BDS3 interceptive ortho important

Question 1

what is definition of interceptive ortho?

Answer 1

Any procedure that will reduce or eliminate the severity of a developing malocclusion’

Question 2

how is space gained to accomomadate larger anterior teeth of the permanent dentition?

Answer 2

• increase in the intercanine width through lateral growht of jaws
• upper incisors erupting onto a wider arc
• leeway space

Question 3

what is leeway space of upper arch?

Answer 3

primary canine + first molar + second molar

minus

permanent canine + first premolar + second premolar

=

1 to 1.5mm

Question 4

what is leeway space of lower arch?

Answer 4

primary canine + 1st molar + 2nd molar

minus

permanent canine + 1st premolar + 2nd premolar

=

2 to 2.5mm

Question 5

what is diastema?

Answer 5

gap in between teeth

Question 6

what are the management options if a first permanent molar gets stuck between the ‘e’ and fails to fully erupt?

Answer 6

• 1. If patient <7years wait 6 months (90% self correct)
• 2. Orthodontic Separator
• 3. Attempt to distalise the first molar
• 4. Extract E
• 5. Distal disking of ‘e’

Question 7

what is case assessment of unerupted central incisors?

Answer 7

• Case history –esp. regarding trauma
• palpate labially and palatally
• if retained Primary tooth present, Is primary mobile? Is it discoloured ?
• Radiograph (AOM/ Periapical)

Question 8

how to deal with unerupted central incisor?

Answer 8

• 1. Remove primary teeth & Supernumeraries
• 2. Create space/maintain space
• 3. Monitor for 12 months
     If patient < 9 years (immature root apex)
     Still fails to erupt? OR patient >9 years (mature root apex)
• 4. Expose/bond gold chain and apply orthodontic traction

Question 9

what does early loss of decidous teeth cause?

Answer 9

localised crowding

Question 10

how does the effect of localised crowding from early loss of deciduous teeth vry?

Answer 10

• Degree of crowding already present
• Age
• Which arch? Which tooth?

Question 11

what is a balancing extraction and why?

Answer 11

o Balancing Extraction = removal of a tooth from the opposite side of the same arch
Why?
 To maintain the position of the dental centreline (preserve symmetry)

Question 12

what is a compensating extraction and why?

Answer 12

o Compensating Extraction = removal of a tooth from the opposing quadrant
Why?
 To maintain the buccal occlusion.

Question 13

what is management of early loss of A’s and B’s?

Answer 13

 little impact
 don’t balance or compensate

Question 14

what is management of early loss of C’s

Answer 14

balance

Question 15

what is management of early loss of D’s?

Answer 15

small CL. shift, balance under GA?

Question 16

what is management of early loss of E’s

Answer 16

 tend not to balance
 major space loss
 upper>lower
 Consider space maintainer- this main one

Question 17

describe compensating for a C?

Answer 17

if you remove an upper C you gotta remove a lower C

Question 18

what is a type of removable space maintainer?

Answer 18

passive URA

Question 19

what are typical components of passive URA?

Answer 19

o Retention e.g. clasp UR6,UL6 (0.7mmHSSW) Labial bow UR3 to UL3 (0.7mmHSSW) OR Southend clasp (0.7mmHSSW)
o Baseplate – extend acrylic around teeth to prevent unwanted mesial drift
o +/-Mesial Stop (0.6mm HSSW) on individual teeth if required

Question 20

what would factors of extracting carious 6’s be?

Answer 20

o Age of patient / stage of dental development
o Degree of crowding
o Malocclusion type

Question 21

when would the most ideal result of extracting carious 6’s?

Answer 21

o 7’s bifurcation calcifying
o 8’s present
o Class 1 av/reduced OB
o Moderate lower crowding
o Mild/moderate upper crowding

Question 22

what are general rules for extracting class 1 6’s?

Answer 22

o If extracting lower take upper
o Don’t balance with sound tooth. Don’t balance if well aligned or spaced.
o If extracting upper don’tneed to take lower.

Question 23

what are general rules for extracting class 1 6’s?

Answer 23

o If extracting lower take upper
o Don’t balance with sound tooth. Don’t balance if well aligned or spaced.
o If extracting upper don’tneed to take lower.

Question 24

how to clinically assess anterior cross-bites?

Answer 24

• displacement
• mobility of lower incisor
• tooth wear
• gingival recession

Question 25

what are types of cross bite?

Answer 25

* Posterior Unilateral Crossbites * posterior cross-bites * anterior cross-bites

Question 26

when is treatment of posterior unilateral cross bite needed?

Answer 26

only if it shifts midline by >2mm. so if pt bites down and between the motion to RCP he laterally shifts >2mm then thats treatment needed

Question 27

what is digit habit management?

Answer 27

1. positive reinforcement 2. bitter-tasting nail varnish 3. glove on hand, elastoplast 4. habit breaker appliance (habit deterrent) - fixed or removable

Question 28

breakdown interceptive ortho and what you do and for what?

Answer 28

-unerupted incisors - remove ob/space/obs - impacted 6's - observe 6/12 or intercept - balance c's - but not critical - carious lower 6's - take upper - uni cross bites - IOTN displacement? - habits - stop before 9

Question 29

what can be used to help fix habits?

Answer 29

detterents apliance

Question 30

what is the aetiology of infra occluding teeth?

Answer 30

ankylosis of primary tooth. surrounding alveolar bone continues to grow. primary tooth gets left behind?

Question 31

what is the diagnosis of infra occluding teeth?

Answer 31

- perucssion - check for mobility - radiographs

Question 32

what do you assess radiograph for with infra occlusion?

Answer 32

* presence /absence of successor * Ankylosis of primary tooth (no PDL space/no clear lamina dura) * Root resorption of primary

Question 33

what do you do if permanent successor is present when dealing with infra occlusion?

Answer 33

* Monitor 6-12 months * Extract if primary tooth is below the interproximal contact point * Consider extraction if root formation of successor near completion * If extract …..maintain space * Be more vigilant in upper arch

Question 34

how long do you monitor permanent successor present for infra occlusion?

Answer 34

6- 12months

Question 35

when do you extract if permanent successor is present when dealing with infra occlusion? and what do you do after if you extract?

Answer 35

* Extract if primary tooth is below the interproximal contact point * Consider extraction if root formation of successor near completion * If extract …..maintain space

Question 36

what are risks of doing nothing if permanent successor is present when dealing with infra occlusion?

Answer 36

* Permanent successor can become more ectopic * Infra-occlusion worsens with tipping of adjacent teeth - primary tooth becomes inaccessible for extraction * Caries and periodontal disease

Question 37

when does infra occlusion worsen?

Answer 37

* Infra-occlusion worsens with tipping of adjacent teeth - primary tooth becomes inaccessible for extraction

Question 38

when dealing with infra occlusion what does treatment plan depend on if permanent successor is absent?

Answer 38

o degree of crowding o degree of infra-occlusion o any other features of malocclusion ?

Question 39

when dealing with infra occlusion what do you do if you extract when permanent successor is absent?

Answer 39

plan space mangement o Either maintain space for prosthetic tooth o Reduce space to one premolar unit ( requires fixed appliance) o Close space ( fixed appliance)

Question 40

in delayed eruption when should you assess position of upper canines?

Answer 40

* Assess position of upper canines from (9 to) 10 years onwards * Should palpate by 11 years * Mobile C’s, symmetry * Angulation of lateral incisors

Question 41

when is extraction fo the c's likely to be successful?

Answer 41

o Patient is age between 10-13 years o The canine is distal to the midline of the upper lateral incisor o There is sufficient space available o The canine is less than 55 degrees to mid-sagittal plane

Question 42

what are the risks of doing nothing when dealing with ectopic primary maxillary canines?

Answer 42

o Permanent successor can become more ectopic o Permanent canine then fails to erupt (Impacted Canine) o Risk of root resorption of adjacent teeth o Risk of root resorption of canine crown (lower risk) o Risk of cyst formation around canine (rare) o Permanent canine can become ankylosed (incidence tends to increase with age)

Question 43

what are the options for growth modification for interceptive treatment of class III?

Answer 43

* Protraction headgear +/- RME (rapid maxillary expansion) * Functional appliances e.g.Reverse Twin Block / Frankel III

Question 44

when is growth modification in class III most successful?

Answer 44

- skeletal I or only mild class III - maxillary retrusion - anterior displacement on closing - avergae or reduced lower face height - patient age 8-10 years

Question 45

what are possible environmental factors of malocclusion?

Answer 45

 masticatory muscles  mouth breathing  head posture

Question 46

why tx increased overjet early?

Answer 46

* Risk of trauma - incompetent lips * Appearance – bullying/ patient self- esteem * More difficult to achieve correction once patient stopped growing