Week 8- Ortho Referrals Flashcards
What are important points of medical history from ortho perspective?
- Syndromes affecting craniofacial development
- Chronic upper airway obstruction (effects on facial development)
- Allergies
- Prev facial trauma
- High doses of drugs that interfere with bone turnover- prostaglandin inhibitors, bone resorption inhibiting meds for osteoporosis or arthritis (can impede tooth movement)
What is important dental history to gather from ortho pt?
- Dental attendance
- Caries/restos
- Diet
- OH
- Dental trauma
- Missing teeth
- TMJ symptoms
- Bruxism
- Habits
Where is facial midline?
A perpendicular line to the interpupillary line. The facial midline should pass through:
• Glabella
• Subnasale
• Philtrum of the upper lip
• Midline of the chin
What are transverse facial proportions?
- Distance between the eyes should be the same as the width of the eye
- The nose and chin should be centered within the central fifth
- The width of the nose should be about the size of the central fifth
- Width of the lips should be the same as interpupillary width
What are vertical facial proportions?
The face can be divided into three vertical regions which should be approximately the same size
• Upper third
• Middle third
• Lower third (can be further subdivided into the upper third and lower two thirds)
How can VME be managed?
Orthognathic surgery
Issue with this smile + tx?
Posterior vertical maxillary excess
- No issues with occlusion but would require orthognathic surgery
What are buccal corridors?
Defined as the space between the buccal surfaces of the maxillary teeth and the corners of the mouth during smile. Small buccal corridors are more aesthetic.
How can wide B corridors be managed?
- SME or RME as child
- If adult, would require SARPE (surgically assisted rapid palatal expansion)
How can facial convexity be visualised?
This is visualised by lines connecting glabella, subnasale and soft tissue pogonion
What is a limitation of angles classification?
Only focuses on molar class. Doesn’t indicate incisal relationship
- Molar relationship is class III but incisal relationship is class II in this pic
What happens to gingival margin as teeth over erupt?
Gingival margin moves coronally (can lead to excess gingival display)
What tx has been performed in this case?
Excess anterior gingival display. Anterior teeth intruded to correct gingival margin. Then restorative build up of incisal edges was carried out.
Issues with pts features? + tx
- Asymmetry
- Excess gingival display
- Reasonable contour
- 21 gingival margin is lower than 11
- 11 is longer than 21
- Deep bite
Tx was intrusion of upper incisors (to reduce gingival display)- more intrusion of 21 is required than 11. 21 then required incisal build up.
Identify issues + tx
- Midline shift
- Lateral open bite
- Posterior crossbite LHS
Mx expansion and then maryland bridge
What do you need to put in ortho referral letters?
- Patient: name, DOB, address
- Clinical findings
- Provisional tx plan
- Next appt scheduled, med hx any other dental tx required.
How to manage this case?
16 has over erupted so can’t restore space of 46. Would need to intrude 16 orthodontically
What deviation from midline isn’t usually noticeable?
<2mm
What can midline shift be caused by?
- Spaces
- Tooth rotations
- Missing teeth
- Incorrect tooth proportions
What is an ideal anterior tooth display on smile?
100% incisal display and up to 2mm gingival (for adolescents). 75% incisal display in minimum for acceptable facial aesthetics
What is the smile arc?
Curvature of mx incisal and canine edges. Smile arc should closely resemble the contour of lower lip (consonant smile)
What factors contribute to smile arc?
- Length of mx teeth
- Inclination of mx incisors
- Occlusion plane angle
- Intrusion/extrusion of anterior teeth
What are the goals of profile analysis?
- Establish whether jaws are positioned correctly in AP plane
- Evaluate md plane angle, lip posture and incisor prominence
- Re-evaluate facial proportions from frontal view
What is facial convexity for class II vs class III patients?
Class II: convex
Class III: concave
What are incompetent lips?
- When lips don’t meet at rest.
- If lips are incompetent, ask pt to bring lips together and observe if there is activation of circumoral muscles
What is often associated with flat vs steep md plane angle?
- Steep: long facial type and tendency for open bite
- Flat: short facial pattern and tendency for deep bite (inc overbite)
What is RCP?
Position the teeth initially contact when condyle is located in most anterior superior position in glenoid fossa
What is intercuspal position?
Position of maximal intercuspation of teeth
What is crowding/spacing a result of?
Discrepancy btwn tooth widths and size of dental arch
Issues with this case?
- Deep overbite
- 13 is impacted so primary canine is over-retained. 23 has erupted (appears larger) and could lead to midline shift
- Pt has class I facial profile
