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

Effects of Nd:YAG laser irradiation at different energy densities on dentin bond durability under simulated pulpal pressure

OBJECTIVES

To evaluate the effects of Nd:YAG laser irradiation on the microstructures of dentin surfaces and the long-term bond strength of dentin under simulated pulpal pressure.

MATERIALS AND METHODS

Under simulated pulp pressure, 30 freshly extracted caries-free third molars were cut into 2-mm-thick dentin samples and then divided into five groups: the control and laser groups (93.3 J/cm2; 124.4 J/cm2; 155.5 J/cm2; 186.6 J/cm2). Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and Vickers hardness were used to analyze the surface morphology, composition, and mechanical properties of the dentin before and after laser irradiation. Another 80 caries-free third molars were removed and treated as described above, and the resin was bonded to the dentin surface with Single Bond Universal (SBU) adhesive in self-etch mode to make stick specimens. Microtensile bond strength (µTBS), confocal laser scanning microscopy (CLSM), and interfacial silver nanoleakage tests before and after 10,000 times thermocycling were then performed to analyze the bonding properties and interfacial durability of each group.

RESULTS

SEM observations revealed that the surfaces of all laser group specimens were rough with open dentin tubules. Laser irradiation altered the surface composition of dentin while removing some collagen fibers but did not affect its surface hardness or crystallographic characteristics. Furthermore, laser irradiation with an energy density of 124.4 J/cm2 significantly promoted the immediate and aging bond strengths and reduced nanoleakage compared to those of the control group.

CONCLUSIONS

Under simulated pulp pressure, Nd:YAG laser pretreatment altered the chemical composition of dentin and improved the immediate and long-term bond strength.

CLINICAL RELEVANCE

This study investigated the optimal parameters for Nd:YAG laser pretreatment of dentin, which has potential as a clinical method to strengthen bonding.

Photobiomodulation effects of pulsed and continuous wave near-infrared laser on the proliferation and migration of human gingival fibroblasts: An in vitro study

There are limited data on comparison of pulsed and continuous wave in photobiomodulation therapy (PBM). This study aimed to investigate the effect of PBM with 980 nm laser in pulsed and continuous wave on the proliferation and migration of human gingival fibroblasts (HGF) cells. Cultured HGF were divided into three main groups: (1) irradiated in pulsed mode (frequencies of 50 and 25 KHz; energy densities of 3 and 5 J/cm2 ), (2) irradiated in continuous mode (energy densities of 3.2 and 5.2 J/cm2 ), and (3) no irradiation as control group. HGF proliferation rate was measured by MTT assay at 24, 48, and 72 h post irradiation. In addition, HGF migration rate was measured by scratch test at 24 h post PBM. At 24 h, the group received continuous irradiation at 5.2 J/cm2 showed significantly higher proliferation compared with the control group (p = 0.012). At 48 and 72 h, the groups received continuous, and 50 Hz pulsed irradiation at energy densities of 5.2 and 5 J/cm2 respectively, had significantly higher HGF proliferation rates compared to the control (p < 0.05). Only the continuous irradiations were effective in significant increase of the cell migration. In conclusion, continuous PBM at energy density of 5.2 J/cm2 showed promising effect on HGF proliferation and migration.

Systemic inflammatory markers following adjunctive Nd:YAG (1064 nm) laser irradiation to step 2 of periodontal therapy: a 12-month, randomized, controlled trial

OBJECTIVES

The aim of this study was to investigate whether the use of adjunctive Nd:YAG (1064 nm) laser irradiation to full-mouth scaling and root planing (FM-SRP) may offer additional benefit in the systemic inflammatory status of the patient, as depicted in a variety of systemic biomarkers over FM-SRP alone, up to 12 months after treatment.

MATERIALS AND METHODS

A total of 60 otherwise healthy stage III/IV periodontal patients were equally distributed in 3 groups. The control group received FM-SRP. In laser A group, 1 week after FM-SRP, Nd:YAG laser irradiation was delivered in periodontal pockets with PD ≥ 4 mm using specific settings (3 W, 150 mJ, 20 Hz, 100 μs). In laser B group Nd:YAG laser irradiation was delivered twice, 1 week after FM-SRP and 1 week later with different settings compared to laser A (2 W, 200 mJ, 10 Hz, 100 μs).

RESULTS

A significant reduction (p = 0.038) of IL-1β serum levels at the 6-month time point was observed for laser A group. IL-6 was found statistically significantly increased (p = 0.011) in the control group at the 6-week time point, whereas no difference was reported for the laser-treated groups (laser A, laser B).

CONCLUSIONS

The adjunctive use of Nd:YAG laser irradiation, prevented from IL-6 increase after FM-SRP, 6 weeks after treatment. Similarly, Nd:YAG laser irradiation (3 W, 150 mJ, 20 Hz,100 μs) was associated with significantly lower IL-1β levels, 6 months post-operatively.

CLINICAL RELEVANCE

Additional Nd:YAG laser application to FM-SRP may provide a potential beneficial effect on systemic inflammation.

TRIAL REGISTRATION NUMBER

ISRCTN26692900.

REGISTRATION DATE

09/06/2022.

Nd:YAG laser therapy on postoperative pain, swelling, and trismus after mandibular third molar surgery: a randomized double-blinded clinical study

This study aims to evaluate the effect of Nd:YAG laser therapy (NdLT) on postoperative pain, swelling, and trismus after mandibular third molar (M3) surgery. Three hundred patients were randomly divided into the Nd group (n = 100), medication group (n = 100), and Nd+medication (Nd+m) group (n = 100). The WHARFE classification system was used to assess surgical difficulty. After surgery, the Nd group was irradiated by the Nd:YAG laser in very long-pulsed mode (VLP, pulse duration 1 ms, 20 Hz, 4 W, R21-C3) in 6 regions of the extraction socket with a total energy of 300 J. For the medication group, dexamethasone 0.75 mg and loxoprofen 60 mg were prescribed immediately and every 12 h thereafter for 3 days. The Nd+m group received both treatments mentioned above. Pain assessment was performed at 6, 24, 48, and 72 h postoperatively using the visual analog scale (VAS). Swelling was evaluated by changes in the distance from (1) the tragus to the labial commissure, (2) the tragus to the pogonion, and (3) the mandibular angle to the lateral canthus preoperatively and 72 h postoperatively. Trismus was assessed by the change in maximum mouth opening. Groups Nd and Nd+m had lower VAS scores at 6 h, 24 h, and 48 h (F = 13.80, p = 0.00), but the difference between the two groups was not significant (F = 1.34, p = 0.11). However, no significant difference was observed at 72 h (p = 0.10). There was no significant difference in swelling or trismus among the three groups (p > 0.05). NdLT is an effective approach to improve complications after M3 surgery.

Clinical outcomes of diode laser as an adjunct to nonsurgical periodontal therapy for residual periodontal pockets in mandibular second molars-a randomized controlled clinical trial

OBJECTIVES

The aim of this study was to evaluate the clinical outcomes of diode laser as an adjunct to nonsurgical periodontal therapy (NSPT) for residual periodontal pockets in mandibular second molars.

MATERIALS AND METHODS

Sixty-seven mandibular second molars (154 residual periodontal pockets) were recruited into the study and randomly assigned to the Laser + NSPT group and the NSPT group. The Laser + NSPT group underwent NSPT adjunct with diode laser radiation (wavelength: 810 nm, power: 1.5 W, 40 s maximum), while the NSPT group underwent nonsurgical periodontal therapy alone. Clinical parameters were measured at baseline (T0) and 4(T1), 12(T2), and 24(T3), weeks after treatment.

RESULTS

Periodontal pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BOP) in both groups showed significant improvements at the end of study compared to baseline. The reductions of PPD, CAL, and BOP in the Laser + NSPT group were significantly greater than NSPT group. At T3, the Laser + NSPT group had a mean PPD of 3.06 ± 0.86 mm, CAL of 2.58 ± 0.94 mm and BOP of 15.49%, while the NSPT group had a mean PPD of 4.46 ± 1.57 mm, CAL of 3.03 ± 1.25 mm and BOP of 64.29%.

CONCLUSIONS

The diode laser as an adjunct to nonsurgical periodontal therapy may contribute to clinical outcomes for residual periodontal pockets. However, the approach may cause reduction of keratinized tissue width.

TRIAL REGISTRATION NUMBER

This study was registered in the Chinese Clinical Trial Registry ChiCTR2200061194.

CLINICAL RELEVANCE

Diode laser as an adjunct to nonsurgical periodontal therapy may contribute to the clinical outcomes for residual periodontal pockets in mandibular second molars.

The Clinical and Microbiological Effects of LANAP Compared to Scaling and Root Planing Alone in the Management of Periodontal Conditions

The purpose of this study was to evaluate the efficiency of two therapeutic procedures clinically and microbiologically in the management of periodontally affected teeth: scaling and root planing alone and the laser-assisted new attachment procedure (LANAP). Molecular biological determinations of bacterial markers through the polymerase chain reaction (real-time PCR) method with standard PET tests (species-specific DNA probes at a time) were used for the quantification of three of the most important periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola). Both nonsurgical periodontal therapies were proven effective in patients with chronic periodontal disease; however, LANAP was associated with a greater reduction in pocket depth and improved clinical outcomes, associated with a significant decrease in the amount of Porphyromonas gingivalis. The clinical results included a decrease in periodontal pocket depth, bleeding on probing, and dental plaque, with LANAP having better overall outcomes than SRP alone. The use of Nd:YAG lasers in LANAP therapy is a safe and effective procedure that is well accepted by patients.

Adjunctive Nd:YAG laser irradiation in the treatment of stage III/IV periodontitis: a 12-month, randomized, controlled trial

OBJECTIVES

The aim of this study was to evaluate the clinical efficacy of the adjunctive use of Nd:YAG laser (1064 nm) to full-mouth scaling and root planning (FMS), in stage III/IV periodontitis patients.

MATERIALS AND METHODS

Sixty stage III/IV periodontitis patients were randomly assigned to three groups. The control group received FMS, laser 1 group received combined FMS/single Nd:YAG laser irradiation (3 W, 150 mJ, 20 Hz,100 μs), and laser 2 group received combined FMS/double Nd:YAG laser irradiation with 1-week interval (2.0 W, 200 mJ, 10 Hz, 100 μs). PD, CAL, FMPS, GI, FMBS, and GR were evaluated at baseline, 6 weeks, 3, 6, and 12 months after treatment. Patient-reported outcomes were evaluated 1 week after treatment.

RESULTS

A significant improvement (p < 0.001) for all clinical parameters was observed during the entire study period, with the exception of mean CAL gain for the laser 2 group at 12 months. The percentage of pockets ≤ 4 mm was significantly higher compared to baseline for all groups throughout the study, with no inter-group differences at any time point. Patient-reported analgesic consumption was higher for laser 1 group.

CONCLUSIONS

The adjunctive use of Nd:YAG laser irradiation was similarly effective to FMS alone, during the entire study period. A slightly higher, though not statistically significant improvement was reported for PD at 6 and 12 months after a single post-FMS application of Nd:YAG laser for pocket epithelium removal and coagulation.

CLINICAL RELEVANCE

Additional Nd:YAG laser application for sulcular epithelium removal and coagulation may provide minor long-term improvements compared to FMS or laser irradiation for pocket disinfection and detoxification.

TRIAL REGISTRATION

ISRCTN26692900. Registration date: 09/06/2022.