Dental Literature Watch · RCT · Oral surgery
PRF, PRGF and collagen on palatal wounds: no faster than leaving them alone
TL;DR
- PRF, PRGF and a collagen substitute did not speed up healing of standardised palatal wounds in healthy volunteers.
- At day 7, the point of greatest difference, mean open wound remaining was 35.7% for spontaneous healing, 38.8% for PRGF, 46.0% for collagen and 47.0% for PRF.
- Averaged across visits and sites, PRF (p = 0.018) and collagen (p = 0.042) left significantly larger open areas than spontaneous healing; PRGF did not differ significantly.
- Pain did not differ between treatments at any timepoint (p = 0.737), and fell significantly over time in all four arms.
- By day 14 residual open wound was 0.4-1.3% in every arm, with 85% of wounds fully closed.
- No adverse events were reported other than early suture loss at day 2 in four patients.
The study
| Element | Detail |
|---|---|
| Design | Within-subject randomised trial (DRKS00034761); single surgeon; outcome assessor blinded to the three dressing sites, but the control site was identifiable |
| Population | 20 systemically healthy volunteers, mean age 28.5 years, each with four standardised palatal wounds (6 mm punch, 3 mm deep) |
| Intervention | PRF, PRGF or collagen substitute (Geistlich Mucograft), each sutured with a criss-cross suture, against spontaneous healing (suture only) |
| Outcomes | Primary: remaining open wound area on photographs at days 2, 5, 7, 9, 12 and 14. Secondary: pain on a 0-10 numerical rating scale |
| Result: day 7 | Open wound remaining: control 35.7% · PRGF 38.8% · collagen 46.0% · PRF 47.0% |
| Result: pain | No significant difference between treatments (p = 0.737); PRGF versus control at day 7 p = 0.084. Anterior sites tended to be more painful than posterior sites |
| Funding | Osteology Foundation grant; material support from Geistlich Pharma and Dentavis; several authors report industry relationships |
💎 Insight — what this means chairside
A dressing is not automatically a help
In a clean, standardised wound in a healthy mouth, leaving the wound alone was at least as fast as any dressing.
The authors suggest any material on an open defect may act as a temporary barrier to epithelial migration.
In a clean, standardised wound in a healthy mouth, leaving the wound alone was at least as fast as any dressing.
The authors suggest any material on an open defect may act as a temporary barrier to epithelial migration.
Do not expect an analgesic benefit
Pain fell over time in every arm and no treatment separated from control.
Analgesic intake peaked on the day of surgery (mean 1.80 doses) and median consumption was zero from day 1.
Pain fell over time in every arm and no treatment separated from control.
Analgesic intake peaked on the day of surgery (mean 1.80 doses) and median consumption was zero from day 1.
Location matters more than you might think
Anterior defects tended to be more painful than posterior ones, yet they tended to heal faster.
The authors link this to thinner mucosa and higher vascularity in the anterior palate.
Anterior defects tended to be more painful than posterior ones, yet they tended to heal faster.
The authors link this to thinner mucosa and higher vascularity in the anterior palate.
⚠️ The catch
Why this sits at 2 of 5
It is a small experimental model, not a clinical-surgery trial.
The conclusions are confirmatory of recent RCTs that also found no clear benefit of PRF.
It is a small experimental model, not a clinical-surgery trial.
The conclusions are confirmatory of recent RCTs that also found no clear benefit of PRF.
Twenty people, a 14-day window
Twenty healthy, mostly young volunteers (mean age 28.5) with experimental wounds are a low-morbidity, high-healing model.
The authors say the findings may not transfer to larger defects or to smokers, people with diabetes or others with impaired healing.
Twenty healthy, mostly young volunteers (mean age 28.5) with experimental wounds are a low-morbidity, high-healing model.
The authors say the findings may not transfer to larger defects or to smokers, people with diabetes or others with impaired healing.
Experimental 6 × 3 mm defects, not real graft donor sites
Four wounds sat close together in one palate, so growth-factor diffusion between sites cannot be excluded.
Analgesic use was not standardised, and the control site could not be blinded.
Four wounds sat close together in one palate, so growth-factor diffusion between sites cannot be excluded.
Analgesic use was not standardised, and the control site could not be blinded.
Heavy industry ties
Funding included a grant from the Osteology Foundation and material support from Geistlich Pharma, whose product was a comparator.
Several authors report grants, consultancy or personal fees from Geistlich, Straumann and others; the result went against the commercial grain, which is reassuring but still worth knowing.
Funding included a grant from the Osteology Foundation and material support from Geistlich Pharma, whose product was a comparator.
Several authors report grants, consultancy or personal fees from Geistlich, Straumann and others; the result went against the commercial grain, which is reassuring but still worth knowing.
⚡ Bottom line
- Healthy patient, small clean palatal wound → a PRF, PRGF or collagen dressing is not shown to speed healing or cut pain; leaving it alone is reasonable.
- Smoker, diabetic or poor healer → this trial does not answer the question, because none of those patients were the model.
- Large graft donor site → a 6 mm wound is not the same; the authors call for studies in larger wounds.
- Patient asks if the platelet product will hurt less → in this trial, no difference in pain was found.
🧪 Questions
Tap an answer — instant grade, deciding line, and the trap.
In a randomised trial of standardised palatal wounds in 20 healthy volunteers, which arm had the least open wound remaining at day 7?
Spontaneous healing had 35.7% of the wound still open at day 7, the lowest of the four arms. PRGF was the closest at 38.8% and did not differ significantly from control. Collagen left 46.0% and PRF 47.0% open, and across all visits both were significantly slower than control (p = 0.042 and p = 0.018). Trap: PRGF, the growth-factor arm that sounds like it should win.
A patient asks whether a platelet-rich dressing would hurt less on a standardised palatal wound. Which statement is supported by this trial?
There were no significant differences in pain between treatments at any timepoint (p = 0.737), and scores fell significantly over time in every arm. PRGF versus control at day 7 had p = 0.084 with a large effect size, which is not significant: this is the trap. Collagen showed no pain advantage, and the shielding mechanism is not demonstrated. Analgesic consumption was reported overall and was not standardised, so no arm-by-arm reduction is claimed.