3/13 ChiFan_GTR

Question 1

Who is the only author that found benefit of using root conditioning in addition to EMD?

Answer 1

McLaren (Schallhorn’s daughter)

Question 2

When is a soft tissue graft indicated at 2nd stage implant surgery?

Answer 2

Bach Le (author)
Indicated if the implant is buccally positioned

Question 3

In PRP, platelets are concentrated by how much?

Answer 3

3 to 4 times higher

Question 4

What did Laurell show with regards to bone fill and CAL gain for OFD, bone graft, and GTR?

Answer 4

Laurell ‘88
Bone gain:
* OFD: 1.1mm
* Graft: 2.2 mm
* GTR: 3.1 mm

CAL gain:
* OFD: 1.5 mm
* Graft: 2.1 mm
* GTR: 4.2 mm

Question 5

For infrabony defects, how does using a membrane only compare to membrane + graft?

Answer 5

Gouldin ‘96
RCT
- To compare GTR outcome between ePTFE+DFDBA vs ePTFE alone, a 6 mo study
- NSSD between groups in PD reduction, CAL gain and % bone filled

Trejo ‘02
RCT
To compare GTR outcome between PLA membrane+DFDBA vs PLA alone, a 12 mo study
- PLA+DFDBA vs PLA: PD reduction: 3.3 vs 4.1mm; CAL gain: 2.3 vs 3.2 mm after 12 mo. Intrabony defects
fill yielded similar results between groups.
- Conclusion: Additional of DFDBA to GTR procedure did not enhance clinical outcome

Question 6

How does GTR with resorbable vs. nonresorbable membrane compare?

Answer 6

Eickholz ‘98
RCT
To compare GTR outcome with either non-resorbable (ePTFE) and resorbable (Polyglactin) barrier
- 29 pair contralateral defects including infrabony defects and CLII and III FI. Clinical parameters were
measured 12 and 24 mo post op.
- NSSD in clinical and radiographic results except for PAL-V in both groups. GTR with a resorbable membrane showed
better results in PAL-V (vertical probing attachment level) in infrabody defects.
* Resorbable (PLA membrane): 3.45 mm PAL-V versus 1.95 mm for ePTFE

Pretzl ‘08
RCT
To compare GTR outcome with either non-resorbable (ePTFE) and resorbable (Polyglactin) barrier for 10Y
- 12 pairs contralateral infrabony defects. Results were measured 12 and 120+/- 6 mo post op.
- NSSD in vertical clinical attachment gain in 10Y after Sx. 75% defects which achieved 12 mo after GTR
therapy using either type of membrane was stable for 10 years.

Note: Eickholz published a series of articles comparing non and resorbable membranes in GTR of intrabony or furcation
defects with long term f/u (5~10Y). Both membranes showed positive and stable clinical improvements over 10 years of
time. Resorbable barriers have advantages over non-resorbable: elimination of second surgery for barrier removal, more
tissue-friendly to host tissue, enhance tissue coverage, reduce barrier exposure, prevent microbial colonization (Wang
1998) and presenting better outcome if membrane exposure (Murphy 1995b).

Question 7

What is the “jumping distance”

Answer 7

Stephen Chen = 2mm
Other studies say 1.25 mm
Jumping distance is the distance that will need bone grafting to maintain the space.

Question 8

What studies show that biologics have 1) superior benefits compared to OFD alone, 2) some sign of regeneration, 3) similar results to GTR, 4) no extra benefit when added to GTR?

Answer 8

Sculean ‘08
RCT
38 pts in 4 groups: EMD, GTR, EMD+GTR, OFD with 10-year f/u and clinical parameters were evaluated at
baseline, 1Y and 10Y (no bone graft added in this study).
* OFD had the most recession (1.7mm). The EMD, GTR, EMD+GTR had ~0.7 mm recession
* Similar PD reduction for all groups (~3.5mm)
* Similar CAL gain for all groups (~3mm for EMD, GTR, EMD + GTR) but OFD had the least CAL gain (1.8mm)

Iorio-Siciliano ‘11
RCT
To compare GTR results on deep, non-contained intrabony defects (≥80% 1W, the rest was 2- to 3-W)
- 40 defects on a single root. 2 Groups: EMD vs non-resorbable Ti reinforced membrane, 12 mo f/u
- Modified papilla preservation technique or simple papilla preservation was used. No graft material used.
- In a non-contained defect, EMD cannot make space. So, to use EMD, you need to have a contained defect in order to use biologics. In non-contained defects, GTR is better

CAL gain
* GTR: 4.1mm
* EMD: 2.4mm
PD reduction:
* GTR: 5.5mm
* EMD: 2.9mm
% residual PD
* GTR: 3%
* EMD: 79.3%

Artzi ‘15
RCT
Evaluate regenerative procedures in aggressive periodontitis. 32 pts with infrabony defects.
- 2 groups: EMD+xenograft vs memb+xenograft, PD and CAL were measured up to 1Y
- Results: PD reduction after 1Y: EMD vs membrane=5.16mm vs 5.32mm; CAL gain: 5.02 vs 4.87 mm
- NSSD between groups

Koop ‘12
The treatment of intrabony defects (≥ 6mm) with EMD showed an additional gain of CAL 1.3mm compared
to OFD, EDTA or placebo, but no difference found if compared with barrier membrane
- EMD showed superior outcome compared to barrier membrane in treating furcation.

Question 9

How does PDGF affect periodontal regeneration?

Answer 9

Nevin ‘13
83 pts, 36 mo multicenter study. 3
groups: β-TCP with low (0.3mg/mL) or
high (1mg/mL) concentration of PDGF,
and without PDGF. CAL and liner bone
growth (LBG) was measured at 12, 24,
36 mo.
-Results: PDGF improved bone
formation compared to graft only.
Optimal dosage of PDGF for
regeneration is 0.3 mg/ml

Question 10

How does rh-FGF-2 affect the intrabony defect fill?

Answer 10

Kitamura ‘11
RCT
5Y RCT, 267 participants. To investigate efficacy and optimal dosage of FGF-2 in regenerative procedures in
intrabony defects.
- Defects: 2- 3W, depth 3 mm or larger. Mobility < Class II.
- Groups: 0% vs 0.2% vs 0.3% vs 0.4% FGF-2
- NSSD in CAL gain, PD reduction, BOP, gingival index, recession between each group and control, avg 2-
2.5mm improvement in CAL after 72 wks.
- Results: (1) new bone formation observed in all FGF-2 (2) no FGF-2 antibody observed-> safe

Khoshkam ‘15
To compare the outcomes of regeneration with rhPDGF-bb and rh FGF-2 for periodontal intrabony defects.
- FGF-2 showed regeneration consisting of cementum and functional Sharpey’s fiber in animal models.
- Available evidence suggested that FGF-2 resulted in significantly more defect fill in percentage but not CAL
gain.

Seshima ‘22
4Y RCT, 32 intrabony defects.
Two groups: rh-FGF-2 vs rhFGF-2+DBBM (0.3% rh-FGF2)

CAL gain:
* rh-FGF2: 2.7mm
* rh-FGF2 + DBBM: 3.5mm
Radiographic bone fill:
* rh-FGF2: 42%
* rh-FGF2 + DBBM: 62%

Results:
- rh-FGF2 with DBBM yield significant bone
filled after 4 Y
- Combinational therapy is more effective
than the sole use of biologics in deeper or
poorly- contained defect

Question 11

What is more important, the biologic or the technique?

Answer 11

Aslan: Showed that the technique is more important. Demonstrated the entire papilla preservation technique and compared with vs. without EMD. The EMD provides no additional benefit (because there is already primary closure, stability, etc of the flap.

Question 12

Does root conditioning provide any benefit? (for regeneration)

Answer 12

Dyer ‘93
8 beagles
citric acid and tetracycline
Dogs underwent GTR with dPTFE membrane. Roots were either treated with citric acid,
tetracycline or nothing. HIS analysis was performed after 6 weeks. New cementum was formed on root surfaces in all the groups.
- New connective tissue and cementum formed in “nothing” group.
- Root conditioning with either CA or tetracycline does not enhance the result of GTR

Sculean ‘06
RCT
EDTA
24 pts with infrabony defects divided in two groups: OFD+EDTA+EMD vs OFD+EMD. Clinical
parameters analyzed after 12 mo
- Both groups showed positive results in PD production (5.3 vs 5.1mm) and CAL gain (3.7 vs 3.7mm).
- NSSD between groups in terms of PD reduction or CAL gain

Question 13

What is the substantivity of EMD?

Answer 13

” about 96 hours” (says Dr. Wang)

Question 14

Who conducted a study on CTG and EDTA?

Answer 14

Barootchi et al
“Limited available evidence” - but it “appears beneficial” and “may help”.
(This is a polite way of saying it “does not help”)
Does not help root coverage; however,
EDTA helps PD reduction and CAL

Question 15

What studies examine GTR in furcations?

Answer 15

Yukna & Yukna ‘97
16 max and 10 mand molar Class II FI with regenerative therapy were re-entry at 6-12 mo post surg and f/u 6
Y. Defects were grafted with synthetic bone and CAF. Outcomes: horizontal furcation attachment level 4.4mm
to 2.0mm, vertical attachment level from 5.4mm to 4.1mm after 6 years. PD reduction from 5.4 mm to 3.2
mm at 6Y. Only 4/26 remained CL II, all the others converted in either complete closure or CL I. (survival rate
100%)

Eickholz ‘06
It was a 10 year f/u study to evaluate the long term result of GTR on FI-II defect. GTR was performed with
either ePTFE or collagen membrane Outcome: Both PD reduction and CAL gain were observed at 12mo and
10 years f/u. Horizontal attachment gain could be stable for long term after GTR on FI-II (survival rate 83%)

Question 16

(Dr. Wang bonus question): Who did Bowers mentor in the field of regeneration?

Answer 16

Mellonig - allograft
Yukna - synthetic graft
Schupfnig (?) - calcium sulfate

Question 17

In furcations, should you use GTR or just a bone graft?

Answer 17

Jepsen ‘19
Systematic review
This systematic review showed regenerative surgery for FI-II is superior to OFD (overall 1.6mm more horizontal CAL gain), and complete closure or class I conversion was expected.
Better horizontal bone level gain was achieved with bone graft alone followed by bone graft+res-m followed by EMD.
Non-resorbable membrane
with bone graft ranked as the best treatment for vertical clinical attachment gain (VCAL) and PD reduction.

Question 18

Does EMD provide better results in furcation regeneration?

Answer 18

Jepsen ‘04
- EMD vs resorbable barrier membrane (control) for mand buccal furcation
- multicenter RCT, 14 month study
- Horizontal reduction: EMD vs membrane = 2.9 vs 1.8 mm; complete closure: EMD vs membrane =18% vs 7%
- Higher H reduction, lower post-operative pain/swelling and higher complete closure rate in EMD group

Jaiswai ‘13
Regeneration with EMD+BG(DFDBA)+GTR vs BG+GTR vs OFD alone in 30 furcation CL II:
- EMD+DFDBA+GTR showed the best clinical outcomes
- Complete closure rate was higher in EMD+BG+GTR group

Peres ‘13
- EMD+ hydroxyapatite/b-tricalcium phosphate (HA/b-TCP) vs HA/b-TCP only, 30 proximal CL II furcation
defects on maxillary molars
- Horizontal bone gain avg 1.7 mm for both treatments. Both treatments had improved PD, CAL and bone filled,
NSSD between groups among these parameters.
- group with EMD showed higher % of complete closure and CLI conversion compared to the group without.

Question 19

What factors are indicated / contraindicated for GTR?

Answer 19

Cortellini ‘94 = patient compliance
Pt who were not compliant with recall appt had 50x more risk for attachment
loss between 1-4 years after surgery
- Pt who received only sporadic care lost 2.8mm of attachment at 1Y, whereas pt
who recalled every 3 mo could maintain the surgical result.
- Pt who received only sporadic care showed higher BOP, plaque and more
frequent P.g and P.i.

Cortellini ‘96a = good plaque control
GTR and root planing treated sites have same susceptibility to perio breakdown
-** If FM plaque score >10% had poorer outcomes and experienced attachment
loss over time.**
- Worst results showed in pt who had poor OH, not comply with the recall and
smoked. These patients (i.e. negative patient characteristics) also presented
higher prevalence of tooth loss.

Tonetti ‘95 = Smoking
Retrospective
GTR with non-resorb membrane
- Two groups: Smokers (>10
cig/day) vs non-smokers
- Total 71 defects
-Smokers showed worse CAL gain at 1 year (2.1mm vs 5.2 mm)
- NSSD in bone filled

Trombelli ‘18 = smoking
Retrospective cohort study
-Regeneration therapy for intrabony
defect with bovine bone and EMD
-smokers vs non-smoker
-Total 22 defects in 6 mo study
- single flap approach
Non -smoker: smoker: PD reduction: 4.1vs. 5.3 mm, CAL gain:
3.5 vs. 4.5mm and recession was 0.5mm for both groups.
However, all were NSSD in both groups
- Smokers showed worse early wound healing
- Trend toward lower CAL gain and PD reduction in heavier smokers (11-20 cig/day vs 1-10 cig/day)
- minimally invasive approach with EMD and xenograft is a suitable treatment for intrabony defect in moderate smokers

Shirakata ‘14 = Diabetes
- Animal study (rats)
- 15 DM vs 15 non-DM rats
- GTR w/wo EMD
- NSSD of extent of new bone and CT between groups
- EMD has no influence on bone or cementum regeneration
- More adverse reactions in DM rats: worse wound healing and higher perspective recession

Mizytanu ‘20 = Diabetes
Prospective study
T2DM vs non-DM
- MIST or M-MIST with EMD but no
bone graft
- f/u for 3 Y
- HbA1c 6.82% avg in DM group

Minimally invasive surgery combined with EMD showed favorable outcomes in DM groups
- CAL gain was NSSD between well controlled vs poor controlled group (HbA1c 5.9% vs 7.2%)
At 3 years:
CAL gain:
* Diabetics: 3.8mm
* Healthy: 4.1mm
Bone fill:
* Diabetics: 58.3%
* Healthy: 65.5%
PD reduction:
* Diabetics: 4.5 mm
* Healthy: 4.7 mm

Question 20

What local factors affect GTR results?

Answer 20

Bowers ‘03
Bashutski ‘11
Interproximal bone height. Furcations with bony peaks above the furcation show higher percentage of complete closure.

Horizontal and vertical defects: If too large, has lower complete closure.
* ≥ 5mm -had lower frequency of complete clinical closure (53% vs 90% if horizontal defect < 4mm)

Root separation: Wide furcation entrance has a negative influence on clinical outcome.
* Only 61% of furcations presented complete closure if root divergence >4mm, compared to < 3mm (93%)

Depth: Shallow defects < 3mm reduce
wound stability (Laurell 1998)

# of residual walls: 3W>2W>1W. it is easier to maintained space and wound stability with greater # of walls

Angle of defect: Narrower, ≤25o between the tooth and defect, GTR is indicated. If the defect angles ≥ 37o, the outcome was not predictable. Overall, 1.6mm more attachment gain expected in narrow defect (Cortellini and Tonetti 2015).

Question 21

What did Bowers ‘03 find regarding furcation regenerations?

Answer 21

Horizontal probing of furcation associated with furcation closure: early lesions respond better than late lesions
* Complete closure: 53% of advanced (≥5 mm) lesions | 90% of early (≤4 mm) lesions
Morphological Measurements:
Root trunk length
* longer root trunks (5-6mm) > shorter root
trunks (4mm) (100% vs 71%)
Roof of Furcation to Base of Defect and
* Crest of Bone -> improved closure when smaller (ROF-BOD < 4mm)
(ROF-COB < 2mm)
Roof of Furcation - Proximal Bone Height - teeth with PBH at or above the ROF will have more complete closure compared to teeth with PBH below ROF (94% vs 70%)
Root Divergence at the Crest – narrower divergence is better
* (90% closure for <3mm vs 61% closure for >4mm)
The volume of the defect was not significantly correlated with
outcome
Outcome depends more on features than volume of defect
Healing Pattern and Appearance of New Tissue – tissue healing was scored as “typical, rapid, or delayed”.
Highest complete closure occurred in the rapid tissue healing category (89%).
Complete Tissue Coverage – sites that had complete tissue coverage had 80% complete closure while furcations with incomplete tissue coverage had 69% complete closure

Question 22

How does mobility affect GTR?

Answer 22

Schulz ‘00
To compare the regenerative outcome on splinting teeth with Natural coralline coral calcium (CCC)
- 70 defects and 3 groups: pre-splint vs post-splint vs non-splint. Splint was removed not earlier than 8 mo
- Results: pre-splinting teeth had significantly higher CAL gain, PD reduction and mobility reduction compared to non-splinting group after 48 wks (CAL gain: 5.4 vs 2.2mm, PD reduction: 5.1 vs 1.7mm).
- Might be due to loss of grafting material by tooth mobility

Trejo ‘04
- 64 pt treated with different regenerative procedures (GTR, EMD or combinational therapy)
- NSSD in PD, recession, and CAL gain with Miller’s Class 0, 1, and 2 mobility
-Conclusion: Slight mobility may not compromise the outcome of GTR

Cortellini ‘15
Tooth hypermobility is negatively associated with negative GTR outcome.
- Blood clot stability was influenced by tooth mobility. Splinting mobile teeth (Miller’s Class II and III is essential in the early healing phase.

Question 23

How does tissue thickness affect GTR?

Answer 23

Baldi ‘99
flap thickness >0.8 mm is required to achieve 100% root coverage in CAF root coverage procedure.

Hwang ‘06
> 1.1mm flap thickness is associated with success in CAF (to achieve complete root coverage)

Anderegg ‘95
37 class 1 or 2 facial furcation treated with GTR without bone graft or CAF
- Both thick and thin tissue groups had increase buccal recession after surgery
- Teeth with tissue < 1mm experience higher increase in buccal recession (2.1 vs 0.6 mm) at 6 mo

Question 24

What does Bashutski recommend for furcations with regards to vertical defect depth, horizontal defect depth, interrot separation?

Answer 24

Vertical defect depth:
* >4mm - consider non-GTR treatments (SRP, Odontoplasty, osteoplasty, tunneling, root resection, extraction
* If < 4mm - GTR

Horizontal defect depth:
* If >5mm: consider non-GTR treatments (SRP, Odontoplasty, osteoplasty, tunneling, root resection, extraction
* If < 5mm: GTR

Interroot separation:
* < 0.75 mm or >5mm: consider non-GTR treatments
* Between 0.75 to 5mm: GTR