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

What tooth numbering system is used in orthodontics?

Palmar numbering system

Define the following:

Natural spacing in primary dentition to accommodate larger permanent teeth

Primate 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?

E-Space (Leeway space)

Where is the primate space located in the maxillary arch?

Mesial to the mandibular canine (Between lateral incisor & canine)

Where is the primate space located in the mandibular arch?

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

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

0.9mm

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

1.7mm

Define the following:

The outline of hair growth on the head or face

Hairline

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

- Subnasale

- Pogonion

Define the following:

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

- Smooth area between the eyes

Glabella

What structure does this point out?

Glabella

Define the following:

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

Subnasale

What structure does this point out?

Subnasale

Define the following:

The most anterior point on the contour of the chin

Pogonion

What structure does this point out?

Pogonion

Define the following:

The most inferior point of contour of the chin

Menton

What structure does this point out?

Menton

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

Positive

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

Negative

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

Orthognatic

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

Retrognathic

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

Backwards

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

Forwards

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

Prognathic

Vertically, the entire face can be broken down into____

3rds

Who came up with the following classification:

Refers to how the maxillary and mandibular first molars relate to each other. Position of the mesiobuccal cusp of maxillary 1st molar relative to the buccal groove of mandibular 1st molar

Edward H. Angle

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

7 years old

Which growth peak according to Scammon?

- Rapid early growth

- ~80–90% complete by age 6–7

- Plateaus early

Neural growth

Which growth peak according to Scammon?

- Steady childhood growth

- Pubertal growth spurt (peak in adolescence)

- Continues into late teens

General (Somatic) growth

ID the plane of orientation:

sagittal plane

ID the plane of orientation:

frontal/coronal plane

ID the plane of orientation:

transverse plane

How can you find the facial/cephalic index?

Maximum head width x 100/ Maximum head length

What is the CI (cephalic index) for a patient that is Mesocephalic / Mesoprosopic / Normocephalic?

79-81

How would you describe the cephalic index for this patient?

Mesocephalic / Mesoprosopic / Normocephalic

What is the CI (cephalic index) for a patient that is Brachycephalic/Euryprosopic?

>81 (Short - Wide face)

How would you describe the cephalic index for this patient?

Brachycephalic/Euryprosopic (Short - Wide face)

What is the CI (cephalic index) for a patient that is Dolichocephalic/ Leptoprosopic?

<79 (Long - Narrow face)

How would you describe the cephalic index for this patient?

Dolichocephalic/ Leptoprosopic (Long - Narrow face)

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

- Glabela

- Subnasale

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

Pogonion

How would you describe the cephalic index for this patient?

Dolichocephalic/ Leptoprosopic (Long - Narrow face)

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

Occlusion

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

Obicularis oris

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

The tongue

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

Buccinator

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

Superior Constrictor

How do you describe "tip" in orthodontics?

Mesial or distal inclination of the tooth

How do you describe "torque" in orthodontics?

Labial or lingual inclination of the crown/root

What is the normal torque of mandibular posterior teeth?

Crowns are inclined lingually

Describe the ideal line of occlusion for the maxillary 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 mandibular teeth:

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

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

Maxillary 1st molar

Which tooth is the most important tooth in determining the occlusal scheme for a patient (according to Simon)?

Maxillary canines

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

Sagittal plane

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

Transverse plane

Deep bites and Open bites are are classified and evaluated in what plane?

Vertical plane

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

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

- 1st perm tooth to erupt

Describe the ideal intercuspation for a Class I occlusion:

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

Describe the intercuspation of a Class II occlusion:

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

Describe the intercuspation of a Class III occlusion:

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

ID the class of occlusion:

Class I

ID the class of occlusion:

Class II

ID the class of occlusion:

Class III

ID the class of occlusion:

Class I

ID the class of occlusion:

Class I

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

Maxillary incisors are protrusive are procumnent (proclined)

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

- Maxillary centrals are recumbent ( retrusive + retroclined)

- Maxillary laterals are procumbent ( proclined)

Define the following:

Linear more forward of its normal position

Protrusive

Define the following:

Anglularly more inclined forward

Proclined

What occlusal class presents with Maxillary incisors that are BOTH protrusive and proclined?

Class II, division 1

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 2

ID the class of occlusion:

Class II, division 1

ID the class of occlusion:

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 II, division 2

ID the class of occlusion:

Class III

ID the class of occlusion:

Class III

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

Sub-division

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

Ppseudo class III

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

- Can do edge-to-edge

- Can be guided into Class I

- Does not have retroclined lower incisors

What are Andrew's six keys to normalocclusion?

- Normal relationship

- Mesio-distal crown angulation

- Bucco-linqual crown inclination

- No rotations

- No spaces

- Flat occlusal planes

What relationship does this show?

Molar interarch relationship

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

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

- DB cusp articulates w/ distal cusp of lower molar

What does this show?

Mesiodistal Angulation of teeth - TIP

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

Distal

What does this show?

Buccolingual inclination of the teeth - Torque

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

- Curve of Spee

- Curve of Wilson