hard and smooth. Local anesthesia was used as necessary for
patient comfort. In the SRP+PB and SRP+AP groups, the
periodontal pockets were gently irrigated with 2 ml of 0.9%
sterile saline in a syringe fitted with a 21-gauge blunted needle
after SRP. Then, the PB or AP gels were gently applied
subgingivally into the periodontal pockets around the selected
teeth (Figure 2). A sufficient amount of gel was administered to
fill each periodontal pocket to the gingival margin. The excess
was removed using sterile cotton pellets. Strict guidance was
provided to the patients not to rinse, drink, or eat for 1 hour after
the gel was applied. This gel application was repeated 1, 2, and 3
weeks following the baseline. All clinical parameters and
radiographic examinations were re-examined at 3 and 6 months
after 1 week of gel administration. The AP or PB gels were also
re-administered at the 3-month re-examination. An examiner