Efficacy of the Entire Papilla Preservation Technique With and Without the Use of L-PRF as a Regenerative Material for the Treatment of Infrabony Defects: A Randomized Controlled Clinical Trial

Periodontitis is an infectious disease of bacterial origin that leads to a slow and progressive loss of periodontal attachment, resulting in the destruction of supporting tissues and the formation of periodontal pockets. These pockets can be classified as suprabony or intrabony, with the latter being those where the bottom of the pocket is apical to the level of the adjacent alveolar bone and the bone loss presents a vertical pattern. Intraosseous defects affect 36% of periodontal patients and are particularly challenging to treat due to their association with greater loss of periodontal support, increased clinical attachment loss, deeper probing depths, greater tooth mobility, and functional consequences for the patient; thus, they have a less favorable prognosis and response to non-surgical periodontal treatment.

Lang et al. established that periodontal defects can be successfully treated with non-surgical therapy, limiting additional surgical interventions to sites with an initial probing depth of 6 mm or more, or to advanced periodontal lesions that, after a successful etiological phase, still retain residual pockets ≥ 6 mm. Given this, surgical periodontal therapy becomes a therapeutic alternative for intraosseous defects associated with advanced periodontal destruction, aiming to reduce tooth loss over time, recover lost periodontal support, and improve patient's quality of life.

Different surgical alternatives have been developed to enhance short- and long-term clinical outcomes in teeth with infrabony defects and reduced periodontal support. If the contour of the existing bone and the number of remaining bony walls are favorable, regenerative surgical therapy could successfully regenerate bone up to the level of the alveolar crest. The use of materials such as a demineralized allogeneic bone matrix in guided tissue regeneration has shown to achieve reductions in probing depths, gains in clinical attachment level, and filling of treated defects compared to defect instrumentation through open flap debridement.

However, these treatment modalities are sensitive to technique, and their outcomes depend on various factors including patient-dependent factors such as plaque control and smoking habits; site-specific factors, such as defect morphology; and factors inherent to the surgical techniques employed. Consequently, the failure of conventional surgical techniques, such as early exposure of the regenerated area, has been reported in the scientific literature and is even more frequent with the use of membranes and bone substitutes.

In light of this, innovations in flap design and soft tissue management have reduced failures associated with early wound closure. Surgical techniques such as simplified papilla flap and modified techniques, minimally invasive surgical technique (MIST), and modified minimally invasive surgical technique (M-MIST) have been designed to protect the regeneration site and facilitate the stability of the blood clot.