Cyanoacrylate Versus Laser in the Treatment of Dentin Hypersensitivity: A Controlled, Randomized, Double-Masked and Non-Inferiority Clinical Trial

Toxicity evaluation of indocyanine green mediated photodynamic therapy

BACKGROUND

The aim of the study is to determine the cytotoxic, genotoxic and inflammatory effects of indocyanine green (ICG) mediated photodynamic therapy (PDT) in direct contact with L-929 mouse fibroblast cells and over a dentin barrier.

METHODS

Eight groups were evaluated; control (C), group with a dentin barrier (D), ICG applied directly on the cells (ICG), ICG applied over a dentin barrier (D-ICG), only laser applied (L), laser applied over a dentin barrier (D-L), ICG and laser applied directly on the cells (ICG-L), ICG and laser applied over a dentin barrier (D-ICG-L). Cell viability was evaluated via ATP Assay, DNA damage was evaluated via Comet Assay, and inflammatory markers IL-1β and TNF-α were assessed via ELISA test.

RESULTS

Cell viability decreased in group ICG (p<0.001). Cell viability decrease was higher in Group ICG-L (p<0.001). Cell viability decrease was lower in group D-ICG-L (p>0.05). Group L caused an increase in cell number (p<0.001). DNA damage was observed in ICG, D-ICG, and ICG-L groups (p<0.05). None of the groups displayed an increase of inflammatory markers IL-1β and TNF-α (p>0.05).

CONCLUSIONS

The presence of dentin between ICG and cells acted as a barrier and protected the cells. ICG-mediated PDT did not cause any cytotoxic, genotoxic or inflammatory effect. The use of ICG-mediated PDT for cavity disinfection is acceptable, but at this concentration its use in periodontal pocket disinfection is not recommended due to its cytotoxic and genotoxic properties.

Effectiveness of Cyanoacrylate in the Treatment of Dentin Hypersensitivity: A Systematic Review

Objective

To compare the effectiveness of cyanoacrylate to other treatments or placebo in the management of dentin hypersensitivity (DH).

Materials and Methods

The present review was organized based on the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. The search aimed to answer the following question: is cyanoacrylate effective in the treatment of DH when compared to other treatments or placebo? The following databases were used: PubMed/MEDLINE, Scopus, BVS, Web of Science, Cochrane, Clinicaltrials.gov, Portal Periódicos Capes, Google Scholar, and manual search. The evaluation process started with the information collected from the selected articles according to the Consolidated Standards of Reporting Trials (CONSORT).

Results

Two randomized and five nonrandomized clinical trials were analyzed in the qualitative synthesis. The studies presented different cyanoacrylate formulations, different scales for evaluating pain, and different methods for provoking a painful stimulus. Cyanoacrylate-based products reduce DH in shorter follow-up periods and this reduction persisted throughout the study. The results varied according to the methods used to stimulate the pain. Only two articles showed a low risk of bias and a high level of scientific evidence.

Conclusion

Although there is a limited number of studies in the scientific literature with appropriate methodological quality, the available evidence proves the effectiveness of cyanoacrylate in the treatment of DH. Clinical Relevance. Cyanoacrylate is easy to access, effective, easily applicable, and a low-cost product with satisfactory results.

The prevalence and predictive factors of dentine hypersensitivity among adults in Turkey

AIM

This study sought to determine the prevalence of dentine hypersensitivity (DH) among adults in Turkey. Also, to ascertain the association between DH and both etiological predictors and demographic patient characteristics.

MATERIAL METHOD

Using a questionnaire and thermal and evaporative tests, 259 women and 209 men in the age range of 18 to 72 were analyzed. Individually, a clinical evaluation of DH signs was conducted. The DMFT index, gingival index, and gingival bleeding were reported for each subject. The gingival recession and tooth wear of sensitive teeth were also evaluated. Pearson Chi-square test was used to compare categorical data. Logistic Regression Analysis was used to examine the risk factors of DH. Data with dependent categorical variables were compared using the McNemar-Browker test. The significance level was p < 0.05.

RESULTS

The average age of the population was 35.6 years. In the present study, a total of 12,048 teeth were analyzed. 1755 had thermal hypersensitivity (14.57%), while 470 experienced evaporative hypersensitivity (3.9%). The incisors were the teeth most impacted by DH, whereas the molars were the least affected. Exposure to cold air and sweet foods, gingival recession, and the presence of noncarious cervical lesions were all strongly linked to DH (Logistic regression analysis, p < 0.05). The cold stimulus increases sensitivity more than the evaporation stimulus.

CONCLUSION

Significant risk factors for both thermal and evaporative DH include cold air, consumption of sweet food, presence of noncarious cervical lesions, and gingival recession. More epidemiological research in this area is still required to fully characterize the risk factors and implement the most effective preventive interventions.

Comparison of Lasers and Desensitizing Agents in Dentinal Hypersensitivity Therapy

The main objective of this review is to verify the validity of laser therapy in the treatment of dentin hypersensitivity, an extremely common problem in patients, with Nd: YAG lasers or high- and/or low-power diode lasers to obtain a definitive protocol for the treatment of hypersensitivity, given the multiplicity of laser treatments proposed by the numerous authors evaluated. The authors performed an electronic search on PubMed, favouring it as a search engine. Lasers represent a means of treating dentin hypersensitivity, used alone and/or in conjunction with specific products for the treatment of such a pathology. The selected articles that examined diode lasers were divided according to the wattage (w) used: low-level laser therapy protocols, i.e., those using a wattage of less than 1 W, and high-level laser therapy protocols, i.e., those using a wattage of 1 W or more. Regarding the Nd: YAG laser, it was not necessary to subdivide the studies in this way, as they used a wattage of 1 W or more. A total of 21 articles were included in the final selection. Laser therapy was found to be effective in the treatment of dentin hypersensitivity. However, the level of effectiveness depends on the laser used. The results obtained from this review show that both the Nd: YAG laser and the diode laser (high and low power) are effective in the treatment of dentin hypersensitivity. However, the high-power laser appears to be more effective in combination with fluoride varnish and the Nd: YAG laser achieved greater long-term benefits than the diode laser.

High-Intensity Red Light-Emitting Diode Irradiation Suppresses the Inflammatory Response of Human Periodontal Ligament Stem Cells by Promoting Intracellular ATP Synthesis

Periodontitis is an inflammatory lesion in the periodontal tissue. The behavior of human periodontal ligament stem cells (hPDLSCs), which play an important role in periodontal tissue regeneration, is restricted by the influence of inflammatory mediators. Photobiomodulation therapy exerts anti-inflammatory effects. The purpose of this study was to investigate the effects of light-emitting diode (LED) irradiation on the inflammatory responses of hPDLSCs. The light source was a red LED (peak wavelength: 650 nm), and the total absolute irradiance was 400 mW/cm². The inflammatory response in hPDLSCs is induced by tumor necrosis factor (TNF)-α. Adenosine triphosphate (ATP) levels and pro-inflammatory cytokine (interleukin [IL]-6 and IL-8) production were measured 24 h after LED irradiation, and the effects of potassium cyanide (KCN) were investigated. LED irradiation at 6 J/cm² significantly increased the ATP levels and reduced TNF-α-induced IL-6 and IL-8 production. Furthermore, the inhibitory effect of LED irradiation on the production of pro-inflammatory cytokines was inhibited by KCN treatment. The results of this study showed that high-intensity red LED irradiation suppressed the TNF-α-stimulated pro-inflammatory cytokine production in hPDLSCs by promoting ATP synthesis. These results suggest that high-intensity red LED is a useful tool for periodontal tissue regeneration in chronically inflamed tissues.

Effects of low-level light therapy on dentin hypersensitivity: a systematic review and meta-analysis

OBJECTIVE

To investigate the treatment efficacy of low-level light therapy on dentin hypersensitivity.

MATERIALS AND METHODS

Following the PRISMA guideline, six electronic databases supplemented with bibliographies were searched till December 2020. Two reviewers performed the screenings independently with a reliability assessment. Studies fulfilling the pre-registered eligibility criteria were included for risk-of-bias assessment and data synthesis.

RESULTS

Thirty-five articles ultimately informed this systematic review based on the eligibility criteria and underwent risk-of-bias assessment (ĸ = 0.86). Quantitative results were deduced by meta-analysis of 20 randomised controlled trials: LLLT showed favourable outcomes compared to placebos for immediate (SMD: 1.09, 95% CI: 0.47 to 1.70), interim (SMD: 1.32, 95% CI: 0.41 to 2.23), and persistent efficacies (SMD: 2.86, 95% CI: 1.98 to 3.74). However, substantial heterogeneity existed among included studies (I2: 64-95%). Regarding comparisons with other desensitising strategies, LLLT showed no significant benefits in DH alleviation over others except fluorides for interim efficacy (SMD: 0.31, 95% CI: 0.10 to 0.52) and persistent efficacy (SMD: 0.45, 95% CI: 0.03 to 0.86).

CONCLUSIONS

This systematic review shows that LLLT has positive immediate, interim, and persistent DH-treatment efficacies compared with placebo. No superior treatment effects of LLLT were observed except fluoride agent use. Further studies are warranted-RCTs with low risk of bias, consistent technical settings, comprehensive assessments, and long follow-up periods.

CLINICAL RELEVANCE

This systematic review bridges a critical research gap by analysing clinical evidence in the DH-alleviating efficacy of LLLT in comparison with placebo and other in-office desensitising strategies.

Laser therapy for dentinal hypersensitivity

BACKGROUND

Dentinal hypersensitivity is characterized by short, sharp pain from exposed dentine that occurs in response to external stimuli such as cold, heat, osmotic, tactile or chemicals, and cannot be explained by any other form of dental defect or pathology. Laser therapy has become a commonly used intervention and might be effective for dentinal hypersensitivity.

OBJECTIVES

To assess the effects of in-office employed lasers versus placebo laser, placebo agents or no treatment for relieving pain of dentinal hypersensitivity.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 20 October 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2020, Issue 9), MEDLINE Ovid (1946 to 20 October 2020), Embase Ovid (1980 to 20 October 2020), CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 20 October 2020), and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; from 1982 to 20 October 2020). Conference proceedings were searched via the ISI Web of Science and ZETOC, and OpenGrey was searched for grey literature. The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomized controlled trials (RCTs) in which in-office lasers were compared to placebo or no treatment on patients aged above 12 years with tooth hypersensitivity.

DATA COLLECTION AND ANALYSIS

Two review authors independently and in duplicate screened the search results, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. For continuous outcomes, we used mean differences (MD) and 95% confidence intervals (CI). We conducted meta-analyses only with studies of similar comparisons reporting the same outcome measures. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

We included a total of 23 studies with 936 participants and 2296 teeth. We assessed five studies at overall low risk of bias, 13 at unclear, and five at high risk of bias. 17 studies contributed data to the meta-analyses. We divided the studies into six subgroups based on the type of laser and the primary outcome measure. We assessed the change in intensity of pain using quantitative pain scale (visual analogue scale (VAS) of 0 to 10 (no pain to worst possible pain)) when tested through air blast and tactile stimuli in three categories of short (0 to 24 hours), medium (more than 24 hours to 2 months), and long term (more than 2 months). Results demonstrated that compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through air blast stimuli at short term (MD -2.24, 95% CI -3.55 to -0.93; P = 0.0008; 13 studies, 978 teeth; low-certainty evidence), medium term (MD -2.46, 95% CI -3.57 to -1.35; P < 0.0001; 11 studies, 1007 teeth; very low-certainty evidence), and long term (MD -2.60, 95% CI -4.47 to -0.73; P = 0.006; 5 studies, 564 teeth; very low-certainty evidence). Similarly, compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through tactile stimuli at short term (MD -0.67, 95% CI -1.31 to -0.03; P = 0.04; 8 studies, 506 teeth; low-certainty evidence) and medium term (MD -1.73, 95% CI -3.17 to -0.30; P = 0.02; 9 studies, 591 teeth; very low-certainty evidence). However, there was insufficient evidence of a difference in pain intensity for all types of lasers when tested through tactile stimuli in the long term (MD -3.52, 95% CI -10.37 to 3.33; P = 0.31; 2 studies, 184 teeth; very low-certainty evidence). Most included studies assessed adverse events and reported that no obvious adverse events were observed during the trials. No studies investigated the impact of laser treatment on participants' quality of life.

AUTHORS' CONCLUSIONS

Limited and uncertain evidence from meta-analyses suggests that the application of laser overall may improve pain intensity when tested through air blast or tactile stimuli at short, medium, or long term when compared to placebo/no treatment. Overall, laser therapy appears to be safe. Future studies including well-designed double-blinded RCTs are necessary to further investigate the clinical efficacy of lasers as well as their cost-effectiveness.

A New Combined Protocol to Treat the Dentin Hypersensitivity Associated with Non-Carious Cervical Lesions: A Randomized Controlled Trial

The goal of this research is to assess the desensitizing effect of a diode laser on non-carious cervical lesions (NCCLs) responsible for dentin hypersensitivity (DH) in two separate output forces implemented both independently and in sequential combination modalities. A randomized controlled trial for this study was applied. Sixty-nine NCCLs responsible for DH pain with severity between 6 and 9 on the VAS scale were considered. Three study groups were developed using just one lesion from three different quadrants of the oral cavity of each patient. All treatment procedures were conducted using a laser diode (810 nm, 5 W) with varying power outputs used separately or in combination. The pain by DH was evaluated at baseline, at treatment completion, and at 15 days and 3 months after each laser procedure. Data analysis was performed using a Wilcoxon test for paired samples, a one-way ANOVA test, and an unpaired t-test. The significant reduction of the mean VAS score was estimated in each study group immediately and at 15 days and 3 months after the end of treatment and compared with the baseline mean VAS score (p-value < 0.0001). The best result concerning the improvement of DH symptomatology was assessed when a combined protocol of two different output powers of the diode laser was used. The authors conclude that the diode laser (810 nm) therapy procedure combining two separate output forces (low and high power) can improve the painful symptoms of DH from NCCLs.

Sensitivity and specificity of assessment scales of dentin hypersensitivity - an accuracy study

The aim of the present study was to compare the sensitivity and specificity of pain scales used to assess dentin hypersensitivity (DH). The preferred scale, and toothbrushing habits of participants were also investigated. This cross-sectional study was conducted with students and employees of a Brazilian Federal University who presented DH. The participants answered a questionnaire about their toothbrushing and drinking habits. Hypersensitive and non-sensitive teeth were submitted to tactile and ice stick stimuli. Then, the subjects marked their pain level in the visual analogue (VAS), numeric scale (NS), faces pain scale (FPS) and verbal evaluation scale (VES). DH was also assessed by Schiff scale (SS). The data were analyzed by Wilcoxon and Chi-Square tests, as well as by ROC curve. The mean age of the sample (56 women, 16 men) was 27.8 years. The most prevalent acidic beverage was coffee (36.0%) and the most preferred scale was the NS (47.2%). The pain level was statistically higher in teeth with DH compared to teeth without DH (p < 0.05). The accuracy ranged from 0.729 (SS) to 0.750 (NS). The highest sensitivity value was 81.9% for NS. The SS presented the highest specificity (91%). The visual analog, numerical, verbal evaluation, faces pain, and Schiff scales were accurate for DH diagnosis. The Schiff scale was the preferred scale for DH assessment.

Photobiomodulation in Endodontic, Restorative, and Prosthetic Dentistry: A Review of the Literature

Objective: To provide a review of the literature about the photobiomodulation therapy (PBMT) dental treatment protocols in endodontic, restorative, and prosthetic dentistry based on validated clinical studies published so far. More specifically, this study was carried out to carefully review therapeutic protocol of PBMT in clinical studies and their conclusions. Background data: The importance of using low-power lasers and photobiomodulation (PBM) is increasing in dentistry mainly due to their painless and noninvasive function. However, lack of sufficient clinical studies has led to unclear results regarding PBMT in dentistry, and also lack of an available precise protocol for clinicians. Moreover, scarcity of clinical studies in this area has made conduction of a precise systematic review study difficult. Methods: In our study, published clinical studies up to April 2019 were reviewed from library sources, Google Scholar, PubMed and Medline, Elsevier, Embase, Cochrane, Scopus, and Web of science (ISI). Inclusion criteria included those presented in clinical trials and case report/case series, language (English), and studies available in full text. Exclusion criterion was in vitro studies. Results: In general, findings of clinical studies have shown that PBMT can have a significant role in reducing postoperative dental pain, increasing depth of anesthesia, improving tooth hypersensitivity, reducing inflammation of the tissue, and helping wound healing. Conclusions: A review of clinical studies showed that the use of alternative or adjunctive PBMT is of great importance in controlling postoperative pain after endodontic treatments. In addition, evidence suggests that different parameters of light can be efficient in the treatment of tooth hypersensitivity. Nevertheless, lack of sufficient clinical studies and reliable results do not allow introducing a precise treatment protocol.

Prevalence of self-reported versus diagnosed dentinal hypersensitivity: a cross-sectional study and ROC curve analysis

OBJECTIVE

This study aimed to identify and compare the self-reported and diagnosed prevalence of dentinal hypersensitivity (DH) in an University population; and to verify accuracy, sensitivity and specificity of DH stimuli tests.

MATERIAL AND METHODS

Three hundred and eighty patients (67.2% women and 32.8% men) were assessed by questionnaire, clinical exam, tactile and cold water tests. The intensity of DH was assessed using a visual analogue scale, and a calibrated examiner measured the scores using a caliper. The ICC for intra-examiner was 0.990. Scores above 5 mm were considered sensitive teeth. The association between variables was assessed by Chi-square test. ROC curve analysis determined accuracy, sensitivity and specificity of the tests (p < .05).

RESULTS

The mean age of participants was 24.08 years. 158 (41.7%) volunteers self-reported the presence of DH, while, 88.7% of the participants were clinically diagnosed (p = .023). In total, 8958 teeth were evaluated, of those 3367 (37.6%) were diagnosed sensitive. The most prevalent teeth with DH were incisors and premolars. The accuracy of the tests with cold water and tactile were 99%. The sensitivity and specificity for cold water and tactile tests were 99.9%, 99.7%, 99.1% and 87.6%, respectively.

CONCLUSION

The self-reported prevalence of DH was significantly lower than that clinically diagnosed. The cold test proved to be a highly accurate stimulus for the diagnosis of DH.

Laser Effects on the Prevention and Treatment of Dentinal Hypersensitivity: A Systematic Review

Introduction: Dentinal hypersensitivity (DH) is an acute intensive tooth pain which can lead to dental annoyances during eating and drinking. Stimulating exposed dentinal tubules by either kind of thermal, tactile, chemical and/or osmotic stimuli is believed to be the cause of this pain. It is hypothesized that dentinal tubules' orifice occlusion (DOO) can help relieve such dental irritations. Thus, this systematic review was conducted to evaluate the effectiveness of laser application as a prevention and treatment modality on DH reduction. Methods: Electronic databases (MEDLINE, SCOPUS) were searched among randomized clinical trials from January 2007 to December 2016. The extraction of data and quality assessments were carried out by different independent observers. Results: A total of 499 items were found of which3 9 relevant articles were extracted. The profound findings proved lasers' effectiveness as a treatment of DH. Although some of the researches reported no significant difference between laser and other desensitizing agents, most of the studies suggested that better results (both rapid and long-lasting) were obtained in combined modalities. Furthermore, the preventive role of this new technology has been emphasized as well. Nd-YAG (neodymium-doped yttrium aluminum garnet) and diode lasers reduce DH after bleaching. Lasers can also protect cervical restorations from DH due to tubular occlusion. Moreover, it is suggested to apply lasers in relief of DH following scaling and root planning. Nevertheless, a few researchers dispute its beneficence as a result of placebo effect. Conclusion: The results obtained from several studies in the present review revealed that the application of lasers is effective not only in terms of treatment of DH, but also in the prevention of this intensive tooth pain. Among various types of lasers, the application of Nd:YAG laser has shown the best results in DH treatment.

Associated factors to cervical dentin hypersensitivity in adults: a transversal study

Background

This cross-sectional study aimed to identify the factors associated to the cervical dentin hypersensitivity (DH) in Brazilian adult population.

Methods

Three hundred and eighty patients (67.2% women and 32.8% men) were assessed by questionnaire and thermal test with ice. Participants marked in a visual analogue scale (VAS) the intensity of pain, and a calibrated examiner (ICC 0.990) measured the scores using a caliper. Pain scores above 0.5 mm were considered sensitive teeth. The DH associated factors were investigated by clinical examination. The association between variables was assessed by Spearman correlation and the Chi-square test. Logistic regression was used to determine the variables that predict DH (p < 0.05).

Results

The mean age of participants was 24.08 years. In this population, 8958 teeth were evaluated, of those 3037 (33.9%) were diagnosed sensitive. The most prevalent associated factors to DH were abnormal tooth positioning (9.0%), occlusal trauma (6.5%) and gingival recession (5.6%). The erosion predicted significantly the DH on both simple (OR 7.85, p < 0.001) and multiple(OR 4.36, p < 0.001) analysis.

Conclusion

The exposure of dentinal tubules by erosion is probably the major predictor of dentin hypersensitivity. The healthy tooth is able to protect against DH.

Evaluation of Tooth Surface Irradiated With Erbium: Yttrium Aluminum Garnet and Carbon Dioxide Lasers by Atomic Force Microscopy

Introduction: Laser irradiation of dentin surface can affect its surface topography and roughness. Atomic force microscopy (AFM) is among the most efficient tools for determination of surface topography of natural biomolecules in nano-scales. Surface roughness affects plaque retention especially in the cervical region. This study aimed to assess and compare the obstruction of dentinal tubules and dentin surface roughness after irradiation of erbium: yttrium aluminum garnet (Er:YAG ) and CO2 lasers for treatment of dentin hypersensitivity (DH). Methods: Five disc-shaped samples measuring 3 mm in thickness were fabricated by horizontal sectioning of the cervical area of five extracted human molars using a low speed saw. Each disc was divided into 3 segments by a bur under water coolant. The three segments of each disc were placed on a glass slide. First segment: No intervention (control group). Second segment: Er:YAG laser irradiation (2940 nm, 50 mJ, 10 Hz and 0.5 W, 30 seconds) along with water coolant. Third segment: CO2 laser irradiation (10600 nm, 80 Hz, 0.3 W, 30 seconds) along with water coolant. After that, the surfaces underwent non-contact AFM. The diameters of dentinal tubules as well as surface roughness were then measured and statistically analyzed using repeated measures ANOVA. Results: The surface roughness parameters (Ra, Rq) showed increased roughness after laser irradiation and this increase in roughness after Er:YAG laser application was significant compared to the control group (P=0.048). However, CO2 laser caused no significant change in surface roughness. Also, after Er:YAG laser application, fewer open dentinal tubules were observed and the remaining open tubules had a smaller diameter. Conclusion: Based on the results, Er:YAG laser irradiation obstructs the dentinal tubules and increases the dentin surface roughness. This increase in surface roughness can cause microbial plaque retention and increase the risk of caries and periodontal disease. Application of CO2 laser (compared to Er:YAG) lead to slight but clinically significant obstruction of dentinal tubules and surface roughness.

Effect of combined application of high- and low-intensity lasers on dentin hypersensitivity: A randomized clinical trial

Background. Diode lasers (DLs) have demonstrated equal or better desensitizing effects than fluoride varnish, 10% potas-sium nitrate (NK) gel and Gluma. The current study evaluated the desensitizing effect of combined application of DLs with two different output powers and compared it with single DL therapy. Methods. Sixty-two hypersensitive teeth were allocated randomly into two groups: the single group was treated with 3-W DL beam once and in the combined group, the teeth were irradiated three times (the first time with 0.2-W and then with 3-W and the second and third times, 48 and 96 hours after the baseline visit, with 0.2-W DL beams). The amount of dentin hyper-sensitivity (DH) was evaluated, immediately before and after each visit, and 1 week and 1 and 3 months after the first visit. Data analysis was performed using chi-squared test, repeated measurement of ANOVA and Mann-Whitney U test. P<0.05 was considered statistically significant. Results. Statistically significant changes were observed in the means of VAS indices between all the measurement intervals and pretreatment measures, in both experimental groups (P<0.001). The difference in VAS reduction among the groups was not significant when the hypersensitive teeth were stimulated by a periodontal probe and a jet of air (P=0.63 and P=0.12). Conclusion. The results of the present study showed that using both high-intensity and combined DL beams gives rise to significant reductions in DH. There was no significant difference between combined and single laser therapies in the treatment of tooth hypersensitivity.

Comparative evaluation of a low-level laser and topical desensitizing agent for treating dentinal hypersensitivity: A randomized controlled trial

Aim

The aim of this randomized, controlled, double-blinded, clinical study is to evaluate and compare the clinical effectiveness of low-level diode GaAlAs laser and glutaraldehyde-based topical desensitizing agent on cervical dentin hypersensitivity with the help of visual analog scale (VAS).

Materials and Methods

Fifty teeth of patients aged between 20 and 50 years were included, and VAS was used to assess the dentin hypersensitivity. The teeth were randomly allocated to either Group 1 or 2 using flip coin technique. Group 1 received glutaraldehyde desensitizer and Group 2 received 905 nm low-level laser. The sensitivity scores were recorded, immediately, after1 week and 3 months after therapy. Data was analyzed using Mann-Whitney U test for intergroup comparison and Friedman's test for intragroup comparison.

Results

There was a significant reduction in pain in both the groups at 3 months evaluation (P = 0.001).However, Group 2 showed a significant decrease in mean VAS scores when compared with Group 1 at both the one week and three month follow ups (P = 0.04, P = 0.03, respectively).

Conclusion

Although topical desensitizer and Low Level Laser are both effective in reducing dentinal hypersensitivity, Low Level Lasers are comparatively more effective at the studied time intervals.

Laser-assisted treatment of dentinal hypersensitivity: a literature review

The purpose of this literature review was to evaluate the effectiveness of the laser-assisted treatment of dentinal hypersensitivity. A review with inclusion and exclusion criteria was performed from January 2009 to December 2014 with electronic data-bases: MedLine via PubMed, Science Direct and Cochrane Library. Research of paper magazines by hand was not considered. Forty-three articles were selected between literature reviews, in vitro studies, clinical trials, pilot and preliminary studies. The items were divided into laser-used groups for an accurate description, and then the reading of results into various typologies. Laser-assisted treatment reduces dentinal hypersensitivity-related pain, but also a psychosomatic component must be considered, so further studies and more suitable follow-ups are necessary.

Evaluation of Low-Level Laser Therapy in TMD Patients

Light amplification by stimulated emission of radiation (laser) is one of the most recent treatment modalities in dentistry. Low-level laser therapy (LLLT) is suggested to have biostimulating and analgesic effects through direct irradiation without causing thermal response. There are few studies that have investigated the efficacy of laser therapy in temporomandibular disorders (TMD), especially in reduced mouth opening. The case report here evaluates performance of LLLT with a diode laser for temporomandibular clicking and postoperative findings were evaluated in two cases of TMD patients. First patient had a history of limited mouth opening and pain in temporomandibular joint (TMJ) region since nine months. Second patient's main complaint was his restricted mouth opening, which was progressed in one year. LLLT was performed with a 685 nm red probed diode laser that has an energy density of 6.2 J/cm(2), three times a week for one month, and application time was 30 seconds (685 nm, 25 mW, 30 s, 0.02 Hz, and 6.2 J/cm(2)) (BTL-2000, Portative Laser Therapy Device). The treatment protocol was decided according to the literature. One year later patients were evaluated and there were no changes. This application suggested that LLLT is an appropriate treatment for TMD related pain and limited mouth opening and should be considered as an alternative to other methods.

A randomized clinical trial of the effect of low-level laser therapy before composite placement on postoperative sensitivity in class V restorations

This study aimed to investigate the efficacy of low-level laser irradiation when applied just before placement of resin composite on reducing postoperative sensitivity of class V lesions. In this randomized clinical trial, 31 patients with 62 class V cavities were included (two teeth in each participant). The teeth were randomly assigned into laser and placebo groups. After cavity preparation, the teeth in the experimental group were subjected to irradiation from a low-power red laser (630 nm, 28 mW, continuous wave, 60 s, 1.68 J), which was applied for 1 min on the axial wall of the cavity. In the control group, the same procedure was performed but with laser simulation. Then, a self-etch adhesive was applied and the cavities were restored with a microhybrid resin composite. Before treatment and on days 1, 14, and 30 after treatment, tooth sensitivity to a cold stimulus was recorded using a visual analogue scale. Data were analyzed by Friedman and Wilcoxon signed-rank tests (p < 0.05). Pain scores after restorative procedures were significantly lower in the laser group compared to the placebo application (p < 0.05). Although both groups experienced a significant improvement in pain and discomfort throughout the follow-up periods (p < 0.001), the changes in visual analogue scale (VAS) scores between baseline and each follow-up examination were significantly greater in the laser than the placebo group (p < 0.05). Low-level laser therapy (LLLT) before placement of resin composite could be suggested as a suitable approach to reduce postoperative sensitivity in class V restorations.

Developments in low level light therapy (LLLT) for dentistry

OBJECTIVES

Low level light/laser therapy (LLLT) is the direct application of light to stimulate cell responses (photobiomodulation) in order to promote tissue healing, reduce inflammation and induce analgesia. There have been significant studies demonstrating its application and efficacy at many sites within the body and for treatment of a range of musculoskeletal injuries, degenerative diseases and dysfunction, however, its use on oral tissues has, to date, been limited. The purpose of this review is to consider the potential for LLLT in dental and oral applications by providing background information on its mechanism of action and delivery parameters and by drawing parallels with its treatment use in analogous cells and tissues from other sites of the body.

METHODS

A literature search on Medline was performed on laser and light treatments in a range of dental/orofacial applications from 2010 to March 2013. The search results were filtered for LLLT relevance. The clinical papers were then arranged to eight broad dental/orofacial categories and reviewed.

RESULTS

The initial search returned 2778 results, when filtered this was reduced to 153. 41 were review papers or editorials, 65 clinical and 47 laboratory studies. Of all the publications, 130 reported a positive effect in terms of pain relief, fast healing or other improvement in symptoms or appearance and 23 reported inconclusive or negative outcomes. Direct application of light as a therapeutic intervention within the oral cavity (rather than photodynamic therapies, which utilize photosensitizing solutions) has thus far received minimal attention. Data from the limited studies that have been performed which relate to the oral cavity indicate that LLLT may be a reliable, safe and novel approach to treating a range of oral and dental disorders and in particular for those which there is an unmet clinical need.

SIGNIFICANCE

The potential benefits of LLLT that have been demonstrated in many healthcare fields and include improved healing, reduced inflammation and pain control, which suggest considerable potential for its use in oral tissues.

Lasers for the Treatment of Dentin Hypersensitivity

This systematic review and meta-analysis assessed the efficacy of lasers in reducing dentin hypersensitivity (DH) as compared with placebo or no treatment. Seven electronic databases and a manual search resulted in 2,538 unique publications. After selection, 13 studies were included in the meta-analysis. A CONSORT-based quality assessment revealed that 3 and 10 studies were at low and high risk of bias, respectively. A random-effects model with the generic inverse variance standardized mean difference (SMD) was used because of expected heterogeneity. Meta-analyses of the baseline-end of follow-up changes in pain revealed no differences for Er,Cr:YSSG vs. placebo (SMD = 2.49; 95% CI, -0.25 to 5.22; p = .07) but did reveal differences in favor of lasers for Er:YAG vs. placebo (SMD, 2.65; 95% CI, 1.25 to 4.05; p = .0002), Nd:YAG vs. placebo (SMD, 3.59; 95% CI, 0.49 to 6.69; p = .02), and GaAlAs vs. placebo (SMD, 3.40; 95% CI, 1.93 to 4.87; p < .00001). High and significant heterogeneity was found for all comparisons. In conclusion, Er:YAG, Nd:YAG, and GaAlAs lasers appear to be efficacious in reducing DH. However, given the high heterogeneity of the included studies, future randomized controlled clinical trials are needed to confirm these results.