Orthognathic Surgery
 |  |  |
Relationship between mandible and maxilla
Orthognathic Surgery is surgery to correct conditions of the jaw and face related to structure, growth, sleep apnea, TMJ disorders, correct malocclusion problems owing to skeletal disharmonies or other orthodontic problems that cannot be easily treated with braces. Bones can be cut and re-aligned, held in place with either screws or plates and screws.Indications
- Gross jaws discrepancies (Anteroposterior , Vertical and /or Transverse discrepancies)
- Facial skeletal discrepancies associated with documented sleep apnea, airway defects, and soft tissue discrepancies.
- Facial skeletal discrepancies associated with documented temporomandibular joint pathology.
Surgeon
Orthognathic Surgery is performed by either an oral and maxillofacial surgeon or a craniofacial surgeon in collaboration with an orthodontist, often including braces before and after surgery, and retainers after the final removal of braces. Orthognathic surgery is often needed after reconstruction of cleft palate or other major craniofacial anomalies. Careful coordination between the surgeon and orthodontist is essential to ensure that the teeth will fit correctly after the surgery. This coordination often necessitates that the surgeon be trained in dentistry, where complex concepts of occlusion between upper and lower teeth are taught. Unlike Oral and Maxillofacial Surgeons who are trained in dentistry, Plastic Surgeons receive no or minimal training. Thus, it is rare that an Orthodontist would find it appropriate for the surgery to be referred to a non-Oral and Maxillofacial Surgeon.Planning
Planning for the surgery usually involves input from a multidisciplinary team. Involved professionals are Oral and Maxillofacial surgeons, Orthodontists, and sometimes a Speech and language therapist. As the surgery usually results in a noticeable change in the patient's face a psychological assessment is occasionally required to assess patient's need for surgery and its predicted effect on the patient.Radiographs and photographs are taken to help in the planning and there is software to predict the shape of the patient's face after surgery,which is useful both for planning and for explaining the surgery to the patient and the patient's family. Advanced software can allow the patient to see the predicted results of the surgery.
The main goals of orthognathic surgery are to achieve a correct bite, an aesthetic face and an enlarged airway. While correcting the bite is important, if the face is not considered the resulting bony changes might lead to an unaesthetic result. Orthognathic surgery is also available as a very successful treatment (90-100%) for obstructive sleep apnea. Great care needs to be taken during the planning phase to maximize airway patency.
Procedure
The surgery might involve one jaw or two jaws during the same procedure. The modification is done by making cuts in the bones of the mandible and / or maxilla and repositioning the cut pieces in the desired alignment. Usually surgery is performed under general anaesthetic and using nasal tube for intubation rather than the more commonly used oral tube; this is to allow wiring the teeth together during surgery. The surgery often does not involve cutting the skin, and instead, the surgeon is often able to go through the inside of the mouth.Cutting the bone is called osteotomy and in case of performing the surgery on the two jaws at the same time it is called a bi-maxillary osteotomy (two jaws bone cutting) or a maxillomandibular advancement. The bone cutting is traditionally done using special electrical saws and burs, and manual chisels. Recently a machine that can make the bone cuts using ultra-sound waves has been introduced; this is yet to be used on a wide scale. The maxilla can be adjusted using a "Lefort I" level osteotomy (most common). Sometimes the midface can be mobilised as well by using a Lefort II, or Lefort III osteotomy. These techniques are utilized extensively for children suffering from certain craniofacial abnormalities such as Crouzon syndrome.
The jaws will be wired together (inter-maxillary fixation) using stainless steel wires during the surgery to ensure the correct re-positioning of the bones. This in most cases is released before the patient wakes up. Some surgeons prefer to wire the jaws shut.
Complications
Like any other surgery, there can be some complications like bleeding, swelling, infection, nausea and vomiting. There could also be some numbness in the face due to nerve damage. The numbness may be either temporary, or, more rarely, permanent. In general, complications of this surgery occur, but not frequently.If the surgery involves the upper jaw, then the surgery could have an effect on the shape of the patient's nose. This can be minimised by careful planning and accurate execution of the surgical plan. Sometimes, this is considered part of the benefit.
Post operation
After orthognathic surgery, patients are often required to adhere to an all-liquid diet. After time, soft food can be introduced, and then hard food. Diet is very important after the surgery, to accelerate the healing process. Weight loss due to lack of appetite and the liquid diet is common, but should be avoided if possible. Normal recovery time can range from a few weeks for minor surgery, to up to a year for more complicated surgery.For some surgeries, pain may be minimal due to minor nerve damage and lack of feeling. Doctors will prescribe pain medication and prophylactic antibiotics to the patient. Most of the swelling will disappear in the first few weeks, but some may remain for a few months.
The surgeon will see the patient for check-ups frequently, to check on the healing, check for infection, and to make sure nothing has moved. The frequency of visits will decrease over time. If the surgeon is unsatisfied with the way the bone is mending, he may recommend additional surgery to rectify whatever may have shifted. It is very important to avoid any chewing until the surgeon is satisfied with the healing.
Jaw Reduction Surgery
Jaw reduction is a type of aesthetic plastic surgery in which the objective of treatment is 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.
Facial aesthetics
A square lower jaw is generally considered a very masculine trait. Widening of the lower third of the face can cause either a square appearance to the face as a whole or can distort the natural appearance of the angle between the chin and the neck.Whereas square lower jaws are often considered a positive trait in Caucasian and many Asian men, a wide mandible can cause significant facial discordance and/or masculinization of the female face-particularly in those of East Asian descent. Even in certain men, the size of the lower jaw can cause facial disharmony-particularly when there is asymmetry.
A wide lower face can primarily be caused by enlargement of the mandible or masseter muscle.
Causes
The primary cause of an enlarged mandible is developmental or congenital. There are some rare disorders that can further widen the jaw such as acromegaly.Conversely, while a masseter muscle can be large due to congenital reasons, it can commonly be an acquired deformity. Like any muscle it increases in size with exercise. Behaviors such as repeated gum chewing, teeth clenching, or bruxism can contribute to enlargement of the muscle.
Techniques
There are several jaw reduction techniques available - both surgical and non-surgical. Ideally prior to selection of a treatment, the patient is examined to determine whether the cause is due to the bone, the masseter or both. Additionally, if a treatable cause is present it should be identified.Surgical reduction
Surgical techniques are used to directly reduce the size of an enlarged mandible. Incision can be to the inside or outside of the mouth, though the internal incision is the most common because it leaves no visible scar. A bur is used to remove the outer layer of the enlarged mandible, narrowing the jawPotential complications include injury to the inferior alveolar nerve which provides sensation to the lower lips and teeth.
Distraction Osteogenesis in Maxillofacial
Maxillofacial Surgeons use this technique for the correction of micrognathia, midface, and fronto-orbital hypoplasia in patients with craniofacial deformities.
Correcting the majority of congenital craniofacial defects, as well as
some facial injuries resulting from trauma, requires making bones
longer. Distraction osteogenesis is an effective way to grow new bone,
but it is much more difficult to accomplish in the face than in other
areas of the body. Bones must often be moved in three dimensions, as
opposed to just one, as in a limb, and scarring must be kept to a
minimum. Researchers are attempting to improve the distraction devices
used in the face. Until recently, the mechanisms were external and only
operated along straight lines. Now, maxillofacial surgeons can use
curvilinear devices capable of moving bone in three dimensions.These new devices still need to be improved. They depend on patient caretakers reliably turning a screw. The next goal is to create devices that will move bone continuously, in daily increments of 1 mm. These continuously moving devices would cause less pain, wouldn't require daily patient compliance, and might promote faster bone growth. At the moment, researchers are testing a continuously moving device in animal models, and they have found that the device's components are durable, that its user interface works, and that it is tolerated by the body. When the position sensor in the device is perfected, the device will be ready to use in people.
In distraction osteogenesis procedures involving the face, it is critical that bone movements be carefully planned before a device is implanted. No existing device is capable of changing its trajectory mid-course, and small skeletal changes lead to large changes in the structure of the face. Recently researchers have developed state-of-the-art software capable of simulating the entire process of distraction osteogenesis. The 3-D planning tool uses data from CT scans to create a segmented model of the patient's skull, and it then calculates the vector of movement required to achieve desirable bone positioning. Outcome of CT scans can be overlaid on the original model to assess the effectiveness of the procedure. In the future, researchers hope that the distraction devices used in maxillofacial procedures will continue to improve, along with the corresponding software.
RESULTS: All patients achieved lengthening of their jaws. However, premature consolidation was noted in two patients, and one patient had significant relapse.
Genioplasty Chin Surgery
Genioplasty (Mentoplasty) Malar Augmentation Or Reduction (Chin Surgery)The chin provides harmony and character to the face. A strong chin or prominent jaw line is considered to be aesthetically pleasing, especially in males. When chin surgery is indicated, whether by anterior horizontal mandibular osteotomy (AHMO) or by alloplastic implant augmentation, it can create an aesthetically pleasing facial contour and establish proportionate facial height. In addition, the AHMO can improve obstructive sleep apnea by elevating the hyoid bone.
Most genioplasty procedures are done to improve the mandibular profile in order to obtain a more natural profile. Genioplasty can shorten or lengthen the lower third of the face. Facial asymmetry may be corrected by rotation of the chin-point to coincide with the midline. The advantages of osseous genioplasty are versatility, reliability and consistency in correcting problems in the sagittal and vertical planes to achieve greater chin projection. In order to be able to make an appropriate recommendation, the correct preoperative workup should be performed, including soft and hard tissue analyses. Ideally, cephalometrics and video cephalometric predictions would also be performed.
Anatomy and Analyses
It is important for the surgeon to be familiar with the classic soft tissue analysis and diagram of facial proportions. The size, shape and position of soft and hard tissue can enhance facial harmony and symmetry. The relationship between soft tissue and bone is important for planning the bony chin correction. For chin advancement, the bone to soft tissue proportion is 1:0.8, meaning that 1 mm of bony change is associated with 0.8 mm of soft tissue change.The face can be divided into upper, middle and lower thirds. The upper third of the face spans from the hairline to the glabella; the middle third from glabella to subnasale; and the lower third from subnasale to menton. The lower third of the face can be further divided into an upper half (Sn to vermilion of the lower lip) and a lower half (Me to vermilion of the lower lip). The face is "balanced" when the three thirds are of similar height. Cephalometric analysis ensures that skeletal and occlusal disparities are identified and can be corrected before or at the same time as a genioplasty.
Many patients that complain of a small chin truly do not have microgenia.
They often have a true deficit of the mandible in the sagittal plane, which can be a class 2 malocclusion (retrognathia) or normo-occlusion (retrogenia). Retrognathia is ideally corrected with a bilateral sagittal split osteotomy (BSSO); however if the discrepancy is small, advancement genioplasty may sufficiently camouflage the facial profile into an orthognathic appearance. Retrogenia (chin point deficiency in the setting of a class I occlusion) and mild retrognathia (<3 mm) are ideal cases for a genioplasty. It is important to understand the relationship of the dentition to the chin point. The boney chin point should be about 2 mm posterior to the labial surface of the mandibular incisors. This will help maintain a natural labiomental fold.
The position of the labiomental angle is paramount and profoundly influences the aesthetic outcome.
Cephalometric analysis helps the surgeon to plan the operative procedure. The treatment plan is based on incorporation of these data into clinical assessment that will facilitate a postsurgical profile that is esthetically pleasing.
Perceived Chin Abnormalities Due to Anomalies of The Maxilla
When facial analysis identifies disharmony within a patient's profile, the surgeon must determine whether there is an underlying occlusal and skeletal deformity or merely a poorly or over-projected mentum. True maxillomandibular discrepancies should be addressed with orthognathic surgery.In the case where occlusion is stable and a small mandibular deficiency exists (retrogenia), an isolated mandibular sagittal deficiency may be a candidate for an AHMO.
To highlight the importance of the correct diagnosis, one can take the common occurrence of a patient complaining of a "small chin." A recessed chin may be retrogenia or microgenia. An over projected chin may be macrogenia or prognathia. Micrognathia and macrognathia are rare. Prognathia and retrognathia more commonly contribute to chin point abnormalities.
In the setting of a patient complaining of a small chin, the lateral profile should be evaluated. Concavity or convexity in conjunction with the proportions of the middle and lower third of the face should be considered in the planning. The maxilla should be evaluated. If the maxilla is set appropriately in the sagittal plane and there is mild retrognathia (<3 mm) or retrogenia, then a genioplasty is appropriate. However, if a maxillary developmental dysplasia is present, a formal orthognathic work-up should be done.
In contrast, patients complaining of a "prominent chin" often have pseudomacrogenia. These individuals may have maxillary sagittal hypoplasia, which manifests with a retruded upper lip, a midfacial concavity or deficiency, and a chin that may appear prominent in the sagittal plane. Since the true etiology is maxillary hypoplasia, the corrective procedure would be a Le Fort I osteotomy to advance the maxilla anteriorly to coincide with the chin point. A pitfall would be for a novice surgeon to perform a genioplasty to set the chin point back to coincide with the maxilla.
In maxillary vertical deficiency, the patient presents with pseudomacrogenia due to the counterclockwise rotation of the mandible. In this case, the chin is accentuated and appears larger than normal. Patients with this condition have a short lower third facial height and present with poor maxillary tooth show at rest and when smiling. When the mandible is placed in the normal centric relation, the chin point increases in the sagittal plane. Maxillary vertical height correction will allow for a more natural position of the chin and only then can a decision be made on the need for genioplasty.
Maxillary vertical excess may manifest as pseudomicrogenia due to the excessive downward growth of the maxilla causing a clockwise rotation of the mandible. In such cases, the rotation of the mandible results in the appearance of a small chin due to poor projection of the chin in the sagittal plane. The patient will likely have excess gingival show, a long lower third facial height and mentalis muscle strain from the forces needed to close the interlabial gap. The treatment for this type of facial anomaly may be to reposition the maxilla superiorly, particularly in the posterior area.
Maxillary sagittal hyperplasia is extremely rare. Patients may complain of a small chin as well. Once again, this is most likely a case of pseudomicrogenia, where the chin appears relatively small due to the prominence of the maxilla in the sagittal plane. These patients will have a convex facial profile associated with maxillary protrusion and an acute nasolabial angle. This form of microgenia can be corrected with repositioning of the maxilla, after which a decision can be made on the need for an adjunct genioplasty.
Evaluation of The Mandible
After a thorough investigation to rule out any maxillary discrepancies, the next step is to evaluate the mandible. For a patient with mandibular hypoplasia with either gross malocclusion or severe hypoplasia (greater than 4 mm), a formal orthognathic work-up is necessary. The risks of advancing or augmenting a chin greater than 5-6 mm include an unnatural appearance, a deep labiomental angle, and the risk of advancing the chin point past the lower central incisor. Severe mandibular sagittal hypoplasia is corrected with a BSSO, and genioplasty should be viewed as an adjunct procedure. Prognathia in the setting of class 3 malocclusion should be corrected by a setback with a BSSO. Isolated true macrogenia in the presence of a normal class 1 occlusion can easily be treated with a genioplasty, setting the chin point back and even reducing chin height if needed.Indications for Isolated Genioplasty (Mentoplasty)
After careful scrutiny of the skeletal, dental and soft tissue structures, there exist certain cases that are amenable to isolated genioplasty. An isolated genioplasty can be considered if functional occlusion is present and the lower third profile has mild hypoplasia or hyperplasia in the sagittal or vertical plane. A sagittal hypoplasia (3-4 mm) in the setting of functional normo-occlusion with acceptable facial proportions is an ideal candidate for AHMO with advancement. A variation of the standard sliding genioplasty is the "jumping" genioplasty. The "jumping" genioplasty is ideal for sagittal advancement when vertical reduction is needed.Patients who are considered for isolated genioplasty should have a good overall profile and occlusion. The surgical goals for these patients include creating an aesthetically pleasing facial contour and establishing proportionate facial height. Ideal candidates for a genioplasty are: (1) retrogenia, i.e., recessed chin point with class I occlusion; (2) mild retrognathia (<4 mm) with a functional occlusion; and macrogenia.
For example, in a patient that may have a long lower third of the face, a reduction genioplasty is performed to reduce the vertical dimension of the chin. Vertical reduction is done by performing a second horizontal osteotomy that is parallel to the first osteotomy, and a segment of bone is removed. Another indication for an isolated genioplasty may be a mild asymmetry, when the chin does not coincide with facial midline. An oblique triangular wedge of bone can be removed from one side and transplanted to the other side to correct chin asymmetry.
In all cases, the chin has to be rigidly fixed by miniplates, wire or screws. A variety of genioplasty is the "jumping" genioplasty. This type of procedure allows the surgeon to both increase the chin projection and shorten the vertical dimension of the chin simultaneously. After the osteotomy is completed, the basilar segment is elevated on top of the upper symphysis.
Genioplasty - Surgical Technique - Procedure
Genioplasty can be performed under local anesthesia with IV sedation or under general anesthesia. General anesthesia is more commonly used with this procedure.Lidocaine with epinephrine is infiltrated along the depth of the buccal vestibule. An incision is made in the buccal vestibule, initially perpendicular to the mucosa then perpendicularly to the muscle and bone. The dissection is continued in the subperiosteal plane to identify the mental foramen on both sides. After identification of the mental foramen, the mental nerves should be protected from both direct and traction injury.
The osteotomy is done under the apices of the teeth and the mental nerve. Upon completion of the osteotomy, the chin is then rigidly fixated. A step-off (sharp edge) at the posterior part of the genioplasty should be avoided. The contour of the mandible should be smooth. There are a variety of techniques used for fixation of the chin including wires, resorbable or titanium bone plates. Closure should be done in multiple layers. The mentalis muscle must be reapproximated.
The muscle layer can also be reattached to the chin using Mitek anchors. We prefer using two Mitek anchors to secure the mentalis muscle to bone. Alternatively, simple reapproximation with two horizontal mattress sutures is acceptable. This prevents ptosis of the mentalis muscle. Nonfixation may result in a "witches chin." A compressive chin dressing is worn for 5 days postoperatively. The oral mucosa is closed with a running 3-0 chromic suture.
The advantage of this procedure is its versatility, reliability and reproducible correction of chin point discrepencies. The disadvantages, when compared to alloplastic augmentation, include increased operative time, bleeding and incidence of mental nerve hypoesthesia.
Lip Debulking
Plastic Cosmetic Surgery for the Lips
Are your lips too thick, or is the red of your lips too small? Lip enhancement or lip reduction . Is your upper lip too big or is your bottom lip too big, does it hang down? A cosmetic procedure or plastic surgery may be able to help make your lips more beautiful and give you more self-confidence.Possible surgical treatments:
- Lip Plasty: to make the lips narrower or fuller.
- Lifting the upper lip: shortening a drooping upper lip
- Upper lip correction: gum - smile.
Standard result for lip reduction
Lip-Plasty: reducing the size of thick lips- Are your lips too big? It is possible to reduce their size.
Surgical procedures
- LIP-PLASTY: Are your lips too thick or is the red of your lips too small? If so you could consider plastic surgery correction to make your lips smaller or fuller.
- LIFTING THE UPPER LIP: with age the upper lip tends to droop and the red of the lips becomes narrower. This symptom of the aging process can be corrected with a simple "butterfly correction".
- GUMMY SMILE CORRECTION: if your gums are exposed because your upper lip is lifted too high when you smile, this procedure can offer a solution.
Lip-Plasty
Lip reduction:
Are your lips too thick or too full? It is possible to reduce the size of your lips.Through a small incision the plastic surgeon turns the excess red of the lips inwards. The scar is hidden in the mouth and is therefore invisible.
This procedure is performed under a local anaesthetic and last about an hour. The lips will be swollen and bruised for about 2 weeks. After 6 weeks the definite result is visible.
Lip augmentation:
Are your lips too thin or is the red part of the lips too narrow? It is possible to enhance the lips.If an injection is not effective because the red of the lips is too inverted then it can be enlarged by turning the red of the lips from the inside of the lips outwards.
This procedure is performed with a local anaesthetic and lasts about an hour. The lips may be swollen and bruised for about two weeks. This procedure can be combined with an injectable filler.
Lip-Plasty recovery:
You have to wait a few months before the scars from a Lip-Plasty fully mature. You may experience a little discomfort when moving the lips for a few weeks. A temporary loss of sensation in the lips is possible. Sometimes the scar tissue can remain lumpy and sensitive for a longer period.Lifting the upper lip:
Lip Lift
The plastic surgeon usually makes a small butterfly-shaped incision. The scar is hidden in the nostrils. Lifting the upper lip gives a more youthful appearance. The procedure is performed with a local anaesthetic and takes about half an hour.
Lifting the upper lip: for a younger look.
- Lifting the upper lip
- Filling the lips.
Lips: Book your consultation
During your no-obligation consultation all aspects of any possible treatment will be discussed: the doctor will make a detailed assessment of your wishes and requirements and will determine whether you are a good candidate for lip correction. The doctor will discuss the expected results with you as well as any possible risks the treatment involves and the necessary aftercare.Cleft Lip and Palate
Cleft Lip (Cheiloschisis) and Cleft Palate (Palatoschisis), which can also occur together as cleft lip and palate, are variations of a type of clefting congenital deformity caused by abnormal facial development during gestation. A cleft is a fissure or opening - a gap. It is the non-fusion of the body's natural structures that form before birth. Approximately 1 in 700 children born have a cleft lip and/or a cleft palate. An older term is harelip, based on the similarity to the cleft in the lip of a hare.A cleft lip or palate can be successfully treated with surgery, especially so if conducted soon after birth or in early childhood.
If the cleft does not affect the palate structure of the mouth it is referred to as cleft lip. Cleft lip is formed in the top of the lip as either a small gap or an indentation in the lip (partial or incomplete cleft) or it continues into the nose (complete cleft). Lip cleft can occur as a one sided (unilateral) or two sided (bilateral). It is due to the failure of fusion of the maxillary and medial nasal processes (formation of the primary palate).
Cleft palate
Cleft palate is a condition in which the two plates of the skull that form the hard palate (roof of the mouth) are not completely joined. The soft palate is in these cases cleft as well. In most cases, cleft lip is also present.Palate cleft can occur as complete (soft and hard palate, possibly including a gap in the jaw) or incomplete (a 'hole' in the roof of the mouth, usually as a cleft soft palate). When cleft palate occurs, the uvula is usually split. It occurs due to the failure of fusion of the lateral palatine processes, the nasal septum, and/or the median palatine processes (formation of the secondary palate).
The hole in the roof of the mouth caused by a cleft connects the mouth directly to the nasal cavity.
Note: the next images show the roof of the mouth. The top shows the nose, the lips are colored pink. For clarity the images depict a toothless infant.
Cleft lip treatment
Within the first 2-3 months after birth, surgery is performed to close the cleft lip. While surgery to repair a cleft lip can be performed soon after birth, often the preferred age is at approximately 10 weeks of age, following the "rule of 10s" coined by surgeons Wilhelmmesen and Musgrave in 1969 (the child is at least 10 weeks of age; weighs at least 10 pounds, and has at least 10g hemoglobin). If the cleft is bilateral and extensive, two surgeries may be required to close the cleft, one side first, and the second side a few weeks later. Often an incomplete cleft lip requires the same surgery as complete cleft. This is done for two reasons.Firstly the group of muscles required to purse the lips run through the upper lip. In order to restore the complete group a full incision must be made. Secondly, to create a less obvious scar the surgeon tries to line up the scar with the natural lines in the upper lip (such as the edges of the philtrum) and tuck away stitches as far up the nose as possible. Incomplete cleft gives the surgeon more tissue to work with, creating a more supple and natural-looking upper lip.
Cleft palate treatment
Often a cleft palate is temporarily closed, the cleft isn't closed, but it is covered by a palatal obturator (a prosthetic device made to fit the roof of the mouth covering the gap).Cleft palate can also be corrected by surgery, usually performed between 6 and 12 months. Approximately 20-25% only require one palatal surgery to achieve a competent velopharyngeal valve capable of producing normal, non-hypernasal speech. However, combinations of surgical methods and repeated surgeries are often necessary as the child grows. One of the new innovations of cleft lip and cleft palate repair is the Latham appliance. The Latham is surgically inserted by use of pins during the child's 4th or 5th month. After it is in place, the doctor, or parents, turn a screw daily to bring the cleft together to assist with future lip and/or palate repair.
If the cleft extends into the maxillary alveolar ridge, the gap is usually corrected by filling the gap with bone tissue. The bone tissue can be acquired from the patients own chin, rib or hip.
For further information and appointment please contact 91-939 44 44 113 on all working days between 9.30 AM and 8:00 PM
No comments:
Post a Comment