Treatment Modalities And orthodontic Appliances Flashcards
Which factors to consider type of appliance?
- Patient concern and attitude
- Patient’s parents expectation
- Oral hygiene status
- Medical history
- Treatment Aims
Primary Dentition
- Removable appliances
- Expansion appliances
Mixed Dentition
- Removable appliances
- Functional appliances
- Fixed appliances
Secondary Dentition
- Removable appliances
- Functional Appliances
- Fixed appliances
Adult
- Removable appliances
_ Fixed appliances - Surgery
What moments pre adjusted brackets do?
- 3D controlled tooth movement
- Bodily movement
- Intrusion / extrusion
- Correct rotations
- Space closure
- Multiple tooth movements
What’s benefit of pre adjusted brackets?
- Excellent tooth control and finishing as its 3D tooth movement can be achieved.
How tipping movement achieve?
- The round wire permits the tooth to tip around a point known as the root centroid which lies about 1/3 apex of the root
How bodily movement achieve?
- The rectangular wire in rectangular bracket slot produce a force that control position of crown and root. This torque allows us to move teeth bodily.
How torque movement achieve?
-Torque allows us to control the position of the crown and root to permit us to control inclination of the tooth
Sliding mechanism?
- A Rigid arch wire usually 0.019x0.025 ss wire allows the teeth to slide along the arch wire and space to close. This space closure referred as Sliding mechanism
Types of fixed appliances
1- Standard brackets (SS / Asthetics)
2- Self ligating brackets (SS/ plastic/lingual)
3- Tip edge
Stainless steel brackets
- Pre adjusted edgewise appliance. MBT
-Slot size usually 0.022x0.028 - Allow lighter forces in early stages of treatment
- can also accommodate larger dimension wire with increased stiffness- good for arch co - coordination and sliding mechanism.
Self ligating systems
- Adv- Complete and secure wire engagement.
- less chair side
- Reduced friction
- Better OH
Dis Adv-
- Clips can fracture
- Partial ligation not possible
- Wire can slide
- Cost
- Takes practice
Ceramic Brackets
- Non metallic which are first shaped then hardened by heat
- Orthdontic Ceramic are made of Alumina
- Ceramics are harder than SS
Types
- Monocrytalline (machined by synthetic sapphire) e.g Ice (Ormco)
- Polycrystalline (injection moulding of alumina) e.g Clarity 3M
Problem with Ceramic bracket
- Increased friction
- Enamel wear - avoid in lower arch deep bite cases
- Increased bond strength can result enamel fracture at debond
- Bracket fracture - during tx or at debond
Lingual System ( Incognito)
Advantages
- Aesthetic
- No labial de calcification
- Easier to reduce an overbite and achieve arch expansion
Dis adv-
- Difficult access
- Small inter bracket span
- Speech issue
- Soft tissue soreness
- Cost
Plastic Brackets
- Not used frequently
-adv - Asthetic
Dis adv-
- Staining
- Lack of strenght
- Permanent deformation reduce 3D tooth control
Example of fixed appliance Auxillaries
- Closed coil
- Push coil
- Powerchain
- E-links
- Niti closing spring ( 12mm and 9mm)
- TPA (trans palatal arch)
- BIte turbos
- Trihelix
Slot size of fixed appliances ( pre adjusted edgewise system)
- 0.018 x 0.028 working archwire 0.016x0.022 ss
- 0.022 x 0.028 working archwire 0.019 x 0.025ss.
Removable Appliances
Your role -
- Fitting of activated by orthodontist and passive removable appliances
- assessing quality of fit and know when to reject and accept appliance
- Behavioural teaching of advice to patients on appliance management and care
- Headgear placement, activation and advice to patients
- Understanding of limitation of removable appliance
- Familiar with current role of removable appliance in orthodontic
Removable appliance
Actions:
- Tip teeth
- Enable differential tooth eruption
- Anchorage reinforcement in 3D (vertical /AP/tranverse)
- Space maintenance
- retainer
- bite planes
- Expansion
- Support distal movement e.g Nudger appliance +/- HG
- dissuade digit sucking
- Extrution of incisors or other teeth
Potential problems if Just Tip teeth?
- Aesthetic
- Dental health
- Occlusal fit
REMOVABLE APPLIANCE in lower arch
- Often used for lower retainer
- Less use for active tooth movement than URA because:
- Less undercut for retention
- less buccal sulcus for spring
- Tongue limit space for springs
- not well tolerated by patient
