W7 - Flap Surgery Part II - Sharma

Question 1

T/F - Teeth with furcation involvement respond more favourably to non-surgical periodontal therapy

Answer 1

False

• Teeth with furcation respond less favourably and have reduced prognosis

Question 2

What are the two surgical treatment options (big picture) for furcation involved teeth

Answer 2

Resective surgery

Regenerative surgery

Question 3

What are the two types of resective surgery offered to furcation involved pts

Answer 3

Furcation plasty

Hemi-section / root resection / bicuspidization

Question 4

3 Grades of furcation involvement

Answer 4

Grade I - Incipient, catch

Grade II - Bone loss, not through and through, “cul de sac”

Grade III - bone loss through and through

Question 5

What affects the perio pocket in a furcation lesion (anatomy) (3)

Answer 5

• Anatomy of the soft tissue (thick, thin?)
• Bone - horizontal or angular loss
• Inter-radicular tooth anatomy

Question 6

What does a furcation plasty involve? What is the purpose/outcome?

Answer 6

Odontoplasty

Osteoplasty

Gingivoplasty

Purpose is to improve access for pt to clean

Question 7

Technique of furcation plasty

Answer 7

1. Flap to access inter-radicular area
2. Odontoplasty to widen furcation entrance
3. Osteoplasty to reduce intra-bony defect and decrease thickness of the bone
4. Position the flap at the level of the alveolar bone crest

Question 8

Why should aggressive odontoplasty for furcation plasty be avoided on vital teeth?

Answer 8

Risk of hypersensitivity

Question 9

Answer 9

Furcation plasty

• non surgical therapy did not help
• Exposed the furcation for better cleaning

Question 10

What is a tunnel preparation? Purpose?

Answer 10

Exposing / clearing the furcation in deep grade II and III FI teeth

• Md molars only - mx molars will have palatal root in the way
• Allows for easier cleaning
• Delays the need for extraction

Question 11

What is the rationale behind hemi-section, root-resection and bicuspidization?

Answer 11

Complete elimination of the furcation defect

• Multidisciplinary approach (endo and restorative)
• Endo usually done before surgery

Question 12

What is going on here?

Answer 12

Hemi section

• Sectioning of tooth into two and removing half of it
• Remove the root where endo has failed
• Typically mesially half is extracted

Question 13

What is a root resection?

Answer 13

Removal of one or two roots

• only done in the mx teeth

Question 14

Technique of root resection and hemisection

Answer 14

1. Create mucoperiosteal flap to expose furcation
2. Sectioning of root or tooth with straight line cut
3. Careful removal of root (root resection) or tooth section (hemisection)
4. Re-positioning of the flaps at bone crest level

Question 15

Outcome of root resection / hemisection

Answer 15

Remaining root(s) have improved/adequate bone support

Good prognosis if endo therapy and occlusion is sound

Question 16

Why do root rections / hemisections most often fail?

Answer 16

Failures are usually due to endo complications and/or occlusion issues

• Not usually due to periodontal complications

Question 17

Answer 17

Bicuspidization

• splitting the tooth into two and retaining both sections

Question 18

Technique of bicuspidization

Answer 18

1. Mucoperiosteal flap to expose furcation
2. Section of tooth with straight line cut
3. Re-position flaps at level of the bone crest

Question 19

What is regenerative surgery?

Answer 19

Formation of new cementum, PDL and bone that was destroyed by periodontal disease

Question 20

How can you confirm regeneration?

Answer 20

Cannot verify true regeneration without removing tooth and surrounding bone for histological evaluation

Decreased pocket depth may suggest it however this could just be due to tightly adapted gingiva with long junctional epithelium

Question 21

What 4 tissues can fill the space after flap surgery

Answer 21

Epithelium (most common)

Connective tissue

Bone

PDL

Question 22

What are the indications for bone grafts (4)

Answer 22

1. Infra/intra bony defects (three and two walled) - vertical or angular BL
2. Grade II furcation
3. Preparation of implant placement site
4. In combination with GTR (tissue regeneration)

Question 23

What is GBR and GTR?

Answer 23

Guided Bone Regeneration

Guided Tissue Regeneration

Question 24

Contra-indications for bone grafts (4)

Answer 24

• Horizontal bone loss (no walls to give support - physical and vascular)
• Lack of soft tissue coverage
• Poor OH / plaque control
• Systemic issues - smoking and poor general health

Question 25

Rank the 4 types of graft materials from best to worse

Answer 25

1. **Autogenous graft** * From self - Retromolar area if small, hips or ribs if large 1. **Allograft** * From other humans 1. **Xenograft** * From animals 1. **Alloplast** * Synthetic

Question 26

# Define osteogenic bone graft Example?

Answer 26

Graft which can: **provide the appropriate cellular elements** which survive transplantation and **synthesize new bone** at the recipient site Example: autografts

Question 27

Define osteoinductive bone graft

Answer 27

Grafts that send signals to attract, proliferate and differentiate cells capable of forming bone Ex - allograft

Question 28

Define osteoconductive graft

Answer 28

Graft that serves as a scaffolding that bone cells can attach to and grow/divide Ex. allografts and xenografts

Question 29

Why are autografts considered the “gold standard” of graft materials (4)

Answer 29

Most compatible Can pick shape - blocks or chios Multiple sites - intra oral/extra oral Forms new bone

Question 30

Pros and cons of harvesting autografts from **extra-oral** sites Locations?

Answer 30

Pro: can take out larger quantities Cons: -increased morbidity (need GA), -theatre cost Common sites: Iliac crest (hips), ribs, fibula, tibia

Question 31

Pros and cons of harvesting autografts from **intra-oral** sites Locations?

Answer 31

Pros: lesser morbidity **(under LA)** Cons: -**limited** quantity (smaller) -surgical expertise Possible sites: Extraction sites, md retromolar area, ramus, tuberosity, tori

Question 32

What tool is used to remove chips of/from bone for grafts

Answer 32

Bone scraper

Question 33

2 Types of allograft materials

Answer 33

Freeze dried bone (FDB) Decalcified Freeze dried bone (DFDB)

Question 34

What is “Selective Repopulation”

Answer 34

Type of GTR Placement of membrane allows for selective repopulation of space - blocks off the epithelium and connective tissue - only allows PDL and bone to fill space

Question 35

What are the only two ways of obtain bone regeneration in the mouth

Answer 35

1. Bone grafts 2. GTR - Selective repopulation

Question 36

What's going on here?

Answer 36

Selective Repopulation

Question 37

What are non resorbable membranes used for? (selective repopulation) Disadvantages?

Answer 37

GBR * requires second surgery to remove * If not covered with soft tissue, can lead to infection

Question 38

2 Examples of nonresorbable membranes

Answer 38

Goretex Cytoplast

Question 39

3 Examples of resorbable membranes Advantage?

Answer 39

Collagen (Bio-Gide) Polylactic acid Polyglycolic acid

Question 40

Advantages of resorbable membranes (4)

Answer 40

Second surgery for removal not necessary More tissue-friendly Enhance tissue coverage Resist or prevent microbial colonisation (infection)

Question 41

Disadvantages of resorbable membranes

Answer 41

May elicit immunologic or inflammatory reaction Time of resorption can't be controlled

Question 42

What is “socket preservation”

Answer 42

GBR usually done to allow for bone regeneration for implant placement * Use of non-resorbable membranes at exo site