H - Operative Flashcards
When to avoid veneers?
Poor OH and diet High caries rate Gingival recession High lip lines Extensive prep needed heavy occlusal contacts
Alternatives to veneers?
No Tx Micro-abrasion internal bleaching direct composite Crowns
What are some problems with tooth bleaching?
Can burn or irritate the gingivae
Can make the teeth sensitive
Relapse of colour
WIll change the colour of the teeth but not the restorations
Give examples of extrinsic and intrinsic tooth discolouration?
Extrinsic - smoking, tea, coffee, red wine, chlorhexidine
Intrinsic - Fluorosis, non-vitality, tetracycline
Types of bruxism?
centric - clenching may be due to nerves
Eccentric - parafunction, involuntary grinding or clenching
What is Posselts envelope
ICP-E-Pr-T-R-RCP-
Describes the dynamic movements of the mandible
What 6 positions make up Posselts envelope?
ICP-E-Pr-T-R-RCP-
Risks of internal bleaching?
May not work
May cause external cervical resorption
What are occlusal interferences?
Undesirable tooth contacts that may produce mandible deviation during closure to ICP
Functions of muscles of mastication?
Temporalis - elevates and retracts
lateral Pt - elevates, protrudes, depresses and lateral movement
Medial Pt - elevates and protrudes
Masseter - elevates and protrudes
3 measurements to determine the length of a post? How much GP apically
How far does it extend into the root
What is the ratio with the crown?
4-5mm GP apically
1/2 to 2/3 length of the root
1:1 ratio with the length of the crown?
What are the principles of crown prep (6)?
Preserve tooth structure retention and resistance to forces structure durability - enough bulk marginal integrity Preserve periodontium - easy to clean as has smooth margins Aesthetics
what is Ante’s Law
Refers to replacing teeth in perio patients
The Combined perio area of abutment should be equal to or greater than the area of the tooth replaced
What is the strength of hydrogen peroxide used in whitening?
6 %
10-15% in carbamide peroxide
What bleaching agent is used in tooth whitening?
Hydrogen peroxide is the active agent
Exists as carbamide peroxide in tooth bleaching.
What is the first treatment for tooth discolouration?
HPT
How could you do a temp for a veneer prep?
Spot bonded composite
only a middle spot etch + bonded so restoration can be flicked off
veneer prep may not need a temp
Indications for use of an inlay?
Occlusal cavities
Inter-proximal cavities (typical MO or DO)
To replace failed restorations
Why use temporary filling materials?
Improve aesthetics of prep Improve occlusal function Prevent sensitivity Prevent microleakage Confirm adequate tooth prep Maintain coronal seal
What to tell pt regarding fixed pros - informed consent?
Invasiveness/reversibility of Tx Longevity and success possible complications The time involved and cost any alternative Tx options
What does “chroma” refer to in the shade of indirect restoration?
The intensity of the colour
What are rotation and translocation movements?
Both mandibular movements:
rotation - a small amount of mouth opening (up to 2mm) condyle remains in the mandibular fossa.
Translocation - Wider opening contraction of the lateral pterygoid and disc and condyle begin to move over the articular eminence.
Worst sugar for caries?
Sucrose
Purpose of a facebow?
to record the relationship o the upper arch to the condyles
What is the terminal hinge axis?
Axis of rotation of the mandible when condyles are in the articular fossa.
What are functional cusps?
Cusps that occlude with opposing teeth in ICP
palatal cusps of the upper molars
Buccal cusp of the lower molars
What is a mutually protected occlusion?
Canine guidance causes posterior disclusion on lateral extrusion. No non-working side contacts.
How to. examine pt occlusion?
Articulating paper
static occlusion - tap teeth
dynamic occlusion - lateral movement
