Periodontology Flashcards
1
Q
What is an acquired pellicle?
A
The acquired pellicle is a biofilm, free of bacteria, covering oral hard and soft tissues. It is composed of mucins, glycoproteins and proteins, among which are several enzymes.
2
Q
How long does it take for the acquired pellicle to form?
A
Seconds to minutes.
3
Q
What are the different stages/phases of formation of plaque?
A
- Formation of an acquired pellicle
- Planktonic bacteria approach surface
- Contact and attachment of other bacteria
- Adherance and changes in cell surface
- Metabolic activity changes environment
- Quorum sensing and development
- Mature biofilm can seed new planktonic cells into the environment.
4
Q
What is the bacteria that normally finds first to the acquired pellicle?
A
Streptococci
5
Q
How to bacteria bind to the tooth surface/acquired pellicle?
A
Ionic bonds form between the calcium on the tooth surface and the negatively charged bacteria cell walls.
6
Q
What strain of streptococci is leading bacteria for dental decay?
A
Streptococcus mutans
7
Q
What do early colonisers such as streptococci provide to help the formation of plaque?
A
Early colonisers change the environment, offer sites of attachment for other bacteria and produce environments for gram negative and anaerobic bacteria.
8
Q
Describe the difference in bacteria from supragingival plaque to subgingival plaque
A
Supragingival - Majority is gram positive although still contains gram negative bacteria more apically. High in gingivla crevicular fluid.
Subgingival - Majority is gram negative bacteria. At base of sulcus/pockets are rows of spirochaetes at right angles to the enamel and cementum.
9
Q
Name the 3 bacteria that form the red complex.
A
- Porphyromonas gingivalis
- Tanerella forsythia
- Treponema denticola
10
Q
What colours will stain gram positive and gram negative bacteria?
A
Gram positive - stain purple
Gram negative- stain pink
11
Q
What toothbrushing technique is demonstrated in oral hygiene demonstrations?
A
Bass technique
12
Q
What does TIPPS stand for?
A
talk
interact
practice
plan
support
13
Q
What is loss of attachment?
A
Loss of attachment is when the base of the pocket is apical/below the amelocemento junction: i.e on the root surface.
14
Q
What is false pockets?
A
Base of pocket is above ACJ - no LOA.
15
Q
What % of damage in periodontitis is due to the host response to the invading bacteria?
A
80%.
16
Q
What are the 3 types of anaemia?
A
Microcytic - low iron
Macrocytic- B12, folate, pregnancy, drug related (methotrexate)
Normocytic - leukaemia, renal failure, infection, malignancy.
17
Q
What are some dental findings of anaemia?
A
Angular chelitis
Recurrent oral ulceration
Candidiasis
Glossitis
Burning mouth syndrome
Mucosal Pallour
18
Q
What is neutropenia?
A
Low white blood cells (neutrophils)
19
Q
What are some dental findings of neutropenia?
A
Candidiasis
Recurrent oral ulceration
Herpes Simplex Virus
Neutropenic Ulceration
May worsen periodontal disease
19
Q
What is lymphoma?
A
Malignant transformation of B or T cell lymphocytes.
Can be Hodgkins or Non-Hodgkins.
20
Q
What is leuokaemia?
A
A type of blood cancer that affects blood cells in your bone marrow.
Classified by cell of origin (lymphoblast or non-lymphoblast)
Cell maturity immature (acute), mature (chronic)
21
Q
What are some general rules for flap design?
A
Dont cut on maximum bulbosity of root
Dont cut diagonal relieving incisions
Flap should always be broader than it is long
Dont cut vertically through a papilla
22
Q
What type of sutures are now commonly used in periodontal surgery?
A
- Now use synthetic mono-filament suture
- Resorbable or non-resorbable
- Non-wicking
- Low bacterial colonisation
- Can be difficult to tie as “springy”
23
Q
What are 3 types of periodontal surgery?
A
- resective
-repair
-regenerative
24
What is resective surgery?
Pocket elimination procedures which establish a morphologically attachment but with apical displacement of the dento-gingival complex
25
What are examples of resective surgery?
-gingivectomy
- apically repositioned flaps
- root resection
- osseous reduction
- distal wedge incision
26
What is repair/reattachment surgery?
pocket reduction surgery, but without replication of the normal attachment
in other words, healing is by formation of the long junctional epithelium.
- Normally managed with partially reflected flaps.
27
What are the aims for partially reflected flaps in repair surgery?
- access for RSD under direct vision
- assessment of root surface
28
What are the 2 types of partially reflected flaps?
- open flap debridement
- Modified Widman flap
29
Describe the procedure for open flap debridement.
1. Patient consent and LA
2. 1min chlorohexidine mouth rinse and pre-operative preparation
3. Incision in gingival sulcus to allow access to pathological pocket
4. Raise full thickness flap, limited to 1mm below alveolar crest
5. Removal of granulation tissue from site
6. Scaling of tooth surfaces under direct vision
7. Closure with sutures
30
Describe the Modified Widman Flap.
Involves resection of soft tissue collar from gingival margin. Incision 0.5-1mm from gingival margin.
31
Name some indications for partially reflected flaps.
Excellent maintenance
Site >6mm or equal to with BOP or suppuration
Horizontal bone loss pattern
Vertical defect less than 3mm
Isolated periodontal pockets remain
32
Name some contra-indications for partially reflected flaps.
Aesthetic region
Need for graft/membrane
Complex furcation/bone defects
Lack of/limited attached gingivae (MWF)
33
Name some advantages for partially reflected flaps
- Healing by primary intention
- Minimal crestal bone resorption
- Effective in pockets 6-7mm
34
Name some disadvantages for partially reflected flaps
- Can be unpredictable (dependent on healing potential)
- No new attachment (healing by long junctional epithelium)
- Risk of recession
- Interdental craters
35
What is regeneration?
Recreation of the complete attachment apparatus of bone/cementum functionally orientated periodontal ligament against previously exposed root surface
36
What are some differences in repair versus regeneration?
Repair:
- long junctional epithelium
- Crestal remodelling
Regeneration:
- New cementum
- New PDL
- New alveolar bone
37
What are the aims of regeneration surgery?
- Regenerate defect (gain clinical attachment, minimise soft tissue recession, increased bone volume)
- Remove factors associated with disease progression (residual deep sites, infrabony defects, furcation involvement, BOP)
- Enhance access for plaque control and maintenance.
38
What 4 things are needed for regeneration?
PDL cells
Wound stability
Space provision
Primary intention healing
39
What is the case selection that is required for regeneration surgery.
- Infrabony defect associated with a periodontal pocket >6mm
- depth of vertical defect >3mm
- Narrow defect <25 degrees ideally
- Higher number of bony walls
- Class II furcation in mandibular molars
- Single class II furcation in maxillary molars
*True anatomy only revealed during surgical procedure*
40
What are 4 regeneration techniques?
1. Guided tissue regeneration
2. Bone graft material
3. Enamel matrix proteins
4. Combinations (GTR and bone)
(EMD and bone)
41
What is Guided Tissue Regeneration (GTR)?
Use of mechanical barrier to selectively enhance the establishment of PDL and peri-vascular cells in osseous defects to initiate periodontal regeneration.
42
What are 3 aims in GTR
- stop rapid downgrowth of epithelial cells
- Create space for pluripotent cells from PDL to access root surface
- Improve local anatomy, function and prognosis of teeth
43
What is the purpose of a membrane in regeneration surgery?
Act as a barrier to prevent cells apart from PDL migrating into site.
Provide "space" for regeneration
Promotes PDL cells for regeneration
44
What are the different sources of bone grafts?
Autograft: from a donor site of same person
Allograft: from a different person but human bone
Xenograft: from an animal source
Alloplast: synthetic material
45
What is Emdogain?
Emdogain (EMD) mimics the development of tooth supporting appartus during tooth formation
- 90% amelogenins (cocktail of proteins)
- propylene glycol alginate (PGA)
Accelerates wound healing
Direct effects on cellular behaviour to promote regeneration.
46
What effect does emdogain have on epithelial cells?
Decreased cell proliferation and migration
47
What effect does emdogain have on gingival fibroblasts?
Reduced cell migration
48
What effect does emdogain have on bone?
Increased cell proliferation and migration, support of bone formation but not osteoinductive
49
What effects does emdogain have on PDL fibroblasts?
Increased cell proliferation, migration and attachment q
50
What effects does emdogain have on cementoblasts?
Increased in vivo mineralisation
51
Describe the regeneration procedure.
1. Patient consent and LA
2. 1min chlorohexidine mouth rinse and pre-operative preparation
3. Incision in gingival sulcus to allow access to pathological pocket
4. Raise full thickness flap, limited to 1mm below alveolar crest
5. Removal of granulation tissue from site
6. Scaling of tooth surface under direct vision
7. Place membrane/graft/EMD or combination into defect
8. Closure with sutures
52
What combination technique has best combination for non-contained defects?
GTR and graft.
53
What are some advantages of regeneration?
- Successful in treatment of deep sites of 6mm or greater
- Healing by primary intention
- Improvement in volume of supporting tooth tissue
- less recession for patient
54
What are some disadvantages of regeneration?
- technically challenging to get good outcome
- Can be unacceptable for some patients depending on the material used
- Expensive materials
55
What is gingival overgrowth?
- Abnormal overgrowth of gingival tissues
- Multiple causes: inflammatory, drug-induced, related to systemic conditions.
Can be localised or generalised
56
Describe a gingivectomy
Management of gingival overgrowth by resection/recontouring of the gingivae.
Radical procedure. Rarely used in treatment of periodontitis now.
Leaves raw wound, healing by secondary intention (0.5mm re-epitheliasation per day)
Use periodontal dressing pack (Coe-pack) to cover 7-14 days.
57
What are some indications for a gingivectomy?
Gingival enlargement/overgrowth persists despite non-surgical care.
Supra-bony periodontal pocketing
Excellent at home care
Wide zone of attached gingivae
58
What are some contraindications of a gingivectomy?
Narrow attached gingivae
Planned osseous recontouring
Infra-bony periodontal pockets
Medical contra-indications; esp bleeding disorders
59
What are some advantages of a gingivectomy?
- Simple
- Good vision
- Can achieve ideal soft tissue morphology
60
What are some disadvantages of a gingivectomy?
- Limited indications
- Heal by secondary intention
- Risk bone exposure
- Wastes attached ginigvae
- Excessive recession in PDL (aesthetics, sensitivity, root caries, abrasion).
61
What is surgical crown lengthening?
A surgical procedure, which apically repositions the soft tissue and alveolar bone to expose more tooth structure, and increase the length of the clinical crown.
Normally a resective procedure depending on the amount of attached gingivae available
62
What is the overall aim in surgical crown lengthening?
Surgically maintain the biologic width whilst apically repositioning the gingival level.
63
What are some indications of surgical crown lengthening?
1. Toothwear
2. Poor gingival aesthetics
3. Restoration of subgingival lesions
4. Replacement of crown with deep margin
5. Management of coronal third fractures
6. Management of infringment of biological width
7. Develop ferrule for pulpless teeth restored with posts.
64
What are some contra-indications for surgical crown lengthening?
1. Poor plaque control
2. Poor compliance
3. Non-functional teeth or teeth with poor strategic value
4. Periodontal destruction
5. Endodontic compromise
6. Medical history considerations
65
What are some complications of surgical crown lengthening?
- Poor aesthetics due to black triangles
- Transient mobility of teeth
- Root sensitivity
- Rebound of marginal tissues
- Root resorption
66
What are some treatment options when there is furcation involvment?
1. Non-surgical periodontal therapy (class 1)
2. Odontoplasty (class 1 and 2)
3. Open flap debridement (class 2)
4. Tunnelling procedures (class 3)
5. Root resection or separation
6. Regenerative procedures (class 3)
7. Extraction
67
What is an odontoplasty?
Reduces plaque accumulation by reshaping tooth surface with a bur. Can aid in treatment of grade 1 and shallow grade 2 lesions
Surgical procedure involving raising a flap buccal and lingual to the site
Can result in hypersensitivity and caries
68
What is tunnel preparation?
- Used in mandibular molars with deep degree 2 and degree 3 lesions
- Aims to improve ability for oral hygiene measures
- Can only be done with wide furcation entrances (most likely with mandibular molars).
69
Describe the tunnel procedure.
Buccal and lingual flaps raised
Granulation tissues removed and RSD
Furcation widened by enough bone removal to allow access for cleaning between roots post-operatively
Flaps apically repositioned
70
What are the increased risks for tunning procedures?
- root caries
- sensitivity
- loss of vitality
71
What is root resection?
Removal of one root of a multi-rooted tooth where there is uneven bone loss
72
What are the indications of root resection?
Class 2/3 furcation involvement
Severe bone loss on 1 or more roots
Root fracture/perforation/deep caries
Failed endodontic treatment of inoperable canals
73
What are some contra-indications of root resection
- Inadequate bone support on remaining roots
- Unfavourable anatomy (fused roots, long root trunk)
- Significant discrepancies in bone height
- Remaining roots not restorable
74
In what roots does root resection have a higher success with?
Better success with MB,MD maxillary molars
Mesial roots of lower molars
75
What are some aetiology factors of recession?
- Traumatic e.g toothbrushing, traumatic overbite, periodontal disease, poor restorative margins
76
What factors put patients at high risk of recession?
High muscle attachment/frenal pull
Thin tissue phenotype
Alveolar dehiscence
Teeth outside alveolar bone after orthodontic treatment
Lack of keratinised tissue
77
What are some non-surgical interventions for recession?
- monitoring and prevention
- composite restorations
- gingival prosthesis
- orthodontics
78
What are some surgical interventions of gingival recession?
- Frenectomy
- Pedicle flaps
- Free gingival flaps
- subepithelial connective tissue graft
- coronally advanced flap and GTR
79
What are some indications for surgical management of recession.
- prevention of continued recession
- improve ability to perform OH measures
- Aesthetic concern
- Sensitivity?
- Root caries?
80
What are some contra-indications for surgical management of recession?
- Poorly controlled diabetes
- Bleeding disorders
- Smoking
- Poor OH
- Active periodontal disease
- Previous failed procedures
- Self inflicted injuries
81
What are some indications for a frenectomy?
- unstable local tissue (movement, blanching on retraction)
- Blocking access for OH measures
- Non recession indications (midline diatema in ortho, shallow vestibule for prosthesis).
82
What are some contra-indications for a frenectomy?
Medical/bleeding disorders
Scar formation will make further procedures more challenging
83
What is a pedicle flap?
Moving adjacent attached gingivae to cover a region of recession using a split thickness flap
Can be laterally repositioned or double pappilla
84
What are some indications for a pedicle flap?
- Narrow defect on single tooth
- Adjacent teeth with thick phenotype or edentulous area
- Deep vestibule
85
What are some contra-indications for a pedicle flap?
- deep periodontal pocketing
- Loss of interdental tissue
- Large root prominences
- Lack of relevant local anatomy
- Deep root abrasion
86
What are some advantages of a pedical flap?
- one site surgery
- Good vascularity to pedicle flap
- root coverage possible
87
What are the disadvantages of a pedicle flap?
- limited by amount of adjacent keratinized , attached gingivae.
- Risk of recession at donor site
- Risk of dehisense at donor site
- Limited to a single tooth
- Not as likely to gain root coverage.
88
What is a free gingival graft?
Graft from palate formed of epithelium and small amount of underlying connective tissue is placed into region with localised recession.
89
What are some indications of a free gingival graft?
- discomfort during OH measures
- on going local inflammation
- lack of keratinized tissue in region of recession defect
- prevention of further recession
- insufficient local keratinized tissue for pedicle flap.
90
What are some contra-indications for a free gingival graft?
Aesthetic region
Aim for complete root coverage
Donor site tissue poor
Medical contraindications
91
What are the advantages of a free gingival graft?
- relatively simple surgery
- increases vestibular depth
92
What are some disadvantages of gingival graft?
Second surgical site
Palatal wounds heal by secondary intention
Unaesthetic
93
What is a coronally advanced flap?
Surgical procedure where a split thickness flap is raised, released and then replaced in a more coronal position
Can be combined with a connective tissue graft from the palate, especially when:
- limited attached gingivae apical to recession
- Shallow sulcus
- buccaly placed root
- interdental CAL
94
What are some advantages of coronally advanced flap?
Possible for one site surgery
Less technically demanding than tunnelling in thin phenotype
Can be combined with GTR
95
What are some disadvantages of coronally advanced flap?
- Often benefits from CT graft
- If used with GTR, higher risk of infection
- Vertical relieving incisions mean delayed healing
96
