Efficacy of near infrared dental lasers on dentinal hypersensitivity: a meta-analysis of randomized controlled clinical trials

Evaluation of dentinal tubule occlusion and pulp tissue response after using 980-nm diode laser for dentin hypersensitivity treatment

OBJECTIVES

To evaluate the effectiveness of the 980-nm diode laser for dentinal tubule occlusion, measure the intrapulpal temperature, and investigate the dental pulp response.

MATERIALS AND METHODS

The dentinal samples were randomly divided into G1-G7 groups: control; 980-nm laser irradiation (0.5 W, 10 s; 0.5 W, 10 s × 2; 0.8 W, 10 s; 0.8 W, 10 s × 2; 1.0 W, 10 s; 1.0 W, 10 s × 2). The dentin discs were applied for laser irradiation and analyzed by scanning electron microscopy (SEM). The intrapulpal temperature was measured on the 1.0-mm and 2.0-mm thickness samples, and then divided into G2-G7 groups according to laser irradiation. Moreover, forty Sprague Dawley rats were randomly divided into the laser-irradiated group (euthanized at 1, 7, and 14 days after irradiation) and the control group (non-irradiated). qRT-PCR, histomorphology, and immunohistochemistry analysis were employed to evaluate the response of dental pulp.

RESULTS

SEM indicated the occluding ratio of dentinal tubules in the G5 (0.8 W, 10 s × 2) and G7 (1.0 W, 10 s × 2) were significantly higher than the other groups (p < 0.05). The maximum intrapulpal temperature rises in the G5 were lower than the standard line (5.5 ℃). qRT-PCR showed that the mRNA expression level of TNF-α and HSP-70 upregulated significantly at 1 day (p < 0.05). Histomorphology and immunohistochemistry analysis showed that, compared with the control group, the inflammatory reaction was slightly higher at the 1 and 7 days (p < 0.05) and decreased to the normal levels at 14 days (p > 0.05).

CONCLUSIONS

A 980-nm laser at a power of 0.8 W with 10 s × 2 defines the best treatment for dentin hypersensitivity in terms of compromise between the efficacy of the treatment and the safety of the pulp.

CLINICAL RELEVANCE

The 980-nm laser is an effective option for treating dentin sensitivity. However, we need to ensure the safety of the pulp during laser irradiation.

Efficacy of 810 nm and 650 nm Diode Laser Alone and in Combination With Sodium Fluoride Gel in Treating Dentin Hypersensitivity: A Split-Mouth Randomized Clinical Study

Introduction Dentin hypersensitivity has been defined as a short, sharp pain caused by exposing naked dentin to external stimuli such as evaporation, heat, cold, osmotic liquids, and tactile effects. None of the available treatments has been considered the gold standard in treating dentin hypersensitivity. The use of laser has recently become more popular, and it is a promising treatment method in this field. The study aimed to compare the effectiveness of both 810 nm and 650 nm diode lasers in treating dentin hypersensitivity. Materials and methods This study was conducted on six patients who were referred to the Department of Oral Medicine, Faculty of Dental Medicine, Damascus University (4 females and 2 males) with 108 teeth suffering from generalized dentin hypersensitivity and were randomly divided into two groups. Group 1 consisted of three patients with 50 teeth treated with an 810 nm diode laser; it was divided by the split-mouth design into two subgroups. The first subgroup was treated by the application of the laser alone toward the target area with 1-watt power, continuous mode, and a total application time of 90 seconds, and the second subgroup was treated by applying sodium fluoride gel for one minute, then the laser was applied with the same settings as the first subgroup. Group 2 consisted of three patients with 58 teeth treated with a 650 nm diode laser; it was divided by the split-mouth design into two subgroups. The first subgroup was treated by the application of the laser alone toward the target area with 200 m watt power, continuous mode, and a total application time of 120 seconds, and the second subgroup was treated by applying sodium fluoride gel for one minute and then applying the laser with the same settings as the first subgroup. The pain was evaluated using a numeric rating scale (NRS) of 100 degrees before and immediately after treatment, and then after three to six and nine months by applying an air stream from a dental chair syringe at a distance of 0.5 cm from the target area. Results This study showed that both types of lasers were effective in treating pain caused by dentinal hypersensitivity. The average values ​​of pain reduction on the NRS showed the superiority of the 810 nm diode laser over the 650 nm after treatment and at all time points of pain assessment. No statistically significant differences were detected between applying laser alone and applying it combined with sodium fluoride gel in pain reduction values. Conclusions The application of an 810 nm diode laser either alone or in combination with sodium fluoride gel in treating dentin hypersensitivity is effective and better than the application of a 650 nm diode laser either alone or in combination with sodium fluoride gel. In addition, applying a 650 nm diode laser either alone or in combination with sodium fluoride gel has slight effectiveness in treating dentine hypersensitivity, and it is believed that a single treatment session with a 650 nm diode laser was not enough to obtain the required pain reduction.

Can Photobiomodulation Support the Management of Temporomandibular Joint Pain? Molecular Mechanisms and a Systematic Review of Human Clinical Trials

This study aims to point out the correlation between photobiomodulation (PBM) targets and effects and management of temporomandibular disorders (TMDs) pain using diode lasers with infrared wavelengths ranging from 780 up to 980 nanometers (nm). A systematic search of multiple electronic databases was done to identify the clinical trials published between 1st January 2010 and 18th December 2021. The included studies were limited to human subjects who had TMD pain, involving two genders with age > 18 years, and were treated with PBM using a diode laser (780–980 nm) as a non-pharmacological therapy to decrease the intensity of the pain associated to TMDs. The risk of bias for included studies was assessed using the Cochrane RoB tool (for randomized studies). The methodologic quality was rated using the Delphi list. The findings suggest that PBM is an effective tool in alleviating TMDs’ pain and increasing the range of movement in patients with Axis 1 of TMDs. However, TMDs’ pain related to underlying pathology cannot be solely treated by PBM. The causative factors must be treated first. Studies displaying the highest quality Delphi score may represent a suggested PBM therapy protocol to follow for TMDs pain management.