Antimicrobial photodynamic therapy minimizes the deleterious effect of nicotine in female rats with induced periodontitis

Antimicrobial photodynamic therapy for managing the peri-implant mucositis and peri-implantitis: A systematic review of randomized clinical trials

BACKGROUND

The presence of peri‑implant inflammation including peri‑implant mucositis and peri‑implantitis, is a crucial factor that impacts the long-term stability and success of dental implants. This review aimed to evaluate the safety and effectiveness of antimicrobial photodynamic therapy (aPDT) as an adjuvant therapy option for managing peri‑implant mucositis and peri‑implantitis.

METHODS

We systematically searched the PubMed/MEDLINE, Cochrane Library, Scopus, and Google Scholar databases (no time limitation). The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the quality of the studies was assessed using the Cochrane Collaboration tool.

RESULTS

Of 322 eligible articles, 14 studies were included in this review. The heterogeneity and poor quality of the articles reviewed prevented a meta-analysis. The reviewed articles used a light source (60 s, 1 session) with a wavelength of 635 to 810 nm for optimal tissue penetration. These studies showed improved clinical parameters such as probing depth, bleeding on probing (BOP), and plaque index after aPDT treatment. However, in smokers, BOP increased after aPDT. Compared to conventional therapy, aPDT had a longer-term antimicrobial effect and reduced periopathogens like Porphyromonas gingivalis, as well as inflammatory factors such as Interleukin (IL)-1β, IL-6, and Tumor necrosis factor alpha (TNF-α). No undesired side effects were reported in the studies.

CONCLUSION

Although the reviewed articles had limitations, aPDT showed effectiveness in improving peri‑implant mucositis and peri‑implantitis. It is recommended as an adjunctive strategy for managing peri‑implant diseases, but further high-quality research is needed for efficacy and long-term outcomes.

Superhydrophobic Tipped Antimicrobial Photodynamic Therapy Device for the In Vivo Treatment of Periodontitis Using a Wistar Rat Model

Limited options exist for treatment of periodontitis; scaling and root planing (SRP) are not sufficient to eradicate P. gingivalis and the resulting inflammatory disease. Chlorhexidine (CHX), used as an adjuvant to SRP, may reduce bacterial loads but leads to pain and staining, while evidence for its efficacy is lacking. Antibiotics are effective but can lead to drug-resistance. The rising concern of antibiotic resistance limits the future use of this treatment approach. This study evaluates the efficacy of a novel superhydrophobic (SH) antimicrobial photodynamic therapy (aPDT) device as an adjuvant to SRP for the treatment of periodontitis induced in a Wistar rat in vivo model relative to CHX. The SH-aPDT device comprises an SH silicone rubber strip coated with verteporfin photosensitizer (PS), sterilized, and secured onto a tapered plastic optical fiber tip connected to a red diode laser. The superhydrophobic polydimethylsiloxane (PDMS) strips were fabricated by using a novel soluble template method that creates a medical-grade elastomer with hierarchical surface roughness without the use of nanoparticles. Superhydrophobicity minimizes direct contact of the PS-coated surface with bacterial biofilms. Upon insertion of the device tip into the pocket and energizing the laser, the device generates singlet oxygen that effectively targets and eliminates bacteria within the periodontal pocket. SH-aPDT treatment using 125 J/cm2 of red light on three consecutive days reduced P. gingivalis significantly more than SRP-CHX controls (p < 0.05). Clinical parameters significantly improved (p < 0.05), and histology and stereometry results demonstrated SH-aPDT to be the most effective treatment for improving healing and reducing inflammation, with an increase in fibroblast cells and extracellular matrix and a reduction in vascularization, inflammatory cells, and COX-2 expression. The SH-aPDT approach resulted in complete disease clearance assessed 30 days after treatment initiation with significant reduction of the periodontal pocket and re-formation of the junctional epithelium at the enamel-cementum junction. PS isolation on a SH strip minimizes the potential for bacteria to develop resistance, where the treatment may be aided by the oxygen supply retained within the SH surface.

Nanoparticles incorporated in nanofibers using electrospinning: A novel nano-in-nano delivery system

Nanofibers are cutting-edge drug delivery systems that are being utilised to treat a variety of ailments. Nanofibers are mostly woven by electrospinning techniques that are majorly used in drug delivery, wound dressing, tissue engineering, sensors, etc. They have several limitations that can be addressed by developing nano-in-nano delivery techniques. Nanoparticles are incorporated into nanofibers in these nano-in-nano systems. They offer a lot of benefits over other nanosystems, including the ability to shield drugs from physical deterioration, the ability to provide prolonged drug release, high surface area to volume ratio, increased drug loading capacity and the potential to be employed in critical conditions such as cancer. These nanoparticles can be encapsulated, entrapped, or adsorbed onto nanofibers in a variety of ways. To include nanosystems into nanofibers, a variety of materials and different kinds of nanoparticles can be used. The present review gives an insight to the applications of nano - in - nano drug delivery system for different diseases/disorders. The review also brings forward the current state of these novel delivery systems along with future perspectives.

Antioxidant Effects of Curcumin Gel in Experimental Induced Diabetes and Periodontitis in Rats

This study aimed to evaluate the effect of curcumin gel on antioxidant marker level in experimental induced diabetes and periodontitis (EDP) in rats. Adult Wistar rats were randomized into five groups (20 each): (1) EDP treated with scaling and root planing (SRP) + curcumin gel (CU), (2) EDP treated with CU, (3) EDP treated with SRP, (4) EDP without treatment, and (5) systemically healthy and without ligature (control). Each group was subdivided equally into 4 subgroups of 5 rats. Diabetes was induced by intraperitoneal injection of streptozotocin (STZ), and periodontitis was induced by a ligature. Blood samples were collected by cardiac puncture at 0, 7, 14, and 21 days to assess oxidative stress of malondialdehyde (MDA) and antioxidant enzymes of glutathione peroxidase (GPx), catalase (CAT), and suproxidase dismutase (SOD) levels. The results showed a significant increase in serum MDA and antioxidant enzyme levels in the untreated EDP group compared to the control group ( $p<0.05$ ). The adjuvant use of CU to SRP resulted in a significant reduction of MDA and CAT levels as compared to the SRP group ( $p<0.05$ ); however, significant reduction of GPX and SOD levels can be found only at day 7. It can be concluded that the decreased level of antioxidant enzymes can be construed as a result of decreased oxidative stress by curcumin therapy.

LASER in periodontal treatment: is it an effective treatment or science fiction?

There are several studies that evaluate the use of lasers in periodontal treatment in non-surgical or surgical therapy. However, while several studies showed clinically beneficial effects of some lasers in periodontal treatment, there are few clinical reports of additional advantages of lasers as adjunctive treatments in periodontology. The aim of this paper is to demonstrate and critically analyze the level of scientific evidence of effects of low-level lasers and high-power lasers in periodontology. A narrative review of the studies was carried out in each topic and type of laser or periodontal treatment. In nonsurgical periodontal therapy the results showed that there is an additional clinical benefit when using a diode laser (DL) associated with scaling and root planing (SRP) in patients with moderate to severe periodontitis. The Er:YAG laser seems to be the most suitable for nonsurgical periodontal therapy and promotes the same clinical effects as conventional therapy. In periodontal surgery vaporization of the gingival or mucosal tissue can be carried out with DL, CO2, Nd:YAG, Er:YAG and Er,Cr:YSGG lasers. Photobiomodulation (PBM), mediated by low-level lasers associated with non-surgical periodontal therapy, promotes additional benefits in the short term and accelerates the bone and gingival tissue repair process and also reduces postoperative symptoms of periodontal surgery. The effect of antimicrobial Photodynamic Therapy is relevant in the initial reevaluation periods. Studies have shown controversial results of the use of lasers in periodontics, and this fact may be due to the lack of standard parameters of irradiation in each clinical application.

Comparative effects of different phenothiazine photosensitizers on experimental periodontitis treatment

AIM

The aim of the present study was to compare the effects of the phenothiazine photosensitizers methylene blue (MB), toluidine blue-O (TBO) and butyl toluidine blue (BuTB) in antimicrobial photodynamic therapy (aPDT), as adjuvant therapy to scaling and root planing (SRP) in the treatment of experimental periodontitis (EP) in rats.

MATERIAL AND METHODS

120 Wistar rats underwent ligation around the lower left molar. After seven days, the ligature was removed. The animals were separated into the following groups (n = 15): EP, no treatment; SRP, SRP and irrigation with saline solution; MB, SRP and deposition of MB; TBO, SRP and deposition of TBO; BuTB, SRP and deposition of BuTB; MB-aPDT, SRP and aPDT with MB; TBO-aPDT, SRP and aPDT with TBO and; BuTB-aPDT, SRP and aPDT with BuTB. The aPDT session was performed after SRP, with deposition of the photosensitizer and irradiation with a diode laser (DL; InGaAlP, 660 nm, 40 mW, 60 s, 2.4 J). Histological and histometric analysis was performed.

RESULTS

BuTB-aPDT group had a lesser extent of the inflammatory process compared to the EP, SRP, MB and TBO at all experimental periods (p < 0.05). At 15 days, the aPDT treated groups had a greater bone tissue structure than groups EP and SRP (p < 0.05) The BuTB showed lower Alveolar Bone Loss (ABL) compared to the TBO-aPDT group at 30 days (p < 0.05).

CONCLUSION

aPDT using the photosensitizer BuTB proved to be the adjuvant therapy that most favored the reduction of inflammatory infiltrate in the furcation area and ABL.

Effect of cerebral palsy and dental caries on dental plaque index, salivary parameters and oxidative stress in children and adolescents

PURPOSE

The aim of the present study was to investigate the effect of cerebral palsy and dental caries on dental plaque index, salivary parameters and oxidative stress in children and adolescents.

METHODS

Seventy children and adolescents aged 2-20 years were divided into four groups: neurotypical controls-inactive caries (NCIC; n = 19); neurotypical controls-active caries (NCAC; n = 16); cerebral palsy-inactive caries (CPIC; n = 19); and cerebral palsy-active caries (CPAC; n = 16). The visible dental plaque index was determined after drying the tooth surfaces and without any mechanical or chemical disclosing methods. Salivary pH and buffer capacity were measured 1 hour after collection using a digital pH meter. Saliva was used to evaluate oxidative status based on the levels of reactive species, lipid peroxidation and non-enzymatic antioxidants (reduced glutathione and vitamin C).

RESULTS

The CPIC and CPAC groups had lower salivary pH and a higher visible dental plaque index. CP was also associated with an increase in salivary levels of markers of oxidative stress and the modulation of salivary levels of non-enzymatic antioxidants.

CONCLUSION

Cerebral palsy exerts an influence on the salivary profile, oral health and oxidative stress. The individuals with CP had more acidic saliva and a higher dental plaque index, which were positively correlated with caries activity. CP was associated with high salivary levels of reactive species and lipid peroxidation, demonstrating an imbalance in salivary redox that was particularly associated with caries activity. These factors facilitate the development of oral diseases in individuals with cerebral palsy.

One-step treatment of periodontitis based on a core-shell micelle-in-nanofiber membrane with time-programmed drug release

As a chronic inflammatory disease, periodontitis is responsible for irreversible soft tissue damage and severe alveolar bone resorption. However, curative effects of current therapies are largely confined by the difficulty to simultaneously achieve anti-inflammation and bone regeneration. Also, the dynamic environment in oral cavity easily causes the drugs swallowed or rinsed away by saliva. We report here a one-step treatment based on a core-shell nanofiber membrane fabricated by coaxial electrospinning. Polymeric micelles containing SP600125 were distributed in the shell, while BMP-2 was incorporated in the core. After crosslinking, the nanofiber membrane displayed a prolonged degradation and release period up to 4 weeks. The release of SP600125 was detected at beginning, whereas BMP-2 was not released until day 12. Such a time-programmed release behavior was proved desirable for suppressing the expression of pro-inflammatory factors and enhancing the osteogenic induction in vitro. Further in vivo investigation confirmed that, by simply covering the periodontitis site with our nanofiber membrane, alveolar destruction was largely avoided and bone defects recovered within 2 month. Taken together, we believe that the use of our membrane with sequential release of SP600125 and BMP-2 may become a convenient and highly comprehensive therapy for periodontitis.

Effects of an Er,Cr:YSGG Laser on Bone Regeneration in Critical-Sized Calvarial Defects of Rats Exposed to Inhalation of Cigarette Smoke

Objective: To evaluate the effect of the Er,Cr:YSGG laser on healing of critical-sized calvarial defects (CSDs) in rats submitted to inhalation of cigarette smoke. Background: Smoking has been implicated with the delay in the bone healing after osteotomy procedures, then the use of the Er,Cr:YSGG laser for osteotomy in smokers could be an alternative to the conventional drills. Methods: One hundred animals were randomly allocated into four groups: trephine-the CSDs were made with a trephine drill in healthy rats; Er,Cr:YSGG-the CSDs were made with the Er,Cr:YSGG laser in healthy rats; Trephine-S-the CSDs were made with a trephine drill in rats exposed to cigarette smoke; and Er,Cr:YSGG-S-the CSDs were made with the Er,Cr:YSGG laser in rats exposed to cigarette smoke. The inhalation of cigarette smoke started 7 days before the surgical procedure until euthanasia (immediately, 7, 15, 30, or 60 days after the surgical procedure). A histometric analysis and a histological description were performed to evaluate (1) the residual linear lengths and bone formation in the CSDs; (2) the quality of bone healing. Results: The use of Er,Cr:YSGG laser induces more bone formation compared with the trephine in smokers; however, the closure of the CSD was only superior in the Er,Cr:YSGG-S group compared to the Trephine-S group at the 60-day period. Conclusions: The use of the Er,Cr:YSGG laser stimulated the bone repair process after osteotomy procedures in animals submitted to exposure of inhalation of cigarette smoke.

The influence of LLLT applied on applied on calvarial defect in rats under effect of cigarette smoke

Objective

Considering the global public health problem of smoking, which can negatively influence bone tissue repair, the aim of this study is to analyze the influence of photobiomodulation therapy (PBM) on calvaria defects created surgically in specimens under the effect of cigarette smoke and analyzed with use of histomorphometric and immunohistochemistry techniques.

Methodology

Calvaria defects 4.1 mm in diameter were surgically created in the calvaria of 90-day-old rats (n=60) that were randomly divided into 4 experimental groups containing 15 animals each: control group (C), smoking group (S), laser group (L), and smoke associated with laser group (S+L). The animals were subjected to surgery for calvaria defects and underwent PBM, being evaluated at 21, 45, and 60 days post-surgery. The specimens were then processed for histomorphometric and immunohistochemistry analyses. The area of bone neoformation (ABN), percentage of bone neoformation (PBNF), and the remaining distance between the edges of the defects (D) were analyzed histometrically. Quantitative analysis of the TRAP immunolabeled cells was also performed. The data were subjected to analysis of variance (ANOVA) in conjunction with Tukey’s test to verify the statistical differences between groups (p<0.05).

Results

The smoking group showed less ABN compared to the other experimental groups in all periods, and it also showed more D at 21 days compared to the remaining groups and at 45 days compared to the laser group. The smoking group showed a lower PNBF compared to the laser group in all experimental periods and compared to smoking combined with LLLT group at 21 days.

Conclusions

PBM acted on bone biomodulation, thus stimulating new bone formation and compensating for the negative factor of smoking, which can be used as a supportive therapy during bone repair processes.

Adjunctive antimicrobial photodynamic therapy using methylene blue/ethanol formulation in experimental periodontitis in diabetic rats: short-term results

The aim of this study was to evaluate the effect of an MB experimental formulation (ethanol 20%) in aPDT used as an adjuvant to scaling and root planing (SRP) in the periodontal treatment of diabetic rats. Forty male Wistar rats received streptozotocin-intraperitonial injections to induce diabetes. After 14 days, 5 animals were allocated in the non-ligate group (NLG), and 35 animals received ligature at the first right mandibular molar to induce periodontitis. After 7 days, the ligature was removed and the animals were randomized into 4 groups: LG (without treatment, n = 5), SRPG (SRP, n = 10), aPDTW (SRP+aPDT-MB/water, n = 10), and aPDTEt (SRP + aPDT-MB/water/ethanol/carboxymethylcellulose, n = 10). Animals were euthanized after 7 days. Data of bone loss (BL) area, degree of inflammatory cell response, and collagen fibers percentages were statistically analyzed (p < 0.05). Percentage of animals that presented mild and severe inflammatory infiltrate was 10% and 40% for SRPG, 20% and 30% for aPDTW, and 50% and 0% for aPDTEt, respectively. BL area (mm²) was statistically higher in the LG (0.39 ± 0.15) than NLG (0.05 ± 0.02). aPDTEt showed the lowest value of BL (0.08 ± 0.03), followed by aPDTW (0.21 ± 0.15) and SRPG (0.31 ± 0.18). Statistical differences were verified between aPDTEt and SRPG. In relation to the LG, aPDTEt, aPDTW, and SRPG recovered the equivalent 80%, 46%, and 20% of the BL. aPDTEt showed collagen content statistically higher than SRPG and LG, and presented higher mean values than NLG (p > 0.05). Our findings showed aPDTEt presented promising results. aPDT using MB/ethanol can have potential as an adjunctive periodontal treatment in diabetics.

Photodynamic therapy versus systemic antibiotic for the treatment of periodontitis in a rat model

BACKGROUND

To compare the therapeutic effect of photodynamic therapy (PDT) with Toluidine blue O hydrogel versus systemic antibiotic (SA) in treating periodontitis on rats.

METHODS

Thirty-two Wistar rats were divided into four groups and treated differently: Negative control (NC) group, normal rats; positive control (PC) group, rats with periodontitis; SA group, rats with periodontitis treated with systemic antibiotic; PDT group, rats with periodontitis treated with PDT. After treatment, gingival sulcus bacterial load was measured by counting the colony forming units per milliliter (CFU mL^-1 ). The tooth and periodontal tissues were histologically processed to analyze histological and immunohistochemical profile. Gingival samples were obtained to quantify interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels.

RESULTS

Gingival sulcus bacteria load is significantly lower in PDT group compared with the SA group. The histological analysis showed that some extremely effective repair signs of periodontal tissue were presented in PDT group, such as no periodontal pocket, no bone resorption, few inflammatory cells, massive fibroblasts and collagen fibers. Several effective repair signs of periodontal tissue were also observed in SA group, such as shallow periodontal pocket, small amount of inflammatory cells, substantial fibroblasts and collagen fibers. There were lower cyclooxygenase-2, matrix metalloproteinase -8 (MMP-8) and RANK immunolabeling, higher osteoprotegerin immunolabeling in PDT group compared with SA group. The IL-1β and TNF-α levels in PDT group were lower than those in NC group, but higher than those in SA group.

CONCLUSION

PDT was effective to treat experimental periodontitis and was superior to systemic metronidazole as a treatment for periodontitis.

Antimicrobial photodynamic therapy with photosensitizer in ethanol improves oxidative status and gingival collagen in a short-term in periodontitis

BACKGROUND

This study evaluated the antimicrobial photodynamic therapy (aPDT) effects using the methylene blue (MB) in ethanol 20% on systemic oxidative status and collagen content from gingiva of rats with periodontitis.

METHODS

Rats were divided into five experimental groups: NC (negative control; no periodontitis); PC (positive control; periodontitis without any treatment); SRP (periodontitis and scaling and root planing), aPDT I (periodontitis and SRP+aPDT+MB solubilized in water), and aPDT II (periodontitis and SRP+aPDT+MB solubilized in ethanol 20%). After 7days of removal of the ligature, the periodontal treatments were performed. At 7/15/30days, gingival tissue was removed for morphometric analysis. The erythrocytes were used to evaluate systemic oxidative status.

RESULTS

PC group showed higher lipoperoxidation levels at 7/15/30days. aPDT indicated a protective influence in erythrocytes at 15days observed by the elevation in levels of systemic antioxidant defense. aPDT II group was the only one that restored the total collagen area in 15days, and recovered the type I collagen area at the same time point.

CONCLUSIONS

aPDT as an adjunct to the SRP can induce the systemic protective response against oxidative stress periodontitis-induced and recover the gingival collagen, thus promoting the healing periodontal, particularly when the MB is dissolved in ethanol 20%.