Soft Tissue Management Flashcards
What should be done before the crown prep
Assess the periodontal stats and give OHI
Should complete any periodontal treatment required ± surgery to ensure a healthy periodontium
Why should we ensure that there is a healthy periodontium before the crown prep
- Untreated gingivitis creates swollen, inflamed and loose gingival tissues
- Can create difficulties when assessing and preparing the finish line you want, obtaining moisture control, reproducing the finish lines in the impression
- Can result in suboptimal marginal crown fit and increase risk of further perio deterioration and caries
Why are sub-gingival preparations risky when doing a crown prep
- Difficult to do and risks marginal leakage
- Risks encroaching on the biological width leading to persistent gingival inflammation, alveolar bone loss and gingival recession
What can dictate more apically placed margins in crown prep
- Deep extensive restorations or short clinical crown height
What can be done if more apically placed margins are indicated in crown prep
Surgical crown lengthening should be considered
When is soft tissue management required in the impression stage of crown preps
If some or all of the preparation finish line are at or are sub-gingival
Why is gingival retraction (soft tissue management) needed for sub gingival preparations in the impression stage
- To prevent bleeding
- to act as a physical barrier and retract the gingival tissues?
- Allows an accurate impression of the preparation margins
What is the aim of the plain retraction cord method of soft tissue retraction
Sulcus enlargement to physically displace the gingivae away from the finish line
What is a disadvantage of the plain retraction cord method of soft tissue retraction
Sulcular haemorrhage (this method is quite shit)
Why can sulcular haemorrhage be problematic in the crown procedure
leads to moisture control difficulty and poor impression accuracy (impression materials are hydrophobic)
What is the aim of the copper band method of soft tissue retraction
To displace the gingivae and helps to carry the impression material to ensure the finish line is captured in the impression (this method is shit)
What are the disadvantages of the copper band method of soft tissue retraction
- Traumatic
- Not effective
- Not accurate
(method is shit)
What is the impregnated retraction cord method of soft tissue retraction
- Retraction cord soaked in a chemical solution
- Then its the same as the plain retraction band method
What is the aim of the impregnated retraction cord method of soft tissue retraction and what is the benefit of the chemical action
Aim = enlarge the sulcus
Chemical action = control sulcular haemorrhage creating a more accurate impression of the preparation margins
What are the disadvantages of the impregnated retraction cord method of soft tissue retraction
- Systemic side effects
- Inflammation and tissue necrosis
- Staining
What solutions are used in the impregnated retraction cord method of soft tissue retraction
- Ferric Sulphate 15%
- Alum AlK(SO4)3
- Aluminium sulfate
What does the crown lengthening method of soft tissue retraction involve
Bone removal and gingival re-contouring
What are the advantages of the crown lengthening method of soft tissue retraction
- Increases the crown height and retention
- create supra gingival margins
- Improves aesthetics
What are the disadvantages of the crown lengthening method of soft tissue retraction
- Discomfort
- Finish line on root surface cementum (bonding issues)
- Furcation involvement (cleaning)
- Increased crown:root ration
- Need to allow time for healing
What is the aim of the rotary curettage method of soft tissue retraction
The limited removal of the sulcular epithelium with rotary instruments while preparing the marginal finish line
What is the advantage of the rotary curettage method of soft tissue retraction
quick
What are the disadvantage of the rotary curettage method of soft tissue retraction
- Trauma and haemorrhage with poor healing
- Increased risk of periodontal destruction
This method is also shit and is rarely used
What is the aim of the retraction paste method of soft tissue retraction
Gingival retraction pastes can be used to create space between the prepared tooth and the sulcus
What are some of the properties of the retraction pastes used in soft tissue retraction
- Some are medicated e.g. with Aluminium Chloride
- Material is viscous and maintains rigidity, displacing the gingivae away from the tooth without causing trauma