 Today's topic is anterior maxillary osteotomy. In the previous lecture we have seen various indications of Lefort 1 osteotomy and the use of Lefort 1 osteotomy is so wide that it has limited the indications of anterior maxillary osteotomy. Let's see where all the anterior maxillary osteotomy indicated. Mainly as its name suggests this technique is performed in the anterior maxilla or the premaxilla. This technique can be used to resolve any isolated anterior open bite or bimaxillary protrusion in the anterior maxilla. Any excess in the vertical or anterior posterior dimensions can be corrected provided the posterior occlusion is acceptable. This is a good option to perform to correct any marked protrusion of maxillary teeth. Those patients are not cooperative towards orthodontic treatment. And when orthodontic tooth movement is inadvisable because of pre-existent pathology throat resorption or ankylosis anterior maxillary osteotomy is a good option to consider. Now similar to the Lefort 1 osteotomy the segmentalized anterior maxilla will survive opponent's blood supply through a soft tissue pedicle. There are various studies that indicate that any variation in the flap design doesn't affect the postoperative blood supply to the anterior maxillary segment. Therefore many different surgical incisions have been described for access during anterior maxillary osteotomy and the blood supply to the maxillary segment can be maintained by a labial buckle or palatal pedicles individually or in a combination. So with this in mind the three common AMO techniques generally considered are the wound technique, Weisman technique and cluper techniques. Each of the techniques will be explained in detail. Let's move on to it. Before discussing each technique in detail let's have a general understanding of how the anterior maxillary osteotomy is performed. Anterior maxilla can be mobilized with two vertical buckle osteotomies, one horizontal osteotomy and transpiratal osteotomies. One vertical buckle osteotomy is performed on each side of the maxilla through the extraction socket of the first premolar. This is the vertical osteotomy. This is followed by a horizontal osteotomy which is nothing but a medial extension of the vertical osteotomy towards the piriform fossa on either side. The third osteotomy is a transpiratal osteotomy that means osteotomy across the palate at the first premolar region. These are the three basic osteotomies performed in AMO. Coming to the first technique of AMO which is the Woundwork method. In Woundwork method the buckle pedicle is preserved or the maxilla the segmentalized anterior maxilla is preserved with a buckle pedicle. It is maintained with the buckle pedicle. This is very important to remember. How is this technique performed? This is usually performed under general anesthesia. Once the patient is prepared and positioned local anesthetic solution is injected into the upper buckle vestibule. Three incisions are used in this particular technique. There are two vertical incisions and one transpiratal incision. The two vertical incisions are carried out just distilled to the first premolar that is here. This is where the vertical incision is given on either side. So what you have to keep in mind while placing an incision is that the incision should be placed at such a point that it lies on healthy bone once the incision is closed. After the wound is closed the suture line should be over the healthy bone not at the osteotomies side. So keep that in mind while placing an incision. Once the incisions are given extraction of the first premolar is carried out on both the sides. Following this you give your first vertical osteotomy and you remove the desired amount of bone required for the setback of anterior maxillary segment. On either side you remove the desired amount of bone after performing a vertical osteotomy. The vertical osteotomy has a medial extension that forms the horizontal osteotomy towards the piriform region. This is a horizontal osteotomy performed through subperiosteal tunneling. Through both the vertical incisions you perform the horizontal osteotomy beneath the periosteum. So you do not give a separate incision or an opening in the anterior maxilla you perform a subperiosteal tunneling osteotomy towards the piriform region. This is followed by a transpalatal osteotomy across the palate at the first premolar side. In this diagram what is marked in white is the palatal osteotomy. So once all the three osteotomies are performed you need to separate the nasal septum from maxillary segment. This is performed with a superior fracture of the anterior maxillary segment. You gently out fracture the anterior maxilla and separate it from the nasal septum. So this is the basic procedure carried out for a view under a technique of AMO. Let's see it once again. There are three incisions in total, two vertical and one palatal incision. This is followed by buckled vertical osteotomy through the extraction site of the first premolar. This is extended horizontally towards the piriform aperture followed by a transpalatal osteotomy. Once all the three osteotomies are performed premaxilla is fractured using finger pressure in a superior direction. After the fracture of premaxilla the nasal aspect of the palate or the fracture premaxilla can be trimmed using a bone launcher. Remove any bone protrusions or irregularities and do a good filing which will facilitate a very efficient setback. Once this step is over you perform a intermaxillary fixation and stabilize the anterior segment using bone plates at the piriform region. This is how a wound liver AMO is performed and the most important thing to be remembered is that the anterior maxillary segment is preserved with a buckled pedicle. So this is about view under a method. The second anterior maxillary osteotomy technique is the Wassman which preserves both the buckle and palatal soft tissue pedicles unlike the view under a method where only the buckle pedicle is preserved. That is however more difficult to gain access to the palatal aspect of the anterior maxilla with this kind of incision. There are three incisions all the three are vertical incisions placed on the buckle aspect. Two vertical incisions are made at the extraction site of the first premolar or at the intended osteotomy sites. A third midline incision is given to gain access towards the anterior nasal spine. Through this anterior incision it is possible to elevate and protect the nasal flow and to separate the nasal septum from the maxillary crest. So there are three vertical incisions placed. After the incisions are given the buckle vertical osteotomy is performed at the extraction site of first premolars on either side similar to that of view under a technique. Vertical osteotomy is performed and the buckle horizontal osteotomy is created by tunneling through the anterior and posterior buckle incisions. As already explained in the view under a technique there is a horizontal osteotomy which is nothing but a medial extension of the vertical osteotomy. This is performed subperiostally between the anterior and posterior incisions. Following horizontal osteotomy the transpalital osteotomy is created. You know there is no transpalital incision. So how is the transpalital osteotomy performed? It is performed through the buckle vertical osteotomy on either side. This created through the buckle vertical osteotomy on either side by maintaining a digital palpation of the palatal mucosa. While performing the palatal osteotomy place your index finger at the palatal mucosa just to ensure that the palatal tissues are not traumatized during the procedure. There is no direct access to the palatal bone hence keep a palpating finger at the palatal mucosa just to ensure its safety. Now the transpalital osteotomy may be also facilitated by use of a mid palatal sagittal incision. As seen in this diagram just to facilitate the procedure you may place a vertical incision. Not a horizontal incision you place a vertical incision just to gain direct access to the thick bone of the mid palette. These are the three osteotomies performed. Two vertical osteotomies, one buckle horizontal osteotomy through subperiostal tunneling and a palatal osteotomy as an extension of the buckle vertical osteotomy. Taking care not to damage the palatal tissues. Once the osteotomies are performed the anterior maxillary dentorchial segment can be repositioned. Similar to the Woundover technique explained once the osteotomies are completed the pre maxilla is fracture placed in intermaxillary fixation and then stabilized using bone plates. So this is regarding wasment method of anterior maxillary osteotomy. Moving on the third anterior maxillary osteotomy technique is the Kuiper technique which is a minor version of total maxillary osteotomy down fracture. In this technique the palatal pedicle is kept intact which ensures re-vascularization of the segmentalized anterior maxilla. A buckle vertical incision is created 4 to 5 mm above the muco gingival junction extending from the zygomatico maxillary buttress on one side to the other. Full thickness mucoperiostal flap is raised exposing the anterior lateral maxillary walls, the pyreform aperture, the nasal floor and the nasal septum. In this technique the sequence of osteotomies is operator dependent but the general procedure involves completion of the vertical buckle and horizontal osteotomies under direct visualization. Prior to performing an osteotomy the nasal mucosa is elevated from the superior surface of maxilla. It is easier to complete the osteotomies if the nasal septum is first released from the maxillary crest. The horizontal osteotomy is then completed. It extends from first premolar on one side to the other. The buckle horizontal osteotomy extends from one premolar to the other and this is followed by down fracture of the anterior maxilla using digital pressure inferiorly. This is similar to the Lefort 1 osteotomy technique. Once down fracture is performed you carry out the vertical osteotomy bilaterally. This is done through the extraction socket of first premolar on both sides. Next you perform the transpalatal osteotomy. So before placing an osteotomy cut on the palate similar to the Wassman technique a finger is placed on the palatal mucosa to palpate the osteotomy to prevent any tissue damage as the osteotomy is advanced. So the transpalatal osteotomy is then completed under direct visualization from above. That is from here you have a direct access to the palate and under direct visualization the transpalatal osteotomy is carried out. This also allows good access to the nasal crest of maxilla and the mid palatal bone for osceous reconferring. As it was done in Lefort osteotomy for superior repositioning of maxilla osceous reconferring this area is required. So once osceous reconferring is done the maxilla is repositioned and placed in IMF. Following IMF stabilization of the repositioned maxilla may be completed with bone plates or wires. So this is the technique of anterior maxillary osteotomy cuper method. What is the advantage of cuper method over the other two techniques? There is direct access to nasal structures because we are performing a down fracture here you have direct access to the nasal structures as well as direct visualization of the palate to carry out a transpalatal osteotomy. Also the pedicle we preserved is the palatal one which supplies vasculature to the segmentalized maxilla. The fixation also is easier in this technique. So this is regarding anterior maxillary osteotomy. Thank you.