Lethal photosensitization of bacteria in subgingival plaque from patients with chronic periodontitis

Bactericidal Effect of Different Photochemical-Based Therapy Options on Implant Surfaces-An In Vitro Study

Objectives: Photochemical systems are frequently recommended as an adjuvant treatment option in peri-implantitis therapy. The aim of the present study was to evaluate the efficacy of these treatment options, as well as a novel curcumin-based option, in a biofilm model on implants. Methods: Eighty dental implants were inoculated with an artificial biofilm of periodontal pathogens and placed in peri-implant pocket models. The following groups were analyzed: I, photodynamic therapy (PDT); II, PDT dye; III, curcumin/DMSO + laser; IV, curcumin/DMSO only; V, dimethyl sulfoxide (DMSO) only; VI, photothermal therapy (PTT); VII, PTT dye; VIII, control. After treatment, remaining bacterial loads were assessed microbiologically using quantitative real-time polymerase chain reaction analysis. Results: The PDT, PTT, and DMSO treatment methods were associated with statistically significant (p < 0.05) improvements in germ reduction in comparison with the other methods and the untreated control group. The mean percentage reductions were as follows: I (PDT) 93.9%, II (PDT dye) 62.9%, III (curcumin/DMSO + laser) 74.8%, IV (curcumin/DMSO only) 67.9%, V (DMSO) 89.4%, VI (PTT) 86.8%, and VII (PTT dye) 66.3%. Conclusions: The commercially available PDT and PTT adjuvant treatment systems were associated with the largest statistically significant reduction in periopathogenic bacteria on implant surfaces. However, activation with laser light at a suitable wavelength is necessary to achieve the bactericidal effects. The use of curcumin as a photosensitizer for 445 nm laser irradiation did not lead to any improvement in antibacterial efficacy in comparison with rinsing with DMSO solution alone.

Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri-implant diseases

BACKGROUND

Periodontitis and peri-implant diseases are chronic inflammatory conditions occurring in the mouth. Left untreated, periodontitis progressively destroys the tooth-supporting apparatus. Peri-implant diseases occur in tissues around dental implants and are characterised by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. Treatment aims to clean the pockets around teeth or dental implants and prevent damage to surrounding soft tissue and bone, including improvement of oral hygiene, risk factor control (e.g. encouraging cessation of smoking) and surgical interventions. The key aspect of standard non-surgical treatment is the removal of the subgingival biofilm using subgingival instrumentation (SI) (also called scaling and root planing). Antimicrobial photodynamic therapy (aPDT) can be used an adjunctive treatment to SI. It uses light energy to kill micro-organisms that have been treated with a light-absorbing photosensitising agent immediately prior to aPDT.

OBJECTIVES

To assess the effects of SI with adjunctive aPDT versus SI alone or with placebo aPDT for periodontitis and peri-implant diseases in adults.

SEARCH METHODS

We searched the Cochrane Oral Health Trials Register, CENTRAL, MEDLINE, Embase, two other databases and two trials registers up to 14 February 2024.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) (both parallel-group and split-mouth design) in participants with a clinical diagnosis of periodontitis, peri-implantitis or peri-implant disease. We compared the adjunctive use of antimicrobial photodynamic therapy (aPDT), in which aPDT was given after subgingival or submucosal instrumentation (SI), versus SI alone or a combination of SI and a placebo aPDT given during the active or supportive phase of therapy.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures, and we used GRADE to assess the certainty of the evidence. We prioritised six outcomes and the measure of change from baseline to six months after treatment: probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment level (CAL), gingival recession (REC), pocket closure and adverse effects related to aPDT. We were also interested in change in bone level (for participants with peri-implantitis), and participant satisfaction and quality of life.

MAIN RESULTS

We included 50 RCTs with 1407 participants. Most studies used a split-mouth study design; only 18 studies used a parallel-group design. Studies were small, ranging from 10 participants to 88. Adjunctive aPDT was given in a single session in 39 studies, in multiple sessions (between two and four sessions) in 11 studies, and one study included both single and multiple sessions. SI was given using hand or power-driven instrumentation (or both), and was carried out prior to adjunctive aPDT. Five studies used placebo aPDT in the control group and we combined these in meta-analyses with studies in which SI alone was used. All studies included high or unclear risks of bias, such as selection bias or performance bias of personnel (when SI was carried out by an operator aware of group allocation). We downgraded the certainty of all the evidence owing to these risks of bias, as well as for unexplained statistical inconsistency in the pooled effect estimates or for imprecision when evidence was derived from very few participants and confidence intervals (CI) indicated possible benefit to both intervention and control groups. Adjunctive aPDT versus SI alone during active treatment of periodontitis (44 studies) We are very uncertain whether adjunctive aPDT during active treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (mean difference (MD) 0.52 mm, 95% CI 0.31 to 0.74; 15 studies, 452 participants), BOP (MD 5.72%, 95% CI 1.62 to 9.81; 5 studies, 171 studies), CAL (MD 0.44 mm, 95% CI 0.24 to 0.64; 13 studies, 414 participants) and REC (MD 0.00, 95% CI -0.16 to 0.16; 4 studies, 95 participants); very low-certainty evidence. Any apparent differences between adjunctive aPDT and SI alone were not judged to be clinically important. Twenty-four studies (639 participants) observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life. Adjunctive aPDT versus SI alone during supportive treatment of periodontitis (six studies) We were very uncertain whether adjunctive aPDT during supportive treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (MD -0.04 mm, 95% CI -0.19 to 0.10; 3 studies, 125 participants), BOP (MD 4.98%, 95% CI -2.51 to 12.46; 3 studies, 127 participants), CAL (MD 0.07 mm, 95% CI -0.26 to 0.40; 2 studies, 85 participants) and REC (MD -0.20 mm, 95% CI -0.48 to 0.08; 1 study, 24 participants); very low-certainty evidence. These findings were all imprecise and included no clinically important benefits for aPDT. Three studies (134 participants) reported adverse effects: a single participant developed an abscess, though it is not evident whether this was related to aPDT, and two studies observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life.

AUTHORS' CONCLUSIONS

Because the certainty of the evidence is very low, we cannot be sure if adjunctive aPDT leads to improved clinical outcomes during the active or supportive treatment of periodontitis; moreover, results suggest that any improvements may be too small to be clinically important. The certainty of this evidence can only be increased by the inclusion of large, well-conducted RCTs that are appropriately analysed to account for change in outcome over time or within-participant split-mouth study designs (or both). We found no studies including people with peri-implantitis, and only one study including people with peri-implant mucositis, but this very small study reported no data at six months, warranting more evidence for adjunctive aPDT in this population group.

Effect of photodynamic therapy according to differences in photosensitizers on Staphylococcus aureus biofilm on titanium

PURPOSE

This study aimed to evaluate the antimicrobial effect of photodynamic therapy (PDT) against Staphylococcus aureus biofilm on a titanium surface and to compare the differences in the effect of PDT using toluidine blue O (TBO) and methylene blue (MB) as a photosensitizer.

METHODS

The bacterial strain S. aureus ATCC 25,923 was used. Sandblasted and acid-etched (SLA) disks were divided into the following six groups: phosphate buffer saline (PBS), TBO, MB, PBS with laser (PBS + L), TBO with laser (TBO + L), and MB with laser (MB + L). The laser group samples were irradiated by a cold diode laser for 60 s. After treatment, the number of surviving bacteria was calculated by counting the colony-forming units (CFUs) and confocal laser scanning microscopy (CLSM) was applied to observe the bacteria on the disk surface.

RESULTS

The TBO + L and MB + L groups showed significantly lower CFU/ml than the other groups (p < 0.01). The TBO + L group showed significantly lower CFU/ml than the MB + L group (p = 0.032). There was no significant difference between the PBS, TBO, MB, and PBS + L groups. Within the limitations of this in vitro study, PDT with TBO and MB can effectively reduce S. aureus biofilm on SLA titanium surfaces. TBO is more effective than MB as a photosensitizer. PDT with TBO may be applied to the treatment of peri‑implant disease in the future.

One-Year Clinical, Microbiological and Immunological Results of Local Doxycycline or Antimicrobial Photodynamic Therapy for Recurrent/Persisting Periodontal Pockets: A Randomized Clinical Trial

We evaluated, in this study, the clinical, microbiological and immunological effects of local drug delivery (LDD) or photodynamic therapy (PDT), adjunctive to subgingival instrumentation (SI) in persistent or recurrent periodontal pockets in patients enrolled in supportive periodontal therapy (SPT) after one year. A total of 105 patients enrolled in SPT with persistent/recurrent pockets were randomly treated with SI +PDT or SI + LDD or SI (control). The number of treated sites with bleeding on probing (n BOP+), probing pocket depths (PPD), clinical attachment level (CAL), full-mouth plaque and bleeding scores (gingival bleeding index, %bleeding on probing-BOP) was evaluated at baseline and after 12 months. Additionally, eight periodontopathogens and the immunomarkers IL-1β (interleukin)and MMP-8 (matrix metalloprotease) were quantitatively determined using real-time PCR and ELISA, respectively. All three treatments resulted in statistically significant clinical improvements (p < 0.05) without statistically significant intergroup differences (p > 0.05), which were maintained up to 12 months. The presence of BOP negatively affected the PPD and CAL. Moreover, statistically significantly fewer bleeding sites at 12 months were observed in the test groups (p = 0.049). Several periodontopathogens were reduced after 12 months. In conclusion, the present data indicate that in periodontal patients enrolled in SPT, treatment of persistent/recurrent pockets with SI alone or combined with either PDT or LDD may lead to comparable clinical, microbiological and immunological improvements, which are maintained up to 12 months. Secondly, the presence of BOP directly impacts the PPD and CAL.

Effect of Apical Size and Taper on the Efficacy of Root Canal Disinfection With LED Photodynamic Therapy as an Adjunct to Irrigation With Sodium Hypochlorite

Introduction: This study assessed the effect of apical size and taper on the efficacy of root canal disinfection with LED photodynamic therapy (PDT) as an adjunct to irrigation with sodium hypochlorite. Methods: A total of 126 extracted human mandibular molars were divided into 4 groups. The mesiobuccal canal was prepared to size 25/4% in group 1, 25/6% in group 2, 30/4% in group 3, and 30/6% in group 4 using the iRaCe rotary system. A 21-day Enterococcus faecalis biofilm was prepared and used for inoculation of the canals. Each group was randomly divided into 3 subgroups for canal disinfection with 2.5% sodium hypochlorite, sodium hypochlorite plus LED PDT and saline (positive control). Samples from the root canals were obtained with rotary files and cultured. Microbiologic data were analyzed using the Poisson regression test. Results: The bacterial count significantly decreased following disinfection with sodium hypochlorite with/without PDT in all sizes and tapers of preparation compared with the control group (P<0.05). Increasing the apical taper or apical size and the use of PDT as an adjunct did not have a significant effect on the reduction of the bacterial count (P>0.05). However, the apical size and PDT had a significant effect on the number of residual bacteria (P<0.05), and increasing the apical size and conduction of PDT significantly decreased the number of residual bacteria. Conclusion: The apical size and taper and the use of PDT as an adjunct did not have a significant effect on the reduction of the bacterial count. However, increasing the apical size and conduction of PDT as an adjunct to sodium hypochlorite irrigation significantly decreased the number of residual bacteria in the root canal system.

New tendencies in non-surgical periodontal therapy

The aim of this review was to update the evidence of new approaches to non-surgical therapy (NSPT) in the treatment of periodontitis. Preclinical and clinical studies addressing the benefits of adjunctive antimicrobial photodynamic therapy, probiotics, prebiotics/synbiotics, statins, pro-resolving mediators, omega-6 and -3, ozone, and epigenetic therapy were scrutinized and discussed. Currently, the outcomes of these nine new approaches, when compared with subgingival debridement alone, did not demonstrate a significant added clinical benefit. However, some of these new alternative interventions may have the potential to improve the outcomes of NSPT alone. Future evidence based on randomized controlled clinical trials would help clinicians and patients in the selection of different adjunctive therapies.

Clinical and Microbiological Evaluation of Local Doxycycline and Antimicrobial Photodynamic Therapy during Supportive Periodontal Therapy: A Randomized Clinical Trial

The aim of this study was to evaluate the clinical and microbiological effects of subgingival instrumentation (SI) alone or combined with either local drug delivery (LDD) or photodynamic therapy (PDT) in persistent/recurrent pockets in patients enrolled in supportive periodontal therapy (SPT). A total of 105 patients enrolled in SPT were randomly treated as follows: group A (n = 35): SI +PDT and 7 days later 2nd PDT; group B (n = 35): SI+LDD; group C (n = 35): SI (control). Prior intervention, at 3 and 6 months after therapy, probing pocket depths, clinical attachment level, number of treated sites with bleeding on probing (n BOP), full mouth plaque and bleeding scores (gingival bleeding index, %BOP) were recorded. At the same time points, 8 periodontopathogens were quantitatively determined. All three treatments resulted in statistically significant improvements (p < 0.05) of all clinical parameters without statistically significant intergroup differences (p > 0.05). Several bacterial species were reduced in both test groups, with statistically significantly higher reductions for LDD compared to PDT and the control group. In conclusion, the present data indicate that: (a) In periodontal patients enrolled in SPT, treatment of persistent/recurrent pockets with SI alone or combined with either PDT or LDD may lead to comparable clinical improvements and (b) the adjunctive use of LDD appears to provide better microbiological improvements for some periodontal pathogens than SI alone or combined with PDT.

Efficacy of antimicrobial photodynamic therapy (aPDT) for nonsurgical treatment of periodontal disease: a systematic review

Although the standard treatment for periodontal disease is based on scaling and root planing (SRP), the use of antimicrobial photodynamic therapy (aPDT) has been studied as a complement to obtain better clinical results. The purpose of this study was to evaluate the effect of aPDT as adjuncts to SRP, compared with SRP alone, on clinical parameters of chronic periodontal patients. Only randomized controlled trials with at least 3-month follow-ups, of SRP alone and in association with aPDT, were included. The MEDLINE (PubMed), Google Scholar, and LILACS databases were searched for articles published up to July 2020. Random-effects meta-analyses were conducted for clinical attachment level (CAL) and probing pocket depth (PPD) change after treatment. Of 141 potentially relevant papers, 22 were included. The association between SRP and aPDT promoted a significant CAL gain and PPD reduction. Periodontal treatment was partially improved by aPDT, and a favorable effect of indocyanine green-mediated aPDT was observed, and high concentrations of phenothiazine chloride presented clinical improvement as well.

Commercial Local Pharmacotherapeutics and Adjunctive Agents for Nonsurgical Treatment of Periodontitis: A Contemporary Review of Clinical Efficacies and Challenges

Periodontal infections tend to be site-specific, mostly confined to the periodontal pocket. With the surge of antibiotic-resistant bacteria, the trend is shifting towards other therapeutic modalities, especially locally delivered approaches that include other pharmacotherapeutic drugs and medical devices. This narrative review aimed to provide insights into the clinical efficacy of local drug delivery and adjunctive agents used in nonsurgical management of periodontitis. Electronic (PubMed/MEDLINE, CENTRAL, and EMBASE) and bibliographic searches of past systematic reviews were carried out to identify previous publications on the topic. Only relevant literature and randomized controlled trials published in English were selected. In addition, a literature review was developed based on the selected articles. Experimental drugs or agents were excluded. This review highlights the clinically proven and commercially available therapeutic agents related to the management of periodontal disease with comparisons of their clinical efficacies and challenges. A vast array of commercial local pharmacotherapeutic agents had been clinically tested, but the methodologies and clinical results varied within and between each agent used, causing difficulty in drawing conclusions and providing support to the superiority of one agent over another. Considering the benefit-cost ratio with the modest clinical results, the long-term usefulness of these agents remains debatable.

Comparison of different laser-based photochemical systems for periodontal treatment

PURPOSE

The main aim in periodontitis treatment is to remove supragingival and subgingival biofilm. Mechanical treatment to eliminate pathogenic bacteria is limited by morphological conditions on the root surface. This study assessed the antibacterial effectiveness of different laser-based photochemical systems, particularly a novel curcumin-based option.

METHODS

Ninety-one titanium bars were inoculated with an artificial biofilm of common pathogenic periodontal bacteria and inserted into an artificial periodontal pocket model. The following groups (n = 13) were tested: 1, curcumin solution plus SLB laser irradiation (C + L; 445 nm, 0.6 W, 25% duty cycle, 100 Hz, 10 s); 2, curcumin solution (Cur); 3, dimethyl sulfoxide solution (DMSO); 4, SiroLaser Blue (SLB) - laser irradiation (445 nm, 0.6 W, 25% duty cycle, 100 Hz, 10 s); 5, antimicrobial photodynamic therapy (aPDT); 6, antimicrobial photothermal therapy (aPTT); 7, control. The samples were stored in Eppendorf tubes and analyzed microbiologically using quantitative real-time polymerase chain reaction (PCR). The main parameter for analyzing group differences was the total bacterial load. Statistical analysis was performed with nonparametric methods.

RESULTS

Statistically significant reductions in bacterial count were observed in all experimental groups (p < 0.05). The mean percentage reductions were as follows: SLB, 95.03%; aPDT, 83.91%; DMSO, 95.69%; C + L, 97.15%. No statistically significant differences in bacteria reduction were observed for laser alone (SLB), DMSO, or curcumin with or without additional laser irradiation.

CONCLUSIONS

The greatest antibacterial efficacy was observed in samples treated with aPTT. Using curcumin as a photosensitizing agent for 445 nm laser irradiation did not result in improved antibacterial effectiveness in comparison with laser alone.

Photodynamic therapy in endodontics

Photodynamic therapy (PDT) is a treatment modality that was initiated in 1900; however, it was not until the last decade that PDT regained attention for its several favourable features during the treatment of microbial infections in endodontics. Recently, several papers advocated its use for root canal treatment. The concept of photodynamic inactivation requires microbial exposure to either exogenous or endogenous photosensitizer molecules, followed by visible light energy, typically wavelengths in the red/near-infrared region that cause the excitation of the photosensitizers resulting in the production of singlet oxygen and other reactive oxygen species that react with intracellular components and consequently produce cell inactivation and death. Recently, PDT has been suggested as a promising effective adjunct to standard antimicrobial intracanal cleaning and shaping for the treatment of periapical lesions. Current publications tested PDT in terms of bacterial load reduction in vivo, in vitro and ex vivo, showing promising results. The purpose of this article was to review the existing literature on PDT in the endodontic field regarding its mechanism of action, photosensitizers and light sources, limitations and clinical procedures. Although positive results have been demonstrated in vitro, there are considerably fewer in vivo investigations. In conclusion, more in vivo studies are needed on the use of antimicrobial PDT in root canal treatment.

The effects of a desiccant agent in the treatment of chronic periodontitis: a randomized, controlled clinical trial

OBJECTIVE

Chemotherapeutic agents have been widely used as adjuncts for the treatment of chronic periodontitis (CP). This study investigated and compared a desiccant agent as an adjunct to scaling and root planing (SRP) versus SRP alone for the treatment of CP.

MATERIALS AND METHODS

Thirty-six patients with CP were studied. Using a split-mouth design, the maxillary right and left quadrants were randomly assigned to SRP plus desiccant (Hybenx® EPIEN Medical, Inc. St. Paul, MN, USA) or SRP alone. Patients were examined on a regular basis for clinical, microbiological, and inflammatory mediator changes over a 1-year period. Clinical attachment level (CAL) was the primary outcome variable. In addition, the red complex bacteria and gingival crevicular fluid (GCF) inflammatory mediators were monitored.

RESULTS

Compared to baseline, both treatments demonstrated an improvement in periodontal parameters. Compared to SRP alone, SRP plus desiccant yielded a significant improvement in probing depth (PD) (SRP: 2.23 ± 0.31 mm vs. desiccant: 3.25 ± 0.57 mm, p < 0.05), CAL (SRP: 3.16 ± 0.29 mm vs. desiccant: 4.21 ± 0.34 mm, p < 0.05 mm) and bleeding on probing (BOP) (SRP: 4.56 ± 1.5% vs. desiccant: 34.23 ± 4.2%, p < 0.001) at 12 months. Similarly, in the SRP plus desiccant group, the bacteria of the red complex were significantly reduced (p < 0.05); and the level of inflammatory mediators was significantly reduced (p < 0.003) compared to SRP alone.

CONCLUSIONS

SRP plus the desiccant resulted in a greater reduction in clinical, microbial and inflammatory mediators compared to SRP alone.

CLINICAL RELEVANCE

Desiccant, when combined to SRP, was demonstrated as a significant approach to control the levels of certain periodontal pathogens, inflammatory mediators in patients with CP.

Clinical effects of photodynamic therapy as an adjunct to full-mouth ultrasonic scaling and root planing in treatment of chronic periodontitis

Background and aims

Photodynamic therapy (PDT) is a potential strategy to eliminate infection in the specific tissue. It uses lower-power laser to activate a photosensitizing agent. Studies have shown the benefit of PDT in the periodontal treatment. The aim of this study was to evaluate the periodontal changes after applying PDT as an adjunct to one visit full-mouth SRP (scaling and root planing) with subgingival piezoelectric ultrasonic scaler compared with full-mouth SRP alone.

Methods

A split-mouth randomized clinical trial was designed. Twenty patients with moderate to severe chronic periodontitis were treated with subgingival piezoelectric ultrasonic device alone in control group and adjunct treated with PDT in the test group. Probing pocket depth (PD), clinical attachment level (CAL), plaque index (PI), gingival bleeding index (GBI) and gingival inflammation index (GI) were evaluated at baseline, 1 month, 3 and 6 months after treatment. Only sites with PD ≥ 4 mm at baseline were calculated.

Results

All periodontal parameters were significantly improved in both groups at 1 month, 3 and 6 months after treatment. All parameters in test group were better than that control group, with statistically significant differences of GBI and GI (P < 0.05) at 3 and 6 months after treatment but no statistically significant differences of PD, CAL and PI.

Conclusions

One visit full-mouth ultrasonic SRP seems to have good enough effort for the periodontal status till 6 months. The adjunct treatment of PDT provided positive effect in term of GBI and GI.

The Effects of Diode Laser Therapy as an Adjunct to Scaling and Root Planing in the Treatment of Aggressive Periodontitis: A 1-Year Randomized Controlled Clinical Trial

OBJECTIVE

The aim of this study was to investigate and compare the clinical, microbial, and inflammatory effects of a diode laser as an adjunct to scaling and root planing (SRP) versus SRP alone for the treatment of generalized aggressive periodontitis (GAgP).

METHODS

Using a split-mouth design, 31 patients with GAgP were enrolled in the study. The maxillary right and left quadrants were randomly assigned to SRP+diode laser or SRP alone. Patients were examined on a regular basis for clinical, microbiological, and inflammatory mediator changes over a 1-year period. Clinical attachment level (CAL) was the primary outcome variable chosen. In addition, subgingival biofilm samples and gingival crevicular fluid (GCF) inflammatory mediators were analyzed at each follow-up session.

RESULTS

Compared to baseline, both treatments demonstrated an improvement in periodontal parameters at 1 year. However, SRP+diode laser produced a significant improvement in probing depth (PD; 2.56 ± 0.44 vs. 3.36 ± 0.51 mm, p < 0.05) and CAL (3.47 ± 0.25 vs. 4.11 ± 0.26 mm, p < 0.05) values compared to SRP alone. Similarly, in the SRP+diode laser group, the bacteria of orange complex group were significantly reduced at 30 and 60 days compared to SRP alone. Moreover, SRP+diode laser determined a reduction in mean GCF level of interleukin (IL)-1β and IL-1β/IL-10 ratio at 15 and 30 days compared to SRP alone (p < 0.05).

CONCLUSIONS

At 1 year, SRP+diode laser yielded a significant reduction in some clinical parameters, while microbial and inflammatory mediator changes were not significantly reduced compared to SRP alone.

Effect of photodynamic therapy adjunct to scaling and root planing in periodontitis patients: A randomized clinical trial

BACKGROUND

A randomized split-mouth controlled clinical trial was conducted to evaluate the efficacy of photodynamic therapy (PDT) in reducing Aggregatibacter actinomycetemcomitans (Aa) in periodontitis patients.

METHODS

Twenty patients with periodontitis were recruited for the trial. Following random allocation of either quadrants of the selected jaw to test or control treatment, conventional non-surgical periodontal therapy (NSPT) was performed. In addition, the test side received adjunct photodynamic therapy. Probing depth (PD), clinical attachment level, bleeding on probing (BoP) and plaque scores (PS%) were recorded at phase 0 (baseline), phase 1 (immediately after NSPT), phase 2 (7 days following NSPT), phase 3 (1 month following NSPT) and phase 4 (3 months following NSPT). Subgingival plaque samples for quantification of Aa by real-time polymerase chain reaction was performed at phases 0, 1, 2 and 4.

RESULTS

There was a significant clinical improvement at phases 3 and 4 compared with baseline while BoP reduced significantly only in the test group at phase 4. However, no difference in the quantification of Aa was detected between the groups.

CONCLUSIONS

Within the limits of the study, PDT adjunct to scaling and root planing does not lead to quantitative reduction of Aa in periodontitis patients.

Photodvnamic Therapy in Endodontics

Commonly used irrigants do not always eradicate the entire microbial flora in infected root canals. Therefore, several other strategies, such as photodynamic therapy (PDT) have been developed. Photoactivated disinfection is based on the interaction of a photosensitive antibacterial agent and a light source. It uses a nontoxic dye named photosensitizer (PS) and low-intensity visible light. In oxygen presentation, these combine to produce some cytotoxic species. The PS molecules attach to bacteria membrane. Irradiation with a specific wavelength of the light may lead to the production of singlet oxygen, resulting in rupture of the microbial cell wall. There are several applications for PDT in dentistry. A successful periodontal treatment is based on elimination of bacteria from the infected area. Phenothiazinium PSs have been shown to be highly effective and safe for this purpose. However, scaling/root planing should be performed before the PDT. While performing the PDT, PS should be first injected in the periodontal pocket and allowed to pigment. Then, the special fiber should be inserted 1 mm short of the pocket base and lased. Photodynamic therapy has also been used to disinfect caries dentin before restoration, disinfecting oral tissues before or during surgical procedures, treating denture stomatitis, and treating oral candidiasis in immunocompromised patients. Photodynamic therapy can be used in combination with mechanical instrumentation and chemical antimicrobial agents, such as sodium hypochlo-rite, too. The purpose of this study was to review historical perspective, mechanism of action, and applications of PDT in dentistry and especially in endodontics was reviewed. Furthermore, the effects of PDT on dentin bonding and endo-toxin are discussed.

CLINICAL SIGNIFICANCE

Photodynamic therapy has been advocated to increase the disinfection level of the root canal system.

Efficacy of Antimicrobial Photodynamic Therapy as an Adjunctive to Mechanical Debridement in the Treatment of Peri-implant Diseases: A Randomized Controlled Clinical Trial

Introduction: The purpose of the present study was to assess the clinical effects of anti-microbial photodynamic therapy (PDT) after closed surface scaling in the treatment of peri-implant diseases. Methods: Ten patients with a total of 15 pairs of dental implants, showing clinical and radiographic signs of peri-implant diseases, were included in this study. In each patient, one implant randomly served as control implant and the other served as test implant. The control implants were treated with closed surface scaling only and the test implants received additionally PDT, using light with a wavelength of 630 nm and intensity of 2000 mw/cm² for 120 seconds after application of photosensitizer in peri-implant sulcus. Clinical parameters were evaluated before and 1.5 and 3 months after treatment. Results: Statistical analysis showed significant differences in probing pocket depth (PPD), clinical attachment loss (CAL), bleeding on probing (BOP), and gingival index (GI) at each time point between the two groups. There were no statistically significant changes with respect to any of the parameters in the control group. Complete resolution of BOP at 3 months was achieved in 100% of test implants. At 1.5 and 3 months, there were significant differences in the mean probing depth and CAL gain measurements at implants in the test group. Conclusion: The present study revealed that adjunctive use of PDT following closed surface scaling could lead to clinical improvement of peri-implant diseases. Further studies are necessary to confirm our results.

The Antimicrobial Photodynamic Therapy in the Treatment of Peri-Implantitis

Introduction. The aim of this study is to demonstrate the effectiveness of addition of the antimicrobial photodynamic therapy to the conventional approach in the treatment of peri-implantitis. Materials and Methods. Forty patients were randomly assigned to test or control groups. Patients were assessed at baseline and at six (T1), twelve (T2), and twenty-four (T3) weeks recording plaque index (PlI), probing pocket depth (PPD), and bleeding on probing (BOP); control group received conventional periodontal therapy, while test group received photodynamic therapy in addition to it. Result. Test group showed a 70% reduction in the plaque index values and a 60% reduction in PD values compared to the baseline. BOP and suppuration were not detectable. Control group showed a significative reduction in plaque index and PD. Discussion. Laser therapy has some advantages in comparison to traditional therapy, with faster and greater healing of the wound. Conclusion. Test group showed after 24 weeks a better value in terms of PPD, BOP, and PlI, with an average pocket depth value of 2 mm, if compared with control group (3 mm). Our results suggest that antimicrobial photodynamic therapy with diode laser and phenothiazine chloride represents a reliable adjunctive treatment to conventional therapy. Photodynamic therapy should, however, be considered a coadjuvant in the treatment of peri-implantitis associated with mechanical (scaling) and surgical (grafts) treatments.

Effect of gallium-arsenic laser on photosensitized periodontopathic anaerobic organisms: An in vitro study

BACKGROUND

The mainstay of periodontal therapy is mechanical removal of subgingival plaque. There is considerable interest in supplementing it with the use of antibiotics and antiseptics. Many drawbacks are associated with these adjunctive pharmacological regimens such as development of resistance to antibiotics and disruption of microflora of the gastrointestinal tract. Hence, alternate means of killing subgingival bacteria are clearly desirable. One such method is the use of laser.

AIM

This study aimed to investigate antibacterial capabilities of gallium-arsenic (Ga-As) laser on photosensitized periodontopathic organisms. The three bacteria selected for the study were Porphyromonas gingivalis, Fusobacterium nucleatum, and Prevotella intermedia.

SETTINGS

The subjects for the study were selected from the patients visiting the Department of Periodontics, Karnataka Lingayat Education Society's Institute of Dental Sciences, Belgaum.

DESIGN

In vitro study design.

MATERIALS AND METHODS

Subgingival plaque samples collected from chronic periodontitis patients were cultured anaerobically for 72 h. Predetermined number of colonies of each bacterium was taken and was then divided into cases and control groups. Both groups were photosensitized using toluidine blue O (TBO) dye and the case groups were irradiated with Ga-As laser. Bacterial colonies were then serially diluted and were incubated for subculture. After incubation period, the number of viable bacterial count was performed.

STATISTICAL ANALYSIS

Wilcoxon-signed rank test was carried out to determine significance of reduction on subsequent dilution within the bacterial group. Mann-Whitney U-test was performed to determine the significance of reduction between cases and control of particular bacterial group.

RESULTS

The results revealed substantial reduction in the viable bacterial count. F. nucleatum was found to be most sensitive to killing by laser irradiation followed by P. intermedia and then P. gingivalis. Further, the TBO dye per se did not have any significant bactericidal effect.

CONCLUSION

Photodynamic Therapy may prove to be a promising method for eradicating periodontopathic bacteria in near future.

Removal of black stains from teeth by photodynamic therapy: clinical and microbiological analysis

Black-pigmented bacteria (BPB) are Gram-negative anaerobic, non-motile, proteolytic rods strongly implicated in the pathogenesis of periodontal disease. Although pigments are produced in vitro, black pigmentation is rarely found clinically. However, it may compromise aesthetics and contribute to gingival inflammation. The aim of this report is to describe a clinical case of a 10-year-old boy showing black pigmentation covering all teeth and to propose an alternative therapy for removal of black pigmentation, based on photodynamic therapy (PDT). In order to perform microbiological analysis, plaque samples were collected before and after PDT, and analysed by real-time-PCR (RT-PCR). The results showed a significant reduction in BPB levels after therapy, along with clinical evidence of absence of black pigmentation and reduction in gingival bleeding, although the plaque index remained unaltered. This case showed that PDT is effective for eliminating black pigmentation caused by BPB, without recurrence during a follow-up period of 7 months.

Adjunctive Application of Antimicrobial Photodynamic Therapy in Nonsurgical Periodontal Treatment: A Review of Literature

Periodontal disease is caused by dental plaque biofilms, and the removal of these biofilms from the root surface of teeth plays a central part in its treatment. The conventional treatment for periodontal disease fails to remove periodontal infection in a subset of cases, such as those with complicated root morphology. Adjunctive antimicrobial photodynamic therapy (aPDT) has been proposed as an additional treatment for this infectious disease. Many periodontal pathogenic bacteria are susceptible to low-power lasers in the presence of dyes, such as methylene blue, toluidine blue O, malachite green, and indocyanine green. aPDT uses these light-activated photosensitizer that is incorporated selectively by bacteria and absorbs a low-power laser/light with an appropriate wavelength to induce singlet oxygen and free radicals, which are toxic to bacteria. While this technique has been evaluated by many clinical studies, some systematic reviews and meta-analyses have reported controversial results about the benefits of aPDT for periodontal treatment. In the light of these previous reports, the aim of this review is to provide comprehensive information about aPDT and help extend knowledge of advanced laser therapy.

Novel strategies to fight Candida species infection

In recent years, there has been a significant increase in the incidence of human fungal infections. The increase in cases of infection caused by Candida species, and the consequent excessive use of antimicrobials, has favored the emergence of resistance to conventional antifungal agents over the past decades. Consequently, Candida infections morbidity and mortality are also increasing. Therefore, new approaches are needed to improve the outcome of patients suffering from Candida infections, because it seems unlikely that the established standard treatments will drastically lower the morbidity of mucocutaneous Candida infections and the high mortality associated with invasive candidiasis. This review aims to present the last advances in the traditional antifungal therapy, and present an overview of novel strategies that are being explored for the treatment of Candida infections, with a special focus on combined antifungal agents, antifungal therapies with alternative compounds (plant extracts and essential oils), adjuvant immunotherapy, photodynamic therapy and laser therapy.

Clinical and Microbiological Effects of Photodynamic Therapy Associated with Non-surgical Treatment in Aggressive Periodontitis

Background and aims. The aim of this study was to compare the effectiveness of adjunctive photodynamic therapy (PDT) in the treatment of aggressive periodontitis.

Materials and methods. A total of 24 patients with clinical diagnosis of aggressive periodontitis received scaling and root planing (SRP) for periodontal treatment. In a split-mouth design study, the teeth of one quadrant of each arch with ≥4 mm of probing depth were selected randomly for additional treatment with PDT (test group). PDT was performed with a diode laser beam with a wavelength of 670-690 nm and a power of 75 Mw. The control group consisted of selected teeth of the contralateral quadrant (SRP only). Before any treatment, subgingival plaque samples were collected by an endodontic paper cone for microbiological analysis by real-time polymerase chain reaction (PCR) for detection of Aggregatibacter actinomycetecommitans. Clinical parameters including clinical attachment loss (CAL) as primary outcome, plaque index (PI), bleeding on probing (BOP), probing depth (PD) and gingival recession (REC) were measured at baseline and after 90 days. Inter-group and intra-group statistical analyses were performed.

Results. Treatment groups showed an improvement in all the clinical parameters and a significant reduction in the counts of A. actinomycetecommitans at 90 days compared to baseline (P < 0.05). None of the periodontal parameters exhibited significant differences between the two groups (P > 0.05).

Conclusion. Within the limitations of this study, the results did not show additional benefits from PDT as an adjunctive treatment for patients with aggressive periodontitis.

Laser in dentistry: An innovative tool in modern dental practice

The term LASER is an acronym for ‘Light Amplification by the Stimulated Emission of Radiation’. As its first application in dentistry by Miaman, in 1960, the laser has seen various hard and soft tissue applications. In the last two decades, there has been an explosion of research studies in laser application. In hard tissue application, the laser is used for caries prevention, bleaching, restorative removal and curing, cavity preparation, dentinal hypersensitivity, growth modulation and for diagnostic purposes, whereas soft tissue application includes wound healing, removal of hyperplastic tissue to uncovering of impacted or partially erupted tooth, photodynamic therapy for malignancies, photostimulation of herpetic lesion. Use of the laser proved to be an effective tool to increase efficiency, specificity, ease, and cost and comfort of the dental treatment.

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.

Photodynamic therapy in the treatment of chronic periodontitis: a systematic review and meta-analysis

This meta-analysis was conducted to investigate the efficacy and safety of antimicrobial photodynamic therapy used alone or adjunctive to scaling root planing in patients with chronic periodontitis. The meta-analysis was conducted according to the QUOROM statement and recommendations of the Cochrane Collaboration. An extensive literature search was performed on seven databases, followed by a manual search. Weighted mean differences and 95% confidence intervals were calculated for clinical attachment level, probing depth and gingival recession. The I(2) test was used for inter-study heterogeneity; visual asymmetry inspection of the funnel plot, Egger's regression test and the trim-and-fill method were used to investigate publication bias. At 3 months, significant differences in clinical attachment level (p = 0.006) and probing depth reduction (p = 0.02) were observed for scaling root planing with antimicrobial photodynamic therapy, while no significant differences were retrieved for antimicrobial photodynamic therapy used alone; at 6 months no significant differences were observed for any investigated outcome. Neither heterogeneity nor publication bias was detected. The use of antimicrobial photodynamic therapy adjunctive to conventional treatment provides short-term benefits, but microbiological outcomes are contradictory. There is no evidence of effectiveness for the use of antimicrobial photodynamic therapy as alternative to scaling root planing. Long-term randomized controlled clinical trials reporting data on microbiological changes and costs are needed to support the long-term efficacy of adjunctive antimicrobial photodynamic therapy and the reliability of antimicrobial photodynamic therapy as alternative treatment to scaling root planing.

Energy dose parameters affect antimicrobial photodynamic therapy-mediated eradication of periopathogenic biofilm and planktonic cultures

OBJECTIVE

This study evaluated the in vitro efficacy of a commercially available aPDT system in eradication of the periopathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans in both planktonic and biofilm cultures.

BACKGROUND DATA

Antimicrobial photodynamic therapy (aPDT) is an effective antibacterial approach in vitro; however, few data are available regarding effective light-energy parameters.

MATERIALS AND METHODS

Planktonic and biofilm cultures of periopathogens were exposed to a methylene blue-based formulation and irradiated with a 670-nm nonthermal diode laser. Energy doses were varied from 2.3 to 9.4 J/cm(2) through adjustments in illumination time and a constant power density. Controls consisted of no treatment, light only, and photosensitizer only. Temperature changes were recorded in experimental samples before and after illumination.

RESULTS

aPDT with an energy dose of 9.4 J/cm(2) was effective in eradicating P. gingivalis, F. nucleatum, and A. actinomycetemcomitans in biofilm and planktonic form. Reductions from control in planktonic cultures at this energy dose were 6.8 +/- 0.7, 5.2 +/- 0.6, and 1.9 +/- 0.6 log(10), respectively, whereas biofilm reductions were 4.5 +/- 1.2, 3.4 +/- 1.1, and 4.9 +/- 1.4 log(10). Decreasing the treatment time produced an energy dose-dependent killing effect in both models. Changes in sample temperature did not exceed 3 degrees C under these exposure parameters.

CONCLUSION

This study demonstrated that three important periopathogens are susceptible to aPDT-mediated killing, regardless of whether they are present in planktonic or biofilm form. Furthermore, a clear energy dose-dependence exists with this treatment that should to be taken into account when determining optimal treatment times in clinical application.

Salivary levels of TNF-alpha and IL-6 in patients with denture stomatitis before and after laser phototherapy

OBJECTIVE

The aim of this study was to monitor therapeutic response by determining the level of proinflammatory cytokines TNF-alpha and IL-6 in whole unstimulated saliva in patients with denture stomatitis (DS), before and after laser phototherapy (LPT).

BACKGROUND

DS is an inflammatory condition that occurs in subjects who wear dentures, and it is a common oral mucosal lesion. A potential noninvasive treatment for DS patients is LPT.

MATERIALS AND METHODS

A sample consisting of 40 consecutive subjects was selected on a voluntary basis from patients who presented for the diagnosis and treatment of DS at the Oral Medicine Unit of the Medical Faculty at the University of Rijeka. A clinical examination was performed according to the standard clinical criteria. Lesions described as palatal inflammation were diagnosed as Newton type II denture stomatitis. The patients were randomly assigned to either an experimental group (20 patients receiving real LPT) or a control group (20 patients receiving inactive/placebo laser treatment). In order to determine the salivary levels of TNF-alpha and IL-6, ELISA (Sigma Immunochemicals, St Louis, MO) was performed.

RESULTS

Following treatment with LPT for 4 wk, the levels of TNF-alpha and IL-6 decreased significantly (p < 0.001) and were significantly different from controls (p < 0.001).

CONCLUSION

The results of this study suggest that LPT may be an efficacious choice of therapy.