Comparison of Lasers and Desensitizing Agents in Dentinal Hypersensitivity Therapy

The effect of laser therapy for the treatment of dentin hypersensitivity on surface roughness and bacterial adhesion

The aim of the study was to measure the degree of dentine surface roughness caused by five distinct lasers used to treat dentine hypersensitivity, as well as to evaluate the subsequent bacterial colonization on these irradiated surfaces. Sixty human maxillary premolar teeth without caries or restoration which were extracted for periodontal reasons were used in this study. Five different types of lasers were applied to the root dentin surface. Tested samples were divided into six groups of 10 samples each; control, diode (810 nm), diode (980 nm), Nd: YAG, Er: YAG, and Er, Cr: YSGG laser groups. The arithmetic mean of the surface roughness values (Ra) and the average roughness over a measurement area (Sa) were measured pre- and post-application using any of the laser types. Swab samples were then collected from the dentin surface. Following a 24-hour incubation period at 37 °C, the colony forming units were counted using a stereoscope. The results demonstrated a statistically significant difference in the surface roughness values pre- and post-application (Ra and Sa, respectively) in the Er, Cr: YSGG laser group (p = 0.037,p = 0.007). No significant difference was observed in the other groups (p > 0.05). There was no statistically significant difference in the number of bacterial colonies observed between the test and control groups. Diode and Nd: YAG lasers showed either a decrease or no change in surface roughness; however, the hard tissue lasers (Er: YAG, Er, Cr: YSGG) showed an increase. The Er: YAG and Nd: YAG laser groups exhibited decreased bacterial adhesion compared to the other groups.

Dentinal Tubule Occluding Efficacy Of Er: YAG Laser And Universal Adhesive Loaded With Nano-Carbonated Apatite

ER:YAG laser and experimental resin-based dental adhesive loaded with functionalized carbonated apatite filler were used in this study to evaluate the dentin interaction in terms of penetration and occlusion of the dentinal tubules aiding in the control of dentin hypersensitivity (DH). Spheroidal Carbonated apatite nanoparticles (N-CAP), with an average size of 20±5 nm diameter, were synthesized, characterized, and incorporated in a universal adhesive "All Bond Universal, Bisco, USA", in (2% weight) concentration. Er:YAG laser "Lightwalker, FOTONA, EU" was adjusted to an energy output of 40mJ/ pulse and pulse repetition of 10 Hz for 10 seconds. Dentin specimens were prepared from the buccal surface of 75 extracted sound human molars. The specimens were randomly divided into five groups (n=15) according to the surface treatment: Group (L): Laser only; Group (LB): Laser in combination with adhesive; Group (LBN): Laser in combination with adhesive loaded with N-CAP; Group (B): adhesive only; and Group (BN): adhesive loaded with N-CAP. Depth of penetration and occlusion of the dentinal tubules were assessed using Environmental Scanning Electron Microscope Examination (ESEM). One-way ANOVA was used to compare groups, followed by a pairwise test for multiple comparisons (α=0.05). Groups (LB), and (LBN) showed the highest mean of dentinal tubules' penetration, with a non-significant difference between them. In contrast, the specimens treated with laser only (L) showed the most minor penetration. The employment of ER-YAG laser irradiation with the adhesive loaded with N-CAP was evaluated to be effective in penetrating and occluding the opened dentinal tubules.

A Comparative Study on the Safety and Efficacy of Erbium Laser Therapy Versus Traditional Treatments in Managing Dentin Hypersensitivity: An Observational Study

Background This study aimed to explore the potential efficacy and safety of laser therapy compared with traditional desensitizing treatments in the management of dentin hypersensitivity. Methodology A comprehensive observational study was conducted on 138 adult individuals aged 18-65 diagnosed with dentin hypersensitivity. Participants were allocated to either the laser therapy or traditional treatment group. The laser therapy group received treatment using the Fotona LightWalker® Erbium laser at 2,940 nm. The energy density was set at 20 J/cm² using continuous and contact modes, with the laser tip held perpendicularly to the irradiated site. Each session lasted five minutes, conducted bi-weekly for three months. Traditional treatment included the in-office application of 5% sodium fluoride varnish application once every 15 days for three months and the use of desensitizing toothpaste as part of regular oral hygiene routines. Follow-up assessments were conducted 6 and 12 months post-treatment to evaluate the longevity and stability of the treatment effects. Primary outcomes were assessed by dentin hypersensitivity reduction measured using Visual Analog Scale (VAS) scores and tactile hypersensitivity assessments. Results Laser therapy consistently surpassed traditional treatment in reducing dentin hypersensitivity, as reflected by the significantly lower VAS scores. Notably, at 3, 6, and 12 months, laser therapy demonstrated mean VAS scores of 2.5 (±1.5), 1.2 (±0.9), and 0.6 (±0.5), respectively, while the traditional treatment group exhibited higher scores (3.8 ± 1.2, 4.5 ± 1.0, and 4.0 ± 0.7, respectively). Statistical analysis revealed that these differences were highly significant (p < 0.001). Tactile hypersensitivity assessments echoed these findings, with laser therapy consistently maintaining lower scores (0.8 ± 0.7 at 6 months, 0.4 ± 0.3 at 12 months) compared to traditional treatment (3.5 ± 1.0 at 6 months, 4.0 ± 0.7 at 12 months) with statistical significance at all time points (p < 0.001). Conclusions Although this study lacks a randomized controlled design, the observed substantial reduction in VAS scores and tactile hypersensitivity assessments, along with the favorable safety profile of laser therapy, suggest its potential as an effective alternative for managing dentin hypersensitivity.

EFFECT OF LOW-LEVEL DIODE LASER ON DENTIN TOPOGRAPHY AND SYMPTOMATIC NONCARIOUS CERVICAL LESIONS PRIOR TO COMPOSITE RESTORATIONS: A SPLIT-MOUTH RANDOMIZED CONTROLLED TRIAL

OBJECTIVES

This study assessed alterations in sensitivity among symptomatic noncarious cervical lesions (NCCLs) following the application of 3 low-level diode laser wavelengths before composite restoration. It analyzed the changes in dentin topography using a scanning electron microscope (SEM).

MATERIALS AND METHODS

Nine patients with 36 NCCLs were randomly assigned intra-individually to 4 groups based on the laser wavelength: laser simulation, 445 nm, 660 nm, and 970 nm. Cavity preparation, irradiation, and composite restoration were performed for each lesion. Sensitivity to cold stimuli was recorded using a visual analog scale (VAS) before the intervention (baseline) and at 1 day, 14 days, 1-, 3-, and 6-month. Pulp sensibility was recorded using an electrical pulp tester (EPT) at baseline, before treatment, and at 3- and 6-month. Additionally, an in vitro examination was performed on 12 extracted human molars to yield 12 dentin discs. Each disc was randomly divided into 4 quadrants to receive the same laser wavelengths to determine the diameters of the tubules using SEM. Results were analyzed statistically for clinical studies by the Friedman test, while ANOVA (RM-ANOVA) was conducted in-vitro, followed by the Bonferroni test in the case of significance (P < .05).

RESULTS

VAS readings decreased across all groups, with a significant decrease observed for 660 nm and 970 nm from 14 days to 6-month, while at 445 nm there was a significant decrease at 6-month compared to the control (P < .05). EPT showed a significant decrease in pain threshold levels at 660 nm and 970 nm at 3- and 6-month, while 445 nm showed a significant decrease at 6-month compared to the control (P < .05). The mean tubular diameter at 445 nm decreased, with no significant difference from the control, whereas a significant decrease was found at 660 nm and 970 nm compared to the control (P < .05).

CONCLUSIONS

Prior to composite restoration in symptomatic NCCLs, diode lasers with a wavelength of 660 nm showed the highest reduction in sensitivity, followed by 970 nm, whereas 445 nm diode lasers showed the least reduction. Additionally, diode lasers with wavelengths of 660 and 970 nm reduced the width of the dentinal tubules (DT) without inducing melting, as viewed under SEM.

Ozone and Laser Effects on Dentin Hypersensitivity Treatment: A Randomized Clinical Study

INTRODUCTION

The aim of this study was to evaluate and compare the clinical efficacy of diode laser and ozone gas in the treatment of dentin hypersensitivity (DHS).

METHODS

One hundred thirty-two teeth from 44 patients with moderate DHS were randomized into 3 groups according to a split-mouth design. In the diode laser group, the operator irradiated the superficial dentin exposed with an 808-nm wavelength and incremental power from 0.2 to 0.6 W with a 20-second interval. In the ozone gas group, the operator applied a high dose of ozone (32 g/m3) for 30 seconds using a silicon cup. In the placebo group, no therapy was applied. The dentin sensitivity level was evaluated upon enrollment (T0), immediately after treatment (T1), 3 months post-treatment (T2), and 6 months post-treatment (T3) with a cold air blast challenge and tactile stimuli. The pain severity was quantified according to the visual analogue scale. The Wilcoxon signed rank test was used to scrutinize potential statistical disparities among the treatments. Statistical significance was predetermined at P < .05.

RESULTS

A significant decrease of DHS was observed in the ozone gas group and the `diode laser group immediately after treatment and after 3 and 6 months of the therapy. After 6 months from the therapy, the sensitivity values in the teeth treated with ozone gas remained statistically lower than those treated with diode lasers (P < .05).

CONCLUSIONS

A laser diode and ozone gas are both efficient as dentin sensitivity treatment. Ozone maintains an invariable effectiveness after 6 months.

The Efficacy of Different Laser Applications on Dentin Sealing in Preventing Discoloration Induced by Mineral Trioxide Aggregate

The aim of this in vitro study was to evaluate the effect of the pre-application of a dentin-bonding agent and the application of different lasers on the prevention of tooth discoloration caused by mineral trioxide aggregate (MTA) in the presence of blood. Sixty extracted human anterior teeth were selected, with root lengths standardized to 10 mm and root canals shaped using Gates-Glidden drills #3 to #5. The samples were divided into six groups (n = 10): Group 1 with no surface treatment and Groups 2 to 6 with Optibond universal adhesive and Neodymium yttrium aluminum garnet (Nd:YAG), Erbium yttrium aluminum garnet (Er:YAG), Erbium-chromium-yttrium-scandium-gallium-garnet (Er:Cr:YSGG), and diode laser applications, respectively. Root canals were filled with fresh human blood, and ProRoot MTA and a collagen barrier were then placed. Color changes were measured with a spectrophotometer at 0, 7, 30, 90, and 180 days post MTA placement. Color differences (∆E) were analyzed using a two-factor mixed-design ANOVA with the Sidak method (p = 0.05). All treatment groups exhibited discoloration above the acceptability threshold. Although all treatment approaches exhibited less color change compared to the control group (p < 0.05), there was no significant difference among them in terms of preventing color change (p > 0.05). It was determined that none of the methods could guarantee 100% prevention of discoloration caused by MTA-blood contact.

Er:YAG laser therapy in combination with GLUMA desensitizer reduces dentin hypersensitivity in children with molar-incisor hypomineralization: a randomized clinical trial

This study aimed to investigate the effectiveness of erbium-doped yttrium garnet (Er:YAG) laser and GLUMA desensitizer for dentin hypersensitivity in teeth affected by Molar-Incisor Hypomineralization (MIH). One hundred twenty children were randomly allocated to four groups: the control (Co) group, the desensitizer (De) group, the laser (La) group, and the laser + desensitizer (La + De) group. Outcome measures included Visual Analogue Scale (VAS) and 14-item Oral Health Impact Profile (OHIP-14) evaluation. For mean VAS scores, a significant reduction was found over time in all groups. Co and De groups, Co and La groups, Co and La + De groups, De and La + De groups, and La and La + De groups differed significantly (p < 0.05). For mean scores in all dimensions of OHIP-14 after treatment 6 months, the La + De group was significantly lower (p < 0.001). The La + De groups and the La groups as well as the La + De groups and the De groups differed significantly in total OHIP, functional limitation, physical disability, and psychological disability (p < 0.05). Physical pain between the La + De groups and the La groups and handicap between the La + De groups and De groups differed significantly (p < 0.05). The mean values of each dimension differed significantly between the group Co and the La + De group (p < 0.0001). Combination therapy of Er:YAG laser and GLUMA desensitizer had greater desensitizing effects and oral health-related quality improvement of life, which might be an effective alternative treatment in dentin hypersensitivity in MIH children.

Photobiological modulation of hepatoma cell lines and hepatitis B subviral particles secretion in response to 650 nm low level laser treatment

BACKGROUND

Chronic hepatitis B virus (HBV) infection is a serious global health concern, with an increased incidence and risk of developing cirrhosis and hepatocellular carcinoma (HCC). Patients chronically infected with HBV are likely to experience chronic oxidative stress, leading to mitochondrial dysfunction. Photobiomodulation is induced by the absorption of low-level laser therapy (LLLT) with a red or infrared laser by cytochrome C oxidase enzyme, resulting in mitochondrial photoactivation. Although it is widely used in clinical practice, the use of LLL as adjuvant therapy for persistent HBV infection is uncommon. This study aimed to investigate the effect of LLLT dosage from 2 J/cm2 to 10 J/cm2 of red diode laser (650 nm) on both hepatoma cell lines (HepG2.2.15 [integrated HBV genome stable cell model] and non-integrated HepG2), with a subsequent impact on HBVsvp production.

METHODS

The present study evaluated the effects of different fluences of low-level laser therapy (LLLT) irradiation on various aspects of hepatoma cell behavior, including morphology, viability, ultrastructure, and its impact on HBVsvp synthesis.

RESULTS

In response to LLLT irradiation, we observed a considerable reduction in viability, proliferation, and HBVsvp production in both hepatoma cell lines HepG2.2.15 and HepG2. Ultrastructural modification of mitochondria and nuclear membranes: This effect was dose, cell type, and time-dependent.

CONCLUSIONS

The use of LLLT may be a promising therapy for HCC and HBV patients by reducing cell proliferation, HBVsvp production, and altering mitochondrial and nuclear structure involved in cellular death inducers. Further research is required to explore its clinical application.