Transgingival photodynamic therapy (tg-aPDT) adjunctive to subgingival mechanical instrumentation in supportive periodontal therapy. A randomized controlled clinical study

A novel investigational preclinical model to assess fluence rate for dental oral craniofacial tissues

OBJECTIVE

Photodynamic Therapy (PDT) and Photobiomodulation (PBM) are recognized for their potential in treating head and neck conditions. The heterogeneity of human tissue optical properties presents a challenge for effective dosimetry. The porcine mandible cadaver serves as an excellent model and has several similarities to human tissues of the dental oral craniofacial complex. This study aims to validate a novel modeling system that will help refine PDT and PBM dosimetry for the head and neck region.

METHODS AND MATERIALS

Light transmission was analyzed through several tissue combinations at distances of 2 mm to 10 mm. Maximum light fluence rates (mW/cm2) were compared across tissue types to reveal the effects of tissue heterogeneity.

RESULTS

The study revealed that light fluence is affected by tissue composition, with dentin/enamel showing reduced transmission and soft tissue regions exhibiting elevated values. The porcine model has proven to be efficient in mimicking human tissue responses to light, enabling the potential to optimize future protocols.

CONCLUSION

The porcine mandible cadaver is a novel model to understand the complex interactions between light and tissue. This study provides a foundation for future investigations into dosimetry optimization for PDT and PBM.

Photodynamic therapy in periodontitis: A narrative review

BACKGROUND

Periodontitis, a chronic infectious disease, is primarily caused by a dysbiotic microbiome, leading to the destruction of tooth-supporting tissues and tooth loss. Photodynamic therapy (PDT), which combines excitation light with photosensitizers (PS) and oxygen to produce antibacterial reactive oxygen species, is emerging as a promising adjuvant treatment for periodontitis.

METHODS

This review focuses on studies examining the antibacterial effects of PDT against periodontal pathogens. It also explores the impact of PDT on various aspects of periodontal health, including periodontal immune cells, human gingival fibroblasts, gingival collagen, inflammatory mediators, cytokines in the periodontium, vascular oxidative stress, vascular behavior, and alveolar bone health. Clinical trials assessing the types of PSs and light sources used in PDT, as well as its effects on clinical and immune factors in gingival sulcus fluid and the bacterial composition of dental plaque, are discussed.

RESULTS

The findings indicate that PDT is effective in reducing periodontal pathogens and improving markers of periodontal health. It has shown positive impacts on periodontal immune response, tissue integrity, and alveolar bone preservation. Clinical trials have demonstrated improvements in periodontal health and alterations in the microbial composition of dental plaque when PDT is used alongside conventional treatments.

CONCLUSIONS

PDT offers a promising adjunctive treatment for periodontitis, with benefits in bacterial reduction, tissue healing, and immune modulation. This article highlights the potential of PDT in periodontal therapy and emphasizes the need for further research to refine its clinical application and efficacy.

Application of Different Wavelengths of LED Lights in Antimicrobial Photodynamic Therapy for the Treatment of Periodontal Disease

Therapeutic light has been increasingly used in clinical dentistry for surgical ablation, disinfection, bio-stimulation, reduction in inflammation, and promotion of wound healing. Photodynamic therapy (PDT), a type of phototherapy, has been used to selectively destroy tumor cells. Antimicrobial PDT (a-PDT) is used to inactivate causative bacteria in infectious oral diseases, such as periodontitis. Several studies have reported that this minimally invasive technique has favorable therapeutic outcomes with a low probability of adverse effects. PDT is based on the photochemical reaction between light, a photosensitizer, and oxygen, which affects its efficacy. Low-power lasers have been predominantly used in phototherapy for periodontal treatments, while light-emitting diodes (LEDs) have received considerable attention as a novel light source in recent years. LEDs can emit broad wavelengths of light, from infrared to ultraviolet, and the lower directivity of LED light appears to be suitable for plaque control over large and complex surfaces. In addition, LED devices are small, lightweight, and less expensive than lasers. Although limited evidence exists on LED-based a-PDT for periodontitis, a-PDT using red or blue LED light could be effective in attenuating bacteria associated with periodontal diseases. LEDs have the potential to provide a new direction for light therapy in periodontics.

Suppression of subgingival bacteria by antimicrobial photodynamic therapy using transgingival irradiation: A randomized clinical trial

BACKGROUND

Antimicrobial photodynamic therapy (aPDT) is an effective method for eradicating bacteria in periodontal therapy. Standard aPDT requires the insertion of a laser tip into a periodontal pocket, in which the direction of irradiation is limited. Therefore, we devised an aPDT method that uses a transgingival near-infrared wavelength and indocyanine green-encapsulated and chitosan-coated nanoparticles as a photosensitizer.

METHODS

Forty patients undergoing supportive periodontal therapy, who had a single root tooth with a pocket of 5 mm or deeper, were used as subjects. In the test group, aPDT was performed by laser irradiation from outside the gingiva using photosensitizer nanoparticles. In the control group, pseudo aPDT without photosensitizer was performed by transgingival irradiation. Subgingival plaque was sampled from inside the pocket before, immediately after, and 1 week after treatment, and evaluated by colony counting and real-time polymerase chain reaction.

RESULTS

There were no significant differences in age, sex, periodontal pocket depth, and bleeding on probing between the test and control groups. Compared with the colony count before treatment, the count in the test group was significantly reduced immediately after treatment. The number of patients with colony reduction to ≤50% and ≤10% was significantly higher in the test group than in the control group. None of the participants reported pain, although one participant reported discomfort.

CONCLUSION

As a bacterial control method for residual pockets in patients undergoing supportive periodontal therapy, transgingival aPDT is a promising treatment strategy that is not generally accompanied by pain or discomfort.

Laser treatments as an adjunct to non-surgical periodontal therapy in subjects with periodontitis and type 2 diabetes mellitus: a systematic review and meta-analysis

OBJECTIVES

Periodontal disease and diabetes have an extensively investigated bidirectional correlation. Non-surgical periodontal treatment (NSPT) was proven to contribute to glycemic control. Moreover, it may benefit from the association of adjunctive therapies. The aim of the present systematic review is to assess the clinical efficacy of NSPT in association with laser (LT) or photodynamic therapy (PDT) in controlled or uncontrolled diabetic patients, and to grade the level of evidence.

MATERIALS AND METHODS

Randomized controlled clinical trials with at least 3-month follow-up were searched in MEDLINE via OVID, EMBASE, and Cochrane Central, screened for inclusion, and grouped based on the performed treatments, follow-up time, type of diabetes, and level of glycemic control.

RESULTS

Eleven RCTs with 504 total subjects were included. The adjunct of PDT showed a statistically significant 6-month difference in PD changes (with low certainty of evidence), but not in CAL changes, while a significant difference in 3-month PD and CAL changes was found with the adjunct of LT (low certainty of evidence). Patients treated with PDT registered a higher decrease in HbA1c levels at 3 months, but no significant difference was noted at 6 months; LT also led to better HbA1c changes at 3 months with a moderate certainty of evidence.

CONCLUSION

Despite the promising short-term HbA1c decrease, the results should be interpreted with caution due to the small effect sizes and the statistical heterogeneity, and further evidence from well-designed RCTs is needed to support the routine use of PDT or LT in adjunct to NSPT.

Home-Applied Dual-Light Photodynamic Therapy in the Treatment of Stable Chronic Periodontitis (HOPE-CP)-Three-Month Interim Results

A single-site, randomized clinical trial was designed to determine the efficacy of regular home use of Lumoral® dual-light antibacterial aPDT in periodontitis patients. For the study, 200 patients were randomized to receive non-surgical periodontal treatment (NSPT), including standardized hygiene instructions and electric toothbrush, scaling and root planing, or NSPT with adjunctive Lumoral® treatment. A complete clinical intraoral examination was conducted in the beginning, at three months, and at six months. This report presents the three-month results of the first 59 consecutive randomized subjects. At three months, bleeding on probing (BOP) was lower in the NSPT + Lumoral®-group than in the NSPT group (p = 0.045), and more patients in the NSPT + Lumoral®-group had their BOP below 10% (54% vs. 22%, respectively, p = 0.008). In addition, patients in the NSPT + Lumoral®-group improved their oral hygiene by visible-plaque-index (p = 0.0003), while the NSPT group showed no statistical improvement compared to the baseline. Both groups significantly reduced the number of deep periodontal pockets, but more patients with a reduction in their deep pocket number were found in the NSPT + Lumoral® group (92% vs. 63%, p = 0.02). Patients whose number of deep pockets was reduced by 50% or more were also more frequent in the NSPT + Lumoral®-group (71% vs. 33%, p = 0.01). Patients with initially less than ten deep pockets had fewer deep pockets at the three-month follow-up in the Lumoral® group (p = 0.01). In conclusion, adjunctive use of Lumoral® in NSPT results in improved treatment outcomes at three months post-therapy.

The efficacy of adjunctive periodontal therapies during supportive periodontal care in patients with residual pockets. A systematic review and meta-analysis

While it is well-established that patients that develop signs of relapsing periodontitis in supportive periodontal care (SPC) will need to repeat subgingival instrumentation of the residual pockets, less certainty is available in terms of which protocol should be followed and whether the use of adjunctive therapies or physical agents might provide additional benefits to repeated instrumentation alone. The aim of this systematic review was therefore to assess whether repeating subgingival instrumentation in combination with adjunctive therapies (other than antimicrobials) might provide a significant benefit in terms of pocket closure, probing pocket depth (PPD) reduction or clinical attachment level (CAL) gain in patients during SPC with residual/relapsing pockets. Four databases were searched to identify randomized controlled trials (RCTs) and controlled clinical trials (CCTs) with a minimum follow-up of 3 months that investigated the use of adjunctive therapies (other than antimicrobials) in case of residual/relapsing pockets in patients in SPC since at least 3 months. Data extraction and risk of bias assessment were performed in the studies meeting the inclusion criteria and meta-analysis was performed when ≥3 studies assessing the same adjunctive therapy were identified. 12 studies (2 CCTs and 10 RCTs) were included for qualitative analysis. Meta-analysis was performed only for 3 studies on the adjunctive use of photodynamic therapy (PDT) and it indicated a nonsignificant benefit compared to the placebo in terms of PPD reduction and CAL gain at 3 months (weighted mean difference 0.07 and -0.03, respectively) and at 6 months of follow-up (weighted mean difference -0.09 and -0.18, respectively). While antiseptics did not provide significant benefits, one study on probiotics and one on the use of vitamin D and calcium supplementation showed significant improvements in periodontal parameters. There is currently insufficient/poor evidence to determine the efficacy of adjunctive strategies (other than antimicrobials) to improve the outcomes of SPC in case of residual/relapsing pockets.