ortho (all stages) Flashcards

Question

what malocclusion does twin blocks correct. how they work. unwanted tooth movement. Ideal age

Answer 1

treats class II division 1 with increased overjet -Pulls mandible forward, resulting in musculature pulling maxillary teeth back and mandibular teeth forward. -encourages mandibular growth and reduces maxillary growth =About 75% of the effect is dental (tooth movement) and 25% change in skeletal growth -Causes lower to procline, but we want to avoid this -best in girls 11-13 + boys 12-14 during adolescent growth

Answer 2

-capable of greater range of tooth movement than removable, good for complex cases, compliance less of an issue, does not affect speech as not on palate -BUT: need good OH, have to avoid sticky hard foods, tricky to clean, can cause root resorption

Answer 3

Wires initially flexible (nickel titanium) and then use more rigid wires for tooth movement (stainless steel)

Answer 4

1. History: reason for attendance (complaint, is it realistic). Medical and dental history (motivation, phobias, trauma, OH) 2. Extra oral exam: skeletal pattern (class I, II, III) Asymmetry. FMPA, LFH. Lips, NLA. 3. Intra oral exam: teeth present, OH, periodontal state, disease, teeth with poor prognosis 4. Occlusion: Upper and lower labial & buccal segments- crowding, spacing, displacement, rotation. Incisal relationship, overjet, overbite, centre lines, molar/ canine relationships, crossbites 5. Radiographs & cephalometry findings 6. IOTN 7. Problem list, arrange referral if necessary

Answer 5

-A-P relationship: A & B points (deepest concavity of maxilla and mandible). Class I (mandible 2-3mm post to maxilla) Class II, Class III (mandible protruded) -Frankfort Mandibular planes angle: intersection of maxilla (alar-tragal) and mandible plane -Lower face height: mid=lower. Glabella to columella to menton -Transverse: Asymmetry, deviation, skeletal discrepancies -Lips: competence. Gingival display smiling. 2/3 of upper incisors should show -Nasolabial angle: 90-110 degrees

Answer 6

-75-100% -90-110 degrees -20-40% lower incisors covered -2-4 degrees -55%

Answer 7

-Frankfort plane v mandibular plane along base of mandible -on a ceph: Frankfort plane is upper margin of external auditory canal (porion) & lowest part of orbit -extra orally you cannot see these points so we tend to use the alar tragal line -If FMPA is normal, the 2 intersecting lines should meet at the back of the head. If meet in front of the back of the head, the FMPA is increased, if they meet behind the back of the head, the FMPA is reduced.

Answer 8

-Overjet: measure greatest distance between upper and lower incisors (centrals/laterals) -Overbite: when in ICP, measure vertical distance between incisor tips. Can be hard so usually done as a % of lower incisors covered by uppers. 100% common in class II div 2. 0% for class III -Complete = contact with tooth or tissues Incomplete= no contact between tooth or tissues

Answer 9

-class I: lower incisor edges occlude with or lie immediately below the cingulum plateau of the upper central incisors -class II: lower incisor edges lie posterior to the cingulum plateau of upper - Div 1 – upper incisors are proclined, OJ increased - Div 2 - upper incisors are retroclined, OJ minimal / increased -class III: lower incisor edges lie anterior to the cingulum plateau of the upper central incisors. OJ is reduced or reversed

Answer 10

-Class I canine= upper 3 occluded between lower 3 and 4 -Class I molar= MB cusp of upper 6 occludes with MB groove of lower. Cusp to cusp would be 1/2 unit class II

Answer 11

-usually upper arch is slightly wider than lower, meaning palatal cusps of upper posteriors are the functioning cusps, and lower buccal are functioning -buccal crossbite= upper is narrower than lower. Buccal cusps of the upper molars sit in the occlusal fossa of the lowers. Commonly seen in Class III -lingual cross bite (aka scissor bite)= upper arch a lot wider, so lowers site completely inside upper

Answer 12

-Mild = 2-4mm. No extraction needed. Interdental stripping -Moderate = 4-8mm. XLA -Severe = > 8mm. XLA in each quadrant +/ anchorage reinforcement

Answer 13

-function: mastication and speech. -dental health: TMJ, tooth impaction, easier to clean, caries, perio disease, trauma (reduces risk of cyst formation, root resorption of adjacent teeth, soft tissue trauma) -aesthetics: confidence, self esteem -conservation of space

Answer 14

1-root resorption: inevitable 1-2mm length loss. Increased risk if roots thin, excess force, asthma, PDL damaged 2-loss of vitality (pain and discomfort): most experience transient reversible pulpits in first 4 days. Only experience irreversible if history of trauma [can do treatment on RCT if has no PAP] 3-relapse: if retainers not worn, due to elastic recoil of PDL fibres. (Remodel over ~1year) -initial pain for 3-5 days after appliance adjustment -bone loss: usually no long term effect. Due to poor OH, excess movement, pre-existing disease -time off school due to poor aesthetics/bullying - gingival recession, gingivitis -allergy to nickel -ankylosis -root or crown damage of adjacent teeth -soft tissue trauma: from head gear (eye injuries allergy) burns, gingiva and mucosa (applying wax to brackets helps) -caries: appliances tricky to clean -TMD (little evidence) -change in profile and soft tissue contour (thick/thin lips, angles etc.) -discontinuation of treatment -dissatisfied patient

Answer 15

-essix retainers worn at night time for at least a year, then occasionally for a lifetime -Hawley retainers worn full time for 6 months, then at nights/ occasionally for a lifetime

Answer 16

-mandible growth carries on later than maxilla, so lower incisor crowding likely. End of growth is mid 20s so it is important to have retainers -natural ageing process - weak theory that mesial migration of posterior teeth due to transeptal fibres and erupting 8s

Answer 17

-small jaws -maxilla/ mandible discrepancy (class I, II, III) -habits- digit sucking -soft tissues- lip trap, active lower lip, large tongue -dental- crowding, spacing, early loss of deciduous, hypodontia, supernumerary, trauma, extractions, tooth size discrepancy, incisor inclination

Answer 18

Due to dental problems (rather than skeletal or soft tissue) -crowding, spacing, early loss of deciduous, hypodontia, supernumerary, trauma, extractions, tooth size discrepancy -fixed appliances, removal appliances, may be multidisciplinary

Answer 19

-for severe cases that a functional appliance would not work -once growth has ceased, at 18+ years -use functional appliances if still growing

Answer 20

-smaller mandible, thumb sucking (div 1), lower lip trap (div 1), active lower lip (div 2) -functional appliances -orthognathic surgery -orthodontic camouflage with fixed appliances, XLAs, anchorage -break habits

Answer 21

-Space is required to relieve crowding and reduce the overjet -commonly upper 4s. Only lower 5s if crowding

Answer 22

-bigger mandible -smaller maxilla (so crowding more common in upper) -larger tongue -use functional appliances (although less effective than in other classes) and surgery to change skeletal discrepancy -camouflage -break habits -use fixed and removable appliances to tidy up malocclusions

Answer 23

-Accept if pt is happy with their teeth - Mild –crossbite corrected with removable / fixed appliances (camouflage by proclining upper incisors and retroclining lowers) -Moderate – either camouflage treatment to hide the skeletal discrepancy or functional appliance treatment (rare) to try and modify growth -Severe – orthognathic surgery

Answer 24

-resistance to unwanted tooth movement -newtons third law= For every action (a force) there is an equal (same magnitude) and opposite reaction. Therefore, if an object exerts a force on another, the second exerts an equal an oppositely directed force on the first one -want anchorage if a tooth has to move lots to close a gap. Eg. XLA 5. 6 will move more than the anterior teeth as root surface area is less than anterior teeth. Anchorage used to keep the 6 in the position it is in -eg. Nance arch- appliance on palate eg. temporary anchorage device (mini screws into bone) eg.-headgear eg. transpalatal arch

Answer 25

GDPs never expected to plan orthodontic extractions GDPs need to understand why an orthodontist wants you to extract certain teeth Can question why an orthodontist wants something done a suggest an alternative You will be seeing patients with these applainces so need to encourage good OH Looking out for problems. And contacting patients' orthodontist

Answer 26

-position of overcrowding: -which will give appropriate space to relieve crowding, reduce overjet, reduce overbite, reduce curve of spee -prognosis (eg. hyperplastic, carious) -amount of space required -incisor/molar relationship -anchorage requirements (so would avoid 6 ideally) -appliances to be used -patient profile 4s -most common. for moderate to severe anterior crowding, reduce OJ 5s - common. for mild to moderate crowding (as narrower). or if severely displaced which is common in early loss of deciduous 6s- not too common. If poor prognosis, limited space anteriorly. Requires anchorage reinforcement. Consider compensating to prevent over eruption

Answer 27

-primary premolars and canines are larger than adults teeth so this creates space =leeway space (~2mm) -distal movement using headgear -arch expansion -incisor proclination -interproximal stripping (using files or polishing strips between teeth) -extractions

Answer 28

7s- to allow distal movement of 6 using head gear, poor prognosis, to facilitate eruption of 8 8s-Previously thought to cause lower incisor crowding, but there is no proven link. May be required for orthognathic surgery. Follow NICE guielines for wisdom tooth removal (multiple pericoronitis episodes, unrestorable caries etc.)

Answer 29

-incisors= generally OK. Don't need to balance -C and D= probably avoid as causes centreline shift. Need to consider balancing. Cs have highest risk of shift -E= AVOID as important for space maintenace, otherwise 6s drift mesially when erupting. Never balance these

Answer 30

Less than 1 second – Pizoelectric effect (normal function) 1-2 Seconds: PDL fluid expressed, tooth moves in socket 3-5 Seconds: PDL fluid redistributed, Tissues compressed = pain Longer duration: Tooth moves In socket, bony changes occur

Answer 31

3-5 seconds: Blood vessels occlude on one side 1 min: Blood flow cut off to the PDL on that side Hours: Cell death in the compressed area 3.5 days: Cell differentiation, undermining resorption begins BY osteoclasts PAIN 7-14 days: Lamina Dura is resorbed – tooth movement Tension= stretching of PDL and stimulation of osteoblasts leading to bone depositiom Compression= compressed vessels, osteoclasts cause resorption

Answer 32

-inadequate overbite -further growth

Answer 33

<18 years old with Grade 4 or 5 dental IOTN component or 6+ aesthetic component

Answer 34

1 & 2) maxilla/ mandible relative to anterior cranial base. Prognathic maxilla/ mandible increased, retrognathic if decreased 3) relative position of maxilla to mandible. >4 degrees class III, <2 class II 4 & 5) upper/ lower incisors to maxillary/ mandible plane. Proclined or retroclined incisors 6) angle between maxillary and mandibular planes. Increased=reduced overbite or anterior open bite. Reduced= increased overbite 7) LFH -columnella to menton. Increased=reduced overbite or anterior open bite. Reduced= increased overbite

Answer 35

-Why you are writing. Reason for referral. -Pt details. Previous treatment, MH, DH, motivation, OH - Features of malocclusion: incisal and skeletal relationship, pt concerns, Problems list (MOCDO), IOTN -Summary of radiographic and ceph findings

Answer 36

III As narrow maxillas or wider mandible

Answer 37

class III as mandible continues to grow Class II can get better

Answer 38

-2% -0.3% -2-8%

Answer 39

-root resorption, ankylosis, loss of vitality will affect ortho treatment

Answer 40

-anterior= for deep overbites. opens the bite to allow posterior to erupt (Dahl concept) while preventing the anteriors to erupt anymore. Vertical development of the alveolus and condyles with also grow -posterior= for anterior open bites. allows anteriors to erupt, helps to increase the overbite -only used in an actively growing patient

Answer 41

-intrusion= 15-25g -extrusion= 50g -tipping= 50-75g -rotational - 50-100g -translational 100-150g

Answer 42

-microdontia, large maxilla, small teeth, proclined upper anteriors, midline supernumerary, prominent frenum, hypodontia -physiological and may close when canines erupt -assess the cause -ortho and/ or restorative -asssess of the canine will close the diastema

Answer 43

-usually once all permanent teeth erupted (12ish) for fixed appliance -If considering functional appliance (i.e. skeletal pattern discrepancy), need to harness pubertal growth spurt (10-12 females, 11-13 males) -Consider Early referral (mixed dentition) for interceptive treatment, eg. Crossbites, Unerupted teeth (1 year after contralateral/expected) Poor prognosis 6s (around age of 9) Ectopic canines (if can’t palpate at 9) -Once growth ceased (at least 18) for orthographic surgery

ortho (all stages) Flashcards

(67 cards)