The traditional chin bone procedure for aesthetic enhancement is that of a sliding genioplasty. Cutting the chin bone and moving it forward has been a facial bone reshaping procedure that has been done for over half a century. It is mainly used as a bony alternative to a synthetic chin implant for chin augmentation. It is less frequently done for reductive chin procedures not only because there is less need but there is generalized less public and even surgeon awareness.
Reducing the bony chin works best for reducing its height and/or width. Moving the bone back for horizontal chin reduction is fraught with causing other soft tissue problems. Such bony chin manipulations have achieved greater awareness more recently due to the popularity of the so called ‘V-line’ Jaw surgery. While frequently used in Asians to reduce their wide and prominent jawlines, it is becoming more common to use it in females with a large lower jaw of any ethnicity.
A fundamental component of V-line jaw surgery is in how the front part of the jaw, the chin, is reduced. To shorten and narrow it the type of osteotomy pattern (bone cuts) must be different than the traditional sliding genioplasty. While a horizontal bone cut is still used, a double horizontal bone is used to reduce the vertical chin height. The space between the bone cut depends on how much vertical height needs to be shortened. The down fractured chin segment is then cut vertically in two parallel cuts whose space between them is the amount of chin width that has been predetermined to be reduced.
This leaves the chin in three pieces; a stable fixed upper segment and two smaller mobile lower segments. The three bone segments are brought together with midline alignment of the two lower segments and fixed together by a single plate and screws. The bone cut patterns and how the chin is put back together creates the T-shape.
Since the chin width is narrowed by sliding the bone segments to the middle, there is often a step off along the lower edge of the jawline at the back end of the horizontal osteotomy line. Care must be taken to look for it and reduce it if needed.
The success of this type of chin reduction depends on how much bone is removed and how well the overlying soft tissue adapts to a smaller underlying bone support.
Dr. Barry Eppley
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Background: Chin augmentation is one of the most common facial reshaping procedures both historically and to the present day. While augmenting the chin is a straightforward procedure using a variety of implant shapes, management of the large chin (macrotia) is a completely different story. Not only is it less commonly needed but the procedure to do it are not well understood.
The traditional and often chosen procedures for macrogenia are intraoral approaches either shaving or cutting the bone and moving it back. Shaving the chin bone intraorally is a simple procedure and seems like it would work…but it doesn’t. It consistently leads to soft tissue chin ptosis as the degloving of the soft tissues and the soft tissue excess creates a soft tissue sag off of the bone. A bony genioplasty has a role in vertical and width reduction of the chin. (V line jaw surgery) But doing a sliding genioplasty and moving it backwards for too much horizontal projection create sa relative soft tissue excess. This results in the excessive soft tissue being relocated to a bulge under the chin.
The submental chin reduction is a technique that addresses both the bone and soft tissue aspects of a large chin. Using an incision below the chin, the bony chin can be reduced by shaving or burring the chin in all three dimensions. Once the bone is reduced, the excess soft tissue created can be managed by a submental tuck which redrapes the soft tissue over the remodeled chin bone.
Case Study: This 25 year-old female had a prior history of a vertical reduction boy genioplasty done to reshape a large chin. It failed to achieve its desired aesthetic goals and actually made the chin wider as it vertically shortened it, exaggerating the patient’s original aesthetic chin concerns.
Under general anesthesia, a submental incisional approach was used to expose the bony chin. The incisional length was 4 cms and stayed well within vertical lines dropped down from the corners of the mouth. The bony was burred down horizontally and in width. The sides of the chin was taken down back behind the mental nerves removing the stepoffs from the prior chin osteotomy.
Her submental chin reduction results after three months showed improvement in the shape of the chin being smaller in horizontal projection and in its width.
1) Chin reduction is a challenging procedure because of the need to manage the excess soft tissue as well as that of the bone.
2) A submental chin reduction allows for reduction of both the bone and the soft tissue chin pad.
3) A submental chin reduction allows for 3D reshaping of the chin bone including length, projection and width.
Chin reduction surgery is sought for those patinets afflicted with a chin that is too strong or protrusive. A large chin can exist in numerous dimensions, albeit being vertically too long, too horizontally forward or too wide. In many cases the chin protrusion is caused by at least two and sometimes all three dimensional excesses.
Intraoral chin reduction is reserved for a minority of large chin patients. A chin that is too vertically long can be reduced by a wedge reduction bony genioplasty. But chins that are too far forward should not be reduced by shaving or setback genioplasties. This will lead to soft tissue chin problems of redundancies and/or chin ptosis. (sagging)
A submental chin reduction is the most effective technique for a chin that needs multiple dimensional changes. It is preferred because it can deal with the resultant soft tissue excess that results from loss of bone support. It also provides direct access for reducing the jawline behind the chin along the inferior border.
The best and simplest method for estimating and planning the bone removal in a submental chin reduction is a panorex x-ray. This x-rays provides visualization of the important mental nerve as it courses through the bone.
With x-ray planning as a precise guide, the measurements can be transferred to the bone during the chin reduction surgery. This will allow the maximum amount of bone removal while protecting the integrity of the mental nerve as it courses through the jawbone.
An after surgery x-ray shows the execution of the exact bone removal plan and how close the path of the nerve is to the underlying bone cut. Comparison of the preoperative planning panorex to the result seen in the after surgery panoex shows how well the surgical bone removal was done.
The use of a panorex x-ray in submental chin reduction is a valuable presurgical tool which is of greatest importance when bone needs to be removed along the jawline behind the chin.
The treatment of macrogenia (large chin) is much different than that of microgenia (small chin) and is also more challenging. Expanding the chin (chin augmentation) can done very reliably and in a straightforward manner through an implant or sliding genioplasty as it pushes out the overlying skin and soft tissue. While a prominent chin bone can be reduced, the success of any chin reduction procedure usually depends on what happens to the resultant excess soft tissue that will result from loss of bone support.
While a few limited chin reductions can be done from an intraoral approach, significant chin reductions require a different approach for two reasons. First, significant chin reduction requires a multi-dimensional approach to the bone reduction. This often includes horizontal, vertical and width bone removals. If the surgeon is skilled in bony genioplasty techniques and the patient is young, an intraoral vertical and midline wedge bone removals can reshape a large chin. But the best access to doing every dimension of bony chin change is from a submental approach from below. Secondly, any successful management of excess chin soft tissue involves excision which can only be done from below. Resuspension or ‘tightening’ of chin tissues done intraorally is not really an effective method making the chin soft tissues less in volume.
A submental chin reduction has several key technical steps to be successful. These include the location and extent of the incision, the method of bone removal and tye closure method which includes a submental tuck-up procedure,
The submental incision needs to precisely placed and put back a few millimeters further that the standard submental skin crease (many young people do not have such a crease) The curve of the inferior border of the jawline is marked out and the submental incision placed 5 to 10mms behind it. Its length is no greater than 3.5 cms and is curved to follow the curve of the jawline.
The submental skin incision allows direct access to the entire bottom of the chin which is done through wide subperiosteal undermining. A reciprocating saw is the most reliable way to make horizontal, vertical and width bone reduction with little risk of damaging the skin edges of the relatively small access incision. Burring can be done to smooth out all reduced bone edges. The bone should only be reduced until the marrow spaces are encountered where some bleeding will occur. That can easily be controlled by bone wax.
After chin reduction and reshaping the soft tissue chin pad is pulled over the reduced bone and its mentalis muscle edges sewn to either the bone edges (through drilled bone holes or to the muscle and periosteam on the underside of the bone edge. This fixes the anterior edge of the submental incision. The excess submental tissues behind the incision are advanced forward and the ‘excess tissues’ are trimmed and the incision closed. Rather than removing the redundant chin soft tissue pad, they are redraped over the reduced chin bone. This ensures that the submental incision is moved behind the new inferior border of the chin and the now ‘fuller’ neck tissues are removed and brought forward.
The technique for submental chin reduction is not well described or frequently performed. But careful attention to detail can create a submental scar that is both very aesthetically acceptable and not overly long.
Shaping of the jawline is done for many different reasons. The most common reason worldwide is tapering a wide jawline through a combination of a chin reduction osteotomies and jaw angle shaves or ostectomies. In other patients with just a large or long chin, a chin reduction osteotomy is used.
When the chin is vertically reduced the osteotomy line usually extends to the inferior border of the jawline below the mental foramen or even more posterior. Depending on the amount of vertical chin bone reduction and the angle of the bone cut, the line of the jawline from the jaw angle (back) to the chin.(front) can become non-linear. A bump along the lower edge of the jawline behind the chin can occur because of the location of the vertical reduction. (anterior) This makes the chin vertically shorter in the front but boxy in shape and a fullness (bump) behind the chin on the jawline.
Reduction of this bump or hump on the jawline is best done through a submental approach. This provides the most direct access which is important is re-establishing a straight line along he lower edge of the jawline. This also places the bone work sufficiently below the mental nerve foramen to avoid injury to it. Removing the irregular jawline section is best done with a reciprocating saw to provide a smooth cut.
The submental approach to straightening a ‘crooked’ jawline by an inferior border irregularity or reducing its vertical length is the one most effective approach. Its limitations is that it can not reach all the way back to the ramus or jaw angle area.
While a short chin is both common and easily treated by an implant or bony in most cases, the long or big chin is a much more challenging aesthetic issue. The tissue excess over the front end of the lower jaw makes its reduction fraught with problems of redundancy and potential tissue sag. Where does all the soft tissue go if the bone that is supporting it is reduced or removed?
It is these soft tissue considerations that make an intraoral approach for chin reduction usually problematic. While a pure vertical reduction can be done by a wedge removal bony genioplasty from an intraoral approach, burring reduction or reverse sliding genioplasties ‘create’ soft tissue excesses or tissue sagging. These ‘new’ soft tissue problems will mar any aesthetic change that the bone reduction has accomplished.
A submental approach to chin reduction offers dual management of bone and soft tissue excesses. Through an incision under the chin, the soft tissues are initially freed off of the bone. The chin bone can then be reduced in any dimension whether it is vertical, width or horizontal projection. Once the bone is reduced, the amount of soft tissue excess becomes apparent.
There are two types of soft tissues excesses created by a submental chin reduction. The first is the amount of skin, muscle and fat over the chin prominence that is removed by a submental excision and tuck. The second, which is most manifest in a vertical chin reduction, is the loss of the mandibular attachments to the infrahyoid musculature. If not resuspended there will be a resultant submental fullness due to muscle retraction.
Resuspension of the released anterior strap muscles is done through bone holes placed through the new lower edge of the chin bone. Reattaching this muscle helps tighten the submental area so that its contour fits better to the reduced chin without an abnormal bulge in the submental soft tissue triangle.
‘I got a chin reduction with an incision under the chin few months ago. I wanted to give an update. I think Dr Eppley was right about this approach. The chin is smaller. I think it could be a little bit smaller but I definitely think the procedure was worth it. The scar has gotten smaller and I hope it will completely resolve or at least become less noticeable. As always, I’m satisfied and happy with Dr Eppley’s work. Thanks a lot!‘
Reducing a large chin has historically been a difficult problem. Traditionally chin reductions were attempted from intraoral approaches, burring down the horizontal portion of the chin bone. While perhaps effective for a few macrogenia (large chin) patients with vertical bone excess (osteotomy with wedge bone removal), this approach is inadequate for most. Horizontal bone burring often left a soft tissue excess that subsequently sagged, creating the classic ‘witch’s chin’ deformity. For many large chins, the tissue problem is multidimensional and involves both bone and soft tissue. This is why a submental approach for most chin reductions offers a more effective solution. From underneath the bone of the chin can be both horizontally and vertically reduced if necessary as well as soft tissue excess removed and tightened. All tissues problems of the large chin can be simultaneously treated. This does result in a submental scar and keeping the length if the scar underneath the arc of the symphysis (curved chin bone) is crucial for a satisfying scar outcome.
It is very common that multiple procedures are done on the face at the same time. Whether it be for anti-aging effects or for reshaping a face, combinations of procedures produce more profound changes. This is because the face is made up of many different parts and making significant changes often requires altering more than one facial area.
The benefits of combination facial surgery are commonly seen in nose and chin surgery. Since the nose and chin make up the dominant structures of one’s facial profile, it is not surprise that the combination of rhinoplasty and chin augmentation have become known as a profileplasty. Profileplasty refers to any cosmetic procedure that would improve the appearance of the profile which is an aesthetic and proportionate relationship of the nose, chin and neck. Thus profileplasty is not just rhinoplasty and chin augmentation, although this is the most common one in the young, but also includes a facelift and chin augmentation which is most common in older patients.
It is easy to understand why rhinoplasty can be so important to profile changes as the nose sits at the center of the face. Even very subtle nose changes can be visually appreciated in the profile view. Lowering of the nasal bridge and reshaping the nasal tip in a large nose or augmenting the dorsal line and increasing tip projection in a smaller/flatter nose not only changes the shape of the nose but one’s profile as well.
Just like the nose the chin has an equal, if not greater, impact on one’s profile than even the nose. This is because the chin sits in the middle of the facial profile between the nose and the chin. Whether it is too small or too big, the chin influences the perception of both the nose and the neck. The nose, however, does not influence the appearance of the neck angle and a necklift does not alter the perception of one’s nose shape.
In many patients the best profile changes come from a change in the lower face. Chin surgery can improve facial proportion, creating a better balance between the upper face (forehead, nose and lips) and the neck. As a well known example, even a well shaped nose can seem larger if the face has a smaller chin. Even if some nose changes are done, the more important procedure might be chin augmentation on improving the appearance of the nose.
Chin surgery is often perceived as an augmentative operation but that is a limited view of the different types of available chin surgery. Chin augmentation historically is seen as an increased in horizontal projection, how much forward position of the chin is needed. While this can be done with either an implant to sit on top of the bone or to move the chin bone itself (sliding genioplasty), they change the shape of the chin differently. A chin implant can improve the horizontal projection of the chin but can do little for increasing the length or vertical height of the chin. Often more vertical height is needed when the chin is significantly short. Unlike a chin implant, a sliding genioplasty can not only bring the chin forward but can lengthen or shorten its vertical height as well.
While chin implants have historically lacked the ability for vertical elongation, new chin implants styles will soon be available that provide concurrent vertical lengthening as well. Rather than sitting completely on the bone, these newer designs sit on the ledge of the chin bone (halfway between the front and under edges of the chin bone) to create their effects.
While sliding genioplasties can lengthen the height of the chin, there are limits as to how much the bone can be moved forward. To keep the back of the moved chin bone in contact with the front edge of the fixed chin bone, the amount of bone advancement is usually limited to 10 to 12 mms. Very short chins often need much more than that to achieve an ideal chin position. In these cases a chin implant can be placed on top of the advanced chin bone (implant overlay) to achieve an additional 3mm to 5mms of further horizontal chin projection.
Chin reduction is not as commonly done for profile changes and has a checkered history. The most common chin reduction method is done as an intraoral burring or shaving of the front edge of the chin bone. While simple, it is rarely effective as no more than a few millimeters of bone is reduced and no change occurs in the soft tissue thickness. Often patients complain of seeing no change after this surgery and may even develop some soft tissue redundancy or sagging afterwards. The use of a reverse sliding genioplasty is also ill-advised as, while it does move the whole chin bone back, it pushes the attached soft tissues into the neck creating an undesired bulge.
The most effective chin reductions are done from a submental (under the chin) approach where the bone can be more dramatically reduced in all dimensions if needed and the excess soft tissues excised and tightened. (tucked) While this does create a scar under the chin, it can remain imperceptible if its length remains curved to parallel the shape of the jawline and it stays within the confines of a vertical line dropped down from the corners of the mouth.
When considering profileplasty, or even an isolated chin augmentation or reduction procedure, the use of computer imaging is critical. It can not only confirm which procedures are beneficial but, more importantly, the magnitude of those desired changes. A plastic surgeon can never really know what ‘flavor’ of change any patient desires and such imaging helps to establish what that is. While computer imaging is never a guarantee as to how the final result will look, it provides a method of visual communication to help the surgeon not guess as to the patient’s profileplasty goals.
Background: The chin is the prominent and most protruding structure of the lower face. It is a three-dimensional facial part that can have excesses and deficiencies of either the amount of projection, width or in its height. Because of the soft tissue that wraps around the chin bone, excessive or big chins pose greater aesthetic challenges than that of the small chin.
Having a big chin can involve any (or all) of the three dimensions and the surgical technique to reduce it varies based on these dimensions. In order of difficulty, the wide chin is the simplest to effectively change and the horizontal overprojecting chin can be the most challenging. The vertically long chin offers an intermediate level of difficulty, and like the chin that sticks out too far, the biggest challenge is how to predictably shrink the enveloping soft tissue to avoid a postoperative sag.
The vertically long chin can be reduced by two methods. The traditional approach is to use an intraoral osteotomy (genioplasty) and remove a wedge of bone either from above or below the osteotomy cut. The main advantage of this technique, besides the avoidance of an external scar, is that the soft tissue attachments to the underside of the chin bone are not disrupted. The alternative approach is to remove the bone from below through a submental incision, detaching and then reattaching the neck and chin soft tissues after the bone is removed. The advantage of this approach is that any redundant soft tissues of the chin can be directly removed and tightened and the superior attachments of the mentalis muscle is not disrupted.
Case Study: This 40 year-old female wanted a shorter and less long chin. She had a chin implant placed at the time of a previous rhinoplasty, at the suggestion of her surgeon, but it made her chin too big and it was subsequently removed. Despite its removal, she still wanted an even shorter chin. She acknowledged that she already had a small chin, by everyone else’s standards, but to her it was still too big. She just wanted the bottom part of it ‘cut off’.
Under general anesthesia, a 3.5 cm incision was made behind the submental skin crease. The soft tissue attachments to the bottom of the chin were detached and the exits of the menral nerves identified. A reciprocating saw was used to remove an 8mm segment of he bottom portion of the chin bone. The bone edges were smoothed with a rotating burr. Drill holes were made in the outer cortical edge of the chin and sutures were used to resuspend the strap muscles of the neck . Excess skin, fat and mentalis muscle was removed from the back side of the incision and the a layered soft tissue closure done, tucking it under the submental area.
Her postoperative course had the typical swelling which ensues with some expected temporary skin numbness. By 3 weeks after surgery, most of her swelling was gone but it took a full 6 weeks to see the final result and have all feeling return to normal. When seen at 3 months afetr surgery, she had a noticeable vertical chin reduction and no soft tissue tissue sag.
The submental ostectomy approach to vertical chin reduction is an effective alternative to the more traditional intraoral bony wedge resection approach. It may be the preferred approach when substantial soft tissue tightening is needed in addition to the bone reduction or a previous intraoral reduction procedure did not produce satisfactory results.
1) The length of the chin can be successfully reduced like other chin dimensions.
2) Vertical reduction of the chin can be done through either an intraoral wedge ostectomy/genioplasty or a submental ostectomy, of which the intraoral approach is the most common.
3) The submental vertical chin reduction removed the lower end of the chin bone as well as excises and resuspends the soft tissue chin pad and upper neck tissues.
Background:The chin is the dominant feature of the lower third of the face. When in good balance with the rest of the face it is an asset and a pleasing feature. When it is short or weak, it makes the face profile too convex and suggests a weak nature to the person. When it is too prominent, the facial profile becomes concave and makes the midface look retruded. Eitherway the chin plays a major role in facial appearance
Macrogenia, or overgrowth of the chin, creates a lower face that is out of balance with the upper and middle facial thirds. Most cases of macrogenia are a combination of excessive horizontal and vertical bone development. While macrogenia can be a reflection of an overall lower jaw overgrowth as evidenced by a Class III malocclusion, most larger chins occur in isolation. In women, the position of the chin should be slightly convex in profile and not too vertically long. Too much chin projection creates too strong of a lower face and a more masculine look.
Correction of a large chin is more complex and difficult than correction of an underdeveloped or small chin. While the bone reduction is fairly straightforward, whether by osteotomy or burring reduction, management of the excess soft tissues is another matter.In small chin reductions, the soft tissue will shrink and adapt to the new bone shape. But in large chin reductions, the soft tissues will not shrink enough and will sag if not removed or tightened. This can create the classic ‘witch’s chin deformity’.
Case Study: This 33 year-old female felt her chin was too big and wanted it reduced. She had a slightly concave facial profile, a vertically long chin, and a normal occlusion. In doing an imaging analysis based on photographs, the amount of chin reduction needed was a minimum of 8mm horizontal reduction and a 6mm vertical reduction. This amount of bony movement was felt to be too much for an intraoral osteotomy in which the soft tissues would only bunch up with the backward or reverse sliding genioplasty.
Under general anesthesia, a submental approach to her chin reduction was done. Through a curved 4 cm skin incision, the chin bone was widely exposed. A fine burr was initially used to make a deep vertical bone cut in the midline down through the outer cortex of 8mms in depth. A burr was then used to remove the side portions of the remaining chin bone down to the same level and tapering it into the prejowl area. From the inferior edge, the chin bone was burred down 6mms. A wedge of skin, muscle and fat was removed from the front edge of the incision and the muscle layer was then put back together and tightened over the lower edge of the reshaped chin bone. The skin was then closed and a tape dressing and ice pack applied.
She had a fair amount of chin swelling after surgery that took three weeks before any amount of chin reduction could be appreciated. After three months, a very evident reduction in the size of the chin would be appreciated.
Of the two methods for chin reduction, the submental approach is the most versatile. It allows not only for better bony chin reshaping but permits soft tissue reduction and tightening as well. Failure of the soft tissues to adhere tightly to the new reduced bony chin shape will result in an unsightly soft tissue sag.
1) A large and prominent chin consist of both excess bone and soft tissue. Both must be managed for a successful chin reduction procedure.
2) Most chin reductions are best done from a submental approach where the bone can be reduced in all dimensions and the soft tissues tightened.
Dr. Barry Eppley is an extensively trained plastic and cosmetic surgeon with more than 20 years of surgical experience. He is both a licensed physician and dentist as well as double board-certified in both Plastic and Reconstructive Surgery and Oral and Maxillofacial Surgery. This training allows him to perform the most complex surgical procedures from cosmetic changes to the face and body to craniofacial surgery. Dr. Eppley has made extensive contributions to plastic surgery starting with the development of several advanced surgical techniques. He is a revered author, lecturer and educator in the field of plastic and cosmetic surgery.