The adjunctive effect of photodynamic therapy for residual pockets in single-rooted teeth: a randomized controlled clinical trial

Antimicrobial photodynamic effect to treat residual pockets in periodontal patients: a randomized controlled clinical trial

AIM

A randomized controlled clinical trial was designed to evaluate the efficacy of the photodynamic therapy (PDT) in the treatment of residual pockets of chronic periodontitis patients.

MATERIAL AND METHODS

Thirty-four patients with at least four residual periodontal pockets undergoing maintenance care were included and randomly assigned to test group (PDT, n = 18) or control group (sham procedure, n = 16). The intervention was performed at baseline, 3, 6 and 12 months. Clinical parameters such as pocket probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP) and plaque index (PI) were measured before intervention and after 3, 6 and 12 months. Subgingival samples were obtained at baseline, and after 7 days, 3, 6 and 12 months to quantify Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia by real-time polimerase chain reaction (PCR).

RESULTS

All clinical variables showed significant improvement during the study, but there was no significant difference between test and control groups. The microbiological analyses showed no differences between groups at any time during the study.

CONCLUSION

Within the limits of this clinical trial and considering the laser and photosensitizer protocol used, PDT failed to demonstrate additional clinical and bacteriological benefits in residual pockets treatment.

Real-time evaluation of two light delivery systems for photodynamic disinfection of Candida albicans biofilm in curved root canals

Antimicrobial photodynamic therapy (APDT) combined with endodontic treatment has been recognized as an alternative approach to complement conventional root canal disinfection methods on bacterial biofilms. We developed an in  vitro model of bioluminescent Candida albicans biofilm inside curved dental root canals and investigated the microbial reduction produced when different light delivery methods are employed. Each light delivery method was evaluated in respect to the light distribution provided inside curved root canals. After conventional endodontic preparation, teeth were sterilized before canals were contaminated by a bioluminescent strain of C. albicans (CEC789). Methylene blue (90 μM) was introduced into the canals and then irradiated (λ = 660 nm, P = 100 mW, beam diameter = 2 mm) with laser tip either in contact with pulp chamber or within the canal using an optical diffuser fiber. Light distribution was evaluated by CCD camera, and microbial reduction was monitored through bioluminescence imaging. Our findings demonstrated that the bioluminescent C. albicans biofilm model had good reproducibility and uniformity. Light distribution in dental tissue was markedly dependent on the light delivery system, and this strategy was directly related to microbial destruction. Both light delivery systems performed significant fungal inactivation. However, when irradiation was performed with optical diffuser fiber, microbial burden reduction was nearly 100 times more effective. Bioluminescence is an interesting real-time analysis to endodontic C. albicans biofilm inactivation. APDT showed to be an effective way to inactivate C. albicans biofilms. Diffuser fibers provided optimized light distribution inside curved root canals and significantly increased APDT efficiency.

Adjunctive photodynamic therapy to non-surgical treatment of chronic periodontitis: a systematic review and meta-analysis

AIM

To investigate the efficacy of antimicrobial photodynamic therapy (aPDT) adjunctive to scaling root planing (SRP) in patients with chronic periodontitis.

METHODS

A meta-analysis was conducted according to the PRISMA statement and Cochrane Collaboration recommendations. Two independent reviewers performed an extensive literature search and manual search on seven databases. Mean differences (MD) and 95% confidence intervals (CI) were calculated for clinical attachment level (CAL) gain and probing depth (PD) reduction. The I(2) test was used for inter-study heterogeneity. Publication bias was examined by Egger's regression test and the trim-and-fill method.

RESULTS

Sensitivity analysis of 14 randomized clinical trials (RCTs) revealed differences in PD reduction (MD 0.19, 95% CI 0.07-0.31, p = 0.002) and CAL gain (MD 0.37, 95% CI 0.26-0.47, p < 0.0001) in favour of SRP + aPDT, with no evidence of heterogeneity. Subgroup analysis revealed the absence of heterogeneity in RCTs, with high risk of bias for PD reduction and CAL gain. No evidence of publication bias was detected.

CONCLUSIONS

The use of adjunctive aPDT to conventional SRP provides short-term benefits. The evidence to support its clinical medium/long-term efficacy is insufficient. Further high-quality RCTs are needed to investigate the influence of potential confounders on the efficacy of adjunctive aPDT.

The sensitivity in the IR spectrum of the intact and pathological tissues by laser biophotometry

In this paper, we use the laser biophotometry for in vivo investigations, searching the most sensitive interactions of the near-infrared spectrum with different tissues. The experimental methods are based on the average reflection coefficient (ARC) measurements. For healthy persons, ARC is the average of five values provided by the biophotometer. The probe is applied on dry skin with minimum pilosity, in five regions: left-right shank, left-right forearm, and epigastrium. For the pathological tissues, the emitting terminal is moved over the suspected area, controlling the reflection coefficient level, till a minimum value occurs, as ARC-Pathological. Then, the probe is moved on the symmetrical healthy region of the body to read the complementary coefficient from intact tissue, ARC-Intact, from the same patient. The experimental results show an ARC range between 67 and 59 mW for intact tissues and a lower range, up to 58-42 mW, for pathological tissues. The method is efficient only in those pathological processes accompanied by variable skin depigmentation, water retention, inflammation, thrombosis, or swelling. Frequently, the ARC ranges are overlapping for some diseases. This induces uncertain diagnosis. Therefore, a statistical algorithm is adopted for a differential diagnosis. The laser biophotometry provides a quantitative biometric parameter, ARC, suitable for fast diagnosis in the internal and emergency medicine. These laser biophotometry measurements are representatives for the Romanian clinical trials.

Effect of low-level laser therapy on odontoblast-like cells exposed to bleaching agent

The aim of the present study was to evaluate the effect of low-level laser therapy (LLLT) on odontoblast-like MDPC-23 cells exposed to carbamide peroxide (CP 0.01%-2.21 μg/mL of H2O2). The cells were seeded in sterile 24-well plates for 72 h. Eight groups were established according to the exposure or not to the bleaching agents and the laser energy doses tested (0, 4, 10, and 15 J/cm(2)). After exposing the cells to 0.01% CP for 1 h, this bleaching solution was replaced by fresh culture medium. The cells were then irradiated (three sections) with a near-infrared diode laser (InGaAsP-780 ± 3 nm, 40 mW), with intervals of 24 h. The 0.01% CP solution caused statistically significant reductions in cell metabolism and alkaline phosphate (ALP) activity when compared with those of the groups not exposed to the bleaching agent. The LLLT did not modulate cell metabolism; however, the dose of 4 J/cm(2) increased the ALP activity. It was concluded that 0.01% CP reduces the MDPC-23 cell metabolism and ALP activity. The LLLT in the parameters tested did not influence the cell metabolism of the cultured cells; nevertheless, the laser dose of 4 J/cm(2) increases the ALP activity in groups both with and without exposure to the bleaching agent.

Additional effects of aPDT on nonsurgical periodontal treatment with doxycycline in type II diabetes: a randomized, controlled clinical trial

The association of doxycycline and periodontal treatment in non-controlled diabetes mellitus (DM) has shown positive results on clinical and metabolic parameters. Antimicrobial photodynamic therapy (aPDT) is a local and painless antimicrobial treatment that can be applied in periodontal treatment without systemic risks. The aim of this study was to evaluate the potential improvement of aPDT on clinical and metabolic effects in patients with type 2 diabetes mellitus in conjunction with nonsurgical periodontal treatment plus doxycycline. Thirty patients with type 2 diabetes and diagnosis of chronic periodontitis were treated with scaling and root planning (SRP; N = 15) or SRP plus phenothiazine chloride photosensitizer-induced aPDT (SRP + aPDT, N = 15). Patients of both groups took doxycycline (100 mg/day) for 2 weeks and plaque index, bleeding on probe (BOP), probing pocket depth (PPD), suppuration, clinical attachment level (CAL), and glycated hemoglobin levels (HbA1c) were measured at baseline and 3 months after therapy. An improvement in clinical parameters such as PPD, CAL, S, and BOP between groups was observed but without statistical significance (p > 0.05). Intragroup analysis showed a significant reduction of HbA1c (8.5 ± 0.9 to 7.5 ± 0.1, p < 0.01) in the SRP + aPDT group. The differences of HbA1c between baseline and 3 months were greater for the SRP + aPDT (11.4 %) than SRP (10 %) (0.87 ± 0.9 and 0.4 ± 0.84 respectively; p < 0.05). A single application of the aPDT as an adjunct to periodontal treatment did not show additional benefits in the clinical parameters but resulted in a slight greater decrease in HbA1c.

Esthetic treatment of gingival hyperpigmentation with Nd:YAG laser or scalpel technique: a 6-month RCT of patient and professional assessment

This double-masked, randomized controlled trial with a split-mouth design aimed to compare patient- and professional-centered outcomes using different therapeutic approaches-neodymium-yttrium aluminum garnet (Nd:YAG) laser or scalpel technique-for gingival depigmentation. Patients presenting bilateral melanin gingival hyperpigmentation and who requested cosmetic therapy were recruited. Contralateral quadrants were randomly assigned to receive Nd:YAG laser (settings: 6 W, 60 mJ/pulse, and 100 Hz) or scalpel technique. Patient morbidity experienced at intratherapy and during the first postoperative week was evaluated. In addition, after 6 months, the cosmetic results achieved for the different therapeutic approaches were evaluated by patients and professionals. The chair time of each technique was also calculated. Patient-oriented outcomes concerning intratherapy morbidity did not demonstrate any differences between groups (p > 0.05), although a higher extent of discomfort/pain was experienced in the side treated by the scalpel technique compared to the Nd:YAG laser procedure during the first posttherapy week (p < 0.05). Regarding to cosmetic outcomes, no differences between techniques were observed for patient and professionals (p > 0.05). Significantly higher chair time was required for the scalpel technique than for the Nd:YAG laser therapy (p < 0.05). The Nd:YAG laser or the scalpel technique may be successfully used for the treatment of melanin gingival hyperpigmentation. However, the use of the Nd:YAG laser has presented advantages in terms of less discomfort/pain during the posttherapy period and a reduction of treatment chair time.