Ortho 1 - Intro + Andrew's 6 Keys (Dr. Suri)

Palmar numbering system

What tooth numbering system is used in orthodontics?

(used in international literature)

what’s the FDI tooth notation system

Primate space

Define the following:

Natural spacing in primary dentition to accommodate larger permanent teeth

E-Space (Leeway space)

Define the following:

Size difference where primary molars (D, E) are wider than their permanent replacements (premolars).

E-Space (Leeway space)

What helps with mesial shift of permanent molars?

• max: mesial to the mand canine (Between lateral incisor & canine)

• mand: distal to the mand canine (Between canine & first molar)

Where is the primate space located in the maxillary arch vs. mand?

Distal to the mandibular canine (Between canine & first molar)

Where is the primate space located in the mandibular arch?

• max: 0.9mm

• mand: 1.7mm

The average leeway space for the maxilla vs. mand was ___ (unilateral)

1.7mm

The average leeway space for the mandible was ___ (unilateral)

Hairline

Define the following:

The outline of hair growth on the head or face

1. Glabella

2. Subnasale

3. Pogonion

G S P

For a class I relationship, what 3 points would you like to be in a straight line (and also divide the face into equal 3rds)?

Glabella

Define the following:

- A single bony prominence of the frontal bone located between the superciliary arches

- Smooth area between the eyes

Subnasale

Define the following:

The point at which the nasal septum merges with the upper lip in the midsagittal plane

Pogonion

Define the following:

The most anterior point on the contour of the chin

Menton

Define the following:

The most inferior point of contour of the chin

• class II: positive

• class III: negative

Patients with class II vs. class III occlusal relationships normally will have a ____ angle of convexity

Negative

patients with class III occlusal relationships normally will have a ____ angle of convexity

1. class I: orthognathic

2. class II: retrognathic

3. class III: prognathic

O R P

what are the 3 types of facial profile for each class of occlusion

Retrognathic

In terms of facial profile, a Class II occlusion would present with a ______ profile

• class II: backwards

• class III: forwards

B F

In Class II vs. III occlusions, the mandible is said to have a ______ rotation

Forwards

In Class III occlusions, the mandible is said to have a ______ rotation

Prognathic

In terms of facial profile, a Class III occlusion would present with a ______ profile

3rds

Vertically, the entire face can be broken down into____

Edward H. Angle (father of modern orthodontics)

Who came up with the following classification:

Refers to how the max + mand 1st molars relate to each other:

• Position of the MB cusp of max 1st molar relative to the B groove of mand 1st molar

7 years old

The AAO recommends an orthodontic evaluation by what age to detect early developing problems (even if treatment isn’t started yet)?

Neural growth

Which growth peak according to Scammon?

- Rapid early growth

- ~80–90% complete by age 6–7

- Plateaus early

General (Somatic) growth

Which growth peak according to Scammon?

- Steady childhood growth

- Pubertal growth spurt (peak in adolescence)

- Continues into late teens

sagittal plane

ID the plane of orientation:

frontal/coronal plane

ID the plane of orientation:

transverse plane

ID the plane of orientation:

Maximum head width x 100/ Maximum head length

How can you find the facial/cephalic index?

1. Dolichocephalic/Leptoprosopic: <79 (long/narrow face)

2. Mesocephalic/Mesoprosopic/Normocephalic: 79-81

3. Brachycephalic/Euryprosopic: >81 (short/wide face)

D M B

L M E

3 levels of CI (cephalic index)

Mesocephalic / Mesoprosopic / Normocephalic

How would you describe the cephalic index for this patient?

Brachycephalic/Euryprosopic (Short - Wide face)

How would you describe the cephalic index for this patient?

Dolichocephalic/Leptoprosopic (Long - Narrow face)

How would you describe the cephalic index for this patient?

1. Glabela

2. Subnasale

When determining symmetry a line from what 2 points on a face determines the reference line?

Pogonion

When determining symmetry, a line from the glabella to the subnasale is the reference line, what do you evaluate the position of?

Dolichocephalic/ Leptoprosopic (Long - Narrow face)

How would you describe the cephalic index for this patient?

Occlusion

_______ is the static and dynamic relationship of the teeth and is basic to all aspects of dentistry

Obicularis oris

What muscle is indicated in grey, anterior to the maxillary incisor?

The tongue

What muscle is indicated in grey, posterior to the maxillary incisor?

Buccinator

What muscle is indicated in grey, lateral to the posterior teeth?

Superior Constrictor

What muscle is indicated in grey, more posterior to the posterior teeth?

• tip: M/D inclination of the tooth

• torque: B/L inclination of the crown/root

How do you describe "tip" vs. “torque” in orthodontics?

Labial or lingual inclination of the crown/root

How do you describe "torque" in orthodontics?

Crowns are inclined lingually

What is the normal torque of mandibular posterior teeth?

A line the follows the central grooves of the posterior teeth and the incisal edges of the anterior teeth

Describe the ideal line of occlusion for the maxillary teeth:

A line that follows the buccal cusps of the posterior teeth + the cuspal inclines of the anterior teeth

Describe the ideal line of occlusion for the mandibular teeth:

Maxillary permanent 1st molar

Which tooth is the most important tooth in determining the occlusal scheme for a patient, according to Edward Angle classification?

Maxillary canines

Which tooth is the most important tooth in determining the occlusal scheme for a patient, according to Simon’s classification?

Edward Angle’s classification

which classification of occlusion is most widely used + easiest to use

Simon’s

what classification do we use if the pt is missing their max 1st molar

Sagittal plane

Occlusal classes I, II and III are evaluated in what plane?

Transverse plane

Crossbites + midline deviations are classified and evaluated in what plane?

Vertical plane

Deep + open bites are classified and evaluated in what plane?

- Its direct(ly below) relationship with the zygomatic buttress of the zygomatic process

- 1st perm tooth to erupt

Why does Edward Angle claim that the Key tooth in the mouth is the maxillary permanent 1st molar?

When the MB cusp of the maxillary 1st molar falls into the B developmental groove of the 1st mandibular molar

Describe the ideal intercuspation for a Class I occlusion:

When the mandibular 1st molar is positioned further distal to the maxillary 1st molar

Describe the intercuspation of a Class II occlusion:

When the mandibular 1st molar is positioned further mesial to the maxillary 1st molar

Describe the intercuspation of a Class III occlusion:

Class I

ID the class of occlusion:

Class I

ID the class of occlusion:

Maxillary incisors are protrusive are procumnent (proclined)

Describe the incisors in a Class II, division 1 relationship:

- Maxillary centrals are recumbent (retrusive + retroclined)

- Maxillary laterals are procumbent ( proclined)

Describe the incisors in a Class II, division 2 relationship:

• protrusive: linear more forward of its normal position

• proclined: angularly more inclined forward

protrusive vs. proclined?

Proclined

Define the following:

Anglularly more inclined forward

Class II, division 1

What occlusal class presents with max incisors that are BOTH protrusive + proclined?

Class II, division 2

What occlusal class presents with Maxillary central incisors that are retrusive and retroclines, lateral incisors are proclined, patients present with deep bite?

Class II, division 2

Which Class II division is considered more esthetically pleasing?

Class II, division 1

ID the class of occlusion:

Class II, division 2

ID the class of occlusion:

Class II, division 2

ID the class of occlusion:

Class III

ID the class of occlusion:

Class III

ID the class of occlusion:

Sub-division

If a patient has a unilateral class I occlusion and a class II on the other side, what is that considered?

Pseudo class III

if a patient CAN occlude in class I occlusion, but because of either habit, incisor guidance or muscular pattern, the patient prefers a class III occlusion

1. Can do edge-to-edge

2. Can be guided into Class I

3. Does not have retroclined lower incisors

What are 3 clinical ways you can tell if a patient is a pseudo class III?

1. Normal relationship

2. M/D crown angulation

3. B/L crown inclination

4. No rotations

5. No spaces

6. Flat occlusal planes

What are Andrew's 6 keys to normal occlusion?

Molar interarch relationship

What relationship does this show?

1. MB cusp of the max 1st molar fits in the buccal groove of the mandibular 1st molar

2. DB cusp articulates w/ distal cusp of lower molar

According to Andrew's 6 Keys to Normal Occlusion, describe the ideal molar relationship:

Mesiodistal Angulation of teeth - TIP

What does this show?

Distal

Andrew's 6 Keys to Normal Occlusion, the teeth should have a slight _____ tip

Buccolingual inclination of the teeth - Torque

What does this show?

1. Curve of Spee: anteroposterior curve of teeth

2. Curve of Wilson: mediolateral curve of posterior teeth

What curves allow for flat curves in Andrew's 6 Keys to Normal Occlusion?

curve of monson

what do you get if you combine the curve of spee + wilson