Chapter 4 B: Cavity Restorations General Concepts Flashcards
A restoration is
Any filling, inlay, … that restores or replaces lost tooth structure, teeth, or oral tissues
Loss of tooth structure is caused by?
The professional while preparing cavities, except:
1. Wearing
2. Dental diseases (enamel hypoplasia)
What are factors that affect the decision to replace a tooth?
- Tooth factors
- Patient factors
- Clinician and restoration to be used factors
Tooth factors:
- primary or permanent
- occlusal stresses
- quality of the tooth (hypoplasia)
- location of the tooth
- type of tooth
- type of tooth preparation
General patient factors:
- age
- patient’s exposure to fluoride
- xerostomia
- socio-economic status
- diet
- caries status
- general health
- presence of any parafuncitonal habit
Clinician and restoration to be used factors?
- type of restoration
- physical properties of the restoration
- whether moisture control can be achieved or not
- technical expertise
Types of restorations?
(5):
1. According to the location in the crown
2. According to the material used
3. According to the insertion technique
4. According to the durability
5. According to the aesthetics
According to the location in the crown, the restoration can be?
Intracoronal or extra coronal
Intracoronal is?
When it’s placed within a preparation made in the crown of a tooth, directly into the tooth preparation
Extracoronal is?
When it’s placed outside the tooth, uses indirect techqniue
According to the material being used: the materials used to restore teeth are:
- CR
- amalgam
- GIC
- resin-modified GIC
- compomers
- cast gold
- ceramics
According to the insertion technique, it could be ?
Direct or indirect
Direct?
Material is inserted directly into the oral cavity, and hardens after insertion
EX: amalgam, or CR
Indirect?
Prepared extraorally, need a luting material that joins the tooth and the restoration
EX: cast gold or ceramics
Direct vs indirect restorations:
Which one has a more conservative preparation?
Direct
Direct vs indirect restorations:
Which one can be done in one appointment and is directly bonded without the use of cements?
Direct
Direct vs indirect:
Which one has an easily obtained adaptation and better mechanical resistance quality?
Indirect
According to the durability, it could be?
Temporary or permanent
Which ones are considered aesthetic and which ones aren’t?
Metal fillings—> not aesthetic
CR and ceramics—> aesthetic
Aim of restorations is to be able to:
- resist masticatory forces
- reproduce the natural color of the tooth
And if they don’t—> they’re temporary
Permanent restorations should be able to:
- restore function
- resist the aggressions of mastication and oral environment
- be capable of being modelled
- opposing teeth in occlusion
- adjacent teeth for inter-proximal contact
Aim of restorations:
- to seal and adapt to the tooth permanently
- protect the remaining tooth
- prevent the tooth from fractures
- protect the periodontium
- respect the pulp’s health
What do defects in the marginal seal result in?
Penetration of fluids and bacteria between filling and tooth, causes caries and pulp pathology (micro-filtration or marginal leakage)
Characteristics of restoration materials include:
- resistance to mastication forces
- wear resistance
- solubility
- volume changes
- expansion and contraction
- elasticity
- adhesiveness
- thermal and electrical conductivity
- biocompatibility
- chemical stability
- consistency
- control of the hardening phase
- aesthetic
The wear resistance of the restoration should be?
Equal to or less than the tooth, if not it looses the ability to restore function
The solubility should be?
Minimal
The volumetric variations of the material should be?
Equal to the tooth
How does expansion and contraction occur?
By temperature changes
The modulus of elasticity must be?
As close as possible to the dental structure
Adhesiveness?
Very desirable quality, which promotes sealing and retention of the restoration
Should the restoration material be isolating or conducting?
Isolating because the transmission of heat and electricity through the filling causes discomfort
Are degradation and chemical instability desirable or undesirable?
Undesirable except in the case of amalgam where corrosion helps sealing over time
Control of the hardening phase?
Control when we wan’t the material to harden ex: CR
Color properties?
- absorption
- refraction
- light reflection
What are the phases of cavity restoration?
Insertion
Finishing
Polishing
IFP
Insertion?
- introducing the filling material into the cavity
- gradually inserted and adapted
- amalgam condensed in small portions
- CR are placed in layers and independently polymerised
- modelling
Specific instruments for the insertion technique?
- amalgam carries, composite guns, composite syringes
In the insertion phase of indirect restorations?
The insertion consists of restoration block test and cementation
The modelling phase and polishing is made in the laboratory
Modelling sets the morphology so that the restorations fulfils the functions of?
- restoring health
- appropriate function
- aesthetics
We need adequate morphology in?
Axial surfaces, buccal curvatures, and points of contacts with the adjacent teeth
When modelling we have to protect?
Gingiva and periodontium
Finishing?
- trim excess material
When are amalgams trimmed?
Before polishing, with manual trimmers while the material is still in it’s plastic state
When are composites trimmed?
After polymerisation, with rotary instruments
The final step to achieve a smooth, sparkly, and spotless surface is?
Polishing
After polishing the surface ?
Shouldn’t retain plaque and should reflect the light uniformly
What do we have in an unpolished surface?
- increased bacterial colonisation
- alterations in areas near the gingiva as gingivitis and periodontitis
- it can cause halitosis
How can the plaque deposited on the surface change the color?
Because of pigmentation and corrosion
Which type of bacteria can pigment restorations making them visible?
Chromogenic
Abrasion is?
Sliding a rough and tough surface on another that is softer
Abrasives are?
Substances that cause wear
What materials are used for polishing?
- finishing burs
- brushes
- felt
- diamond instruments and pastes
- paper carried abrasives
- rubber ended rotary tools
- cloth
