Modified law method tmj

focusNode

Índice Show

Bontrager's Mandible & TMJ Anatomy & positioning
Can you see TMJ on a CT scan?
What is an Axiolateral projection?
What are the standard views to evaluate the temporomandibular joints?
What is the proper centering point for an AP axial position for temporomandibular joints?

Didn't know it?
click below

Knew it?
click below

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size Small Size show me how

Bontrager's Mandible & TMJ Anatomy & positioning

Question	Answer
Which projection of the Mandible will project the opposite half of the mandible away from the side of interest?	Axiolateral Oblique
What must be done to prevent the ramus of the mandible from being superimposed over the C-spine with an axiolateral oblique projection of the mandible?	Extending the neck.
How much skull rotation (from a lateral position) towards the IR is required with an axiolateral oblique projection for demonstrating the Ramus region?	0 degrees (True lateral)
How much skull rotation (from a lateral position) towards the IR is required with an axiolateral oblique projection for demonstrating the Mandibular body?	30 degrees
How much skull rotation (from a lateral position) towards the IR is required with an axiolateral oblique projection for demonstrating the Mentum region?	45 degrees
What is the CR angulation (along with what's the maximum angulation) needed and in which direction for all of the axiolateral oblique projections of the Mandible?	20-25 degrees cephalic with the maximum being 25 degrees.
What specific positioning error has been committed if both sides of the mandible are superimposed with an axiolateral oblique projection?	Insufficient CR angulation, or head tilt.
Which positioning line is placed perpendicular to the IR for a PA or PA axial mandible?	The OML is supposed to be perpendicular to the IR.
Where should the CR exit for a PA Mandible? Where should the CR exit for the PA axial Mandible? What is demonstrated by the PA axial?	The CR should exit around the junction of the lips. The CR should exit around the Acanthion. The PA axial demonstrates the TMJ region & Condylar heads.
What CR angulation and which direction is for the PA axial projection of the mandible? What CR angulation is required for the PA mandible projection?	CR 20-25 cephalic for the PA axial mandible. CR perpendicular for the PA mandible.
For the PA mandible projection of the Mandibular body, What portion of the patient's face will be against the IR? What positioning line will be perpendicular to the IR. How does the mandible body position relate to the IR?	The patient's nose & chin against the IR bringing the AML perpendicular to the IR and bringing the body perpendicular to the IR.
For the PA mandible projection of the Ramus, What portion of the patient's face will be against the IR. Which positioning line will be perpendicular to the IR. What will the Ramus position be in relation to the IR?	The patient's forhead & nose should be against the IR bringing the OML perpendicular to the IR which puts the Ramus parallel to the IR?
For an AP axial projection of the Mandible/TMJ, what CR angulation & direction is required if the OML is perpendicular to the IR? How much if the IOML is perpendicular to the IR? What CR angulation should be maintained? Where should the CR be centered?	35 degrees caudad if OML is perpendicular to IR & 42 degrees caudad if IOML is perpendicular to IR. a 35 degree caudad angle to the OML. The CR should be centered to the Glabella.
Which projection of the TMJ requires that the skull be kept in a true lateral position? What CR angulation & which direction is required? Where should the CR be centered?	The Schuller Method requires the skull to be in a true lateral position. The CR should be 25-30 degrees caudad. 1/2" anterior & 2" superior to the upside of the EAM.
Which projection of the TMJ is the Axiolateral oblique projection? How much skull rotation from lateral? How much Cr angulation and which direction is required? Where should the CR be centered?	The Modified Law Method. 15 degrees towards to the IR. A 15 degree caudad angle. CR centered 1/2" superior to the upside of the EAM.
Which direction do the mandibular condyles move as the mouth is opened?	The mandibular condyles move anteriorly.
For an axiolateral oblique projection of the mandible what are 3 ways to avoid superimposition of the opposite mandible?	Angling the CR 25 degrees cephalic from the IPL. A 25 degree head tilt towards the IR. A combination of head tilt & CR angulation not exceeding 25 degrees.
Which TMJ projection method would both TMJ's be in vertical alignment? Why is this?	The Schuller Method because there's no head rotation.
If a radiograph of an axiolateral oblique projection of the mandible reveals the body of the mandible being very foreshortened & the body is the area of interest. What lead to this?	Insufficient rotation of the head. The head should be rotated 30 degrees from lateral towards to the IR.
What is the region of the mandible that divides each half of the mandible into a superior & inferior part?	The Gonion
Which area of the mandible is anterior to the Gonion? Which area of the mandibule that's superior to the Gonion?	The Mandibular body is anterior to the Gonion. The Ramus is superior to the Gonion.
What is the Alveolar Process on the Mandible?	The ridge where the lower teeth are located that receive the roots of the teeth.
Which process is anterior to the Condyloid process on the Mandible?	The Coronoid process.
What is the region on the mandible that's in between the Condyloid process and the Coronoid process.	The Mandibular notch.
Where is the Temporomandibula Fossa located?	On the Temporal Bone just anterior & slightly superior to the EAM.
Which region is the Mental Point? Which region is the Mental Protuberance? Which region is the Mentum?	The Mental Point is at the center of the Mental Protuberance. The Mental Protuberance is the flat triangular surface below the symphysis. The Mentum is the entire area.
What is the Condyloid Process made up of?	The Condyle or the Head which is the rounded end of the Condyloid Process & the Neck which is the area directly below the head.

Can you see TMJ on a CT scan?

First used for TMJ evaluation in 1980 [24], CT is considered to be the best method for assessing osseous pathologic conditions of TMJ. It allows a multi planar reconstruction (sagittal, axial, coronal) of TMJ structures, obtaining 3D images in closed and opened-mouth positions.

What is an Axiolateral projection?

Axiolateral Projection - Right or Left Positions. Abnormal relationship or rang of motion between condyle and TM fossa is shown. Usually these projection taken in open and closed mouth positions.

What are the standard views to evaluate the temporomandibular joints?

Many different views such as the submentovertex, transmaxillary, and the transcranial are used to reduce superimposition. Ultrasound is a less expensive and easily performed imaging modality that can be used to evaluate the TMJ. This is simple way to look for the presence of a joint effusion[21].

What is the proper centering point for an AP axial position for temporomandibular joints?

Central Ray and Collimation: Central ray is 35° caudad from OML or 42° from IOML. Central Ray is directed to 1 inch anterior level of temporomandibular joint or 2inches to EAM. Image receptor is in the center of Central Ray.