Chin augmentation | |
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Specialty | plastic surgery |
ICD-9-CM | 76.68 |
MedlinePlus | 002986 |
Chin augmentation using surgical implants alter the underlying structure of the face, intended to balance the facial features. The specific medical terms mentoplasty and genioplasty are used to refer to the reduction and addition of material to a patient's chin. This can take the form of chin height reduction or chin rounding by osteotomy, or chin augmentation using implants. Altering the facial balance is commonly performed by modifying the chin using an implant inserted through the mouth. The intent is to provide a suitable projection of the chin as well as the correct height of the chin which is in balance with the other facial features. [1]
This operation is often, but not always, performed at the time of rhinoplasty to help balance the facial proportions. Chin augmentation may be achieved by manipulation of the jaw bone (mandible) and augmentation utilizing this technique usually provides a more dramatic correction than with the use of prosthetic implants.
Chin implants are used in the cosmetic industry to alter one's profile [2] to resolve confidence and self-esteem issues by the physical augmentation of an individual's jawline and neck. [3] Patients' own bone is donated from ribs and from part of the pelvis (the ilium). Use of donated bone implants in chin augmentation, even the patient's own, appears to be associated with a higher rate of infection, even after the implant has been in place for decades.
Chin augmentation is still popular because it is a relatively easy operation for the patient while producing noticeable changes in the silhouette of the face. This type of surgery is usually performed by an oral and maxillofacial surgeon, otolaryngologist, or plastic surgeon.
T-osteotomy method (or mini V-line) [4] is used to narrow and lengthen the chin using an osteotomy technique formulated by Korean surgeons. The surgery is performed under general anesthesia (orotracheal intubation) using an intraoral approach. [5] Using a double-bladed reciprocating saw, [6] a horizontal osteotomy is performed, leaving a small portion of bone in the middle. Then two vertical osteotomies are performed in an upside-down trapezoidal shape which is excised. The bones remaining from the horizontal osteotomy are then attached and adjusted to lengthen the chin, and advanced forward for an additional frontal chin projection if required. [5] Pre-bent titanium plates and screws are used to fixate the bone to its new position. [6] The chin can be lengthened 2 to 3 mm on average. [7]
The mentalis muscles controls the elevation functions of the lower lip and chin, so extra caution should be taken to carefully attach the mentalis muscle back after the surgery. [8] [9]
The usual complications are relatively minor and include swelling, hematoma (blood pooling), weakness or numbness of the lower lip, which usually does not last long. Other, less common risks include infection, bony changes, displacement of the implant, and nerve damage. [10] Surgeon experience can help reduce risks of complications. [11]
Chewing should be kept at a minimum immediately after this procedure, and patients are recommended to eat only soft food and drink for a time after the surgery.
Silicone - Silicone chin Implants are one of the most commonly used implants for chin augmentation. They are soft, smooth, flexible and come in different shapes and sizes. They do not incorporate (stick) to the surrounding tissues, so the pocket must be made precisely. They usually stay in place, but may move, buckle and cause bone resorption where they contact the mandible in some cases. Since they are smooth, they can also be removed easily.
Polyethylene - Polyethylene chin implants, brand name Medpor, are hard, porous, slightly flexible and come in various shapes and sizes. They do incorporate, as the surrounding tissues can grow into the pores of the material. This fixes the polyethylene chin implants in place, and provides a blood supply to help prevent infection. It also makes these implants much more difficult to remove.
Polytetrafluoroethylene - Polytetrafluoroethylene, brand name Gore-Tex, is used in plastic surgery and other operations is known by an abbreviation of its chemical name, ePTFE (expanded polytetrafluoroethylene) or Gore S.A.M. (subcutaneous augmentation material). [12] Because ePTFE is flexible and soft but very strong, it is inserted during operations in trimmed sheets and carved blocks and held to the bone by titanium screws. But because the material is porous, the force that really holds the implant in place is soft tissue and bone growing through and into the implant.
The above artificial materials are used in medicine because they are biocompatible and have a low incidence of causing problems inside the human body. They are abundant, FDA cleared and can be used "off-the-shelf", without a donor site injury to the recipient.
Acellular dermal matrix - ADMs are another chin augmentation implant material. Commercially known as AlloDerm and known to physicians as acellular human cadaveric dermis, AlloDerm comes from tissue donors Just after death, technicians remove a layer of skin, remove the epidermis, and treat the remaining dermis with antibiotics and other substances to remove the donor's cells and DNA that would cause rejection. The graft that emerges is often used to cover chin implants.
Other implant materials include Supramid, a braided nonabsorbable synthetic suture material in polymer shell and Mersiline, a mesh-like material that provides a scaffold on the bone. [13]
Surgical chin augmentation - The most common type of surgical chin augmentation uses a chin implant. There are many types of chin implants, and many are described in the previous section. Chin augmentation with a chin implant is usually a cosmetic procedure. An incision is made either under the chin or inside the lower lip, a pocket is made and the implant placed into the pocket. Some chin implants are fixed to the mandible, while others are held in place by the pocket itself.
Another surgical chin augmentation uses the lower prominence of the mandible as the "implant." Known as a sliding genioplasty, the procedure involves cutting a horseshoe-shaped piece of bone from the lower border of the mandible known as an osteotomy. For chin augmentation, the piece of bone is advanced forward to increase to projection of the chin. The piece can also be recessed backward for a chin reduction. The new position is held in place with a titanium step plate using titanium screws. The bone segment can also be fixated with 26 or 27 gauge wires and IMF (wiring the jaw shut) for 3-4weeks. This type of surgery is usually performed by an oral and maxillofacial surgeon or a plastic surgeon.
More involved Orthognathic Surgery may be required in cases where the chin is small and a significant overbite co-exist. While the procedures above may improve the cosmetic appearance of the chin, they will not improve dental occlusion. Mandibular advancement surgery can be used to correct the alignment of the teeth and improve the projection of the chin.
Non-surgical chin augmentation - Another method of chin augmentation uses an injectable filler. Most fillers are temporary, with results lasting months to years. Common temporary fillers include hyaluronic acid and calcium hydroxyapatite preparations. Permanent fillers, like "free" silicone, have fallen out of favor due to the risk of migration, chronic inflammation and infection, which can permanently disfigure the chin.
Plastic surgery is a surgical specialty involving the restoration, reconstruction or alteration of the human body. It can be divided into two main categories: reconstructive surgery and cosmetic surgery. Reconstructive surgery includes craniofacial surgery, hand surgery, microsurgery, and the treatment of burns. While reconstructive surgery aims to reconstruct a part of the body or improve its functioning, cosmetic surgery aims to improve the appearance of it. A comprehensive definition of plastic surgery has never been established, because it has no distinct anatomical object and thus overlaps with practically all other surgical specialties. An essential feature of plastic surgery is that it involves the treatment of conditions that require or may require tissue relocation skills.
Facial feminization surgery (FFS) is a set of reconstructive surgical procedures that alter typically male facial features to bring them closer in shape and size to typical female facial features. FFS can include various bony and soft tissue procedures such as brow lift, rhinoplasty, cheek implantation, and lip augmentation.
An osteotomy is a surgical operation whereby a bone is cut to shorten or lengthen it or to change its alignment. It is sometimes performed to correct a hallux valgus, or to straighten a bone that has healed crookedly following a fracture. It is also used to correct a coxa vara, genu valgum, and genu varum. The operation is done under a general anaesthetic.
Breast augmentation and augmentation mammoplasty is a cosmetic surgery technique using breast-implants and fat-graft mammoplasty techniques to increase the size, change the shape, and alter the texture of the breasts. Augmentation mammoplasty is applied to correct congenital defects of the breasts and the chest wall. As an elective cosmetic surgery, primary augmentation changes the aesthetics – of size, shape, and texture – of healthy breasts.
A dental implant is a prosthesis that interfaces with the bone of the jaw or skull to support a dental prosthesis such as a crown, bridge, denture, or facial prosthesis or to act as an orthodontic anchor. The basis for modern dental implants is a biological process called osseointegration, in which materials such as titanium or zirconia form an intimate bond to the bone. The implant fixture is first placed so that it is likely to osseointegrate, then a dental prosthetic is added. A variable amount of healing time is required for osseointegration before either the dental prosthetic is attached to the implant or an abutment is placed which will hold a dental prosthetic/crown.
Oral and maxillofacial surgery is a surgical specialty focusing on reconstructive surgery of the face, facial trauma surgery, the oral cavity, head and neck, mouth, and jaws, as well as facial cosmetic surgery/facial plastic surgery including cleft lip and cleft palate surgery.
Orthognathic surgery, also known as corrective jaw surgery or simply jaw surgery, is surgery designed to correct conditions of the jaw and lower face related to structure, growth, airway issues including sleep apnea, TMJ disorders, malocclusion problems primarily arising from skeletal disharmonies, and other orthodontic dental bite problems that cannot be treated easily with braces, as well as the broad range of facial imbalances, disharmonies, asymmetries, and malproportions where correction may be considered to improve facial aesthetics and self-esteem.
Lip augmentation is a cosmetic procedure that modifies the shape of the lips using fillers, such as collagen or implants. The procedure may be performed to increase lip size, correct asymmetry, create protrusion, or adjust the ratio of the top and bottom lips. The procedure typically involves surgical injection, though temporary non-surgical alternatives exist.
Gluteoplasty denotes the plastic surgery and the liposuction procedures for the correction of the congenital, traumatic, and acquired defects and deformities of the buttocks and the anatomy of the gluteal region; and for the aesthetic enhancement of the contour of the buttocks.
Cheek augmentation is a cosmetic surgical procedure that is intended to emphasize the cheeks on a person's face. To augment the cheeks, a plastic surgeon may place a solid implant over the cheekbone. Injections with the patients' own fat or a soft tissue filler, like Restylane, are also popular. Rarely, various cuts to the zygomatic bone (cheekbone) may be performed. Cheek augmentation is commonly combined with other procedures, such as a face lift or chin augmentation.
Jaw reduction or mandible angle reduction is a type of surgery to narrow the lower one-third of the face—particularly the contribution from the mandible and its muscular attachments. There are several techniques for treatment—including surgical and non-surgical methods. A square lower jaw can be considered a masculine trait, especially in Asian countries. As a result, whereas square lower jaws are often considered a positive trait in men, a wide mandible can be perceived as discordant or masculine on women, or sometimes in certain men, particularly when there is asymmetry.
Guided bone regeneration (GBR) and guided tissue regeneration (GTR) are dental surgical procedures that use barrier membranes to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics or prosthetic restoration. Guided bone regeneration typically refers to ridge augmentation or bone regenerative procedures; guided tissue regeneration typically refers to regeneration of periodontal attachment.
Bone segment navigation is a surgical method used to find the anatomical position of displaced bone fragments in fractures, or to position surgically created fragments in craniofacial surgery. Such fragments are later fixed in position by osteosynthesis. It has been developed for use in craniofacial and oral and maxillofacial surgery.
Zygoma reduction, also known as cheekbone reduction surgery, is a surgery used to reduce the facial width by excising part of the zygomatic bone and arch. Wide cheekbones are a characteristic facial trait of Asians, whose skull shapes tend to be more brachycephalic in comparison with Caucasian counterparts, whose skull shapes tend to be more dolichocephalic .This surgery is popular among Asians due to their inherent wide cheekbones. Due to the advanced surgical skills of Korean surgeons who perform facial contouring surgeries, the number of Asian people undergoing this surgery is increasing.
Facial implants are used to enhance certain features of the face. The surgery may be elective, or needed as the result of prior surgery on the face. Each involves placing synthetic materials deep under the subcutaneous tissue and onto the underlying bone. A maxillofacial or plastic surgeon uses them to aesthetically improve facial contours, proportion and correct imbalances caused by injury or hereditary traits. However, in cases that require orthognathic osteotomies, those should be done before any implants are considered.
A lip lift is a plastic surgery procedure that modifies the cosmetic appearance of the lips by reshaping them to increase the prominence of the vermilion border; and to enhance the facial area above the lips into a more aesthetically pleasing shape. In corrective praxis, a lip lift procedure is distinguished from lip enhancement, the augmentation of the lips, which can be effected with a non-surgical procedure.
Non-surgical rhinoplasty is a medical aesthetic procedure in which injectable fillers, most commonly hyaluronic acid ones like Restylane and Juvederm or calcium hydroxyapatite (Radiesse), are used to alter and shape a person's nose without a surgery. The procedure fills in depressed areas on the nose, lifting the angle of the tip or smoothing the appearance of bumps on the bridge. Non surgical rhinoplasty is an augmentation procedure, so it cannot reduce the size of someone's nose. The cosmetic procedure carries the risk of causing serious skin damage or distant complications like blindness. If the filler product is injected into an artery, filler can travel in the arteries and blocks smaller size arteries like ophthalmic artery and cause blindness. If blood vessels of the skin is blocked, skin necrosis can develop. Hyaluronic acid based fillers can be reversed even if injected into a blood vessel with an enzyme called hyaluronidase, which can be also injected like fillers.
Facial masculinization surgery (FMS) is a set of plastic surgery procedures that can transform the patient's face to exhibit typical masculine morphology. Cisgender men may elect to undergo these procedures, and in the context of transgender people, FMS is a type of facial gender confirmation surgery (FGCS), which also includes facial feminization surgery (FFS) for transgender women.
Alloplasty is a surgical procedure performed to substitute and repair defects within the body with the use of synthetic material. It can also be performed in order to bridge wounds. The process of undergoing alloplasty involves the construction of an alloplastic graft through the use of computed tomography (CT), rapid prototyping and "the use of computer-assisted virtual model surgery." Each alloplastic graft is individually constructed and customised according to the patient's defect to address their personal health issue. Alloplasty can be applied in the form of reconstructive surgery. An example where alloplasty is applied in reconstructive surgery is in aiding cranial defects. The insertion and fixation of alloplastic implants can also be applied in cosmetic enhancement and augmentation. Since the inception of alloplasty, it has been proposed that it could be a viable alternative to other forms of transplants. The biocompatibility and customisation of alloplastic implants and grafts provides a method that may be suitable for both minor and major medical cases that may have more limitations in surgical approach. Although there has been evidence that alloplasty is a viable method for repairing and substituting defects, there are disadvantages including suitability of patient bone quality and quantity for long term implant stability, possibility of rejection of the alloplastic implant, injuring surrounding nerves, cost of procedure and long recovery times. Complications can also occur from inadequate engineering of alloplastic implants and grafts, and poor implant fixation to bone. These include infection, inflammatory reactions, the fracture of alloplastic implants and prostheses, loosening of implants or reduced or complete loss of osseointegration.
Mandibular setback surgery is a surgical procedure performed along the occlusal plane to prevent bite opening on the anterior or posterior teeth and retract the lower jaw for both functional and aesthetic effects in patients with mandibular prognathism. It is an orthodontic surgery that is a form of reconstructive plastic surgery. There are three main types of procedures for mandibular setback surgery: Bilateral Sagittal Split Osteotomy (BSSO), Intraoral Vertical Ramus Osteotomy (IVRO) and Extraoral Ramus Osteotomy (EVRO), depending on the magnitude of mandibular setback for each patient. Postoperative care aims to minimise postoperative complications, complications includes bite changes, relapse and nerve injury.