A novel sub-junctional pinhole technique (S-PHT) in treating intrabony defects of stage III periodontitis – Case Series

The health of the gums and the bone that holds our teeth in place depends on a delicate, living seal. This seal is formed by a thin layer of tissue called the junctional epithelium, which clings tightly to the tooth surface just below the gumline. Its job is to act as a barrier, keeping the bacteria found in dental plaque from invading the deeper tissues and bone. When this seal is broken or damaged, bacteria can slip underneath, causing the bone to dissolve and creating deep pockets around the tooth. This condition, known as periodontitis, is a leading cause of tooth loss. For decades, the standard way to fix these deep pockets involved lifting the gums up like a curtain to clean the area and place bone graft material inside. While effective, this method often damages the very seal needed to protect the healing site, leading to sensitivity, discomfort, and sometimes a loss of the gum tissue that supports the tooth.

A new approach described in a recent study from Egypt offers a different path, one that avoids lifting the gums entirely. Researchers tested a technique called the sub-junctional pinhole technique, or S-PHT, on ten patients with moderate to severe periodontitis. Instead of making large incisions, the team created a tiny opening, just a few millimeters wide, on the cheek side of the gum, positioned carefully below the protective seal but above the bone defect. Through this microscopic doorway, they cleaned out the infected tissue and injected bone-grafting material directly into the hole in the bone. The goal was to let the natural, intact seal of the gum remain undisturbed, acting as a biological cover that protects the new material while the body heals. The study, which followed patients for nine months, suggests that this minimally invasive method can successfully fill bone defects and reduce gum pockets without the trauma of traditional surgery, offering a gentler option for patients struggling with gum disease.

The study focused on ten non-smoking adults, ranging in age from 39 to 61, who had deep pockets around their teeth caused by bone loss. Before the specific procedure began, all patients underwent a thorough cleaning to remove plaque and tartar from above and below the gumline. Four weeks later, once the gums had settled, the researchers performed the pinhole procedure. Using specialized tools and magnification, they made a small entry point on the facial surface of the gum, opposite the area where the bone was missing. Through this tiny hole, they carefully removed the inflamed tissue that had accumulated in the bone defect and then packed the space with a xenogenic graft material, which is bone derived from a cow and processed to be safe for human use. The graft was pushed in until the defect was completely filled, a process confirmed by taking X-rays and three-dimensional scans during the surgery. If the tiny hole was slightly larger than a millimeter, a single stitch was used to close it; otherwise, it was left to heal on its own.

The results after nine months were encouraging. Every single site treated showed a reduction in the depth of the gum pocket, with all measurements dropping to four millimeters or less, a level generally considered healthy. In six out of the ten cases, the gum tissue had grown back enough to gain at least three millimeters of attachment to the tooth, a significant sign of regeneration. Furthermore, six of the ten sites met a strict set of success criteria: the pocket was shallow, the gum had reattached firmly, and there was no bleeding when the area was gently probed. Perhaps most notably, the bone defects themselves showed substantial filling. On average, the missing bone was filled by 3.1 millimeters, a statistically significant improvement that indicates the graft material stayed in place and supported new bone growth. The patients reported very little pain, with discomfort levels dropping to near zero within three days of the procedure, and no serious complications like infection or exposed graft material were observed.

What makes this finding particularly interesting is how the technique manages to heal the bone without disturbing the soft tissue architecture. Traditional surgery often requires lifting the gum flap, which can compromise the blood supply and the stability of the clot that forms the foundation for healing. By keeping the gum tissue intact and only creating a pinhole access, the researchers preserved the natural blood flow and the protective seal of the junctional epithelium. This approach seems to create a stable environment where the graft material can do its work without being disturbed by the movement of the gum tissue. The study also noted that the procedure took between 15 and 30 minutes per tooth, suggesting it is a practical option for clinical use. While the sample size was small and the follow-up period of nine months is relatively short, the data indicates that this method is a viable, patient-friendly alternative that achieves strong clinical outcomes with minimal discomfort.

The researchers acknowledge that while these early results are promising, larger studies with longer follow-up periods are needed to confirm that the bone regeneration is permanent and to see how the technique compares to other minimally invasive surgical methods. They also suggest that future work could explore using specialized instruments, such as a perioscope, to visualize the defect through the pinhole more clearly, ensuring the graft is placed perfectly. For now, the study provides a compelling demonstration that it is possible to treat deep bone defects in the jaw by working through a tiny opening, leaving the body's natural defenses intact to guide the healing process. This shift toward less invasive techniques represents a quiet but significant step forward in periodontal care, prioritizing the preservation of healthy tissue to achieve better long-term results for patients.