Regeneration and Advanced Surgery (Sabatini) Flashcards
What is the most common cause of alveolar bone defects?
Tooth loss
What are 5 causes of alveolar bone defects?
- Tooth loss
- Infection
- Trauma
- Congenital defect
- Pathology
What is the term for the loss of osseous volume with a resultant soft-tissue and bone deficiency?
Alveolar ridge resorption
What is the order of alveolar bone loss following tooth extraction?
- Buccal
- Lingual
- Palatal or crestal
The Abrams study in 1987 found alveolar ridge defects in how many partially edentulous anterior ridges?
91%
What was the most common alveolar ridge defect found int he 91% of alveolar ridge defects in the Abrams study of partially edentulous anterior ridges?
Combination of height and width deficiency
Carlsson and Persson studies found that 90% of all ridge resorption is due to tooth loss and what percentage was vertical resorption and width resorption and their respective time frames?
- Vertical ridge resorption within 2-4 months in 34-55%
2. Ridge width resorption within 1-3 years in 25-90%
The Bartee study showed that bone loss was accelerated in what time period after tooth loss?
1st 6 months
What s the name for the ridge defect classifications?
Seibert class
What is the Seibert classification of a buccolingual defect (width of bone only)?
Seibert Class I
What is the Seibert classification of a buccolingual defect (width of bone only)?
Seibert Class I
What is the Seibert classification of a combination of both buccolingual and apicocoronal ridge defects?
Seibert Class III
Is regeneration of the alveolar ridge the same things as guided tissue regeneration (i.e. regeneration around a tooth)?
No
What are 2 general materials for guided bone regeneration?
- Bone Graft
2. Membrane
What is the purpose of the bone graft in guided bone regerneation?
Provides a scaffold for cells and vessels to grow into and eventually resorb the graft
What is the purpose of the membrane over the bone graft in guided bone regeneration?
Allow fluids / serum into the graft but block out fast growing epithelial and connective tissue fibroblasts that would crowd out the slower growing bone
What are 3 general types of particulate bone graft options?
- Autografts (donor is self)
- Allografts (donor is the same species)
- Xenografts (donor is a different species)
What are 2 allograft types?
- Decalcified freeze-dried bone allograft (DFDBA)
2. Freeze-dried bone allograft (FDBA)
What is an allograft that contains bone morphogenic proteins (BMP) ansis used more around teeth?
Decalcified freeze-dried bone allograft (DFDBA)
What is an allograft that is used for ridge augmentation because it has more mineralized content which is better for guided bone regeneration?
Freeze-dried bone allograft (FDBA)
What are 2 general types of membranes used to cover the particulate bone graft for guided bone regeneration?
- Nonresorbable
2. Resorbable
What is an example of a non-resorbable membrane?
PTFE Teflon
What resorb able membranes are used at VCU?
Porcine and bovine collagen
What are 6 general requirements for guided bone regeneration?
- Blood Supply
- Osteoblasts
- Confined space
- Space maintenance
- Stabilization
- Wound coverage
What is a method to stimulate a blood supply for guided bone regeneration?
Curettage or create blood flow with a bur
What wound coverage is desired for guided bone regeneration?
Primar closure
What are 2 techniques for treatment of the edentulous ridges?
- Alveolar ridge preservation
2. Alveolar ridge augmentation
When is alveolar ridge preservation indicated?
When teeth come out
When is alveolar ridge augmentation indicated?
When damage has already been done
What are synonyms for alveolar ridge preservation?
- Socket preservation
2. Alveolar ridge maintenance
What is the term for placement of osteoconductive material in extraction sites to MAINTAIN the physiologic and anatomic integrity of alveolar bone?
Alveolar ridge preservation
What is the surgical grafting procedure designed to CORRECT deformed alveolar ridges by restoring lost bone?
Alveolar ridge augmentation
An anterior socket indicates which surgery: alveolar ridge preservation or alveolar ridge augmentation?
Alveolar ridge preservation
When would alveolar ridge preservation be indicated in the posterior?
When the socket is to be restored with implants
What is a key area preserved in atraumatic tooth removal that aides in alveolar ridge preservation?
Buccal plate
What graft material is used for socket preservation during alveolar ridge preservation: DFDBA or FDBA?
FDBA
What is the main goal of alveolar ridge preservation in extraction sites?
Protect the buccolingual width
What are 2 ways to augment an alveolar ridge?
- Soft-tissue
2. Bone graft
What dictates what is used for the alveolar ridge augmentation?
Restorative plan (e.g. is the ridge going to hold an implant or support an FPD)?
What are 2 types of soft tissue ridge augmentation techniques?
- Onlay graft
2. Connective tissue graft
What must be first created for a soft tissue onlay graft?
Bleeding bed
What is the normal soft tissue graft type?
Autograft
Is the onlay graft a predictable procedure?
No. It depends upon the body to fully invade and vascularize
What is a graft wherein a pouch is created (split-thickness flap) and a tissue graft is slid in to plump it out)?
Connective tissue graft (CT graft)
What is an advantage of the non-resorbable titanium reinforced membrane for alveolar ridge augmentation?
Allows bending of membrane
What are 2 types of bone graft materials?
- Particulate graft
2. Block graft
What are the 2 most common block graft donor sites?
- Chin graft
2. Ramus graft
Is regenerated bone as good as non-regenerated bone?
Yes
What is an indication for a maxillary sinus lift?
Not enough bone between the crest of the ridge and the floor of the sinus to hold a minimum 10mm implant
What do maxillary sinus lifts have an increased risk for?
Infection
What are 2 ways to perform a maxillary sinus lift?
- Lateral window technique
2. Osteotome technique
When performing a maxillary sinus lift by either the lateral window technique or osteotome technique, is the surgeon going into the sinus?
No, the sinus is lifted up and bone is placed underneath
What is the term for the formation of new bone, new cementum, and new periodontal ligament about a tooth root surface previously exposed to bacterial plaque?
Regeneration
What has been removed and what remains in demineralized freeze dried bone allograft material?
Calcium ions are removed but bone morphogenic proteins remain, which are thought to stimulate the body to produce bone
The Melcher study listed what 4 compartments of the periodontium?
- Gingival corium
- PDL
- Cementum
- Bone
Of the cells of the periodontium, which are the only ones that have potential for regeneration according to the Melcher study?
PDL cells. They can differentiate into any of the other cells.
The early perspective for bone grafts was to get what? In the 1970s that changed to what?
Bone fill. Changed in the 1970s to regeneration of periodontal apparatus
Bone grafting techniques should focus on what?
Selecting cell populations
What cell populations should be excluded from a bone graft?
- Epithelial cells
2. gingival connective tissues cells
What cell populations should be included in a bone graft?
PDL and bone cells
What is the key to bone regeneration when placing a bone graft?
The membrane (came about in 1982)
What is the use of barrier membrane to select for the cell types that will result in periodontal regeneration?
Guided tissue regeneration
What is a big name for expanded Teflon membrane that is non-resorbable and is the cornerstone of guided tissue regeneration?
Polytetrafluoroethylene (PFTE)
What does the pore size do in PFTE barrier membranes in guided tissue regeneration?
Allow nutrients in but block out undesired cells
If a barrier is important, why put bone graft in the defect and then cover it with the barrier? Why not just place a barrier with no graft?
- The bone graft is a scaffold for in-growth of vessels and cells
- Barrier to epithelial and CT cells from the flap
- Maintain space beneath the flap
- May stimulate new bone growth
When considering the anatomy of the defect, what defect has the higher chance of success for guided tissue regeneration?
Defect with multiple walls (e.g. 3 wall defect)
How do you determine the number of walls of a defect?
Imagine arrows coming from the bone into the defect (e.g. 3 wall defect would have arrows coming in from the wall formed by the buccal plate, the wall formed by the lingual plate, and the wall formed by the bone attached to the adjacent tooth. The floor of the defect is not considered a wall).
What are the types of boney defects around a tooth?
1 wall 2 wall 3 wall Combination Circumferential
Which defect has a 95% success rate for regeneration with guided tissue regeneration?
3 wall
What are 3 things that increased the regenerative potential in a defect?
- Number of walls
- Deeper defect better
- Narrower defect better
Can horiztonal bone loss be regenerated through guided tissue regeneration?
No, only intra-osseous defects
Can guided tissue regeneration be done in furcations?
Yes. Grad II ideal
What furcations are not ideal for guided tissue regeneration?
Grade III
Grade IV
Which arch furcation (maxillary or mandibular) is more favorable for GTR and why?
Mandibular due to easier access
What furcation on a maxillary molar is more favorable for GTR and why?
Maxillary buccal
Is GTR indicated with an osseous defect that is more vertical or horizontal?
Vertical
Is GTR indicated with a Grade II or Grade III furcation?
Grade II
Is GTR better when there is more or less gingival recession?
Less gingival recession
Is GTR better when the width of keratinized gingiva is wide or narrow?
Wide
Is GTR better when the gingival thickness is thick or thin?
Thick
Is GTR better when the interdental space is wide or narrow?
Wide
Is GTR better when the tooth is more or less mobile?
Less mobile
Is GTR better when the patients oral hygiene is good or poor?
Good
What are 5 ideal membrane properties for GTR?
- Maintain space
- Porous
- Occlusive to cells
- Biocompatible
- Resorbable
The majority of resorb able membranes are of what material?
Collagen of porcine or bovine origin
Is there a resorb able membrane that has Gore in the name that could be confused with a non-resorbable Goretex membrane?
Yes. Gore Resolut XT resorbs in 8-10 weeks
What is a flowable liquid that sets with water spray to form a resorbable barrier membrane that resorbs in 5-6 months?
Atrisorb
Resorbable xenograft barrier membranes resorb in what time frame?
4-8 week to 4-6 months
What bone graft material contains live cellular elements capable of new bone growth (e.g. osteoblasts in an autograft from the patient’s iliac crest)?
Osteogenic
What bone graft material contains elements capable of stimulating host tissues to produce new bone (e.g. bone morphogenic proteins in DFDBA)?
Osteoinductive
What type of bone graft material provides a “scaffold” to support new bone growth?
Osteoconductive
Does osteoconductive bone graft material have any biologic activity?
No
What is a graft that is from you?
Autograft
What are disadvantages of an autograft?
- Lack of sufficient bone
2. Secondary surgical site
Which one is an autograft: osteogenic, osteoconductive, osteoinductive?
All 3: osteogenic, osteoconductive, osteoinductive
What is a graft that is from someone of the same species?
Allograft
Of the 2 allograft types, demineralized freeze-dried bone allograft (DFDBA) or freeze-dried bone allograft (FDBA) which one has more available bone morphogenic proteins?
DFDBA
Allografts are which one: osteogenic, osteoconductive or osteoinductive?
Osteoconductive and osteoinductive
What type of bone graft material is generated in a lab (ceramic compounds, calcium sulfate, bioglass, hydroxyapatite) that are biocompatible, but lack osteoinductive potent ion (only osteoconductive)?
Alloplasts
What bone graft material is from cows, pigs, and coral?
Xenograft
Xenografts are which of the 3: osteogenic, osteoconductive, or osteoinductive
Osteoconductive
What are 3 options for particulate bone graft material in GTR?
- Autografts (osseous coagulum)
- Allografts (DFDBA or FDBA)
- Xenografts
What is a new GTR material compound of enamel protein amelogenin from the tooth buds of fetal pigs (has been used to treat vertical boney defects and increase attachment in horizontal bone loss)?
Emdogain
What are 3 ways it is thought Emdogain might accelerate wound healing?
- Stimulates proliferation of PDL cells
- Inhibits periodontal pathogenesis (actinobacillus actinomycemcomitans; porphyromonas gingivalis, prevotella intermedia)
- Stimulates angiogenesis
What are 6 growth factor molecules attached to bone graft particles that aide in regeneration?
- BMP (bone morphogenic proteins)
- TGF-Beta (transforming growth factor)
- PDGF (platelet derived growth factor)
- IFG (insulin-like growth factor)
- FGF (fibroblast growth factor)
- EMD (enamel matrix derivative ((emdogain))
