Ortho

Question 1

Comprehensive diagnostic records

Answer 1

1. study models
2. 8 extra oral and intra oral photos
3. intraoral radiographs (PAN)
4. Lat Ceph w/ tracings
5. AP ceph if needed or CBCT maybe instead

Question 2

Ortho informed consent

Answer 2

1. Discussion and documentation of tx to be rendered

2. RABs and alternatives to this tx

Question 3

Risks

Answer 3

1. Caries
2. Root resorption
3. Perio
4. Necrotic pulp
5. discomfort
6. trauma
7. TMJ
8. length of tx
9. prognosis
10. relapse

Question 4

Prior to distal shoe appliance check for

Answer 4

1. Congenital heart defect, Hx of heart surgery

2. Bleeding disorder

Question 5

Risks of distal shoe

Answer 5

1. Infection

2. Perm molars get stuck under blades (blades angled mesially for this reason)

Question 6

Space maintenance on lower

Answer 6

1. Unilateral primary molar loss => band and loop
2. Bilateral primary molar loss and incisors not full in => bilateral band and loops
3. Bilateral primary molar loss and incisors in => LLHA

Question 7

To maintain leeway space for crowded pts use

Answer 7

LLHA or Nance, keep in until 12 yr molars are fully in –> this allows canines and incisors to drift distally once premolars erupt

Question 8

Lower Anterior crowding in mixed dentition treatment options

Answer 8

Mild (1-4mm): LLHA to hold leeway space and discing of primary teeth
Moderate (5-9mm): distilization of perm 1st molars, arch expansion w/ lip bumper, 2x4 (bands on 6s and brackets on incisors) and open coil springs
Severe (10mm or more): serial extraction or wait for full perm dentition and do perm extractions w/ full ortho

Question 9

Structure of Ortho Tx

Answer 9

1. Chief Complaint
2. Med HX (chemo, bisphosphonates?)
3. Dental Hx: including habits
4. Extraoral exam (Palpate TMJ, dolico, brachy, meso?, symmetry?, convex, concave, straight?, Skeletal pattern retrognathic or prognathic, nasolabial angle, lips competent?
5. Intraoral exam (OH, frenums, gingival defects, crowding, spacing, tooth size discrepancies, supernumeraries, midline, OJ, OB, crossbite?, functional?, molar and canine relationship
6. Radiographs: PAN, lat ceph to determine if skeletal or dental discrepancy
7. Photos, study models, space analysis
8. Diagnoses: stage dentition, Cl I, III, III, dolico, brachy, meso, occlusal findings etc

Question 10

Primary dentition looking for

Answer 10

Anomalies of tooth size/#
Ant or post crossbites
Habits and their effects
Open bites
Airway issues
Tx: inform parents and address as early as possible

Question 11

Mixed Dentition looking for…

take PAN when lower incisors and 1st perm molars erupted

Answer 11

Early mixed: space analysis can help once incisors in

Tx: Habits, interventions for crowding, ectopic teeth, crossbites, open bites, surgical needs, holding leeway space

Question 12

Long term sucking leads to

Answer 12

ant open bite and post crossbite

STOP by 36 months or younger

Question 13

Bruxism

Answer 13

stress, brain trauma, neuro disabilities, malocclusion

usually self limiting

Question 14

Congenitally missing teeth

Answer 14

Causes:
Cleft palate
Certain syndromes
Family patterns
Tx considerations (ext and close space or save space for prosthetic):
Age,
canine size/shape/position
occlusion and crowding
bite depth
profile
if you keep space, need interim prosthesis
moving canines –> no more canine guided occlusion
missing pm’s –>ext good for class IIIs, retaining primary can cause occlusal issues due to M-D width of primary molars

Question 15

Supernumerarys

Answer 15

Signs: asymmetric eruption pattern, overretained primarys, ectopic incisor eruption
Removal of erupted supernum –> perm incisor 75% of time
Ext of unerupted supernum when perm crown has formed completely and root length is < crown height –> normal eruptive force of normal perm incisor
Prolonged removal of supernum reduces chance that normal perm incisor will erupt on its own if apex completed
Inverted conical supernums hard to ext if delayed wcushing@comcast.net can migrate deeper
If no eruption of normal perm tooth after 6-12 months then need to do exposure

Question 16

Ectopic eruption

Answer 16

66% 1st molars self correct by age 7, recent study showed 71% self-correct by age 9
associated w/ transverse and sagittal crowding
Mild EE: elastic or metal separators
Severe EE: distal tipping of perm molar required w/ removable or fixed appliances (open coil springs or halterman)
When no canine bulge and radiographic evidence of canine overlapping formed root of lateral in MIXED dentition → EXT primary canine
RPE in early mixed dent increases potential for eruption of palatally displaced max canines
When impacted canine diagnosed later (11-16 yrs) ext of primary canine → perm eruption 75% of time as long as canine not horizontal
Ext of D’s can help w/ canine eruption too
CBCT may help with location of impacted canine

Question 17

Ankylosis

Answer 17

Cementum fuses to bone, PDL replaced w/ bone so tooth immobile to eruption
If ankylosed tooth has successor then ext if it interrupts eruption of successor or if adjacent tipping occurs
For ankylosed anterior perm teeth, can extrude w/ ortho, b/u w/ resin if minor, decoronation or ext w/ prosthetic

Question 18

Primary Failure of Eruption

Answer 18

Sometimes will become pattern for all teeth distal to most mesial tooth affected
Hallmark feature: post open bite and inability to move teeth orthodontically
Early ortho intervention should be avoided
Prepare for future prosthetic treatment, prepare for future implants or space maintenance of other teeth

Question 19

Tx to prevent crowded incisors and canine impaction

Answer 19

1. Gaining space w/ canine ext and space maintenance to allow perm incisors to erupt
2. Expansion and correction of arch length and ortho alignment of perm teeth as soon as erupted and feasible
3. Holding arches until all perm premolars and canines erupted
4. Interprox stripping of enamel of mand primary canines to allow alignment of crowded lower perm lateral incisors

Question 20

Space regaining appliances

Answer 20

Fixed: active holding arches, pendulum appliances, halterman and jones jig
Removable: Hawley w/ springs, lip bumper, head gear

Question 21

Crossbites

Answer 21

Most often unilateral post crossbites ⇐ bilateral crossbite w/ functional mandibular shift

Early correction important w/ functional shifts to avoid TMD and/or asymmetric growth

Ant can be fixed as soon as noticed if theres enough space simple w/ acrylic incline planes, acrylic retainers w/ lingual springs or fixed appliance w/ springs

Question 22

Class II Malocclusion

Answer 22

Single phase: less tx time
Two phase: Does not reduce need for extractions/surgery, longer tx time, but time in second phase can be much less, interceptive phase tx can improve self esteem although same results long term, may reduce incidence of ant tooth trauma (>3mm overjet associated w/ increase risk of incisor injury)

Tx: extra oral appliances (headgear), functional appliances, fixed appliances, extractions, interarch elastics, orthodontics w/ orthognathic surgery

Appliances: Herbst fixed, Twin block (removable)

Question 23

Class III

Answer 23

Interceptive Class III tx recommended in primary early mixed dentition

Can potentially eliminate future orthognathic surgery
Class III pts tend to grow longer and more unpredictably so surgery w/ ortho may be best tx

Tx: protraction therapy w/ or w/o RPE, functional appliances, intermaxillary elastics, chin cup therapy