The short-term effects of low-level lasers as adjunct therapy in the treatment of periodontal inflammation

OBJECTIVES

The aim of this split-mouth, double-blind controlled clinical trial was to study the effects of irradiation with low-level lasers as an adjunctive treatment of inflamed gingival tissue.

MATERIALS AND METHODS

Seventeen patients with moderate periodontitis were included. After clinical examination, all teeth were scaled and root planed (SRP). One week after SRP, we took samples of gingival crevicular fluid (GCF) and subgingival plaque. The laser therapy was started 1 week later and continued once a week for 6 weeks. One side of the upper jaw was treated with active laser and the other with a placebo. The test side was treated with two low-level lasers having wavelengths of 635 and 830 nm. The patients then underwent another clinical examination with sampling of GCF and plaque. The GCF samples were analysed for elastase activity, interleukin-1beta (IL-1beta) and metalloproteinase-8 (MMP-8). We examined the subgingival plaque for 12 bacteria using DNA probes.

RESULTS

The clinical variables i.e. probing pocket depth, plaque and gingival indices were reduced more on the laser side than on the placebo one (p<0.01). The decrease in GCF volume was also greater on the laser side, 0, 12 microl, than on the placebo side, 0.05 microl (p=0.01). The total amount of MMP-8 increased on the placebo side but was slightly lower on the laser side (p=0.052). Elastase activity, IL-1beta concentration and the microbiological analyses showed no significant differences between the laser and placebo sides.

CONCLUSION

Additional treatment with low-level lasers reduced periodontal gingival inflammation.

Antimicrobial Photodynamic Therapy in the Non-Surgical Treatment of Aggressive Periodontitis: A Preliminary Randomized Controlled Clinical Study

BACKGROUND

The treatment of aggressive periodontitis has always presented a challenge for clinicians, but there are no established protocols and guidelines for the efficient control of the disease.

METHODS

Ten patients with a clinical diagnosis of aggressive periodontitis were treated in a split-mouth design study to either photodynamic therapy (PDT) using a laser source with a wavelength of 690 nm associated with a phenothiazine photosensitizer or scaling and root planing (SRP) with hand instruments. Clinical assessment of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and relative clinical attachment level (RCAL) were made at baseline and 3 months after treatment with an automated periodontal probe.

RESULTS

Initially, the PI was 1.0 +/- 0.5 in both groups. At the 3-month evaluation, the plaque scores were reduced and remained low throughout the study. A significant reduction of GI and BOP occurred in both groups after 3 months (P <0.05). The mean PD decreased in the PDT group from 4.92 +/- 1.61 mm at baseline to 3.49 +/- 0.98 mm after 3 months (P <0.05) and in SRP group from 4.92 +/- 1.14 mm at baseline to 3.98 +/- 1.76 mm after 3 months (P <0.05). The mean RCAL decreased in the PDT group from 9.93 +/- 2.10 mm at baseline to 8.74 +/- 2.12 mm after 3 months (P <0.05), and in the SRP group, from 10.53 +/- 2.30 mm at baseline to 9.01 +/- 3.05 mm after 3 months.

CONCLUSION

PDT and SRP showed similar clinical results in the non-surgical treatment of aggressive periodontitis.

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

Subgingival plaque samples from patients with chronic periodontitis were exposed to light from a 7.3 mW Helium/Neon laser for 30 s in the presence and absence of 50 micrograms/ml toluidine blue O as a photosensitizer. Viable counts of various groups and species of bacteria were carried out before and after irradiation. The median numbers of viable bacteria initially present in the 30-microliters aliquots irradiated were 1.13 x 10(5) cfu (aerobes), 4.08 x 10(5) cfu (anaerobes), 4.92 x 10(3) cfu (black-pigmented anaerobes), 4.75 x 10(2) cfu (Porphyromonas gingivalis), 6.15 x 10(3) cfu (Fusobacterium nucleatum) and 1.7 x 10(4) cfu (streptococci). The dye/laser combination achieved significant reductions in the viability of these organisms, the median reductions in the viable counts being 91.1% for aerobes, 96.6% for anaerobes, 100% for black-pigmented anaerobes, P. gingivalis and F. nucleatum and 94.2% for streptococci. Overall, the viability of bacteria in the 20 plaque samples was not significantly decreased by the dye alone. However, in a small minority of samples there were indications of light-independent, dye-induced toxicity. Low-power lasers, in conjunction with appropriate photosensitizers, may be a useful adjunct to mechanical debridement in the treatment of inflammatory periodontal diseases if a similar effectiveness against subgingival plaque bacteria can be achieved in vivo.

Effect of gallium arsenide diode laser on human periodontal disease: a microbiological and clinical study

BACKGROUND AND OBJECTIVE

The present study is aimed to describe short-term results on selected microbiological and clinical parameters obtained by treatment with soft laser in conjunction with methylene blue and/or mechanical subgingival debridement in human periodontal disease.

STUDY DESIGN/MATERIALS AND METHODS

Ten patients, in whom each dental quadrant was randomly designated to receive one of four types of treatment procedures, were included in the study. Groups of quadrants received: scaling/root planing (SRP); laser application (L); SRP combined with L (SRP/L); oral hygiene instructions (OHI). Four single rooted teeth (one in each quadrant), having an interproximal site with a probing depth of 4 mm mesio-buccally, were selected in each patient. The selected teeth were first assessed for microbiological (one site/tooth) and then for clinical variables (six sites/tooth). Supragingival irrigation with methylene blue was performed prior to laser application. The microbiological (proportions of obligate anaerobes) and clinical measurements (plaque and gingival indices, bleeding on probing, probing pocket depth) were evaluated over a period of 32 days.

RESULTS

Only the SRP/L and SRP groups provided significant reductions in the proportions of obligate anaerobes before and after treatments with no significant differences in between. Parallel to the microbiological changes, both SRP/L and SRP resulted in similar clinical improvements, whereas L alone revealed a limited effect similar to OHI.

CONCLUSION

Within the limits of this study, methylene blue/soft laser therapy provided no additional microbiological and clinical benefits over conventional mechanical debridement.

Conventional versus laser-assisted therapy of periimplantitis: a five-year comparative study

Between 1994 and 1999, 50 patients were treated with either profound parodontopathy (30) or periimplantitis (20). Half of each of the two groups of patients was treated conventionally, and the other half was treated with laser support. Before the operation, microbiological examinations were carried out, in addition to registering the clinical findings and taking x-rays. These procedures were repeated after the operation, and again after 6, 12, 24, 36, 48, and 60 months. The surgical part of therapy for each half of the patient groups included surface decontamination with diode laser light (1-watt output, maximum of 20 seconds) in addition to conventional procedures. The values of the laser-supported therapy were lower than those specified in the relevant literature. The relapse rate of the two diseases (13% for the periimplantitis and 23% for the parodontopathy group) after 5 years was lower than the comparative values of researched literature where decontamination was not included in the therapy. We think that integrating diode laser light decontamination in the approved treatment schemes for periimplantitis and parodontitis contributes considerably to the success of this therapy.

Periodontal treatment with an Er:YAG laser or scaling and root planing. A 2-year follow-up split-mouth study

BACKGROUND

Non-surgical periodontal treatment with an Er:YAG laser has been shown to result in significant clinical attachment level gain; however, clinical results have not been established on a long-term basis following Er:YAG laser treatment. Therefore, the aim of the present study was to present the 2-year results following non-surgical periodontal treatment with an Er:YAG laser or scaling and root planing.

METHODS

Twenty patients with moderate to advanced periodontal destruction were treated under local anesthesia, and the quadrants were randomly allocated in a split-mouth design to either 1) Er:YAG laser (ERL) using an energy level of 160 mJ/pulse and 10 Hz, or 2) scaling and root planing (SRP) using hand instruments. The following clinical parameters were evaluated at baseline and at 1 and 2 years after treatment: plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL). Subgingival plaque samples were taken at each appointment and analyzed using dark-field microscopy for the presence of cocci, non-motile rods, motile rods, and spirochetes. The primary outcome variable was CAL. No statistically significant differences between the groups were found at baseline. Power analysis to determine superiority of ERL treatment showed that the available sample size would yield 99% power to detect a 1 mm difference.

RESULTS

The sites treated with ERL demonstrated mean CAL change from 6.3 +/- 1.1 mm to 4.5 +/- 0.4 mm (P < 0.001) and to 4.9 +/- 0.4 mm (P < 0.001) at 1 and 2 years, respectively. No statistically significant differences were found between the CAL mean at 1 and 2 years postoperatively. The sites treated with SRP showed a mean CAL change from 6.5 +/- 1.0 mm to 5.6 +/- 0.4 mm (P < 0.001) and to 5.8 +/- 0.4 mm (P < 0.001) at 1 and 2 years, respectively. The CAL change between 1 and 2 years did not present statistically significant differences. Both groups showed a significant increase of cocci and non-motile rods and a decrease in the amount of spirochetes. However, at the 1- and 2-year examination, the statistical analysis showed a significant difference for the CAL (P < 0.001, respectively) between the 2 treatment groups.

CONCLUSION

It was concluded that the CAL gain obtained following non-surgical periodontal treatment with ERL or SRP can be maintained over a 2-year period.

An evaluation of the Nd:YAG laser in periodontal pocket therapy

The aim of this study was to determine whether the Nd:YAG laser energies of 50 and 80 mJ at 10 pulses per second (pps) were capable of improving the clinical parameters associated with periodontal disease. These energy settings were chosen as previous work indicated that higher values would damage root surfaces and that 80 mJ had an in-vitro bactericidal effect. Eighty periodontally affected sites in teeth scheduled for extraction from 11 patients with adult periodontitis were randomly placed in one of the following four treatment groups: 1. laser treatment at 50 mJ, 10 pps for 3 minutes; 2. laser treatment at 80 mJ, 10 pps for 3 minutes; 3. scaling and 4. untreated control. Probing depth, bleeding on probing (BOP), plaque index, gingival index and gingival crevicular fluid (GCF) volume were measured at baseline and week 6. Baseline subgingival microbiological samples were collected, then repeated immediately after treatment and at week 6 to assess the total anaerobic colony forming units (CFU). Only the scaling group showed a significant reduction in pocket depth and BOP (P < 0.001). The microbial samples taken immediately after scaling and laser at 80 mJ and 10 pps treatments showed a significant reduction in total CFU compared with the baseline (P < 0.01), which was sustained only in the scaling group until week 6. Electron microscopy did not reveal any heat damage on the root surfaces. This study demonstrated that application of Nd:YAG laser pulses of 50 mJ and 80 mJ failed to improve the clinical and microbiological parameters of periodontal disease.

Clinical and histological healing pattern of peri-implantitis lesions following non-surgical treatment with an Er:YAG laser

BACKGROUND AND OBJECTIVES

The aim of the present study was to assess clinical and histo-pathological healing pattern of peri-implantitis lesions following non-surgical treatment with an Er:YAG laser (ERL).

STUDY DESIGN/MATERIALS AND METHODS

Twelve patients suffering from peri-implantitis (n = 12 implants) received a single episode of non-surgical instrumentation using ERL (12.7 J/cm2). Assessment of clinical parameters (plaque index (PI), bleeding on probing (BOP), probing pocket depth, gingival recession (GR), and clinical attachment level (CAL)), surgical defect examination, and histo-pathological examination of peri-implant tissue biopsies was performed after 1, 3, 6, 9, 12, and 24 months.

RESULTS

All patients exhibited improvements of all clinical parameters investigated. However, histo-pathological examination of tissue biopsies revealed a mixed chronic inflammatory cell infiltrate (macrophages, lymphocytes, and plasma cells) which seemed to be encapsulated by deposition of irregular bundles of fibrous connective tissue showing increased proliferation of vascular structures.

CONCLUSION

It was concluded that a single course of non-surgical treatment of peri-implantitis using ERL may not be sufficient for the maintenance of failing implants.

Comparison of Nd:YAG laser versus scaling and root planing in periodontal therapy

BACKGROUND

The Nd:YAG laser has recently been used in the treatment of periodontal disease. However, although a clinical reduction of probing depth and gingival inflammation to this new approach has been reported, it has not been fully evaluated. Interleukin-1 beta (IL- 1beta), a potent stimulator of bone resorption, has been identified in gingival crevicular fluid (GCF), which is closely associated with periodontal destruction. The aim of this study was to compare the effects of Nd:YAG laser treatment versus scaling/root planing (SRP) treatment on crevicular IL-1beta levels in 52 sampled sites obtained from 8 periodontitis patients.

METHODS

One or 2 periodontitis-affected sites with a 4 to 6 mm probing depth and horizontal bone loss from 3 adjacent single-root teeth in each of 4 separate quadrants were selected from patients for clinical documentation and IL-1beta assay. Sampling site(s) from each diseased quadrant was randomly assigned to one of the following groups: 1) subgingival laser treatment (20 pps, 150 mJ) only; 2) SRP only; 3) laser treatment first, followed by SRP 6 weeks later; or 4) SRP first, followed by laser therapy 6 weeks later. The GCF was collected and the amount of IL-1beta was assayed by enzyme-linked immunosorbent assay (ELISA). Clinical parameters and GCF were measured at baseline and biweekly after therapy for 12 weeks.

RESULTS

An obvious clinical improvement (marked decrease in the number of diseased sites with gingival index > or =2) and reduction of crevicular IL- 1beta were found in all groups. The level of IL- 1beta was significantly lower in the SRP group (P = 0.035) than in the laser therapy group for the duration of the 12 weeks. The laser combined SRP therapy group showed a further reduction of IL- 1beta (6 to 12 weeks after treatment) than either laser therapy alone or SRP combined laser therapy.

CONCLUSIONS

Our data suggest that laser therapy appeared to be less effective than traditional SRP treatment. Of the 4 treatment modalities, inclusion of SRP was found to have a superior IL- 1beta response, when compared to other therapies without it. In addition, no additional benefit was found when laser treatment was used secondary to traditional SRP therapy.

New Irradiation Method with Indocyanine Green-Loaded Nanospheres for Inactivating Periodontal Pathogens

Antimicrobial photodynamic therapy (aPDT) has been proposed as an adjunctive strategy for periodontitis treatments. However, use of aPDT for periodontal treatment is complicated by the difficulty in accessing morphologically complex lesions such as furcation involvement, which the irradiation beam (which is targeted parallel to the tooth axis into the periodontal pocket) cannot access directly. The aim of this study was to validate a modified aPDT method that photosensitizes indocyanine green-loaded nanospheres through the gingivae from outside the pocket using a diode laser. To establish this trans-gingival irradiation method, we built an in vitro aPDT model using a substitution for gingivae. Irradiation conditions and the cooling method were optimized before the bactericidal effects on Porphyromonas gingivalis were investigated. The permeable energy through the gingival model at irradiation conditions of 2 W output power in a 50% duty cycle was comparable with the transmitted energy of conventional irradiation. Intermittent irradiation with air cooling limited the temperature increase in the gingival model to 2.75 °C. The aPDT group showed significant bactericidal effects, with reductions in colony-forming units of 99.99% after 5 min of irradiation. This effect of aPDT against a periodontal pathogen demonstrates the validity of trans-gingival irradiation for periodontal treatment.

Low-level lasers as an adjunct in periodontal therapy in patients with diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) increases the risk of periodontitis, and severe periodontitis often coexists with severe DM. The proposed dual pathway of tissue destruction suggests that control of chronic periodontal infection and gingival inflammation is essential for achieving long-term control of DM. The purpose this study is to evaluate the effects of low-level laser therapy (LLLT) by exfoliative cytology in patients with DM and gingival inflammation.

SUBJECTS AND METHODS

Three hundred patients were divided in three equal groups: Group 1 consisted of patients with periodontitis and type 1 DM, Group 2 of patients with periodontitis and type 2 DM, and Group 3 of patients with periodontitis (control group). After oral examination, smears were taken from gingival tissue, and afterward all of the patients received oral hygiene instructions, removal of dental plaque, and full-mouth scaling and root planing. A split-mouth design was applied; on the right side of jaws GaAlAs LLLT (670 nm, 5 mW, 14 min/day) (model Mils 94; Optica Laser, Sofia, Bulgaria) was applied for five consecutive days. After the therapy was completed, smears from both sides of jaws were taken. The morphometric analysis was done using the National Institutes of Health Image software program and a model NU2 microscope (Carl Zeiss, Jena, Germany).

RESULTS

Investigated parameters were significantly lower after therapy compared with values before therapy. After therapy on the side subjected to LLLT, there was no significantly difference between patients with DM and the control group.

CONCLUSIONS

It can be concluded that LLLT as an adjunct in periodontal therapy reduces gingival inflammation in patients with DM and periodontitis.

Clinical and microbiological evaluation of the effectiveness of the Nd:Yap laser for the initial treatment of adult periodontitis. A randomized controlled study

BACKGROUND

Enhancement of the results obtained by scaling and planing is most often sought by using antimicrobial therapies. Laser beams have been shown to be bactericidal and could possibly target pathogens more effectively and with fewer compliance problems than antiseptic solutions.

METHODS

Thirty subjects 20-60 years old presenting periodontal pockets at least 5 mm deep in each quadrant received initial periodontal treatment. The study had a split-mouth design. The control side (SRP) only received scaling and planing, and the test side (SRP+laser) was treated by both SRP and Nd:Yap (yttrium aluminum perovskite doped with neodym) laser. Clinical conditions were evaluated at day 0 and day 90 using the plaque index, gingival index, bleeding on probing, pocket probing depth, and clinical attachment level. Microbial sampling was also performed on days 0 and 90, and the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola was analysed by polymerase chain reaction in a commercial laboratory. Post-operative pain or discomfort was measured by the patient using a linear visual scale. Pearson's chi-squared test was used to compare bacterial presence.

RESULTS

There was no statistically significant difference concerning clinical data between test and control groups at baseline. Both treatments enhanced the clinical situation compared to baseline; however, results were not significantly different between the two groups. T. forsythensis was the organism most numerous in both groups. Though initial treatment diminished the numbers of all the pathogens it did not do so statistically significantly. Differences between test and control groups were very small and bore no significance. Evaluation of the post-operative pain did not reveal any differences between the groups.

CONCLUSIONS

Scaling and root planing was effective in reducing levels of plaque, inflammation, and bleeding upon probing. No additional advantage was achieved by using the Nd:Yap laser.

Neodymium:yttrium aluminum garnet laser irradiation with low pulse energy: a potential tool for the treatment of peri-implant disease

Bacterial contamination may seriously compromise successful implant osteointegration in the clinical practice of dental implantology. Several methods for eliminating bacteria from the infected implants have been proposed, but none of them have been shown to be an effective tool in the treatment of peri-implantitis. In the present study, we investigated the efficacy of pulsed neodymium:yttrium aluminum garnet laser irradiation (Nd:YAG) in achieving bacterial ablation while preserving the surface properties of titanium implants. For this purpose, suspensions of Escherichia coli or Actinobacillus (Haemophilus) actinomycetemcomitans were irradiated with different laser parameters, both streaked on titanium implants, and in broth medium. It was found, by light and atomic force microscopy, that Nd:YAG laser, when used with proper working parameters, was able to bring about a consistent microbial ablation of both aerobic and anaerobic species, without damaging the titanium surface.

Little evidence for the use of diode lasers as an adjunct to non-surgical periodontal therapy

DATA SOURCES

Medline, PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL) and Embase databases.

STUDY SELECTION

Randomised controlled trials (RCTs) using thermal diode lasers as an adjunct to non-surgical conventional periodontal initial therapy conducted in patients ≥18 years old written in English or Dutch were considered.

DATA EXTRACTION AND SYNTHESIS

Study assessment data extraction and quality assessment was carried out independently by two reviewers. The main outcome variables were probing pocket depth (PPD) and clinical attachment loss (CAL), but plaque scores (PS), bleeding scores (BS) and the Gingival Index (GI) were also considered. Meta-analysis was carried out using a random effects model.

RESULTS

Nine studies involving 247 patients were included. Seven studies were of split mouth design and two were parallel group studies. The study designs showed considerable heterogeneity and follow up ranged from six weeks to six months. Meta-analysis found no significant effect on PPD, CAL and PS. There was however a significant effect for GI and BS favouring adjunctive use of the diode laser.

CONCLUSIONS

The collective evidence regarding adjunctive use of the diode laser with SRP indicates that the combined treatment provides an effect comparable to that of SRP alone. With respect to BS the results showed a small but significant effect favouring the diode laser, however, the clinical relevance of this difference remains uncertainStandard . This systematic review questions the adjunctive use of diode laser with traditional mechanical modalities of periodontal therapy in patients with periodontitis. The strength of the recommendation for the adjunctive use of the diode laser is considered to be 'moderate' for changes in PPD and CAL.

Effect of 650-nm low-level laser irradiation on c-Jun, c-Fos, ICAM-1, and CCL2 expression in experimental periodontitis

This study was designed to investigate the effect of 650-nm low-level laser irradiation (LLLI) as an adjunctive treatment of experimental periodontitis. To investigate possible LLLI-mediated anti-inflammatory effects, we utilized an experimental periodontitis (EP) rat model and analyzed c-Jun, c-Fos, ICAM-1, and CCL2 gene expressions on PB leukocytes and in the gingival tissue. Total RNA was isolated from the gingivae and peripheral blood (PB) leukocytes of normal, EP, scaling, and root planing (SRP)-treated EP and LLLI + SRP-treated EP rats, and gene expressions were analyzed by real-time PCR. The productions of c-Jun, c-Fos, ICAM-1, and CCL2 in gingivae were analyzed immunohistochemically. Tartrate-resistant acid phosphatase (TRAP) staining was used to determine osteoclast activity in alveolar bone. The c-Jun and ICAM-1 messenger RNA (mRNA) levels were significantly decreased in the EP rat gingival tissue treated by SRP + LLLI than by SRP, the c-Jun, ICAM-1, and c-Fos mRNA levels on PB leukocytes reduced after LLLI treatment but did not show any significant differences in both groups. There was no significant difference in CCL2 mRNA levels on PB leukocytes and in gingivae between the SRP + LLLI and the SRP groups. The c-Fos mRNA levels in gingivae did not show significant difference in both groups. Immunohistochemistry showed that the CCL2, ICAM-1, c-Jun, and c-Fos productions were significantly reduced in rats of the SRP + LLLI group compared with the only SRP group. LLLI significantly decreased the number of osteoclasts as demonstrated by TRAP staining. The 650-nm LLLI might be a useful treatment modality for periodontitis.

ArF-193 Excimer Laser and Emdogain® in the Treatment of Experimental Periodontitis: An Experimental Study in Rabbits

OBJECTIVE

We aimed to investigate how the progress made on laser technology during the last ten years could overcome this obstacle and allow the use of lasers in periodontology, together with the application of a number of products permitting the regeneration of periodontal tissues.

BACKGROUND DATA

The use of lasers in dentistry remains controversial, in spite of their increasing application in medical practice. The main reason for this discrepancy is the frequent report of damage to surrounding tissues and the dental pulp, due to the energy transfer, from the site of laser impact.

METHODS

Experimental periodontitis was initiated in fifteen rabbits. Animals were divided into five equal groups. In the control group, no therapy was applied. The remaining four groups were treated with curettage or ArF 193 excimer laser, under conditions of strict control of frequency, fluency, and application, without or with the application of a periodontal healing product (Emdogain). Laser was applied by the use of a new, articulated arm for beam delivery. Pocket depth and microscopic analysis were performed three weeks after treatment.

RESULTS

Our results show that all treatment groups decreased pocket depth significantly. ArF193 excimer laser does not produce any histological damage to the dental pulp, and facilitates periodontal regeneration. This result is highly facilitated by the application of Emdogain).

CONCLUSIONS

The use of UV lasers, under a tight control of its energy, may be a valuable tool for the treatment of periodontal diseases, especially combined with the use of healing products. Further study is need to confirm these results.

Photobiomodulation of oral fibroblasts stimulated with periodontal pathogens

Photobiomodulation (PBM) utilises light energy to treat oral disease, periodontitis. However, there remains inconsistency in the reporting of treatment parameters and a lack of knowledge as to how PBM elicits its molecular effects in vitro. Therefore, this study aimed to establish the potential immunomodulatory effects of blue and near infra-red light irradiation on gingival fibroblasts (GFs), a key cell involved in the pathogenesis of periodontitis. GFs were seeded in 96-well plates in media + / - Escherichia coli lipopolysaccharide (LPS 1 μg/ml), or heat-killed Fusobacterium nucleatum (F. nucleatum, 100:1MOI) or Porphyromonas gingivalis (P. gingivalis, 500:1MOI). Cultures were incubated overnight and subsequently irradiated using a bespoke radiometrically calibrated LED array (400-830 nm, irradiance: 24 mW/cm² dose: 5.76 J/cm²). Effects of PBM on mitochondrial activity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and adenosine triphosphate (ATP) assays, total reactive oxygen species production (ROS assay) and pro-inflammatory/cytokine response (interleukin-8 (IL-8) and tumour growth factor-β1 (TGFβ1)) were assessed 24 h post-irradiation. Data were analysed using one-way ANOVA followed by the Tukey test. Irradiation of untreated (no inflammatory stimulus) cultures at 400 nm induced 15%, 27% and 13% increases in MTT, ROS and IL-8 levels, respectively (p < 0.05). Exposure with 450 nm light following application of P. gingivalis, F. nucleatum or LPS induced significant decreases in TGFβ1 secretion relative to their bacterially stimulated controls (p < 0.001). Following stimulation with P. gingivalis, 400 nm irradiation induced 14% increases in MTT, respectively, relative to bacteria-stimulated controls (p < 0.05). These findings could identify important irradiation parameters to enable management of the hyper-inflammatory response characteristic of periodontitis.

Effect of photobiomodulation with different wavelengths on periodontal repair in non-hyperglycemic and hyperglycemic rats

BACKGROUND

Hyperglycemic conditions is associated with more severe periodontitis and poorer outcomes after nonsurgical periodontal treatment (NPT). Then, these patients are candidates for adjunctive therapy associated with NPT. This study evaluates the effect of photobiomodulation (PBMT) at different wavelengths on periodontal repair in non-hyperglycemic/hyperglycemic animals.

MATERIALS AND METHODS

Sixty-four rats were submitted to induction of periodontitis by ligatures. Hyperglycemia was induced in half of these animals, whereas the other half remained non-hyperglycemic. The animals were subdivided into 4 groups according to the PBMT protocol applied at the time of ligature removal (n = 8): CTR: Without PBMT; IRL: PBMT with infrared laser (808 nm); RL: PBMT with red laser (660 nm); and RL-IRL: PBMT with red (660 nm) and infrared laser (808 nm). After a period of 7 days, the animals were euthanized. The parameters assessed by microtomography were the bone volume relative to total tissue volume (BV/TV%), distance from the cemento-enamel junction to the top of the bone crest (CEJ-CB), trabecular thickness, space between trabeculae, and number of trabeculae. Additionally, the percentage of inflammatory cells, blood vessels, and connective tissue matrix were assessed by histomorphometric analysis.

RESULTS

PBMT reduced bone loss and increased trabecular density in hyperglycemic animals (p < .05), with RL being more effective in reducing linear bone loss (CEJ-CB), whereas RL-IRL was more effective in maintaining BV/TV%. PBMT reduced blood vessels and increased the connective tissue component in hyperglycemic animals (p < .05). RL-IRL reduced inflammatory cells regardless of the systemic condition of the animal (p < .05).

CONCLUSION

PBMT (RL, RL-IRL) improves the repair of periodontal tissues in hyperglycemic animals.

Diode laser offers minimal benefit for periodontal therapy

Current evidence indicates that use of diode lasers in the treatment of periodontitis--either as a monotherapy or adjunctive to traditional therapy--offers minimal benefit. Further, subgingival application of the diode laser during nonsurgical periodontal therapy can result in undesired outcomes, even when using manufacturer-recommended parameters.

Effectiveness of Diode (810 nm) Laser in Periodontal Parameters and Reduction of Subgingival Bacterial Load in Periodontitis Patients

AIM

This split-mouth randomized trial (RCT) aimed to assess the effect of diode laser on the clinical parameters in patients with periodontitis, compare the results with scaling and root planing (SRP) alone, and assess the implications of diode laser (DL) on plaque bacteria.

MATERIALS AND METHODS

Seventeen periodontitis patients were randomly assigned into two equal groups based on the therapy delivered. Group I (control site) received just SRP at baseline, while group II (test site) received both SRP and DL irradiation. For both groups, the clinical periodontal parameters probing pocket depth (PPD), and clinical attachment level (CAL) were measured at baseline, 30 days, and 90 days. Microbiological amount was also measured at baseline, 30, and 90 days after periodontal treatment. The amounts of Aggregatibacter actinomycetemcomitans (A.a), Prevotella intermedia (Pr. intermedia), and Porphyromonas gingivalis (P. gingivalis) were determined using real-time PCR probing with specific bacterial primers.

RESULTS

In both groups, PPD and CAL showed statistically significant reductions at different time intervals (p < 0.05). No significant difference were observed in CAL values after 1 and 3 months in both test and control groups (p > 0.05). The mean values of the concentration of A.a, Pr. intermedia and P. gingivalis were lower in the case group as compared to the control group and the difference was statistically significant after 1 month (*p = 0.001).

CLINICAL SIGNIFICANCE

According to this study, non-invasive laser treatment has the potential to improve clinical outcomes by lowering the quantity of A.a, Pr. intermedia and P. gingivalis.

CONCLUSION

In both groups, a considerable decrease in the periodontal pathogens A.a, Pr. intermedia and P. gingivalis were discovered; however, the intergroup comparison was insignificant in relation to PD and CAL. The adjunctive treatment with diode laser showed better efficacy in ensuring a better periodontal treatment than SRP alone. How to cite this article: Abdullah LA, Hashim N, Rehman MM, et al. Effectiveness of Diode (810 nm) Laser in Periodontal Parameters and Reduction of Subgingival Bacterial Load in Periodontitis Patients. J Contemp Dent Pract 2023;24(12):1008-1015.

Impact of Laser Therapy on Periodontal and Peri-Implant Diseases

Objective: In the last few decades, lasers in dentistry have encompassed all branches in dentistry, with more focus in periodontology. In recent years, the use of lasers against periodontitis and peri-implantitis has undergone a decisive development that has involved various operational areas. The broadest applications were probably found in the clinical approach to soft tissues. Methods: Laser therapy is a novel technique that may provide further beneficial effects to conventional periodontal and peri-implant therapies. However, clinical evidence for the improvement of periodontal wound healing and tissue regeneration through laser treatment is still limited. Results: This review is aimed at assessing the advantages and disadvantages of the use of lasers in dental procedures and pathologies, focusing more on protocols for the management of periodontal and peri-implant diseases. Conclusions: The adjuvant action of laser therapy, in addition to conventional therapies for the management of periodontal and peri-implant disease, could induce benefits, but further investigation would be necessary to standardize better the protocols applied and to understand the actual tissue response to laser therapy.

Evaluation of two low-level laser techniques as an adjunct to basic periodontal therapy: a randomized clinical trial

To assess and compare two techniques of low-level laser application-transgingival (TLLLT) and intrasulcular (ILLLT)-used in photobiomodulation as an adjunct to basic periodontal therapy (BPT) in patients with periodontitis. A randomized, split-mouth, double-blind clinical trial was conducted, selecting three diseased periodontal sites from different quadrants in each patient. These sites were assigned to one of three treatment groups: SRP (control), SRP + TLLLT (test 1), and SRP + ILLLT (test 2). Low-level laser therapy in the test groups was applied at 48 h, 7 days, and 14 days after full-mouth SRP. Clinical parameters such as probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were assessed at baseline (T0), 3 months (T1), and 6 months (T2). Standardized periapical radiographs were used to assess radiographic bone density (RBD) 6 months post-treatment. Statistical analyses included repeated measures ANOVA for continuous variables and chi-square tests for categorical variables, with significance set at p < 0.05 and a 95% confidence interval. Significant reductions in PD (p < 0.001) and CAL (p < 0.001) were observed across all groups at 3 and 6 months, with no significant differences between groups. There were also no significant changes in BOP and RBD between groups at the follow-up intervals. Adjunctive photobiomodulation did not provide additional clinical or radiographic benefits over SRP alone, regardless of the laser application technique employed.

[A short-term clinical evaluation of periodontal treatment with an Er:YAG laser for patients with chronic periodontitis: a split-mouth controlled study]

OBJECTIVE

To compare the short-term clinical effects following non-surgical periodontal treatment with Er:YAG laser or with combination of ultrasonic subgingival scaling and root planing with hand instrument (SRP) for patients with chronic periodontitis.

METHODS

In the study, 17 patients with chronic periodontitis were randomly treated in a split-mouth design with Er:YAG laser (test group) or a combination of ultrasonic subgingival scaling and root planing with hand instrument (control group). The degree of discomfort experienced during the treatment was graded by the patient using visual analogue scale (VAS) immediately after the completion of test and control treatment procedures. The following clinical parameters were recorded by a calibrated and blinded examiner: plaque index (PLI), bleeding index (BI), probing depth (PD) and attachment loss (AL).

RESULTS

The mean VAS score of Er:YAG laser treatment [3 (2, 4.5)] was significantly lower than that of control treatment [5 (4, 6), P=0.013]. Both the groups showed significant reduction of PLI, PD, AL and BI values 2 months and 4 months after treatment. For sites with PD≥4 mm at baseline, the sites treated with Er:YAG laser demonstrated mean PD change from (5.6±1.1) mm to (3.6±1.1) mm and to (3.4±1.0) mm at the end of 2 months and 4 months respectively and demonstrated mean AL change from (5.1±1.5) mm to (3.9±1.6) mm and to (3.8±1.7) mm at the end of 2 months and 4 months respectively, meanwhile the BI value showed significant decrease, P=0.000; the sites treated with conventional SRP demonstrated mean PD change from (5.6±1.1) mm to (3.8±1.1) mm and (3.5± 1.0) mm at the end of 2 months and 4 months respectively and demonstrated mean AL change from (4.8±1.6) mm to (3.8±1.6) mm and (3.6±1.8) mm at the end of 2 months and 4 months respectively, and the BI value also showed significant improvement. No statistical difference for all clinical parameters were found between the two treatment groups.

CONCLUSION

The present results indicate that non-surgical periodontal therapy with Er:YAG laser is safe and effective, and Er:YAG laser therapy could be used for patients who was sensitive to pain.

Low-level laser therapy alleviates periodontal age-related inflammation in diabetic mice via the GLUT1/mTOR pathway

Diabetes mellitus (DM) is a chronic age-related disease that was recently found as a secondary aging pattern regulated by the senescence associated secretory phenotype (SASP). The purpose of this study is to detect the potential efficacy and the specific mechanisms of low-level laser therapy (LLLT) healing of age-related inflammation (known as inflammaging) in diabetic periodontitis. Diabetic periodontitis (DP) mice were established by intraperitoneal streptozotocin (STZ) injection and oral P. gingivalis inoculation. Low-level laser irradiation (810 nm, 0.1 W, 398 mW/cm2, 4 J/cm2, 10 s) was applied locally around the periodontal lesions every 3 days for 2 consecutive weeks. Micro-CT and hematoxylin-eosin (HE) stain was analyzed for periodontal soft tissue and alveolar bone. Western blots, immunohistochemistry, and immunofluorescence staining were used to evaluate the protein expression changes on SASP and GLUT1/mTOR pathway. The expression of aging-related factors and SASP including tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 were reduced in periodontal tissue of diabetic mice. The inhibitory effect of LLLT on GLUT1/mTOR pathway was observed by detecting the related factors mTOR, p-mTOR, GLUT1, and PKM2. COX, an intracytoplasmic photoreceptor, is a key component of the anti-inflammatory effects of LLLT. After LLLT treatment a significant increase in COX was observed in macrophages in the periodontal lesion. Our findings suggest that LLLT may regulate chronic low-grade inflammation by modulating the GLUT1/mTOR senescence-related pathway, thereby offering a potential treatment for diabetic periodontal diseases.