Chin Ptosis: The Unabridged Version
Barry M. Zide, DMD, MD, Evan S. Garfein, MD.
NYU, New York, NY, USA.
Purpose: This study develops a systematic approach for the categorization and treatment of chin ptosis. Chin ptosis describes the presence of the presymphyseal soft tissues below the inferior mandibular border. The four types of chin ptosis consist of 1) Illusory, 2) Developmental, 3) Iatrogenic, and 4) Dynamic. This paper describes the normal and abnormal anatomy for each, diagnosis, and management of the subtypes.
Methods: A retrospective review was conducted of the senior surgeon’s case records between 1999 and 2007. A total of 300 patients underwent correction of various types of chin deformities. Pre- and post-operative photographs were examined and patients were placed into one of four categories depending on types of ptosis on presentation.
Results: General guidelines for the correction of each subtype were developed.
Illusory ptosis describes the perceived descent of the chin. It is caused by an exaggerated submental crease which may extend cephalad over the inferior mandibular border on each side. The patient has usually not had surgery. The solution is to eliminate the submental crease and undermine the soft tissues up onto the face to allow redraping of tissues. Methods have previously been described.i
Developmental or Acquired ptosis is caused by the traumatic lowering of the upper stabilizing attachments of the mentalis muscle on the anterior alveolus. This is usually caused by boney absorption and fiber push-down after tooth loss, resorption of a thin alveolus, and improper denture fitting. There is only one stabilizing treatment- reduce further bone loss.
Iatrogenic ptosis occurs after resection of the mentalis muscles, improper reattachment following the intraoral approach to the chin, avascular muscle origin atrophy, descent of the origin secondary to multiple surgical incisions, vestibuloplasty, removal of an overly large implant, or overresection of the bone without soft tissue support. Treatment is resuspension of the mentalis muscles to the high point on the alveolus combined with increased inferior support.
Dynamic ptosis connotes an effacement of and drop of the soft tissues of the chin-pad when certain people smile. This type of ptosis can be either natural or acquired, even accentuated after procedures such as bone reduction. The solution is based on the patient’s specific boney and soft-tissue anatomy and surgical history.
Conclusions: The senior author’s experience has led to certain principles of correction. The intraoral route of access to the chin often involves division of the mentalis muscles. An extraoral, submental approach avoids mentalis problems and results in a well-hidden, acceptable scar. Revising chin implants is better with a well-secured implant or osteotomy advancement than with no implant. Management of iatrogenic ptosis involves anchoring the mentalis muscles to the alveolus at the appropriate level with wide undermining of the soft tissues well beyond the submentum to the platysma to allow redraping. Cases and surgical methods will be demonstrated.
Endnotes
i Lesavoy MA, Creasman C, Schwartz RJ. A technique for correcting witch's chin deformity.
Plast Reconstr Surg. 1996 Apr;97(4):842-6.