a local aesthetic outpatient procedure: a prospective two center trial. Plast Reconstr Surg. 1987;80(1):55-59.5. Zide BM, McCarthy JG. The mentalis muscle: an associated component of chin and lower lip position. Plast Reconstr Surg. 1989;83(3):413-420.