Canines Flashcards
What is the definition of Impacted?
Tooth prevented from erupting due into it’s normal functional position due to:
• Bone
• Tooth
• Fibrous Tissue
What is the prevalence for palatal canines?
85%
What is the prevalence for buccal placed canines?
15%
Which gender is more common for impacted canines and what is the prevalence?
Females
2:1
70/30
What is the most common side for an Impacted canine and what is the prevalence:
Left
More common to be unilateral
4:1
What is the prevalence for congenital absent canines in the maxillary arch?
0.3%
What is the prevalence for congenital absent canines in the mandibular arch?
0.1 %
What is the prevalence of impacted canines in maxillary arch?
2%
What is the prevalence of an impacted canine in the mandibular arch?
0.35%
What is the prevalance of resorption of the upper incisors in 10-13 year olds?
0.7%
Development- what age do the canines start to develop?
4/5 months of age
Where is the position of the canine when developing?
High in the maxilla
Development- what age does calcification start?
6/7 years old
What age should the upper canine be palpable?
Before 11
What age should the lower canine be palpable?
Before 9
What are the eruption dates for the upper canine?
11-12
What are the eruption dates for the lower canines?
9-11
Eruption- when the upper canine migrates what direction does it take?
Forwards and downward
Eruption- After migrating, where does the canine lie regarding the deciduous canine?
Buccal and Mesial
Eruption- when erupting where is the canine positioned regarding the lateral?
Distal aspect of the root
Aetiology- what are the main cause of Impacted Canines? (6)
- Displacement of Crypt
- Long path of eruption
3.Guidance - absent lateral or short roots - Crowding
- Genetics
- Retained deciduous canines
If crowding is present where is the canine likely to be positioned in the arch?
Buccally
What three positions can a canine erupt or be positioned?
- Buccal
- Palatal
- Horizontal
What is the prevalance of short rooted or missing laterals?
42.6%
List 6 Associations with Impacted canines
- Hypodontia
- Microdontia
- IIii incisors
- Genetic
- Lack of space
- Resorption
Assessment of Impacted canines
- Palpate? ⬆️ before 11 ⬇️before 9
- Deciduous canine sturdy and mobile?
- Microdontia?
- Crowding?
- Mobility U 2-2?
Radiographs taken for Impacted Canines? (6)
1.OPG
2. Periapical
3. Upper Standard Occlusal
4. Lateral Cephlogram
5. Vertex Occlusal
6. CBCT
What Radiograph Technique is used for Impacted Canines?
Parallax Technique
What are the two types of Parallax Technique?
- Horizontal
- Vertical
What is the Horizontal Parallax Tecnique?
• Tube head moves Horizontal
• left to right
• 2 pa’s
•2 pa’s + upper standard occlusal
What is the Vertical Parallax Technique?
• Tube head moves vertical
• OPG= upwards 8 degrees
• Upper Occlusal = downwards 65 degrees
What does SLOB mean?
SAME
LINGUAL
OPPOSITE
BUCCAL
What is the average angle of a canine?
25 degrees
What is the biggest risk associated with Impacted Canines?
Resorption
Most teeth are most common with resorption from the impacted canines?
•Lateral incisor
• Can progress to Upper Centrals
What gender is resorption more common in?
Females
Interception trt of good buccally placed unerupted canines
- Palpate?
- OPG
- XLA of decidious c
- Space maintainer
Buccally displaced Canines?
• Associated with crowding
• Canine = > 1st premolar and C=
Crowding
• Buccal Mucosa and bone is thinner
• Severely displaced = xla
Trt options for Palatally placed Canines?
• surgical extraction
• expose, bond and align
• Auto transplantation
Indications for open/closed exposure?
- Motivated and compliant pt
- Good OH and dentition
- Favourable position
- Space available?
Favourable canine position depends on 4 things:
- Height
- A/P position
- Apex position
- Inclination
What are the height factors in an impacted canine?
• Higher the canine from the occlusal plane = poor prog
• if the crown is above the apical 1/3 of the incisor roots= poor prog
What Anterior Posterior factors effect Orthodontic treatment of an impacted canine?
• if closer to the midline= poor prog
• lies halfway over the central incisor= poor prog
The position of the apex of a impacted canine must not be…
Poor prog=
• further away than usual apex position
• Distal to the 2nd premolar
What is important with the inclination of the impacted canine?
If the angle to the occlusal plane decreases the greater need for traction is needed
Describe an Open exposure?
• used for good positioning
• tissues left open and packed
• attachment placed in ortho practice + traction
Describe a closed exposure?
• canine uncovered+ gold chain bonded
• stitched back up
• chain attached to wire in ortho practice
What transposition can occur with canines?
Upper= 1st premolar and lateral
Lower= lateral
What is true transposition?
Roots and crown completely interchanged
What is false Transposition?
Roots in the correct position
CROWNS have interchanged
What is Auto transplantation?
• surgically removed and reposition into the alveolar bone
Risks associated with Autotransplantation?
• inflammatory response= death of pulp tissue
• Resorption
•Ankylosis