**Core Concept:** Orthognathic surgery is a surgical procedure used to correct skeletal malocclusions, which are irregularities in the alignment of teeth and jaws. The surgery involves making horizontal and vertical cuts, known as osteotomies, to reposition the jaw bones and achieve proper alignment.

**Why the Correct Answer is Right:** Le Fort I osteotomy is a type of horizontal osteotomy that needs to be performed in the ramus (the curved part of the mandible) during orthognathic surgery. The ramus is the part of the mandible that connects the body of the mandible to the angle of the mandible and is responsible for the movement of the lower jaw. Le Fort I osteotomy involves cutting the maxilla (upper jaw) and repositioning it to correct maxillary skeletal anomalies, such as a protruding or retruded maxilla, and malocclusion.

**Why Each Wrong Option is Incorrect:**

A. Le Fort II osteotomy is a type of horizontal osteotomy performed in the sagittal plane (between the maxilla and the sphenoid bone) for the correction of midfacial deformities, not in the ramus.

B. Le Fort III osteotomy involves cutting the maxilla in a sagittal plane and a vertical plane to correct complex maxillofacial anomalies, but not in the ramus.

C. Mandibular osteotomy is a type of osteotomy performed in the mandible, not in the ramus.

D. Le Fort I osteotomy is performed in the ramus, but it is not the only type of osteotomy used during orthognathic surgery. Le Fort II and Le Fort III osteotomies are also performed, each with a specific purpose in correcting facial and skeletal deformities.

**Clinical Pearl:** Orthognathic surgery is a complex procedure involving various osteotomies to correct skeletal and dental abnormalities. While Le Fort I osteotomy is essential for correcting maxillary skeletal anomalies, other osteotomies like Le Fort II and Le Fort III are also necessary for comprehensive facial and skeletal deformity correction. It is essential for medical professionals to understand the specific types of osteotomies involved in orthognathic surgery to achieve optimal results for each patient's unique condition.