Single or repeated antimicrobial photodynamic therapy as adjunct to ultrasonic debridement in residual periodontal pockets: clinical, microbiological, and local biological effects.

This study aims to assess in residual periodontal pockets the clinical, microbiological, and local biological effects of antimicrobial photodynamic therapy (PDT), delivered after ultrasonic instrumentation either once or twice in a 1-week interval. A single center, three-arm randomized longitudinal study was carried out for 6 months. Twenty-eight systemically healthy patients on periodontal maintenance with residual pockets (pocket depth (PD) ≥5 mm, clinical attachment loss ≥2 mm, and bleeding upon probing (BOP+)) were included. Residual pockets on three teeth, separated from each other by at least two other teeth, served as study sites. After ultrasonic debridement, they were randomly assigned to either PDT delivered twice within 1 week (group A), PDT delivered only once (group B), or sham treatment without activating the laser (group C). Methylene blue was applied with a blunt irrigator tip into the pockets. Sites were irradiated with laser light at a wavelength of 670 nm using a light-diffusing tip introduced into the pocket. Initial PD was 5.9 ± 0.9, 6.3 ± 1.3, and 6.3 ± 1.5 mm in groups A, B, and C, respectively, differences being nonsignificant. PD was significantly reduced in all groups. At month 3, PD was significantly lower in groups A (2.9 ± 1.1 mm; p = 0.04) and B (2.8 ± 1.1 mm; p = 0.03) compared to group C (3.5 ± 1.2 mm). At month 6, none of the sites in group A had persisting pockets PD >4 mm and BOP+, whereas two sites in group B and four sites in group C stayed in this category. Detection frequencies of the studied microorganisms at >1,000 and >100.000 cells/ml did not change significantly from baseline to months 3 or 6 in any group. A significant overall decrease was observed from baseline to month 6 for C-reactive protein, serum amyloid A, fibrinogen, procalcitonin, and α-2 macroglobulin. When looking at the groups separately, C-reactive protein was significantly lower only if the laser had been activated twice (p < 0.05). Other differences between groups were not significant. A single or double episodes of PDT had some additional benefit over ultrasonic instrumentation alone.

Subgingival air-polishing with erythritol during periodontal maintenance: randomized clinical trial of twelve months.

OBJECTIVES: To evaluate repeated subgingival air-polishing in residual pockets with a new erythritol powder containing 0.3% chlorhexidine. MATERIAL AND METHODS: Single-centre, examiner masked, randomized clinical trial of 12 months with a two-arm, within-subject parallel design. Fifty patients in periodontal maintenance were monitored in 3-month intervals. At months 0, 3, 6 and 9, all sites presenting with a probing depth (PD) >4 mm were subject to subgingival air-polishing (test side) or ultrasonic debridement (control side). The primary endpoint was presence/absence of PD >4 mm after 12 months. RESULTS: Totally 6918 sites were monitored at baseline, 457 of them had a PD >4 mm (range 5-9 mm). The number of pockets >4 mm per subject, PD and bleeding on probing were significantly lower at month 12. Differences between test and control were not significant. There was a significant difference in favour of air-polishing for the perception of pain/discomfort. Differences of frequencies at >1000 and >100,000 cells/ml of six microorganisms between baseline and month 12 were not significant. At month 12, test sites were less frequently positive for Aggregatibacter actinomycetemcomitans at >1000 cells/ml than controls, and counts never exceeded 100,000 cells/ml. CONCLUSIONS: Repeated subgingival air-polishing reduced the number of pockets >4 mm similar to ultrasonic debridement. It was safe and induced less pain.