Ortho Flashcards
Describe class I incisors
The lower incisor edges occlude with or lie immediately below the cingulum plateau of the upper central incirors
Describe class II div 1 incisors
The lower incisor edges lie posterior to the cingulum lateral of the upper incisors
The upper incisors are proclined or of average inclination and there is an increase in overjet
Describe class II div 2 incisors
The lower incisor edged lie o sterile to the cingulum lateral of the upper incisors
The upper central incisors are retroclined
The overjet is usually minimal or may be increased
Describe class III incisors
The lower incisor edges lie anterior to the cingulum plateau of the upper incisors
The overjet is reduced or reversed
What are the dental factors of a class II div 1 malocclusion?
Increased OJ - incisors proclined or average
Variable OB
Can have good alignment, crowding or spacing in dentition
Habitually parted lips may lead to drying of the gingivae and exacerbation of any pre existing gingivitis
What are the reasons for treating a class II div 1 malocclusion?
Concerns re aesthetics
Concerns re dental health
Prominent incisors at risk of trauma esp with incompetent lips
If OJ>9mm, pt 2x more likely to suffer trauma - IOTM 5A
What are the tx options for a class II div 1 malocclusion?
Accept - leave and monitor
Attempt growth modification
URA
Orthognathic surgery
When can a class II div 1 be accepted and monitored?
When there is a mildly increased OJ and if pt isn’t concerned
Can give advice and use of mouth guard for trauma protection
How is growth modification used in a class II div 1?
Headgear - try and restrain grown of maxilla
Functional appliance - utilise, eliminate or guide the forces of muscle function, tooth eruptions and growth to correct the malocclusion - should be used during growth and coincide with pubertal growth spurt
How can URAs treat class II div 1?
Limited role unless very mild class II, when OJ is due to incisor proclination and if OB is favourable
How is orthognathic surgery used to treat class II div 1?
Carried out when growth is complete and only when there is severe skeletal A/P discrepancy or vertical direction
Usually involves mandibular surgery but may involve maxilla
Fixed appliances will be required before, during and after surgery
What are the components of URAs?
A - active component (moves teeth, 0.5mm)
R - retention (holds the brace in, 0.7mm in permanent, 0.6mm in primary)
A - anchorage (resists unwanted tooth movement)
B - baseplate (+ any modification) - self cure PMMA, provides retention and is a connector
Why is self cure PMMA used over heat cured in baseplates?
Quicker and easier to fabricate - takes 14 minutes rather than 14 hours
Design a URA to reduce an overbite
A -
R - 16,26 Adam’s class 0.7m HSSW
A - Y
B - self-cure PMMA, FAMP OJ+3mm
Design a URA to reduce OJ and continue to reduce OB
A - 22, 21, 11, 12 Robert’s retractor 0.5mm HSSW + 0.5mm ID tubing
R - 16, 26 Adams clasps 0.7mm HSSW + 3/3 mesial stops
A - (not ideal, keep eye on it)
B - Self-cure PMMA and FABP OJ+3mm
Design a URA for retracting canines
A - 13, 23 ala tal finger spring + guard 0.5mm HSSW + ID tubing
R - 16, 26 Adams class 0.7mm HSSW + 11, 21 Southend clasp 0.7mm HSSW
A -
B - self-cure PMMA
Design a URA for retracting buccally placed canines
A - 13, 23 buccal canine retractor 0.5mm HSSW + 0.5mm ID tubing
R - 16, 26 Adams class 0.7mm HSSW + 11, 21 Southend class 0.7mm HSSW
A -
B - self cure PMMA
Design a URA for correcting an anterior crossbite
A - Z-spring 0.5mm HSSW
R - 16, 26 Adams class 0.7mm HSSW + 14, 24 Adams class 0.7mm HSSW
A -
B - self cure PMMA + posterior bite plane
Design a URA for a posterior crossbite
To expand upper arch
A - midline palatal screw
R - 16, 26 Adams clasps 0.7mm HSSW and 14, 24 Adams clasps 0.7mm HSSW
A - reciprocal anchorage
B - self cure PMMA + posterior bite plane
Name some common component faults in a URA
Z-spring incased in acrylic
Adams clasp flyover or arrowhead fault
Name some common prescription faults for URAs
Southend clasp inclusion so appliance won’t work
Adams clasp on wrong tooth
FABP instead of PBP
How can you rectify errors on URAs
Re-make appliance by taking new imps
How do you activate a palatal finger spring?
Using spring former pliers - 1-2mm activation
How do you fit a URA?
Check appliance for correct pt and what you asked for
Run finger over all surfaces to check protruding wires and sharp acrylic
Check wirework integrity
Fit appliance
Check for blanching or trauma
Check posterior retention - flyovers first, then arrowheads
Check anterior retention
Activate to reduce 1mm movement/month
Demo to pt insertion and removal
Review 4-6 weekly
What instructions should you give pts re URAs?
Will feel big and bulky
Likely to impinge on speech - start reading book aloud to speed up adjustment
May have mild discomfort - particularly on teeth being moved - sign appliance is working
Initial increase in saliva 24-48 hours
Wear 24 hours/day inc meal times
Can remove to clean with soft brush after meals or when participating in active/contact sports - store in safe place
Avoid hard and sticky foods
Be cautious with hot foods and drinks as baseplate is insulator
Non-compliance will lengthen tx
Give emergency contact number
How can you explain decalcification to a pt?
Stained spot on the tooth with the same shape of the bracket
Weakens the enamel to caries
When is decal most likely?
History of caries
Evidence of decal
NCTSL
What OHI should be given to ortho pts?
Toothbrushing + single tufted brush for brackets
ID brushes + suerfloss
Brush minimum 2x daily very thoroughly
Dry toothpaste - work from upper right clockwise to lower right, brush at 45ºangle, between gum and tooth, brush in short scrubbing motion for min 2 minutes, spit don’t rinse
Brush after meals as brackets trap food and plaque
Use disclosing tablets to identify missed areas
What diet advice should be given to ortho pts?
Limitation sugar amount and frequency
Avoid snacks between meals - limit sugar to <3 times daily
Avoid hard/hot foods, fizzy drinks, sports drinks, sticky sweets, chewing gum
Ideal drinks are water or milk, crackers, cheese, fruit is acceptable but be careful of fat in cheese and natural sugar/acid in fruit
Watch out for hidden sugars eg - ketchup
Rinse mouth after eating
What flouride toothpaste can be given to ortho pts?
Duraphat - 2800ppm (0.619%) - 5000ppm (1.2%)
Twice daily, ordinary toothpaste at other times
Warn re overdose and keep away from children
What mouthwash can be used for ortho pts?
Daily 0.05% fluoride mouthwash (225ppm)
Use in between brushing, not before or after
What is the fluoride varnish advice for ortho pts?
Proflurid (22,600ppm) - not duraphat
Every 4 months
This is for prevention, not used for decal as it seals it in
What fluoride prescriptions can be given for ortho pts?
Sodium fluoride toothaste 0.619% (2800ppm)
- 75ml, brush for 1 minute after meals using 1cm before spitting out 2x daily
Sodium fluoride toothpaste 1.1% (5000ppm)
- 51g, brush for 3 minutes after meal using 2cm, before sitting, 3x daily
Give 2 dental health implications from ectopic canines?
Risk of root resorption
Risk of cyst formation
What are the causes of a retained A/uneruted 1?
Trauma to A causing damage to 1
- complications: ankylosis, arrested tooth formation (1), dilaceration, displacement
Lack of permanent successor (hypodontia)
Ectopic tooth germ
Crowding
Supernumerary - tuberculate most common
What investigations should be taken for a retained A/uneruted 1?
Radiograph localisation for ortho tx
Another A or anterior occlusal
Alternately OPT and occlusal
CBCT for 3D view
What are the signs that an A is retained and 1 is unerupted?
Discolouration of A
Retained A
Lateral erupted before central
Seen on radiograph
What are the management options for retained As/unerupted 1s?
Always palpate - usually 1 is buccal and central (high)
Leave and monitor- inform of possible cyst formation
Extract A (leave 1) and save maintenance (warn of cyst formation)
Surgical removal of both teeth and space maintenance
Refer for orthodontic opinion/tx - inform of possible ortho tx benefits/risks
Auto-transplantation
Extract A and hope for spontaneous eruption - unlikely if dilacerated
Expose (close or open) +/- bonding/traction - won’t work if dilacerated
What are the tx options for a class III malocclusion?
Accept and monitor
Internet with URA - proclined upper incisors
Growth modification
Camouflage with fixed appliance
Orthognathic surgery
How can growth modification be used to treat a class III?
Functional appliance - reverse twin block or RME + protraction headgear
How can camouflage be used to treat a class III?
Accept underlying skeletal class problem, move teeth with fixed ortho to hide it
Proclined users and retro line lowers
Risks - decal, root resorption, relapse, gingival recession
Usually together with XLA U5s and 4s
How can orthognathic surgery be used to treat a class III?
With combined orthodontics
Need MDT - orthodontist, Maxfax surgeon, clinical psychologist, GDP
Pre-surgical ortho - 12-18 months - arch alignment, arch coordination, de-compensation
Post-surgical ortho - 12 months
Total time 36 months
