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Maxillofacial Surgery
Cephalometry and Cephalometric Analysis
Built from Facial Aesthetics — Concepts and Clinical Diagnosis
What’s inside
11 sections · 186 slides
Overview
- What you will learn here
Measuring the head
What the technique is, where it came from, and why it is standardised
- Measuring a living head
- The first step: X-ray the skull instead of measuring it
- Who built the head-holder
- From dry skull to living patient
- How the patient is held still
- Why the ear rods must not be forced in
- Two standard views
- What made this different from an ordinary skull X-ray
Landmarks, lines and planes
The fixed points and reference lines that every measurement is built from
- What counts as a landmark
- From a point to a solid
- “
- Line or plane - does the word matter?
- A flat picture of a solid object
- What three-dimensional imaging adds
- Skeletal landmarks on the side view
- How to use the landmark tables
- Hard tissue lateral cephalometric (skeletal) landmarks
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Hard tissue lateral cephalometric (skeletal) landmarks (continued)
- Dental landmarks on the side view
- Hard tissue lateral cephalometric (dental) landmarks
- The pivot point inside a tooth root
- Soft tissue landmarks on the side view
- Soft tissue lateral cephalometric landmarks
- Soft tissue lateral cephalometric landmarks (continued)
- Soft tissue lateral cephalometric landmarks (continued)
- Soft tissue lateral cephalometric landmarks (continued)
- Turning points into measurements
- Horizontal reference planes
- Vertical reference planes
- Hard tissue lateral cephalometric reference planes
- Hard tissue lateral cephalometric reference planes (continued)
- Hard tissue lateral cephalometric reference planes (continued)
- Hard tissue lateral cephalometric reference planes (continued)
- Hard tissue lateral cephalometric reference planes (continued)
- Soft tissue reference lines
- Soft tissue lateral cephalometric reference planes
- Soft tissue lateral cephalometric reference planes (continued)
- Soft tissue lateral cephalometric reference planes (continued)
- Why the choice of reference plane decides the answer
The frontal film
Posteroanterior cephalometry for the face that is not symmetrical
- When you need a frontal film
- Landmarks on the frontal film
- Hard tissue posteroanterior cephalometric landmarks
- Hard tissue posteroanterior cephalometric landmarks (continued)
- Reference planes on the frontal film
- Hard tissue posteroanterior cephalometric reference planes
- Hard tissue posteroanterior cephalometric reference planes (continued)
- The frontal film is being replaced
The anatomy underneath
You cannot analyse a skull you cannot name
- Skull seen from the front
- Skull seen from the side
- Skull cut through near the midline
- Skull cut across the front of the face
- Structural components of the craniofacial complex
- The parts that make up the face
- Why no single part can be judged alone
- Describe, do not just classify
How to use an analysis
Applied geometry, its uses, and the traps that come with it
- “
- Analysis is geometry applied to a face
- A little learning is a dangerous thing
- The clinical examination comes first
- “
- Never trust one measurement
- Two terms you must keep apart
Front-to-back jaw relationships
Where the upper jaw, lower jaw and chin sit in the sagittal plane
- Dropping a plumb line from nasion
- Normal values against the nasion perpendicular
- A whole face can lean forward or back
- Comparing points A and B on the true horizontal
- Class I: upper jaw point just ahead of the lower
- Class II: upper jaw point too far ahead
- Class III: lower jaw point ahead of the upper
- The projected A-B difference
- The Delaire craniofacial analysis
- What the Delaire vertical should pass through
- The craniofacial angle
- SNA and SNB: the jaws against the skull base
- What a raised SNA can mean
- A and B are gum-level points, not bone bases
- Move nasion and the angle changes
- Check the tilt of the SN plane first
- Moving sella up or down
- A face that leans forward inflates both angles
- SND: aiming at the bone, not the gum
- SN-Pog: where the bony chin sits
- Three angles for the front of the lower jaw
- Why the front of the mandible needs three angles
- The bend in the base of the skull
- A hinge that moves the whole lower jaw
- Reading the saddle angle
- Skeletal Class: three jaw relationships
- What skeletal Class does not tell you
- The ANB angle
- 2-4°
- Nasion again: the weak point of ANB
- Face height changes what ANB means
- The same angle, a taller face
- Bite and bone do not always match
- Rotating both jaws together changes ANB
- Rotation of the two jaws as one block
- Two ways to compare the jaws without outside points
- The Ballard conversion
- How the Ballard conversion works
- Where the Ballard method struggles
- The Wits appraisal
- How the Wits appraisal is measured
- Wits values and what shifts them
- Wits: strengths and weakness
- Are the jaws the right size?
- How the two unit lengths are measured
- 20-24 mm
- Why 'small, medium, large' and not age or sex
- Midfacial length, mandibular length and lower face height
- Reading the normative table
- Normative standards in the McNamara analysis
- Normative standards in the McNamara analysis (continued)
- Normative standards in the McNamara analysis (continued)
Where the front teeth sit
Inclination and position of the incisors, which need not follow the bone
- Teeth can drift away from their own bone
- Two separate questions about a front tooth
- Which plane to measure the upper incisor against
- Upper incisor to the maxillary plane
- Where the Eastman Standards come from
- Three things the MxI-MxP number depends on
- When the crown and root do not line up
- Tilt the plane and you tilt the answer
- Upper incisor to the SN plane
- Upper incisor to Frankfort Horizontal
- Steiner's NA line
- The analysis that comes later in the book
- Upper incisor to the nasion perpendicular
- Upper incisor to the A-Pog line
- The diagnostic line
- Lower incisor inclination and the Tweed angle
- Lower incisor to the mandibular plane
- The 120-degree rule of thumb
- Two more ways to angle the lower incisor
- Steiner's NB line for the lower incisor
- Lower incisor to the A-Pog line
- The edge-centroid relationship
- Why the edge-centroid relationship predicts overbite
- The interincisal angle
- The angle between the two front teeth
- A four-angle check that must total 360
Face height, up and down
Vertical proportions, plane convergence and the normative tables
- No single vertical number will do
- Convergence of the horizontal facial planes
- Sassouni's idea of convergence
- The five planes in the modified version
- Balanced face: the planes converge behind the skull
- Nearly parallel planes: a skeletal deep bite
- Planes fanning open at the front: a skeletal open bite
- Two vertical patterns Sassouni named
- Spotting a rotated jaw
- Setting up true vertical and true horizontal
- The anterior face height ratio
- Why the skeleton reads 45:55 and the face 50:50
- The Facial Height Index
- Front height against back height
- Using the two ratios together
- The angles between the horizontal planes
- How to read the two normative tables
- Linear vertical measurements
- Normative linear vertical cephalometric measurements
- Angular vertical relationships
- Normative angular vertical cephalometric relationships
- What the UK and US numbers reveal
How far the teeth have erupted
Vertical position of the teeth against their own jaw
- Three questions about vertical tooth position
- Three ways to draw the biting plane
- Why the front of the occlusal plane wanders
- The four dental heights
- Anterior maxillary dental height
- Posterior maxillary dental height
- Anterior mandibular dental height
- Posterior mandibular dental height
Width, and pulling it together
The transverse dimension and the habits that keep you honest
- The width of the face
- The habits that keep cephalometry honest
- A short checklist for a lateral film
- References
- References (continued)
- References (continued)
- References (continued)
- References (continued)
- Facial Aesthetics: Concepts and Clinical Diagnosis, 2nd Edition