X-RAY POSITIONING OF THE MANDIBLE (2020 UPDATED)

Summary

This educational video script focuses on radiographic positioning of the mandible, emphasizing the challenges due to its superimposed and curved structure. It details various projections, particularly the PA mandible, to visualize fractures clearly without superimposition. The script also discusses alternative views like the OPG, lateral mandible, and axiolateral projections for specific cases, highlighting the importance of proper patient positioning and equipment use for accurate diagnostic imaging.

Takeaways

• 🦷 The video discusses the radiographic positioning of the mandible, emphasizing the challenges due to its superimposition by other structures and curved shape.
• 👨‍⚕️ It is recommended to watch this after understanding the cranial vault, facial bones, and sinuses from previous videos.
• 📚 A PDF presentation is available for further study on pathologies like fractures that can occur in the facial bones and mandible.
• 🔍 The PA (Posteroanterior) mandible projection is the most frequently used technique to visualize fractures without superimposition.
• 🔬 The PA mandible projection requires specific positioning with the orbitometal line and interpupillary line horizontal, and no tube angulation.
• 📏 The positioning for the PA mandible projection aims to elongate the mandible to make fractures more visible and assess displacement.
• 👂 The OPG (Orthopantomogram) is a valuable projection for the mandible but requires specialized equipment not available in all centers.
• 👁️ The Lateral mandible projection is less common due to the difficulty in interpreting superimposed mandibular sides but is useful in certain cases.
• 🦴 Axiolateral projections are used to examine specific areas like the temporomandibular joints (TMJs) when an OPG is not available.
• 🤹‍♂️ Positioning for axiolateral projections requires precise angles and patient positioning to isolate and visualize the area of interest.
• 📐 The Orthopantomogram works by exposing a small area of the image receptor at a time while rotating around the patient to flatten the curved mandible structure.

Q & A

What is the main challenge in performing radiography on the mandible?

The main challenge in performing radiography on the mandible is that it is a curved structure and is superimposed by many other structures, making it difficult to see fractures without any superimposition.

Why is the PA mandible projection frequently utilized in radiographic projections of the mandible?

The PA mandible projection is frequently utilized because its purpose is to elongate the mandible maximally, allowing for the clear visualization of fractures without superimposition, especially those with lateral displacement.

What is the recommended technique for the PA mandible projection according to the video?

The recommended technique for the PA mandible projection involves having the orbitometal line and interpupillary line horizontal, with no tube angulation, and centering in the midsagittal plane at the level of the mid-mandibular angles.

What is the purpose of the lateral mandible projection?

The purpose of the lateral mandible projection is to provide a view of the mandible in a true lateral position, which can be useful when there is a query of a mandibular fracture, despite the superimposition of the two mandibular sides.

How should the patient's head be positioned for a lateral mandible projection?

For a lateral mandible projection, the patient's head should be in a true lateral position with the interpupillary line horizontal, and the central ray should pass through the mid-mandible.

What is an Orthopantomogram (OPG) and how is it beneficial for mandible radiography?

An Orthopantomogram (OPG) is a specialized projection that exposes a small area of the image receptor at a time while rotating around the patient, resulting in a flat representation of the curved mandible structure. It is beneficial as it shows the entirety of the mandible in one structure, which is useful for identifying fractures or other pathologies.

What are some common issues with OPG positioning and how can they be avoided?

Common issues with OPG positioning include improper alignment of the bite plane, patient movement, and interference from broad shoulders. These can be avoided by ensuring the patient's bite plane is in a slight smile position, instructing the patient to stay still, and adjusting the patient's position to prevent shoulder interference.

Why is it important to remove metallic foreign bodies before performing an OPG?

It is important to remove metallic foreign bodies before performing an OPG to prevent artifacts on the image, which can obscure the view of the mandible and other facial structures.

What is the purpose of the axial lateral projection for the temporomandibular joints (TMJs)?

The purpose of the axial lateral projection for the TMJs is to project the target TMJ above the rest of the bones of the base of the skull, allowing for a clear view of the joint, which is particularly useful when querying a disruption to the TMJs.

How can the axial lateral mandible projection help in identifying fractures of the mandibular ramus or angle?

The axial lateral mandible projection helps in identifying fractures of the mandibular ramus or angle by separating the mandibular angles and rami, allowing for a clearer view of the target area, which can be particularly useful when an OPG is not available or suitable.

What supplementary projection is recommended to complement the OPG for a more comprehensive radiographic examination of the mandible?

A supplementary projection such as the PA mandible is recommended to complement the OPG. This allows for the visualization of any displacement of fragments, which may not be clearly seen in the OPG due to superimposition in the midline over the cervical spine.