**3. Paranasal modification**

**Figure 5.** A simple geometric calculation allows one to mobilize the chin in a vertical, horizontal andsagittal direction, according to the needs of each patient the design of the planed osteotomy can be trace on the tracing paper and a sur‐

**Figure 6.** A 29 years old man who underwent zigzag genioplasty(type III) in combination with rhinoplasty,buccal fat pad lifting[48],malar prosthesis and paranasal augmentation.a,b,c,d) Incision of the oral mucosa was performed 5 to 7 mm labial to the depth of the vestibule and directed horizontally. Then, the muco-periosteal flap was released, and the mental nerve was exposed. The chin prominence was degloved, and the lingual muscle attachments were maintained for blood supply. The osteotomy sites (type III) were marked with a surgical marker and the ostectomy was done with reciprocal saw and fissure bur In the next step, bone strips were removed bilaterally and the osteotomy was continued

gical guide can be made simply.

164 A Textbook of Advanced Oral and Maxillofacial Surgery Volume 2

**Clinical evaluation**: There is no specific soft tissue or skeletal cephalometric landmark(s) or values to quantify the "fullness" of this region, so deficiency assessment of para-alar region is mainly based on qualitative profile judgment.[64]

**Surgical technique:** After general anesthésia and flap incision and elevation the osteotomy is done 2cm above the nasal floor from one side to another side To allow adequate mobilization the junction between septum and bony segment should be cut this can be done by a osteotomy.

**Figure 7:**U‐ shaped osteotomy of piriform aperture. [from Herna´ndez‐Alfaro F, Garcıa E, Martı C, Porta A. U‐shaped osteotomy in management of paranasal **Figure 7.** U- shaped osteotomy of piriform aperture. [from Herna´ndez-Alfaro F, Garcıa E, Martı C, Porta A. U-shaped osteotomy in management of paranasal deficiency. Int. J. Oral Maxillofac. Surg. 2006]
