Ortho Theory + Concepts Ortho DENT 1030

What is the term for when your teeth are in their most natural position?

Maximum Intercuspation (MI) or centric occlusion

What is the Universal Notation System for deciduous/primary teeth?

A - T

What is the Palmer Notation System for deciduous/primary teeth?

Quad symbols + Letter

What is the FDI Notation System for deciduous/primary teeth?

Quad’s 5-8, tooth #1-5

Define Class I (Orthognatic) Occlusion

Mesiobuccal cusp of the maxillary first molar articulates with the buccal groove of the mandibular first molar

Define Class II (Retrognatic) Occlusion

Mesiobuccal cusp of the maxillary first molar articulates mesial to the buccal groove of the mandibular first molar

Define Class III (Prognatic) Occlusion

Mesiobuccal cusp of the maxillary first molar articulates distal to the buccal groove of the mandibular first molar

What are the two divisions of Class II occlusion? Explain them

Division 1 — the maxillary incisors are proclined (buck teeth)

Division 2 — the maxillary incicors are retroclined

What are the percentages of people with Class I, II, III occlusion?

Class I — 60-65%

Class II — 25-30%

Class III — 3-5%

What are the three types of Occlusal Relationships?

Overjet, Overbite, Crossbite

What is the normal measurement for overjet?

1-3mm

What is the normal measurement for overbite?

10-20%

What is it called if there is a negative overjet?

Crossbite

What are the requirements of an orthodontic appliance?

Function —> Comfort —> Aesthetics

What do passive appliances do?

Hold teeth in place, no forces used

What do active appliances do?

They place mechanical forces on teeth for movement

What do myofunctional appliances do?

They retrain muscles of the face (cheek, tongue, lip) in order for proper tooth alignment, jaw growth, nasal breathing etc.

What are orthodontic wires typically made of?

Stainless steel. Remember 18-8 — 18% Chromium, 8% Nickel

What is “temper” in orthodontics? How are they classified?

The hardness and flexibility of a wire

Dead soft — highly malleable and stays in the shape you bend it

Soft — partially flexible

Hard — does not bend easily, but will bend without too much force and will keep shape

Spring Hard — wants to bend back to its orignal shape

How are tube wires measured in regards to thickness?

By their inside diameter

Whats the range of sizes of Round Wires

.012” to .060”

Whats the range of sizes of Rectangular wires?

.010x.020”- .022x.025”

How do you go from ga to inches?

Always remember 18-1 (18ga is 1mm)

True or False: The smaller the wire, the larger the guage

True