1. National Diploma in Dental Nursing
Module- 15
Orthodontics

2. Orthodontics In this module you will learn about:
1. Classification of malocclusion
2. Reasons for malocclusion
3 Different types of malocclusion
4. Intraoral orthodontic appliances
5. Extra-oral orthodontic appliances

3. Orthos = straight Odons = tooth
Orthodontics
Orthos = straight Odons = tooth
Orthodontics is the study and treatment of malocclusions.
Occlusion = the way the upper & lower teeth contact each other during biting and chewing.
Malocclusion = abnormal alignment or contact between the upper and lower teeth caused by irregularities of the teeth or jaws

4. Mechanism of tooth movement
Orthodontic appliances put force on the teeth. This force is transferred to the periodontal ligaments and alveolar bone causing them to remodel.
Remodelling means that the ligaments and bone are temporarily injured by the forces allowing the teeth to move. As the teeth move the bone and ligament are rebuilt again and after the forces are removed the bone and periodontal ligament return to their normal state.

5. Aim of Orthdontic Treatment
The aim of orthodontic treatment is to straighten the teeth or reposition the jaws so that function and aesthetics are improved.
Straight teeth mean patients can maintain better oral hygiene.
Aligning the teeth can help impacted teeth to erupt.

6. Assessing the need for orthodontic treatment
The Index of Orthodontic Treatment Need (IOTN) is used to assess the need and eligibility of children under 18 years of age for free NHS orthodontic treatment.
The assessment takes into consideration 2 factors:
Dental Health
Aesthetics

7. 1. Dental health
Patients’ dental health is given a grade from 1 to 5 depending on the following:
Number of missing teeth
Severity of changes in overjet and overbite
Presence of crossbite
Distance between contact points of adjacent teeth

8. 1. Dental health grading IOTN 1 Almost perfection IOTN 2
Minor irregularities
IOTN 3
Greater irregularities which normally do not need treatment for health reasons
IOTN 4
More severe degrees of irregularity and these do require treatment for health reasons
IOTN 5
Severe dental health problems

9. 2. Aesthetics
The NHS does realise that some children need orthodontic treatment just because their teeth look really bad. The Aesthetic Component is a scale of 10 colour photographs showing different levels of dental attractiveness. The grading is made by the orthodontist matching the patient to these photographs.

10. So who qualifies for treatment?
 In the NHS, patients whose IOTN dental health score is 4 or 5 automatically qualify for treatment.
Patients with IOTN 3 are borderline cases who usually do not need treatment for health reasons but might get it for aesthetic reasons. Patients with an IOTN dental health score of 3 AND an IOTN aesthetic score of 6 or greater will qualify for treatment.

11. Pre- treatment Patient Care
1. Inform patient & parent/guardian about treatment:
Type of appliance
Will teeth be extracted or not
Length of treatment
Frequency of future appointments
Importance of compliance
Importance of good oral hygiene during treatment
Risk of treatment – root resorption, soft tissue trauma, poor oral hygiene, no compliance
Make patient aware would have to wear retainer for life after end of treatment
2. Obtain written consent from patient/guardian

12. Records for planning Orthodontic treatment
1. Radiographs
a) dental panoramic tomograph – to check for impacted or supernumerary teeth, bone lesions. Also known as an OPG.
b) bitewings – to check for caries
c) lateral cephalograph – to assess jaw relationship
d) occlusal x-rays – to check for impacted teeth
2. Study models
3. Intra-oral & extra-oral photographs
4. Dental & medical history

13. Dental Nurse’s Role during Treatment
1.Prepare patient records.
2.Help with taking and developing of X-rays
3.Mix alginate for study model impressions
4.Help with taking of intra-oral photographs by holding intra-oral mirror and blowing air on it to prevent misting up while dentist takes photos
Cheek retractors
Intraoral mirrors

14. Reasons for Malloclusions
1. Skeletal problems
a) jaws too small or big
b) mandible and maxilla do not meet properly
2. Dental problems
a) teeth too big (macrodontia) or too small (microdontia) for arches
b) extra-numerary/supernumery teeth, e.g. mesiodens
c) missing teeth (hypodontia)
d) bad habits, e.g. thumb sucking

15. Classification of malocclusion
Overjet is the distance between the labial surface of the lower incisors and the palatal surface of the upper incisors when the teeth are in occlusion.
Overbite is the vertical overlap of the upper and lower incisors when the teeth are in occusion

16. Angle’s Classification of Malocclusion
Normal Occlusion
Molar relationship – the mesio-buccal cusp of the upper first molar occludes with the buccal groove of the lower first molar.
Incisal relationship -The mandibular incisor edges occlude with or lie immediately below the cingulum plateau of the maxillary central incisors.
The overjet and overbite are 2-4 mm
The midlines of the upper and lower arches meet.
All teeth are in a smooth arch in the jaws.

17. Angle’s Classification of Malocclusion
CLASS 1 MALOCCLUSION
Molar relationship is normal - the mesio-buccal cusp of the upper first molar occludes with the buccal groove of the lower first molar but the other teeth are not aligned properly - might be crowded, have distemas (gaps), crossbites, etc.
OPEN BITE
MEDIAN DIASTEMA
CROWDING
CROSSBITE

18. Angle’s Classification of Malocclusion
*CLASS II division 1 MALOCCLUSION
Molar relationship – mesiobuccal cusp of the upper first molar lies in front of the buccal groove of the lower first molar (mandible is further back than normal)
Incisal relationship - upper incisors
bite in front of lower incisors but are
proclined (slope towards the lips which
means increased overjet)

19. Angle’s Classification of Malocclusion
*CLASS II division 2 MALOCCLUSION
Molar relationship – mesio-buccal cusp of the upper first molar lies in front of the -buccal groove of the lower first molar (mandible is further back than normal)
Incisal relationship - upper incisors
bite in front of lower incisors but
are retroclined (slope away from the
lips & overjet is reduced)

20. Angle’s Classification of Malocclusion *Class III MALOCCLUSION
Molar relationship - mesio-buccal cusp of the upper first molar lies behind the buccal groove of the lower first molar (mandible is in front of maxilla)
Incisal relationship – upper incisors bite behind lower incisors (mandible is in front of maxilla – reverse overjet)

21. Treatment options
1. Extraction usually of premolars done before using orthodontic appliances to make space in the dental arch.
2. Intra-oral appliances
i) Removable appliances used to tilt teeth or act as retainers after treatment is finished.
ii) Fixed appliances used to move teeth along the arch.
Iii) Functional appliances
3. Extra-oral appliances
I) Head gear – used in addition to fixed or removable appliances to provide extra anchorage

22. Removable appliances Advantages:
1. Can be taken in and out by patient for eating and cleaning
2. Can be adjusted by patient at home
3. Inexpensive compared to fixed appliances
Disadvantages:
1. Can not move teeth but only tilt them
2. Can be taken out by patients when it shouldn't be
3. Can affect speech

23. Parts of a removable appliance
screw
Spring activated appliance
Screw activated appliance

24. Parts of a removable appliance
1. Acrylic base plate – connects all the metal components and gives the appliance stability
2. Labial bow – metal wire which runs over anterior teeth to help keep appliance in place
3.Clasp or Adam's crib – metal loop on molars to hold appliance in place
4. Finger spring – active component used to move teeth
5.Screw – active component for widening the jaws. A key is inserted and turned by the patient or dentist once every few weeks.

25. Invisalign® / Clear step® - Removable appliances
A series of clear/ transparent aligners which fit over the teeth.
Each is worn for 2 weeks. Each aligner straightens the teeth gradually.
Composite material is placed on facial surface of teeth to help move them.
Space to move the teeth is made by stripping (filing) the teeth interproximally.

26. Functional appliances
A functional appliance is removable and uses the forces of the muscles in the lips and cheeks to move the teeth and fix skeletal discrepancies .
Used only while the jaws are growing to fix class II & III malocclusions.
Should be worn full time.

27. Retainers
At the end of orthodontic treatment patients need to wear retainers to stop the teeth moving back to their original position.
Removable retainers can be taken out for cleaning.
Fixed retainers are a wire cemented to the lingual/palatal surface of teeth – difficult for patient to floss.
Should be worn full time for first 6months and then during the night for ever.
Clear retainer
Hawley retainer
Fixed retainer

28. Fixed appliances
Fixed appliances are cemented to the teeth so they can not be removed by the patients during treatment. This is an advantage with patients with low compliance (don't want to wear them).
Extra care must be taken to maintain good oral hygiene.
They can tilt and bodily move teeth – can do more than removable appliances and so are more complicated to make and cost more.
The components of a fixed appliance system are:
1. Molar orthodontic bands or tubes
2. Orthodontic brackets
3. Archwires
4. Elastics and metal ligatures,

29. Components of fixed appliances
1. Molar orthodontic bands
Cemented with GIC on molar teeth to provide anchorage for the archwires.
An elastic separator may be placed around the tooth on which the band will be to make space for the band (for 7-10 days before cementation)
Elastic separators
Molar band

30. Components of fixed appliances
2. Brackets
Can be made of stainless steel, porcelain or plastic.
The back of the bracket is shaped to fit the tooth surface.
The front of the bracket has:
- a slot in which will fit the archwire (Edgewise brackets have horizontal slots, Begg brackets have vertical slots)
- wings around which will fit the elastics and ligatures
Brackets are bonded on with composite resin – need etch and bond

31. Components of fixed appliances
3. Archwires
Made of metal e.g. Nickel titanium, stainless steel.
Fit in the slots of brackets to pull the teeth in a given direction.
Can be round or triangular in shape and have different widths.
Different wires are used in the different stages of treatment.

32. Components of fixed appliances
4. Ligatures
Can be either thin metal wires or elastic.
Hooked on wings of brackets to hold the archwire in place.
Changed throughout treatment.

33. (A) Brackets: Metal attachments, which are bonded directly to the teeth. (B) Archmire: Runs throuh a slot in the brackets providing pressure to slowly move teeth. (C) Band: Metal rings which are cemented around the bicuspid or molar teeth. (D) Elastic modules: Coloured or clear tiny elastics that hold the arch wire into the bracket.
(E) Ligature Wire: Tiny wires that tie the arch into the bracket instead of using a tie. (F) Hooks: Used to attach elastics (rubber bands). (G) Coil Spring: Fits between brackets and over arch wires to hold or expand space. (H) Power Chain: Continuous elastics

34. Instruments used in orthodontics
Adams univ. pliers
Maun's wire cutters
Bracket forceps
Bracket remover
Band pusher
Mosquito forceps

35. Head gear Components of headgears:
1. Facebow made of an inner bow which is attached to the tubes on the molar teeth and an outer bow which is attached to the head cap.
2. Head cap fits over top of head to provide anchorage
3. Neckstrap fits across back of neck to pull molars distally (back)
Inner and outer bows

36. Instructions for wearing appliances
General rules
Avoid sweet, sticky and hard foods
Avoid fizzy drinks
Attend general dental check ups regularly
Attend orthodontic appointments regularly
If appliance breaks go to dentist immediately
Maintain excellent oral hygiene

37. Instructions for wearing appliances
For fixed appliances
Brush teeth regularly & use fluoride mouth rinses
Use inter-dental brushes to clean around brackets
Use ribbon wax over brackets to protect soft tissues
Avoid sticky foods as they can pull off brackets
Cut food into bite sixed pieces

38. Instructions for wearing appliances
For removable appliances
Brush and floss teeth regularly
Wear appliance as much as advised by dentist (normally only to remove for brushing or playing sports)
Take out to clean with tooth paste and tooth brush- Clean over a sink of water to avoid breakage)
Turn the screw as advised by dentist

39. Any Questions???