Long-term effects of a single application of a water-cooled pulsed Nd:YAG laser in supplement to scaling and root planing in patients with periodontal inflammation

The effectiveness of scaling and root planing with combined application of air polishing and Nd:YAG laser in periodontal pockets of stage III grade C periodontitis patients: a single-blinded randomized clinical trial

OBJECTIVES

Evaluating the efficiency of combined air polishing and Nd:YAG laser application in addition to scaling and root planning (SRP) in treatment of periodontal pockets of stage III grade C periodontitis patients was the aim of this clinical trial.

MATERIALS AND METHODS

Twenty-four systemically healthy, stage III grade C periodontitis patients were recruited for this clinical trial. In this split-mouth study, the quadrants were randomly allocated to either SRP with combined air polishing (erythritol/chlorhexidine powder) and Nd:YAG laser (2 W, 200 mJ/pulse, 10 Hz) therapy (test group) or SRP alone (control group). A masked examiner recorded clinical parameters such as plaque index (PI), gingival index (GI), bleeding on probing (%) (BOP %), probing depth (PD), and clinical attachment level (CAL) on periodontal charts at baseline, 1 month and 3 months after treatment.

RESULTS

The clinical parameters had significantly reduced 1 and 3 months after treatment compared to baseline for both study groups (p < 0.05). Considering PI, GI, and BOP (%) parameters, there were no significant differences between the study groups at any time points (p > 0.05). While PD and CAL reductions were similar in study groups for moderately deep pockets (5 to 6 mm) (p > 0.05), PD and CAL reductions were significantly greater in test group compared to control group for deep pockets (PD ≥ 7 mm) (p < 0.05).

CONCLUSIONS

The present clinical trial demonstrated that SRP with combined application of air polishing and Nd:YAG laser may be advantageous in sites where mechanical debridement alone cannot access, such as deep pockets in the short term. Long-term, well-designed future studies including clinical, biochemical, and microbiological analyses are needed to determine the effectiveness of this procedure.

CLINICAL RELEVANCE

SRP with combined application of air polishing and Nd:YAG laser provided more reductions in probing depth and clinical attachment level parameters in deep pockets compared to SRP alone.

Efficacy of Nd:YAG laser-assisted periodontal therapy for the management of periodontitis: A double-blind split-mouth randomized controlled clinical trial

BACKGROUND

This study aimed to explore the efficacy of Nd:YAG laser-assisted periodontal therapy for management of patients with stage II-IV periodontitis.

METHODS

Patients who presented with residual periodontal pockets were enrolled. After non-surgical periodontal therapy (NSPT), test sites received Nd:YAG laser (first entrance to pocket: 3 W, 100 μs, 20 Hz; second entrance: 4 W, 600 μs, 20 Hz) and control sites received placebo (laser off). Periodontal probing depth (PPD), clinical attachment level (CAL), gingival recession (GR), bleeding on probing (BOP), and plaque index (PI) were recorded at baseline and 1, 2, 3, 4 and 6-month visits.

RESULTS

Twenty patients completed the 6-month period. Significant reductions in PPD, CAL, BOP, and PI values and a significant increase in GR at all follow-up visits compared to the baseline (all P < 0.001) were revealed in both groups. Test sites showed significantly greater improvement in PPD (P = 0.0002) and greater increase in GR (P < 0.0001) compared to the control sites at 6-month visit. There was no difference between two groups regarding CAL gain through the study period (P = 0.23).

CONCLUSION

NSPT+Nd:YAG laser with the current protocol results in greater PPD reduction compared to NSPT alone. However, this reduction is likely because of greater GR rather than attachment gain. Therefore, the adjunction of Nd:YAG laser (with the current setting) to the NSPT for the treatment of residual periodontal pockets did not ameliorate the clinical outcomes (ClinicalTrials.gov ID: NCT03365167).

Rare earth smart nanomaterials for bone tissue engineering and implantology: Advances, challenges, and prospects

Bone grafts or prosthetic implant designing for clinical application is challenging due to the complexity of integrated physiological processes. The revolutionary advances of nanotechnology in the biomaterial field expedite and endorse the current unresolved complexity in functional bone graft and implant design. Rare earth (RE) materials are emerging biomaterials in tissue engineering due to their unique biocompatibility, fluorescence upconversion, antimicrobial, antioxidants, and anti-inflammatory properties. Researchers have developed various RE smart nano-biomaterials for bone tissue engineering and implantology applications in the past two decades. Furthermore, researchers have explored the molecular mechanisms of RE material-mediated tissue regeneration. Recent advances in biomedical applications of micro or nano-scale RE materials have provided a foundation for developing novel, cost-effective bone tissue engineering strategies. This review attempted to provide an overview of RE nanomaterials' technological innovations in bone tissue engineering and implantology and summarized the osteogenic, angiogenic, immunomodulatory, antioxidant, in vivo bone tissue imaging, and antimicrobial properties of various RE nanomaterials, as well as the molecular mechanisms involved in these biological events. Further, we extend to discuss the challenges and prospects of RE smart nano-biomaterials in the field of bone tissue engineering and implantology.

Comparative Evaluation of the Effects of Antimicrobial Photodynamic Therapy With an LED and a Laser on the Proliferation of Human Gingival Fibroblasts on the Root Surface: An In Vitro Study

Introduction: This study aimed to compare the effects of root biomodification by citric acid and antimicrobial photodynamic therapy (aPDT) with LED and laser on the proliferation of human gingival fibroblasts (HGFs). Methods: This in vitro experimental study evaluated 60 single-rooted teeth extracted due to periodontal disease. The teeth underwent scaling and root planing (SRP), and then 5 × 5 mm blocks were prepared from the cervical area of the teeth 1 mm apical to the cementoenamel junction. The blocks were divided into 4 groups (n=15 blocks): SRP alone (control), SRP + citric acid, SRP + toluidine blue (TBO) + LED light, and SRP + TBO + laser. HGFs were seeded on the surface of the samples, and the methyl thiazolyl tetrazolium (MTT) assay was performed after 24, 48 and 72 hours. Group comparisons were performed using repeated measures ANOVA, while pairwise comparisons of the time points were performed by an LSD test. Results: Cell proliferation was higher in all experimental groups at 48 and 72 hours, compared with 24 hours (P < 0.05). Cell proliferation was significantly different in the citric acid group at 24 hours (P = 0.016) and 48 hours (P = 0.015), compared with other groups. However, cell proliferation was not significantly different in the aPDT group with LED Photosan and a diode laser at 24 and 48 hours (P > 0.05). Conclusion: aPDT and citric acid can enhance the proliferation of HGFs on dentin blocks. Further studies can pave the way for their future use in the clinical setting.

Adjunctive laser or antimicrobial photodynamic therapy to non-surgical mechanical instrumentation in patients with untreated periodontitis: A systematic review and meta-analysis

AIM

To compare the adjunctive effects of lasers or antimicrobial photodynamic therapy (aPDT) to non-surgical mechanical instrumentation alone in untreated periodontitis patients.

MATERIALS AND METHODS

Two focused questions were addressed using the Population, Intervention, Comparison and Outcome criteria as follows: in patients with untreated periodontitis, (a) does laser application provide adjunctive effects on probing pocket depth (PPD) changes compared with non-surgical instrumentation alone? and (b) does application of aPDT provide adjunctive effects on PPD changes compared with non-surgical instrumentation alone? Both randomized controlled clinical trials (RCTs) and controlled clinical trials (CCTs) were included. Results of the meta-analysis are expressed as weighted mean differences (WMD) and reported according to the PRISMA guidelines.

RESULTS

Out of 1,202 records, 10 articles for adjunctive laser and 8 for adjunctive aPDT were included. With respect to PPD changes, 1 meta-analysis including 2 articles (total n = 42; split-mouth design) failed to identify a statistically significant difference (WMD = 0.35 mm; 95%CI: -0.04/0.73; p = .08) in favour of adjunctive aPDT (wavelength range 650-700 nm). In terms of adjunctive laser application, a high variability of clinical outcomes at 6 months was noted. Two articles included patient-reported outcomes and 10 reported on the presence/absence of harms/adverse effects.

CONCLUSIONS

Available evidence on adjunctive therapy with lasers and aPDT is limited by (a) the low number of controlled studies and (b) the heterogeneity of study designs. Patient-reported benefits remain to be demonstrated.

Orthodontic Treatment of Periodontally Compromised Teeth After Laser Periodontal Therapy: A Case Report

Objective: To assess stability of laser periodontal therapy (LPT) results after orthodontic tooth movement. Background: Periodontitis and malocclusion each exhibit high global prevalence. Thus, dentists inevitably face increasing demand for orthodontic treatment in patients with reduced periodontal support. Many of these patients benefit from orthodontic treatment, provided that periodontal inflammation is controlled. Materials and methods: We present a case demonstrating successful orthodontic treatment of periodontally compromised teeth after LPT. A patient with severe attachment and alveolar bone loss received orthodontic treatment 13 months after neodymium-doped: yttrium aluminum garnet LPT (1064 nm). We utilized three laser parameter sets for various purposes during the procedure-ablation of the periodontal pocket epithelium (2.8 W, 20 Hz, 100 μs), clot stabilization (2.8 W, 20 Hz, 550 μs), and photobiomodulation (2.8 W, 20 Hz, 100 μs, noncontact). Results: Treatment resulted in improved radiographic bone levels, clinical parameters consistent with periodontal health, and favorable occlusal relationships. Conclusions: In the presented case, we successfully treated a patient presenting with malocclusion and reduced periodontal support while avoiding the risk and morbidity of conventional periodontal surgery. Controlled clinical research to establish the predictability of the described approach appears warranted.

Treatment with Nd:YAG Laser Irradiation Combined with Sodium Hypochlorite or Hydrogen Peroxide Irrigation on Periodontal Pathogens: An In Vitro Study

Objective: The purpose of this study was to evaluate the effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser with low concentrations of hydrogen peroxide (H₂O₂) or sodium hypochlorite (NaOCl) on viability of oral bacteria. Materials and methods: Bacterial species Streptococcus gordonii, Porphyromonas gingivalis, and Fusobacterium nucleatum were grown in an anaerobic chamber at 37°C. Samples were irradiated with the Nd:YAG laser (1064 nm, 300 μm Varian tip) using parameters: 150 mJ, 20 Hz, 3 W, 50 sec, and 100 μs short pulse duration in contact mode. Treatment groups included (1) control, (2) Nd:YAG, (3) 0.5% H₂O₂, (4) Nd:YAG and 0.5% H₂O₂, (5) 0.5% NaOCl, and (6) Nd:YAG with 0.5% NaOCl. Viable colonies were counted, calculated into colony forming unit/mL, and converted into log form for statistical analysis using a two-tailed paired t-test. Results: The combined treatment with the Nd:YAG and H₂O₂ showed the greatest reduction in all bacterial viability compared with other treatment groups (p < 0.001). Antiseptic solutions and laser were most effective against P. gingivalis, least effective against S. gordonii but improved significantly in combination with laser irradiation (p < 0.001). Laser alone was effective against all of three bacterial species, however, it was not significant. Conclusions: Combination treatment with Nd:YAG laser and an oxidative disinfectant (0.5% NaOCl or H₂O₂) resulted in more effective reduction of bacterial viability than monotherapies.

Do Lasers Have an Adjunctive Role in Initial Non-Surgical Periodontal Therapy? A Systematic Review

(1) Background: dental lasers have numerous applications for periodontal therapy which include surgical procedures of soft tissue and osseous structures, and non-surgical treatments such as pathogen reduction, removal of surface accretions, and photobiomodulation. The aim of this review was to evaluate the scientific literature to ascertain whether lasers have a beneficial role when used adjunctively in initial non-surgical periodontal therapy. (2) Methods: A PubMed search was performed specifically for randomized clinical trials where a dental laser was used adjunctively for initial periodontal therapy on human patients published from January 2010–April 2020. The first search identified 1294 eligible studies. After additional criteria and filters were applied, 20 manuscripts were included in this review. (3) Results: The chosen manuscripts reported on investigations into initial therapy for patients diagnosed with chronic periodontitis. After periodontal charting, conventional instrumentation such as hand and ultrasonic scaling was performed on all patients in the studies, and then a test group or groups of patients were treated adjunctively with a laser. That adjunctive laser group’s periodontal findings showed various degrees of improved health compared to the group treated with only conventional methods. (4) Conclusion: This systematic review found that 70% of the included studies reported significantly better outcomes in certain clinical parameters, but no improvement in others. The remaining 30% of the manuscripts reported no significant difference in any of the measurements. With consideration to correct parametry, lasers have an adjunctive role in initial non-surgical periodontal therapy.

Effect of scaling and root planing on the expression of anti-inflammatory cytokines (IL-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid of electronic cigarette users and non-smokers with moderate chronic periodontitis

Purpose

The aim of this cross-sectional study was to investigate the effect of scaling and root planing (SRP) on the expression of anti-inflammatory cytokines (interleukin [IL]-4, IL-9, IL-10, and IL-13) in the gingival crevicular fluid (GCF) of electronic cigarette users and non-smokers with moderate chronic periodontitis (CP).

Methods

Electronic cigarette users and non-smokers with CP were included in the study. Full-mouth plaque and gingival indices, probing depth (PD), clinical attachment loss (CAL), and marginal bone loss (MBL) were assessed. The GCF was collected, and its volume and levels of IL-4, IL-9, IL-10, and IL-13 were assessed. These parameters were evaluated at baseline and 3 months after SRP. The sample size was estimated, and comparisons between groups were performed. P<0.05 was considered to indicate statistical significance.

Results

Thirty-six electronic cigarette users (47.7±5.8 years old) and 35 non-smokers (46.5±3.4 years old) with CP were included. At baseline, there were no differences in plaque index (PI), PD, CAL, MBL, and GCF IL-4, IL-9, IL-10, and IL-13 between electronic cigarette users and non-smokers. At the 3-month follow-up, there were no significant differences in PI, gingival index (GI), PD, CAL, and MBL in electronic cigarette users compared to baseline, while there were significant reductions in PI, GI, and PD among non-smokers. At the 3-month follow-up, GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly elevated in both groups (P<0.05) compared to baseline. The increases in GCF IL-4, IL-9, IL-10, and IL-13 levels were significantly higher in non-smokers (P<0.05) than in electronic cigarette users at the 3-month follow-up.

Conclusions

Levels of GCF IL-4, IL-9, IL-10, and IL-13 increased after SRP in electronic cigarette users and non-smokers with CP; however, the anti-inflammatory effect of SRP was more profound in non-smokers than in electronic cigarette users.

[Clinical and microbiologic follow-up evaluations after non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning]

OBJECTIVE

Our research aimed to detect the efficacy of non-surgical periodontal treatment with Nd: YAG laser and scaling and root planning (SRP) for chronic periodontitis.

METHODS

We recruited chronic periodontitis patients who have more than four teeth with clinical pocket depth of 4-8 mm. These teeth were distributed in four different zones within the oral cavity. Moreover, the teeth were single root teeth and not adjacent to each other. The subordinated teeth were randomized into four groups, as follows: no treatment (C group), simple SRP (SRP group), Nd: YAG laser after SRP treatment (SRP+L group), and SRP after Nd: YAG laser treatment (L+SRP group). The four experimental observation points were as follows: before treatment (baseline) and 1 week, 1 month, and 3 months after treatment. We measured clinical indicators and collected subgingival deposits in the four time points to analyze changes of red complex in periodontitis.

RESULTS

The clinical indicators were better in all treatment groups than in the control group. Comparison among treatment groups indicated that the value of bleeding on probing, periodontal probing depth, and clinical attachment loss showed no difference. However, the value of plaque index in SRP+L and L+SRP presented a significant reduction at 3 months after treatment. The percentages of Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in all treatment groups decreased after clinical treatment, and differences were observed among the treatment groups at different time points.

CONCLUSIONS

Non-surgical periodontal treatment with SRP and Nd: YAG laser is not more effective than SRP monotherapy. The sequence of laser treatment and SRP has no significant effect on the treatment. However, SRP with Nd: YAG laser was beneficial for plaque control. Non-surgical periodontal treatment with Nd: YAG laser may be used as an alternative to reduce and control the proliferation of microorganisms in persistent periodontitis, but it still needs further verification.

Impact of cigarette smoking and vaping on the outcome of full-mouth ultrasonic scaling among patients with gingival inflammation: a prospective study

OBJECTIVES

There are no studies that have assessed the oral soft tissue response to full-mouth ultrasonic scaling (FMUS) among cigarette-smokers (CS) (group 1), individuals vaping electronic-cigarettes (E-cigs) (group 2), and never-smokers (NS) (group 3). The aim was to assess the impact of cigarette smoking and vaping on periodontal tissues following FMUS.

MATERIALS AND METHODS

In a clinical prospective study, 89 male individuals were divided into three groups: CS (group 1), E-cig users (group 2), and NS (group 3). A questionnaire was used to gather demographic data and information regarding duration and daily frequency of CS and vaping. Full-mouth plaque index (PI), bleeding on probing (BOP), clinical attachment loss (AL), and probing depth (PD) were measured at baseline and 3 and 6 months after FMUS (without root surface debridement). Numbers of missing teeth (MT) were also recorded.

RESULTS

In groups 1, 2, and 3, 30, 28, and 31 individuals, respectively were included. In group 1, there was no statistically significant difference in mean PI and PD and numbers of sites with PD ≥ 4 mm at 6 months' follow-up compared with baseline and 3 months' follow-up. In groups 2 and 3, there was no significant difference in PI, BOP, and PD at 3 months' (P > 0.05) and 6-months' (P > 0.05) follow-up. There were no pockets with PD ≥ 4 mm at 3 and 6 months' follow-up in groups 2 and 3. There was no difference in the numbers of MT and none of the individuals exhibited clinical AL in all groups.

CONCLUSION

Following FMUS, gingival inflammation is worse in CS compared with individuals vaping E-cigs and NS.

CLINICAL RELEVANCE

Periodontal inflammatory parameters are worse in cigarette-smokers than individuals vaping electronic cigarettes and never-smokers following FMUS. However, these findings should be interpreted with extreme caution as a number of factors may have influenced the present results.

Stimulation of human gingival fibroblasts viability and growth by roots treated with high intensity lasers, photodynamic therapy and citric acid

OBJECTIVE

The aim of this study was to compare the effect of root biomodification by lasers, citric acid and antimicrobial photodynamic therapy (aPDT) on viability and proliferation of human gingival fibroblasts (FGH).

DESIGN

Groups were divided in control (CC - only cells), and root fragments treated by: scaling and root planing (positice control - SC), Er:YAG (ER-60mJ,10pps,10Hz,10s,2940nm), Nd:YAG (ND-0.5W,15Hz,10s,1640nm), antimicrobial photodynamic therapy (PDT-InGaAIP,30mW,45J/cm²,30s,660nm,toluidine blue O), citric acid plus tetracycline (CA). Fibroblasts (6th passage, 2×10³) were cultivated in a 24-h conditioned medium by the treated root fragments. Cell viability was measured by MTT test at 24, 48, 72 and 96h. In a second experiment, FGH cells (10⁴) were cultivated on root fragments which received the same treatments. After 24, 48, 72h the number of cells was counted in SEM pictures. In addition, chemical elements were analyzed by energy dispersive spectroscopy (EDS). Data was analyzed by two-way ANOVA (first experiment), repeated measures ANOVA (second experiment) and ANOVA (EDS experiment) tests complemented by Tukey's test (p<0.05).

RESULTS

ND, PDT and CA promoted higher cell viability (p<0.05). ND and ER groups presented higher number of cells on root surfaces (p<0.05). ER group presented higher calcium and CA group a higher carbon percentages (p<0.05).

CONCLUSIONS

All treatments but scaling and root planing stimulated fibroblast viability while Er:YAG and Nd:YAG treated root surfaces presented higher number of cells.

[Effects of Nd: YAG laser irradiation on the root surfaces and adhesion of Streptococcus mutans]

OBJECTIVE

This study aimed to evaluate the effects of treatment with different powers of Nd: YAG laser irradiation on root surfaces and Streptococcus mutans (S. mutans) adhesion.

METHODS

Extracted teeth because of severe periodontal disease were divided into the following four groups: control group, laser group 1, laser group 2, and laser group 3. After scaling and root planning, laser group 1, laser group 2, and laser group 3 were separately treated with Nd: YAG laser irradiation (4/6/8 W, 60 s); however, the control group did not receive the treatment. Scanning electron microscopy (SEM) was used to determine the morphology. S. mutans were cultured with root slices from each group. Colony forming unit per mL (CFU·mL⁻¹) was used to count and compare the amounts of bacteria adhesion among groups. SEM was used to observe the difference of bacteria adhesion to root surfaces between control group (scaling) and laser group 2 (6 W, 60 s), thereby indicating the different bacteria adhesions because of different treatments.

RESULTS

Morphology alterations indicated that root surfaces in control group contain obvious smear layer, debris, and biofilm; whereas the root surfaces in laser group contain more cracks with less smear layer and debris. The bacteria counting indicated that S. mutans adhesion to laser group was weaker than that of control group (P<0.05). No statistical significance among the laser groups (P>0.05) was observed. Morphology alterations also verified that S. mutans adhesion to laser group 2 (6 W, 60 s) was weaker than that of control group (scaling).

CONCLUSIONS

This study demonstrated that Nd: YAG laser irradiation treatment after scaling can reduce smear layer, debris, and biofilm on the root surfaces as compared with conventional scaling. The laser treatment reduces the adhesion of S. mutans as well. However, Nd: YAG laser irradiation can cause cracks on the root surfaces. In this experiment, the optimum laser power of 6 W can thoroughly remove the smear layer and debris, as well as relatively improve the control of thermal damagee.

Efficacy of scaling and root planning with and without adjunct Nd:YAG laser therapy on clinical periodontal parameters and gingival crevicular fluid interleukin 1-beta and tumor necrosis factor-alpha levels among patients with periodontal disease: A prospective randomized split-mouth clinical study

BACKGROUND AND AIM

Limited evidence exists regarding the role of scaling and root planning (SRP) with adjunct neodymium yttrium aluminum garnet (Nd:YAG) laser therapy in reducing periodontal parameters (plaque index [PI], bleeding on probing [BOP] and probing pocket depth [PPD]) and levels of proinflammatory cytokines in the gingival crevicular fluid (GCF) among patients with periodontal disease (PD). The aim was to assess the effect of SRP with and without adjunct Nd:YAG laser therapy on clinical periodontal parameters and GCF interleukin 1-beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) levels among patients with PD.

METHODS

Demographic data was collected using a questionnaire. Mandibular right and left quadrants were randomly divided into test- (SRP+Nd:YAG laser) and control-sites (SRP alone). PI, BOP and PPD were assessed and GCF IL-1β and TNF-α levels were measured at baseline and at 3- and 6-month follow-up. Level of significance was set at P<0.05.

RESULTS

Twenty-eight male patients with PD were included. At 3- and 6-month follow-up, PI (P<0.01), BOP (P<0.01) and PPD (P<0.01) were significantly higher in the control-sites than test-sites. In the test-sites, PI, BOP and PPD and GCF IL-1β and TNF-α levels were comparable at 3- and 6-month follow-up. At 6-month follow-up, IL-1β (P<0.05) and TNF-α (P<0.05) levels were significantly higher in control-sites than test-sites at 3- and 6-month follow-up.

CONCLUSION

At 3- and 6-month follow-up, SRP+Nd:YAG therapy was more effective in reducing periodontal inflammatory parameters and GCF IL-1β and TNF-α levels compared with SRP alone.

Effect of Nd:YAG laser-assisted non-surgical mechanical debridement on clinical and radiographic peri-implant inflammatory parameters in patients with peri-implant disease

BACKGROUND AND AIM

The efficacy of neodymium-doped yttrium aluminium garnet (Nd:YAG) laser-assisted non-surgical mechanical debridement (MD) in the treatment of periimplant diseases remains uninvestigated. The aim was to assess the efficacy of Nd:YAG laser-assisted non-surgical MD on clinical and radiographic periimplant inflammatory parameters in patients with periimplant disease.

METHODS

Treatment wise, 63 male patients with periimplant diseases were divided into 2 groups: Group-1 (32 patients): treatment of periimplant disease using MD alone (control group); and Group-2 (n=31 patients): treatment of periimplant disease using MD with a single application of Nd:YAG laser. Peri-implant inflammatory parameters (plaque index [PI], bleeding on probing [BOP] and probing depth [PD]) were measured at baseline and at 3 and 6months' follow-up. Periimplant crestal bone loss (CBL) was measured at baseline and at 6months' follow-up. Statistical analysis was performed using the Kruskall-Wallis and Bonferroni Post hoc tests. P-values<0.05 were considered statistically significant.

RESULTS

In both groups, mean age of patients and baseline scores of periimplant PI, BOP and PD were comparable. At 3-month follow-up, scores of periimplant PI, BOP and PD were higher among patients in Group-1 compared with Group-2. At 6-month follow-up, scores of periimplant PI, BOP and PD were comparable among patients in groups 1 and 2. There was no statistically significant difference in periimplant CBL in both groups at all time intervals.

CONCLUSION

Nd:YAG laser-assisted non-surgical MD is more effective in reducing periimplant soft tissue inflammatory parameters than MD alone in short-term but not in long-term.

Periodontal and peri-implant wound healing following laser therapy

Laser irradiation has numerous favorable characteristics, such as ablation or vaporization, hemostasis, biostimulation (photobiomodulation) and microbial inhibition and destruction, which induce various beneficial therapeutic effects and biological responses. Therefore, the use of lasers is considered effective and suitable for treating a variety of inflammatory and infectious oral conditions. The CO2 , neodymium-doped yttrium-aluminium-garnet (Nd:YAG) and diode lasers have mainly been used for periodontal soft-tissue management. With development of the erbium-doped yttrium-aluminium-garnet (Er:YAG) and erbium, chromium-doped yttrium-scandium-gallium-garnet (Er,Cr:YSGG) lasers, which can be applied not only on soft tissues but also on dental hard tissues, the application of lasers dramatically expanded from periodontal soft-tissue management to hard-tissue treatment. Currently, various periodontal tissues (such as gingiva, tooth roots and bone tissue), as well as titanium implant surfaces, can be treated with lasers, and a variety of dental laser systems are being employed for the management of periodontal and peri-implant diseases. In periodontics, mechanical therapy has conventionally been the mainstream of treatment; however, complete bacterial eradication and/or optimal wound healing may not be necessarily achieved with conventional mechanical therapy alone. Consequently, in addition to chemotherapy consisting of antibiotics and anti-inflammatory agents, phototherapy using lasers and light-emitting diodes has been gradually integrated with mechanical therapy to enhance subsequent wound healing by achieving thorough debridement, decontamination and tissue stimulation. With increasing evidence of benefits, therapies with low- and high-level lasers play an important role in wound healing/tissue regeneration in the treatment of periodontal and peri-implant diseases. This article discusses the outcomes of laser therapy in soft-tissue management, periodontal nonsurgical and surgical treatment, osseous surgery and peri-implant treatment, focusing on postoperative wound healing of periodontal and peri-implant tissues, based on scientific evidence from currently available basic and clinical studies, as well as on case reports.

Effect of Water-Cooled Nd:YAG Laser on Dentinal Tubule Occlusion In Vitro

OBJECTIVE

The objective of this study was to investigate the effect of a new water-cooled Nd:YAG laser on dentinal tubule occlusion.

BACKGROUND DATA

The effect of water-cooled Nd:YAG laser on dentinal tubule occlusion has not been reported.

METHODS

Acid-etched dentin samples were randomly divided into three groups: (1) dentin control, (2) dentin treated by Nd:YAG laser, (3) dentin treated by water-cooled Nd:YAG laser. After laser irradiation, half of the samples were immersed in a 6 wt% citric acid (pH 1.5) solution for 1 min to evaluate the acid resistance. The morphologies of dentin surfaces were characterized by scanning electron microscopy. The number and diameters of the open dentinal tubules were analyzed by one-way and two-way analyses of variance.

RESULTS

Both the Nd:YAG laser and water-cooled Nd:YAG laser melted the superficial layer of dentin, which caused dentinal tubule occlusion in most areas and diameter reduction of the rest open tubules. Microcracks on the dentin surface were only observed in the Nd:YAG laser group. The tubule occlusion induced by the two lasers showed a good acid resistance.

CONCLUSIONS

The effect of water-cooled Nd:YAG laser on dentinal tubule occlusion is similar to that of the Nd:YAG laser. The dentinal tubule occlusion induced by the two lasers could resist acid challenge to some extent.

The role of lasers in the treatment of peri-implant diseases: A review

We reviewed the indexed literature regarding the efficacy of laser therapy in the treatment of peri-implantitis (PI). Databases were searched using combinations of the following keywords: peri-implantitis, bone loss, photodynamic therapy, laser, and light-activated disinfection. Titles and abstracts of publications from these search results were screened to determine which studies fulfilled the eligibility criteria. Full texts of relevant studies were read and independently assessed against the eligibility criteria. The resulting 28 studies described the role of lasers in the treatment of PI. The erbium:yttrium–aluminum-garnet laser can be used to sterilize implant surfaces without damaging them. Likewise, the carbon dioxide laser can disinfect implant surfaces and enhance the bone-to-implant contact around previously infected sites. Photodynamic therapy exhibits high target specificity and can destroy pathogens associated with the etiology of PI. Laser therapy can significantly reduce levels of clinical markers of peri-implant tissue inflammation (i.e., bleeding upon probing and clinical attachment loss) without jeopardizing the integrity of the implant or alveolar bone. In conclusion, laser therapy as an adjunct to conventional mechanical debridement therapy can be used effectively for the treatment of PI.

Commentary: Is There Clinical Benefit From Using a Diode or Neodymium:Yttrium-Aluminum-Garnet Laser in the Treatment of Periodontitis?

Despite a quarter of a century of laser research, there is a persistent debate regarding the efficacy of dental lasers in the treatment of periodontitis or periodontal maintenance therapy. There are many claims and much hyperbole surrounding the use of lasers, either as a monotherapy or adjunctive to scaling and root planing, to treat periodontitis. There is little evidence that using a diode or neodymium:yttrium-aluminum-garnet laser adds clinical value over and above conventional non-surgical or surgical periodontal treatment. There is a significant need for better designed human clinical trials. Data from such trials should be analyzed according to initial probing depth and characteristics of the treated sites, such as non-molar, molar flat surfaces, and molar furcations, and evaluated for long-term post-treatment results.

Effect of Nd:YAG laser-assisted non-surgical periodontal therapy on clinical periodontal and serum biomarkers in patients with and without coronary artery disease: A short-term pilot study

BACKGROUND/OBJECTIVE

We hypothesized that nonsurgical-periodontal-therapy (NSPT) with adjunct Nd:YAG laser therapy is more effective in reducing periodontal inflammatory parameters (plaque index [PI], bleeding-on-probing [BOP], and probing-pocket-depth [PPD]) and serum interleukin-1beta (IL-1β) and matrix metalloproteinase-9 (MMP-9) levels in patients with and without coronary artery disease (CAD) than NSPT alone. The aim of this short-term pilot study was to assess the effect of NSPT + Nd:YAG laser therapy on periodontal parameters and serum IL-1β and MMP-9 levels in patients with and without CAD.

STUDY DESIGN

A prospective randomized clinical study was conducted on 87 patients who were divided into two groups: Group-1: 44 patients with CAD and periodontal disease (PD) and Group-2: 43 patients with PD alone. Treatment-wise, these individuals were randomly divided into two subgroups: (i) NSPT alone and (ii) NSPT + Nd:YAG laser therapy. Demographic information was collected using a self-completed questionnaire. Periodontal parameters (PI, BOP, and PPD) and serum IL-1β and MMP-9 levels were measured at baseline and after 3 months of treatment. P-values <0.05 were considered statistically significant.

RESULTS

At 3 months follow-up, PI (P < 0.01), BOP (P < 0.01), PPD ≥ 4 mm (P < 0.01), and serum IL-1β (P < 0.01) and MMP-9 (P < 0.01) levels were significantly higher in patients treated with NSPT alone than those treated with NSPT + Nd:YAG laser therapy. Among patients that underwent NSPT + laser therapy in both groups, periodontal parameters and serum IL-1β, and MMP-9 levels were comparable at 3-months follow-up.

CONCLUSION

NSPT + Nd:YAG laser therapy may be more effective in reducing periodontal inflammation and serum IL-1β and MMP-9 levels in patients with and without CAD than NSPT alone. Lasers Surg. Med. 48:929-935, 2016. © 2016 Wiley Periodicals, Inc.

Trauma from instrumentation after non-surgical periodontal treatment with ultrasonic scalers and Nd:YAG laser

OBJECTIVE

Periodontal therapies aimed at altering the progression of periodontal diseases must include meticulous mechanical debridement during both the non-surgical and the surgical phases of periodontal treatment. The aim of this study was to evaluate and compare the immediate effect of trauma from instrumentation on clinical attachment level after non-surgical periodontal treatment with ultrasonic scalers and a Nd:YAG laser.

MATERIALS AND METHODS

Twenty-four patients with untreated chronic periodontitis, presenting probing depths of 4-6 mm on anterior teeth, upper and lower, were entered into the study. The selected teeth were probed with a pressure-controlled probe, guided by stents. Each quadrant was randomly allocated in a split-mouth design either to treatment with Nd:YAG laser using an energy of 1W, 100mj, 1064nm (test group) or to periodontal treatment using ultrasonic scalers (control group). Clinical parameters, including plaque index (PI), bleeding on probing (BOP), probing pocket depth (PPD) and probing attachment level (PAL) were acquired prior to and immediately after treatment.

RESULTS

Statistical analysis demonstrated no differences between groups at baseline for all parameters (p > 0.05). Immediately after treatment, the control group showed a greater PAL loss than the test group (p < 0.05). For the control group, there were statistically significant differences between PAL immediately before and after treatment (p < 0.05), but not test group (p > 0.05).

CONCLUSIONS

Within the limits of the present study, it may be concluded that non-surgical periodontal treatment with ultrasonic scalers causes a mean immediate attachment loss of 0.68 mm and that a Nd:YAG laser seems to reduce significantly the trauma the instrumentation produced.

Effect of Er,Cr:YSGG laser application in the treatment of experimental periodontitis

The purpose of this study was to evaluate the influence of an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser in the absence or presence of manual scaling and root planning (SRP) for the treatment of induced periodontitis in rats. Ligatures were placed in the subgingival region of the maxillary first molar. After a 7-day period, the ligatures were removed, and 40 rats were randomly divided into four groups (G), as follows: (GI) no treatment, (GII) scaling and root planning (SRP) with curettes, (GIII) Er,Cr:YSGG laser irradiation and (GIV) SRP with curettes followed by Er,Cr:YSGG laser irradiation. Seven and 30 days after the treatment, the animals were sacrificed and histologic, histometric and immunohistochemistry analyses were performed. All groups showed similar histopathological characteristics during the evaluation period. The histometric analysis was confirmed using Bonferroni and paired t tests. At 7 and 30 days, groups II, III and IV exhibited greater bone formation in the furcation area when compared to group I (p < 0.0001; p < 0.05). During the 7-day period, the groups irradiated with the laser (III and IV) showed a statistically larger new bone area than the group treated with SRP (II) (p < 0.01). Immunohistochemistry analysis revealed that the control group exhibited a higher expression of tartrate-resistant acid phosphatase (TRAP) and the receptor activator of nuclear factor κΒ ligand (RANKL) when compared to groups II, III and IV (p < 0.05). All treatments were able to reduce the inflammatory processes, consequently enabling the repair of periodontal tissues. The results achieved with the application of the Er,Cr:YSGG laser suggest that this laser can stimulate greater bone formation, especially over a shorter period of time.

Irradiation by light-emitting diode light as an adjunct to facilitate healing of experimental periodontitis in vivo

BACKGROUND AND OBJECTIVE

This study evaluated the biostimulatory effect of 660 nm light-emitting diode (LED) as an adjunct in the treatment of experimental periodontitis.

MATERIAL AND METHODS

Ninety-six Sprague-Dawley rats underwent experimental periodontitis by placement of a silk ligature followed with or without additive Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) injection. Irradiation with LED light was performed at varying energy densities of 5, 10 and 15 J/cm2, 1 d after debridement and detoxification. Rats were killed at 3, 7 and 14 d after irradiation with LED light, and the effect of irradiation was evaluated by descriptive histology and quantitative measurements of periodontal bone loss, inflammatory infiltration and cellular proliferation.

RESULTS

Reduction of inflammation, accelerated collagen deposition and realignment was noted following irradiation with LED light at densities of 10 and 15 J/cm2, and temporary reduction of periodontal bone loss, as well as bundle bone apposition, was noted at day 3 in rats treated with 10 J/cm2 light. The biomodulatory effect was stronger in sites treated with Pg-LPS injection. In sites without Pg-LPS injection, temporary reduction of inflammation was noted in all LED light-irradiated specimens at day 3. No significant change in cellular proliferation was noted in any LED light-treated group.

CONCLUSIONS

LED light (660 nm) with an energy density of 10 J/cm2 appeared suitable as an adjunct modality for periodontitis by temporarily reducing inflammation, facilitating collagen realignment and bundle bone deposition. Future studies will aim to amplify the biostimulatory effect of LED light by adding a supplementary medium or repeated irradiation.