Recession reduction
1.97 vs 1.98 mm
PST® + collagen membrane vs CAF + connective-tissue graft—statistically equivalent (P = .53).
Randomized head-to-head evidence
Same results as the gold standard—without the second surgery.
A split-mouth randomized clinical trial treated 36 patients with both techniques in the same mouth—PST® with a collagen membrane on one side, coronally advanced flap with connective-tissue graft on the other—and compared them at one year.
36 patientsRandomized split-mouth designBoth techniques, same mouth1-year follow-up
What the trial measured
No significant difference in efficacy.
The figures below describe outcomes in this trial population; they do not predict an individual patient’s result.
Mean root coverage
63.6% vs 65.4%
Statistically equivalent between the two techniques at one year (P = .72).
Attachment gain
Both sides
Both treatments produced a significant gain in clinical attachment level, with no difference between them (P = .9).
One measure favored the graft: keratinized tissue width increased significantly in the graft group over the year (2.38 → 2.61 mm, P = .002). Patient-reported outcomes, including postoperative pain and satisfaction, showed no significant difference. Citation: Shibly O, Chao JC, Albandar JM, Almehmadi N, Al-Sabbagh M. Compendium 2025;46(1)—split-mouth randomized clinical trial.
Two techniques, one mouth
What each side of the mouth received.
The split-mouth design means every patient served as their own control—the strongest way to compare two surgical techniques.
| Compared point | PST® + collagen membrane | CAF + connective tissue graft |
|---|---|---|
| Surgical sites | One | Two, including the palate |
| Donor tissue | None | Harvested from the palate |
| Closure | No sutures | Sutured + removal visit |
| Recession reduction | 1.97 mm | 1.98 mm |
| Mean root coverage | 63.6% | 65.4% |
Case photographs from the trial
Both sides, baseline and one year.
Representative cases as published—the control side treated with the graft, and the contralateral side treated with PST®.
Control · CAF + connective-tissue graftRead the study ↗
Baseline · Fig 1
1 year · Fig 2
Test · PST® + collagen matrixRead the study ↗
Baseline · Fig 3
1 year · Fig 4
Method: split-mouth randomized trial—coronally advanced flap with connective-tissue graft on one side, PST® with a collagen matrix on the contralateral side; both assessed at one year. Representative photographs, figure numbering as published.
Read the source
Review the complete publication.
Use the full text to confirm the trial design, inclusion criteria, methods, outcomes, and limitations before citing the findings.
For dentists
See how the evidence translates to training.
The free webinar covers the technique, case selection, and implementation—presented by Dr. Chao.