Complete root coverage
77.9%
The percentage of studied Miller Class I–II sites reported with complete root coverage at long-term follow-up.
Published long-term evidence
PST® outcomes at a mean follow-up of 14.5 years.
This retrospective case series followed 28 patients and 68 Miller Class I–II recession sites for an average of 173.8 months.
28 patients68 recession sites173.8-month mean follow-upPeer-reviewed publication
Study summary
What the authors reported.
The figures below describe outcomes observed in this study population; they do not predict an individual patient’s result.
Mean root-defect coverage
86.6%
The average percentage of the original recession defect covered at the mean 14.5-year follow-up.
Patient esthetic satisfaction
95.1%
Patient-reported esthetic satisfaction across the recalled patients at long-term follow-up.
Evidence context: This was a retrospective case series, not a randomized trial. Results apply to the selected patients and sites studied and should be interpreted with the full paper, clinical examination, and professional judgment. Citation: Chao J, et al. Long-Term Retrospective Case Series of the Pinhole Surgical Technique. Int J Periodontics Restorative Dent 2026;46:299–305.
Clinical photographs
A documented case from the study.
Clinical photographs reproduced from the published case series—the same patient at baseline, 33 months, and the 18-year recall.
IJPRD series · 33 months and 18 years post-opView source ↗
Baseline
33 months
18 years
Read the source
Review the complete publication.
Use the PubMed record to confirm the study design, inclusion criteria, methods, outcomes, and limitations before citing the findings.
See clinical examples
Pair the paper with documented cases.
Review selected multi-year follow-ups, then open the Academy’s complete case gallery.
The complete evidence library
Every published Pinhole® study, in one place.
Peer-reviewed research on the Pinhole® Surgical Technique spanning 2012–2026—from the original study and the 14.5-year follow-up to the randomized trial and independent case series from around the world.
Peer-reviewed journalsRandomized controlled trial14.5-year follow-upIndependent case series
Start with the flagships
Three studies carry the core evidence.
The original feasibility study, the longest follow-up published to date, and the randomized head-to-head against the grafting gold standard.
The original · IJPRD 2012
81.2%
Complete root coverage in Class I–II sites, with 94.0% mean defect reduction, a 22.3-minute mean surgery time, and 95.1% patient satisfaction.
Longest follow-up · IJPRD 2025
86.6%
Mean root-defect coverage maintained at a mean 14.5 years across 68 Class I–II sites—with 77.9% complete coverage.
Randomized trial · Compendium 2025
Equivalent
Split-mouth trial in 36 patients: root coverage and recession reduction statistically equivalent to the connective-tissue graft—without the second surgical site.
By Dr. Chao and collaborators
The core research line.
Original research, the randomized trial, long-term follow-ups, and supporting protocols from the technique’s inventor and his co-investigators.
01
A Novel Approach to Root Coverage: The Pinhole® Surgical Technique
↗02Int J Periodontics & Restorative Dentistry · 2012 · Chao — the original study: 81.2% complete coverage in Class I–II sites, 94.0% mean defect reduction, 22.3-minute mean surgery time, 95.1% patient satisfaction.
Long-Term Retrospective Case Series of the Pinhole® Surgical Technique
↗03Int J Periodontics & Restorative Dentistry · 2025 · Chao, Reyes Rosales, El Chaar, Shibly, Al-Sabbagh, Ma — 28 patients, 68 Class I–II sites at a mean 14.5 years: 86.6% mean defect coverage, 77.9% complete coverage.
PST® + Collagen Membrane vs Coronally Advanced Flap + Connective Tissue Graft: A Split-Mouth Randomized Clinical Trial
↗04Compendium 46(1) · 2025 · Shibly, Chao, Albandar, Almehmadi, Al-Sabbagh — 36 patients, 1 year: root coverage 63.6% vs 65.4% and recession reduction 1.97 vs 1.98 mm, statistically equivalent.
Clinical Trial of PST® vs Connective Tissue Graft: Study Protocol
↗05University at Buffalo, Periodontics · 2020 · Shibly, Chao — the randomized, split-mouth, double-blinded protocol behind the trial: 52 subjects, endpoints through 24 months.
Treatment of 27 Class III Gingival Recession Sites: A 35-Month Case Study
↗06Journal of Cosmetic Dentistry · 2024 · Chao, Shibly, Tso, Ma — PST® combined with surgical crown shortening: complete coverage on maxillary teeth and near-complete on mandibular incisors.
PST® with Platelet-Rich Fibrin to Enhance Soft-Tissue Grafting
↗07Perio-Implant Advisory · 2025 · Froum, Chao — PRF as a natural scaffold: greater keratinized tissue width, better coverage, and reduced postoperative pain versus PST® alone.
The Chao Brushing Stent™: Protecting Gingival Surgical Sites During Oral Hygiene
↗08Journal of Clinical Dentistry and Oral Care 4(2) · 2026 · Chao, Mishail, Safa, Reyes Rosales — a custom-fit appliance that protects healing surgical sites while allowing brushing of exposed crowns.
Pinhole® Surgical Technique in Historical Perspective
↗Il Dentista Moderno · 2014 · Chao, Shanelec — the microsurgical origins of PST® and how it compares with free connective-tissue grafting.
Independent research
Studies and case series from around the world.
Investigations by unaffiliated clinicians and universities—including imaging studies, biomaterial comparisons, and multi-site case series.
09
PST® for Treatment of Marginal Tissue Recession
↗10J Indian Society of Periodontology 21(6) · 2017 · Reddy — independent case series of 18 sites: 96.7% mean root coverage with minimal complications.
Alveolar Bone Changes After Minimally Invasive Periodontal Surgery: A CBCT Evaluation
↗11Imaging Science in Dentistry 53(1) · 2023 · Shahmirzadi et al. — 3D CBCT imaging after PST® showed an average alveolar bone gain of more than 0.5 mm.
PST® With and Without A-PRF in Multiple Adjacent Recession Defects
↗12J Esthetic and Restorative Dentistry 36(2) · 2023 · Trivedi, Kolte, Kolte, Deshpande — randomized comparison across 165 sites; adding A-PRF improved depth, width, thickness, and esthetic scores.
PST® for Marginal Tissue Recession Coverage Using Amniotic Membrane
↗13Advances in Human Biology · 2024 · Patel et al. — significant 12-month improvement in recession depth, width, and attachment using an amniotic-membrane allograft.
PST® for Multiple Gingival Recession Defects: A Case Series
↗14Contemporary Clinical Dentistry 11(1) · 2020 · Agarwal et al. — 20 esthetic-zone sites with T-PRF membrane: 87% root coverage at six months with high patient satisfaction.
Re-invigoration of Pink Esthetics by a Novel Minimally Invasive Technique
↗15Contemporary Clinical Dentistry 10(4) · 2019 · Sharma, Dureja, Arora — two documented cases with complete root coverage and minimal discomfort.
Non-Invasive Pinhole® Technique With Propolis Application
↗16Int J Surgery Case Reports · 2021 · Mostafa, Mandil — propolis root conditioning alongside PST®: enhanced healing and minimal postoperative complications.
Collagen Membrane vs PRF Membrane With PST®
↗17Int J Scientific and Research Publications · 2021 · Choudhury et al. — both membranes achieved positive root coverage and gingival regeneration in Class I recession.
The Pinhole® Technique in the Treatment of Gingival Recession Defects
↗18Advances in Dentistry & Oral Health 13(1) · 2020 · Mostafa et al. — review of multiple-site treatment in a single appointment without donor sites or graft exposure.
Pinhole® Surgical Approach in Gingival Recession: A Case Report
↗19J Dental Sciences and Oral Rehabilitation · 2020 · Gaba et al. — documented case highlighting reduced discomfort and strong esthetic results.
Feasibilities of the Pinhole® Surgical Technique: Mini Review
↗Advances in Dentistry & Oral Health 4(3) · 2017 · Al-Almaie — review reporting up to 94% defect reduction with minimal postoperative complications.
Professional reviews and press
Perspectives from the wider profession.
Clinical reviews and professional coverage discussing where PST® fits in practice.
20
PST®: A Clinical Perspective and Treatment Considerations From a Periodontist
↗21Journal of the California Dental Association · Beck — in-depth professional review of benefits, limitations, patient selection, and long-term considerations.
PST®: A 10-Year Evaluation of Root Coverage
↗22Dental Economics · 2022 · Froum — decade-long evaluation reporting 81% complete root coverage in Class I–II defects.
Noninvasive Soft Tissue Advancement in Conjunction With Aesthetic Dentistry
↗23A Closer Look · 2018 · Zalesky — how PST® integrates with restorative and esthetic treatment planning.
Pinhole® Gum Surgery: Treatment for Gum Recession
↗Colgate · 2023 · medically reviewed consumer overview citing 96.7% root-coverage success and 95% esthetic satisfaction.
Findings above reflect each publication’s own study population and design; case reports and reviews carry different evidence weight than randomized trials. Read the full papers before citing.
For dentists
See how the evidence translates to training.
The free webinar covers the technique, case selection, and implementation—presented by Dr. Chao.