Comparison of clinical parameters, microbiological effects and calprotectin counts in gingival crevicular fluid between Er: YAG laser and conventional periodontal therapies: A split-mouth, single-blinded, randomized controlled trial

SIRT6 alleviates senescence induced by Porphyromonas gingivalis in human gingival fibroblasts

OBJECTIVE

Bidirectional influences between senescence and inflammation are newly discovered. This study aimed to clarify the roles and mechanism of Porphyromonas gingivalis (P. gingivalis) in exacerbating senescence in human gingival fibroblasts (HGFs).

DESIGN

Subgingival plaque and gingivae were collected from twenty-four periodontitis patients and eighteen periodontally healthy subjects. Quantities of P. gingivalis in subgingival plaque were explored using real-time PCR and the expressions of p53, p21 and SIRT6 in gingivae were detected by IHC. Moreover, senescence in HGFs was induced by P. gingivalis lipopolysaccharide (LPS) and the expressions of senescence-related β-galactosidase (SA-β-gal), p53, p21 and senescence-associated secretory phenotype (IL-6 and IL-8) with or without treatment by SIRT6 activator UBCS039 were explored by IHC, western blot and ELISA, respectively. In addition, the levels of SIRT6, Nrf2, HO-1 and reactive oxygen species (ROS) were examined by western blot and flow cytometry.

RESULTS

Quantities of P. gingivalis in subgingival plaque and semi-quantitative scores of p53 and p21 in gingivae of periodontitis patients were increased compared with healthy controls (p < 0.05), while SIRT6 score in periodontitis patients was decreased (p < 0.001). Quantities of P. gingivalis were positively correlated with p53 and p21 scores (0.6 < r < 0.9, p < 0.01), and negatively correlated with SIRT6 score (-0.9 < r<-0.6, p < 0.01). Moreover, P. gingivalis LPS increased the levels of SA-β-gal, p53, p21, IL-6, IL-8 and ROS and decreased the levels of SIRT6, Nrf2 and HO-1 in HGFs, which was rescued by UBCS039 (p < 0.05).

CONCLUSIONS

P. gingivalis LPS could induce senescence of HGFs, which could be reversed by SIRT6 via Nrf2-HO-1 signaling pathway.

Effect of Er: YAG Laser Irradiation on Bone Metabolism-Related Factors Using Cultured Human Osteoblasts

Introduction: A variety of laser treatments have been applied in numerous medical fields. In dentistry, laser treatments are used for caries, root canals, and periodontal disease, as well as surgical resection. Numerous reports have recently been published on the use of lasers for bone regeneration. If laser irradiation is found to promote the activation of bone metabolism, it might also be effective for periodontal treatment, peri-implantitis, and bone regeneration. Therefore, the present in vitro study aimed to elucidate the mechanisms underlying the effects of erbium-doped yttrium aluminum garnet (Er: YAG) laser irradiation on the bone using osteoblast-like cells. Methods: Osteoblast-like Saos 2 cells (5.0×104 cells) were seeded in 24-well plates. 24 hours after being seeded, the cells were subjected to 0.3 W, 0.6 W, and 2.0 W Er: YAG laser irradiation and then allowed to recover for 48 hours. The expression levels of bone metabolism-related factors alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteoprotegerin (OPG) were then evaluated using reverse transcription-quantitative polymerase chain reaction and western blot analyses. Results: Saos 2 cells subjected to Er: YAG laser irradiation at 0.3 W, 0.6 W, and 2.0 W showed normal growth. When the Er: YAG laser irradiation and control groups were compared after 48 hours, increases were observed in ALP, BSP, and OPG gene and protein expression in the 2.0 W group. Similar results were obtained in the western blot analysis. Conclusion: These findings suggest that the Er: YAG laser irradiation of osteoblast-like cells is effective for activating bone metabolism factors.

Effects of Laser Therapy on Periodontal Status in Adult Patients Undergoing Orthodontic Treatment

Orthodontic treatment with fixed devices should only be indicated in case of a stable, non-active periodontal disease status. Throughout orthodontic treatment, a careful assessment of the periodontal status is advised. Due to its anti-inflammatory and antimicrobial effects, laser therapy is frequently used as an adjunct to classic periodontal therapy. The aim of this study was to evaluate the advantages and limitations of the use of laser therapy on periodontal status during orthodontic treatment. Throughout the 9 months during which this placebo-controlled, single-blind clinical trial was conducted, 32 patients were included in the study, divided into two groups: microscope “+” (patients who observed the bacteria within the dental plaque-sample examination on the screen of a dark-field microscope in real time) and microscope “−” (patients who did not see the oral pathogens using a dark-field microscope). For all patients, using the split-mouth study design, laser therapy was applied to one hemiarch (HL), whereas the other hemiarch received treatment without active light (HC). After one month, by analyzing the main indicators of periodontal health status, we found that the plaque index (PI) and bleeding on probing (BOP) values were significantly decreased after receiving treatment (for PI: HL-p = 0.0005, HC-p = 0.0297; for BOP: HL-p = 0.0121, HC-p = 0.0236), whereas the probing-depth (PD) values remained almost the same as before treatment (HL-p = 1.5143; HC-p = 1.4762). Conclusions: The use of the dark-field microscope proved to be beneficial in sensitizing patients to the presence of bacteria in the oral cavity and motivated them to strictly follow the rules of oral hygiene. Laser treatment can be a valuable aid in periodontal therapy, but only in adjunction with mechanical therapy.

Probing depth reduction of laser application in periodontal therapy: a network meta-analysis

The aim was to systematically evaluate the probing depth (PD) reduction of lasers in scaling and root planing (SRP) of chronic periodontitis by network meta-analysis (NMA). Randomized controlled clinical trials (RCTs) were searched through electronic-search and hand-search up to January 2020. Standard mean different (SMD) and 95% confidence interval (CI) were counted for PD reduction. The random-effects NMA were performed using mvmeta routine in STATA software (version 13). This NMA analysed seven periodontal treatments through 37 RCTs. No inconsistency was detected. Compared with mechanical SRP, significant differences were in favour of diode laser (DL) as adjunct at 3 months (SMD = 0.61; 95% CI range: 0.27-0.96) and Nd:YAG as adjunct (SMD = 0.29; 95% CI range: 0.03-0.55), Er,Cr:YSGG as monotherapy (SMD = 0.37; 95% CI range: 0.04-0.71) and Er,Cr:YSGG as adjunct (SMD = 0.53; 95% CI range: 0.23-0.84) at 6 months after treatment. Compared with Er:YAG as monotherapy, significant differences were in favour of DL as adjunct at 6 months (SMD = 0.51; 95% CI range: 0.07-0.95) after treatment. In terms of PD reduction at 3-month follow-up, the ranking result from best to worst was Nd:YAG as adjunct, DL as adjunct, Er:YAG as adjunct, Er,Cr:YSGG as monotherapy, Er:YAG as monotherapy and mechanical SRP. In terms of PD reduction at 6-month follow-up, the ranking result was DL as adjunct, Nd:YAG as adjunct, Er:YAG as adjunct, Er,Cr:YSGG as adjunct, Er:YAG as monotherapy, Er,Cr:YSGG as monotherapy and mechanical SRP. Laser-assisted periodontal treatment has better PD reduction.

Erbium lasers in non-surgical periodontal therapy: an umbrella review and evidence gap map analysis

The literature on the efficacy of erbium lasers for nonsurgical periodontal therapy is inconsistent. The objective of the umbrella review was to collate the information available in the systematic reviews to provide a comprehensive synthesis of clinical and patient reported outcomes following the use of erbium lasers for non-surgical periodontal therapy. An electronic database search was carried out, and systematic reviews/meta-analyses which assessed the efficacy of erbium lasers as monotherapy or as an adjunct to scaling and root planing were included. The methodological quality and reporting quality of the included studies were assessed. 15 Systematic reviews/meta-analyses were obtained after title, abstract, and full text search. The meta-analyses data revealed a clinical attachment level gain, reduction in probing pocket depth at 1 and 3-month follow-up, and no additional benefit at ≥ 6-month follow-up in the erbium laser group. The evidence gap map revealed lack of clinical outcome data at > 6-month follow-up and dearth in studies assessing patient reported outcome measures and adverse events. Erbium lasers may provide short-term clinical benefits, and further studies with standardized laser parameters evaluating long-term follow-up, patient-reported outcome measures, and adverse events are needed.

Treatment effects and periodontal status of chronic periodontitis after routine Er:YAG laser-assisted therapy

BACKGROUND

Routine preclinical interventions for patients with chronic periodontitis such as supragingival cleaning and subgingival curettage, establishing a balanced occlusal relationship, and irrigation with 3% hydrogen peroxide can relieve the symptoms to some extent. However, there is room for improvement in the overall effect. For example, Er:YAG lasers can quickly increase the temperature of the irradiated tissue, effectively eliminate dental plaque and calculus, reduce periodontal pockets, adjust periodontal microecology, and reduce the gingival sulcus. The content of factors in the liquid, and then achieve the purpose of treatment.

AIM

The aim was evaluate the effect of Er:YAG laser-assisted routine therapy on the periodontal status in chronic periodontitis.

METHODS

Between October 2018 and January 2020, 106 patients with chronic periodontitis in our hospital were randomly assigned to either the study or control group, with 53 patients in each group. The control group underwent routine therapy, and the study group underwent Er:YAG laser therapy in addition to routine therapy. We evaluated the treatment outcome in both groups. Periodontal status was determined by clinical attachment loss (CAL), gingival index (GI), periodontal probing depth (PD), dental plaque index (PLI), and sulcular bleeding index (SBI), inflammatory factors in the gingival crevicular fluid, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-8], and colony forming units (CFUs).

RESULTS

Total effectiveness in the study group (94.34%) was higher than that in the control group (79.25%, P < 0.05). The clinical parameters in the study group (PD, 5.28 ± 1.08 mm; CAL, 4.81 ± 0.79 mm; SBI, 3.37 ± 0.59; GI, 1.38 ± 0.40; PLI, 2.05 ± 0.65) were not significantly different from those in the control group (PD, 5.51 ± 1.14 mm; CAL, 5.09 ± 0.83 mm; SBI, 3.51 ± 0.62; GI, (1.41 ± 0.37; PLI, 1.98 ± 0.70) before treatment (P > 0.05). However, after treatment, the parameters in the study group (PD, 2.97 ± 0.38 mm; CAL, 2.71 ± 0.64 mm; SBI, 2.07 ± 0.32; GI, 0.51 ± 0.11; PLI, 1.29 ± 0.34) were lower than those in the control group (PD, 3.71 ± 0.42 mm; CAL, 3.60 ± 0.71 mm; SBI, 2.80 ± 0.44; GI, 0.78 ± 0.23; PLI, 1.70 ± 0.51) (P < 0.05). Differences in crevicular TNF-α, IL-6, and IL-8 levels in the study (TNF-α, 7.82 ± 3.43 ng/mL; IL-6, 11.67 ± 2.59 ng/mL; IL-8, 12.12 ± 3.19 pg/mL) and control groups (TNF-α, 9.06 ± 3.89 ng/ml, IL-6, 12.13 ± 2.97 ng/mL, IL-8, 10.99 ± 3.30 pg/mL) before therapy (P > 0.05) were not significant. Following treatment, the parameters were significantly lower in the study group (TNF-α, 2.04 ± 0.89 ng/mL; IL-6, 4.60 ± 1.26 ng/mL; IL-8, 3.15 ± 1.08 pg/mL) than in the control group (TNF-α, 3.11 ± 1.07 ng/mL; IL-6, 6.25 ± 1.41 ng/mL; IL-8, 4.64 ± 1.23 pg/mL, P < 0.05). The difference in the CFU of the study group [(367.91 ± 74.32) × 10⁴/mL and control group (371.09 ± 80.25) × 10⁴/mL] before therapy was not significant (P > 0.05). The CFU decreased in both groups following therapy, however, the CFU values were lower in the study group [(36.09 ± 15.26) × 10⁴/mL] than in the control group [(45.89 ± 18.08) ×10⁴/mL] (P < 0.05).

CONCLUSION

Combining Er:YAG lasers with routine measures significantly improved the overall periodontal therapy outcomes by improving periodontal status and reducing oral levels of inflammatory factors and CFUs.

Efficacy of laser monotherapy or non-surgical mechanical instrumentation in the management of untreated periodontitis patients. A systematic review and meta-analysis

OBJECTIVE

To evaluate and compare the effects of laser monotherapy with non-surgical mechanical instrumentation alone in untreated periodontitis patients.

MATERIALS AND METHODS

A focused question was formulated based on the Population, Intervention, Comparison, Outcome, and Study design criteria (PICOS): in patients with untreated periodontitis, does laser mono-therapy provide adjunctive effects on pocket probing depth (PPD) changes compared with non-surgical instrumentation alone? Both randomized controlled clinical trials (RCTs) and controlled clinical trials (CCTs) were included. The results of the meta-analyses are expressed as weighted mean differences (WMD) and reported according to the PRISMA guidelines.

RESULTS

The search yielded 1268 records, out of which 8 articles could be included. With respect to PPD changes, a meta-analysis including 5 articles (n = 148) failed to identify statistically significant differences in favor of laser monotherapy for PPD change (WMD = 0.14 mm; 95% CI: - 0.04/0.32; z = 1.51; p = 0.132) nor for clinical attachment level (CAL) (WMD = 0.04 mm; 95% CI: - 0.35/0.42; z = 0.19; p = 0.850). Data on cost-effectiveness are lacking. One study reported patient-related outcome measures (PROMS).

CONCLUSIONS

In untreated periodontitis patients, laser monotherapy does not yield superior clinical benefits compared with non-surgical mechanical instrumentation alone.

CLINICAL RELEVANCE

In untreated periodontitis patients, mechanical instrumentation with hand and/or ultrasonic instruments remains the standard of care.

Treating periodontitis-a systematic review and meta-analysis comparing ultrasonic and manual subgingival scaling at different probing pocket depths

BACKGROUND

Mechanical plaque removal has been commonly accepted to be the basis for periodontal treatment. This study aims to compare the effectiveness of ultrasonic and manual subgingival scaling at different initial probing pocket depths (PPD) in periodontal treatment.

METHODS

English-language databases (PubMed, Cochrane Central Register of Controlled Trials, EMBASE, Medline, and ClinicalTrials.gov, by January, 2019) were searched. Weighted mean differences in primary outcomes, PPD and clinical attachment loss (CAL) reduction, were estimated by random effects model. Secondary outcomes, bleeding on probing (BOP), gingival recession (GR), and post-scaling residual dental calculus, were analyzed by comparing the results of each study. The quality of RCTs was appraised with the Cochrane Collaboration risk of bias tool. The GRADE approach was used to assess quality of evidence.

RESULTS

Ten randomized controlled trials were included out of 1434 identified. Initial PPD and follow-up periods formed subgroups. For 3-months follow-up: (1) too few shallow initial pocket studies available to draw a conclusion; (2) the heterogeneity of medium depth studies was so high that could not be merged to draw a conclusion; (3) deep pocket studies showed no statistical differences in PPD and CAL reduction between ultrasonic and manual groups. For 6-months follow-up: (1) too few shallow initial PPD studies to draw a conclusion; (2) at medium pocket depth, PPD reduction showed manual subgingival scaling better than ultrasound. No statistical differences were observed in CAL reduction between the two approaches; (3) for deep initial PPD studies, both PPD and CAL reduction showed manual subgingival scaling better. GR results indicated no statistical differences at medium and deep initial pocket studies between the two methods. BOP results showed more reduction at deep pocket depths with manual subgingival scaling. No conclusion could be drawn about residual dental calculus.

CONCLUSION

When initial PPD was 4-6 mm, PPD reduction proved manual subgingival scaling was superior, but CAL results showed no statistical differences between the two means. When initial PPD was ≥6 mm, PPD and CAL reductions suggested that manual subgingival scaling was superior.

Professional tooth cleaning prior to non-surgical periodontal therapy: A randomized clinical trial

BACKGROUND

This study was aimed to investigate if professional oral prophylaxis before scaling and root planing (SRP) has an effect on the outcome of non-surgical periodontal treatment in patients with chronic periodontitis.

METHODS

Fifty-two individuals with chronic periodontitis receiving non-surgical periodontal therapy by SRP with (test) and without (control) two appointments of professional tooth cleaning but with motivation and instruction were monitored for clinical variables, four selected microorganisms and two biomarkers at baseline, before SRP as well as 3 and 6 months after SRP. Statistical analysis included non-parametric tests for intra- and intergroup comparisons.

RESULTS

Probing depth (PD), attachment level, bleeding on probing (BOP), and interproximal plaque index (API) were significantly improved in both groups 3 and 6 months after SRP. PD, BOP, API, and the number of sites with PD ≥5 mm were significantly lower in the test group than in the control group at the appointment immediately before SRP. Tannerella forsythia was significantly reduced in both groups at 3 and 6 months, Porphyromonas gingivalis only in the test group. Interleukin-1β was significantly reduced in the control group 3 and 6 months after SRP, matrix metalloproteinase-8 level decreased in the test group 3 months after SRP. There was no significant difference of any clinical and non-clinical variable between both groups at 3 and 6 months after SRP.

CONCLUSIONS

Professional tooth cleaning before the SRP does not improve the clinical results of the SRP. It has no obvious long-lasting effects on major periodontopathogens in the subgingival biofilm as well as on biomarkers in the gingival crevicular fluid after SRP.