Content uploaded by Yuichi Kimura
Author content
All content in this area was uploaded by Yuichi Kimura on Mar 27, 2018
Content may be subject to copyright.
Treatment of dentine hypersensitivity by lasers: A review
Abstract
Since the development of the ruby laser by Maiman in 1960, a variety of papers on potential applications for lasers in dentistry have been published. The purpose of this paper is to summarise laser applications for the treatment of dentine hypersensitivity. The effects of laser on pulp tissue and problems on laser treatment are also reviewed. This article reviews the role of lasers for the treatment of dentine hypersensitivity since 1985, summarises many research reports from the last decade, and surmises what the future may hold for lasers in this treatment.
To date, 4 kinds of lasers have been used for the treatment of dentine hypersensitivity, and the effectiveness ranged from 5.2 to 100%, which was dependent on the laser type and parameters used. The mechanism involved in laser treatment of dentine hypersensitivity are relatively unknown.
These require clarification to result in safely effective treatment optimization. In general, the efficiency for the treatment of dentine hypersensitivity using lasers is higher than other methods, but in severe cases, it is less effective.
It is necessary to consider the severity of dentine hypersensitivity before laser use.
... The using of NaF on hypersensitive tooth mostly results inobliteratepatent dentinal tubules as resulted of precipitation of calcium fluoride crystals consequently control the permeabilityof exposed dentine according to hydrodynamic theory [5]. Another treatment methodology for DH was established with the appearance of laser technology that is progressively utilized in dentistry [6]. The lasers utilized for the treatment of sensitive teeth according to output powers couldbe dividedin two groups: The low-level lasers are helium-neon (He-Ne) and gallium-aluminum arsenide (GaAlAs) (diode) lasers and The middle output power lasers are neodymium doped: yttrium, aluminum, and garnet (Nd:YAG); erbium doped: YAG (Er:YAG); and carbon dioxide (CO2) lasers [7]. ...
... The lasers utilized for the treatment of sensitive teeth according to output powers couldbe dividedin two groups: The low-level lasers are helium-neon (He-Ne) and gallium-aluminum arsenide (GaAlAs) (diode) lasers and The middle output power lasers are neodymium doped: yttrium, aluminum, and garnet (Nd:YAG); erbium doped: YAG (Er:YAG); and carbon dioxide (CO2) lasers [7]. The effect of laser irradiation on dentine surface have explain by several theories, however for the middle output lasers the most acceptable one shows that sealing or occluding the dentinal tubules by melting and re-crystallization of dentine [6] ...
... Although diode laser irradiation at a power of 60mW does not have morphological effect on the surface of enamel or dentine, however this small fraction of the laser energy is transmitted through dental hard tissues to extent the pulp [6]. In our study, the results of combination treatment of NAF+ Diode laser group showed a significant reduction of dentine hypersensitivity by mean of 2.33 before treatment to 0.24 after 30 minutes and this results remain stable after one month. ...
Background: dentin hypersensitivity (DH) is a painful condition that is highly prevalent in the world’s adultpopulation.Aim: The aim of this study was to compare the efficacy of fluoride varnish (5% sodium fluoride)irradiationwith diode laser in the treatment of dentin hypersensitivity in non caries cervical lesion(NCCL) patients.Materials and Methods: Twenty patients with 90 teeth were divided into two groups: Group 1, teeth treatedwith diode laser with5 J/cm2 energy density;Group 2, teeth treated with NaF irradiated with diode laser withsame previous diameter.Results: The two treatments were applied to the buccalcervical region with three follow up intervals 30minutes,2 weeks and one month. The response of the patient to thermal-evaporative stimuli was rated on aSchiff cold air sensitivity scale. The results showed a reduction of hypersensitivity in response to thermalevaporativestimulation at the end of treatment in both groups.Conclusion: dentine hypersensitivity treatment withNaF+diode laser was found to be more effective thanlow-level laser radiationimmediately
... 9 The lasers used for dental hypersensitivity treatment are usually divided into two groups: low-power lasers (He-Ne and GaAlAs lasers), and high-power lasers (Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO 2 lasers). 10 The odontoblasts' cellular metabolic activity increases as a result of the laser photobiomodulating effect on the dental pulp. It obliterates the dentinal tubules to increase the production of tertiary dentin. ...
... Changes in this ratio can impact the organic and inorganic components' relative proportions, which, in turn, can alter dentin permeability and solubility, and affect dental material adhesion. 10 However, our findings indicate that the Ca/P ratios were similar across all groups, and no significant differences were observed. ...
... (2) The obstruction of dentinal tubules by melting. 11,12 The diode laser is a low-intensity laser with 3 wavelengths of 780, 810, 900 nm used in the treatment of hypersensitivity. This laser was first used at a 780 wavelength by Matsumoto et al in 1985 to treat hypersensitivity, and its therapeutic effect is estimated to be 85%-100%. ...
... This laser was first used at a 780 wavelength by Matsumoto et al in 1985 to treat hypersensitivity, and its therapeutic effect is estimated to be 85%-100%. 11 Gluma © desensitizer, which is composed of glutaraldehyde and hydroxyl ethyl methacrylate (HEMA), is among the commercially available desensitizing agents. Glutaraldehyde causes the coagulation of proteins and amino acids in the tubules and is also an effective disinfecting agent. ...
Introduction: Tooth hypersensitivity is among the most common patient complaints caused by the response of exposed dentin to external stimuli. No definite treatment has been suggested so far for dentin hypersensitivity (DH). This study aimed to compare the efficacy of the diode laser alone and in combination with Gluma and chromophore in occluding opened dentine tubules and the treatment of DH. Methods: This in vitro study was conducted on 30 extracted human third molars kept in 0.1% thymol solution. The teeth were mounted in transparent acrylic resin and the buccal enamel was cut to expose the outer third of dentin. The samples were then divided into 6 groups of negative control (no smear layer removal), positive control (smear layer removal with 6% citric acid application), 810 nm diode laser irradiation (energy density 55.55 J/cm2 , 1 W for 20 seconds in a continuous mode), chromophore (1 mg/mL indocyanine green, ICG) plus diode laser irradiation (1 W, 20 seconds), Gluma plus diode laser irradiation, and Gluma + chromophore + diode laser. Dentinal tubules were evaluated under a scanning electron microscope at x2000 magnification. The mean percentage of the obstruction of dentinal tubules was reported as mean and standard deviation. Considering the normal distribution of the data, two-way ANOVA was applied to compare the efficacy of treatments, and an independent-samples t test was used for pairwise comparisons at P<0.05 level of significance. Results: The highest mean percentage of the obstruction of dentinal tubules was noted in the diode laser/chromophore/Gluma group (65.68±12.31%) while the lowest value was noted in the diode laser/Gluma group (24.33±5.90%). Pairwise comparisons revealed significant differences between all groups (P <0.05) except for the difference between the laser/Gluma/chromophore and laser/ chromophore groups (P =0.20). Conclusion: It seems that chromophore increases the efficacy of the diode laser for the obstruction of dentinal tubules.
... 23 This effect, which depends on the relationship between the patient and the dentist to a great extent, might result from a combination of psychological and physiological factors. 24 Researchers believe that patients experience relief due to the placebo effect without receiving any treatment, the extent of which has been reported to be 20%-60% in clinical studies on dentin hypersensitivity. 25 The results of the present study showed improvements in the control group only during the early stages of the study and at other intervals, the control teeth consistently exhibited high dentin hypersensitivity scores. ...
... 31 In clinical and in vitro studies, 635-nm to 830-nm diode lasers have been used for the evaluation of the effect of lowlevel lasers on the treatment of dentin hypersensitivity. 24,32 These laser wavelengths have some effects, including the stimulation of circulation, increasing the biologic activity of cells and also analgesic and anti-inflammatory effects, with the induction of muscular rest. 33,34 Based on physiologic evaluations, the immediate effect of low-level lasers on relieving pain due to hypersensitivity is mediated through the blocking of depolarization of C nerve fibers. ...
Introduction: Dentin hypersensitivity is a common oral problem that occurs as a short and sharp pain. There are many techniques to treat this condition, the latest of which is laser treatment. The aim of this study was to evaluate the effect of two type of low-power diode lasers (660 nm and 810 nm) on dentin hypersensitivity in order to achieve an acceptable clinical application by adjusting the effective parameters.
Materials and methods: In this randomized, double-blind clinical trial, sensitive teeth of 7 patients were divided into three groups with randomized matching method: group I, treated with 660-nm diode laser irradiation; group II, treated with diode laser 810-nm and group III, the control group. Irradiation parameters for 660-nm and 810-nm diode lasers were a power of 30 mW and 100 mW, respectively, in contact and continuous mode, perpendicular to tooth surface with a sweeping motion. Treatments were carried out in four sessions, at weekly intervals. Data obtained were analyzed with SPSS 22, using one-way ANOVA, repeated measures ANOVA and LSD (least significant difference) test. Significance level was considered as a=0.05.
Results: There were no significant differences in VAS score changes between the two laser groups after the intervention in the first, second and third weeks compared to baseline (P>0.05). These changes in the fourth week were significantly higher in the 810-nm laser group compared to the 660-nm laser group (P=0.04) and in the 660-nm laser group were more than the control group (P=0.02). Mean VAS scores at 1-week, 1-month and 2-month postoperative intervals were significantly lower in 810-nm laser group than 660-nm laser group and in the 660-nm laser group they were less than the control group (P<0.001).
Conclusion: The use of 660-nm and 810-nm diode lasers with a power of 30 and 100 mW, respectively, for 120 seconds was effective in reducing pain in patients with dentin hypersensitivity. However, the effect of 810-nm laser was more long lasting in reducing the dentin hypersensitivity than that of the 660-nm laser.
... The effect of suggestion by Placebo and/or self-healing ability by secondary and reparative dentin formation may impact hypersensitivity reduction over time. Pain alleviation is a combination of physiological and psychological interactions greatly influenced by doctor-patient relationship (39). The lack of comparison of the tested agent to a placebo (water) limits the applicability of our study, where instead we contrasted Gluma, a real desensitizing agent, with Scotchbond, a universal adhesive, both of which are claimed to reduce dentin sensitivity. ...
... Lasers:The effectiveness of lasers for treating dentine hypersensitivity varies from 5 to 100 percent, depending on the type of laser and the treatment parameters. (37) Studies have reported that the neodymium: yttrium-aluminum-garnet (YAG) laser, (41) the erbium:YAG laser (67) and galium-aluminium-arsenide low level laser (17) all reduce Dentin hypersensitivity, but the reductions were not significantly different from those of a placebo (41) or positive controls . (17) In addition to these equivocal results, lasers represent a more expensive and complex treatment modality. ...
Introduction: from how to diagnose hypersensitivity to causes and ending by the treatment
... However, laser has become more and more widely used in pediatric dentistry treatment and the appearance of laser therapy provides an alternative way for dentin hypersensitivity. There are some theories to prove the lasting effect of laser irradiation on hypersensitivity, including sealing dentin tubules through melting and resolidification of dentin, evaporation of dentin fluid, analgesic effect related to nerve transmission inhibition, or blocking dentin tubules through third-stage dentin formation [28,29]. ...
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.
Lasers are one of the tooth hypersensitivity treatments. This study aimed to determine the effect of irradiation of Nd:YAG 1064nm and 980nm Diode lasers, used for hypersensitivity treatment, on the shear bond strength (SBS) of metal orthodontic brackets to enamel. Ethylenediaminetetraacetic acid (EDTA) was used to simulate sensitivity in 70 extracted human premolars. The teeth were radiated with 1w Nd:YAG, 1.5w Nd:YAG, 1w Diode, or 1.5w Diode. All samples were incubated at 37° for 24 hours, after bonding the metal brackets. SBS values and adhesive remnant index (ARI) for each tooth was recorded. One-way analysis of variance (ANOVA) and Kruskal-Wallis test were used to compare the mean SBS and the distribution of ARI scores between the study groups, respectively. The SBS mean from the highest to the lowest were in 1w Diode (25.71Mpa), 1w Nd:YAG (24.66Mpa), 1.5w Diode (23.08Mpa), control (21.68Mpa) and 1.5w Nd:YAG (21.53Mpa) groups. No statistically significant difference existed between different groups, in terms of SBS (p=0.211) and ARI distribution (p=0.066). The application of Nd:YAG and 980nm Diode lasers to treat tooth hypersensitivity did not change the SBS of metal orthodontic brackets to the enamel and thus, are harmless to use for orthodontic patients.
Objectives: The aim of this study is to evaluate and compare the bond strength of different dentin desensitizers and self-adhesive resin cements to dentin surfaces. Methods: The flat dentin surfaces of 72 wisdom molar teeth were randomly divided into six groups for bond strength analysis (n=12): Group CP: No desensitizer + Primer II A&B+ Panavia F 2.0, Group CM: No desensitizer+ Primer A&B+ Multilink N, Group TP: Tokuyama Shield Force+ Primer II A&B + Panavia F 2.0, Group TM: Tokuyama Shield Force + Primer A&B+ Multilink N, Group UP: Universal dentin sealant + Primer II A&B+ Panavia F 2.0 and Group UM: Universal dentin sealent + Primer A&B+ Multilink N. The shear bond strength test was performed using a universal testing machine (0.5 mm/min). ANOVA test was used to detect significant differences at a p < 0.05. Results: The results indicated that bond strength values varied according to the desensitizing and resin cement materials (p < 0.05). The Tokuyama Shield Force desensitizer did not affect the bond strength of the resin cements to dentin (p > 0.05). Conclusion: The different types of dentin desensitizer applications affected on the shear bond strength results of the self-adhesive resin cements.
In this study, the effects of dentin ablation using a CO2 laser at 10.6 μm were visualized using a fluorescence technique and confocal laser scanning microscopy. Thirty extracted human teeth showing no clinical signs of caries were investigated. All teeth were horizontally sectioned to approx. 2OO μm thickness and sections were irradiated at different parameters as follows: 3 W [0.01 s pulse duration (p.d.)], 4 W (0.01 s p.d.), and 0.3 W (0.1 s p.d.) using CO2 laser. After laser irradiation, samples were treated with sodium hypochlorite, stained using Rhodamine 123, and observed with confocal laser scanning microscopy followed scanning electron microscope procedure. Surface images obtained using confocal laser scanning microscope were similar to those observed with scanning electron microscopy, but subsurface imaging to a depth of approx. 60 μm which were different from surface ones was achieved using confocal laser microscope techniques. Small effects of laser irradiation were also observable using CLSM easily. This fluorescence technique offers a useful new alternative for visualization and quantification of laser-induced dentin ablation.
Effect of GaALAs semiconductor laser irradiation on activities of the neurons in the trigeminal subuncleus caudalis was electrophysiologically investigated in rats. Extrace llular potentials of the caudal neurons were induced by electric stimulation of the ipsilateral lower incisor pulp and laser irradiation was carried out on the cervical surface of the incisor. Changes in firing discharges and numbers of evoked spikes of the caudal neurons were compared before and after irradiation of the laser.1. Laser irradiation suppressed significantly the late discharges evoked by excitatory inputs from C-fiber afferents, but did not the early discharges evoked by inputs from A δ-afferent fibers.2. Laser irradiation could not suppress wind-up phenomenon of the caudal neurons which was induced by repetitive stimulation of the tooth pulp. However, previous irradiation of the laser before tooth pulp stimulation was effective not to induce wind-up of neurons.3. Non-laser light of a tungsten lamp did not suppress the spike discharges of caudal neurons.4. Reduction in the spike numbers was not significantly observed by the irradiation applied on the “GOUKOKU” point.5. Further investigations about the effect of low power laser irradiation on free nerve endings of C-fiber should be required.
Studies of extracted teeth have shown that teeth exhibiting dentin hypersensitivity have larger numbers of widened dentinal tubules at the dentin surface compared to nonsensitive teeth. Various methods and materials used in the treatment of dentin hypersensitivity are thought to achieve therapeutic benefit by tubule occlusion. However, the effectiveness of semiconductor laser therapy in the reduction of dentin hypersensitivity without tubules occlusion has been reported. The purposes of this investigation were (1) to evaluate the combined effectiveness of semiconductor laser with Duraphat, and (2) to compare the prolonged effectiveness of semiconductor laser with Duraphat and semiconductor laser in the treatment of dentin hypersensitivity. Thirty subjects participated in the randomized, double-blind study, and were followed up for 3 months. Two sites were treated on each patient. One received semiconductor laser treatment and the other received semiconductor laser + Duraphat treatment. Laser treatment consisted of 40-100 mW of power; working time was from 15 to 60 sec; all procedures were performed without local anesthesia. Dentin hypersensitivity was assessed by mechanical stimulus (using a sharp explorer), and thermal stimulus (using a blast of cold air from a dental syringe). Pulpal vitality was measured using an electrical stimulus. The results indicate that immediately following laser treatment and for 3 months thereafter, the subjects' perceived level of discomfort decreased. Semiconductor laser treatment reduced dentin hypersensitivity to air by 70% and to mechanical stimulus by 72% over 3 months. The semiconductor laser + Duraphat treatment reduced dentin hypersensitivity to air by 85% and to mechanical stimulation by 88%. All teeth remained vital after laser treatment, with no adverse reactions or complications. Semiconductor laser and semiconductor laser + Duraphat treatment can be used to reduce dentin hypersensitivity without detrimental pulpal effects.
The purpose of this study is to measure the rate of He-Ne laser transmission through the enamel and dentine to the dental pulp.
He-Ne laser apparatus (CW, 632nm, 6mW) was gotten out “BelBeam”(TAKARA-BERMOND Co), which was used clinically for hypersensitive dentin. Buccal halves of fifteen extracted human permanent tooth crowns were ground successively from the pulpal side and were varied the thickness of them. He-Ne laser was irradiated to the cervicalsurface of specimens and the transmitted laser at different thickness was measured by a Photo Multiplier tube. The measurement was done on the horizontal plane of 180° which was equally divided in 18 points. The total rate of the three dimensional transmission was calculated by integrating these deta.
As a result,the laser transmission showed the exponential increase following to the decrease of tooth structure. The meanpercent of laser transmission was 10.83% in 1.50mm, 8.58% in 1.75mm, 6.05% in 2.00mm, 3.49% in 2.25mm, 3.41% in 2.50mm, 2.35% in 2.75mm, 2.40% in 3.00mm, 1.79% in 3.25mm and 1.20% in 3.50mm thickness.
Studies of extracted teeth have revealed that teeth exhibiting dentin hypersensitivity have larger numbers of widened dentinal tubules at the dentin surface than nonsensitive teeth. Various methods and materials used in the treatment of dentin hypersensitivity are thought to achieve therapeutic benefit by tubule occlusion. The purpose of this investigation was to study the effects of the Nd:YAG laser on exposed dentinal tubules of human extracted teeth using a scanning electron microscope (SEM). Thirty 3-mm- thick slices were cut at the cementoenamel junction from 30 extracted human teeth with an electric saw. A diamond bur was used to remove the cementum layer to expose the dentinal tubules. Each slice was sectioned into four equal quadrants and the inner half of the dentin thickness was removed. The specimens were randomly divided into five groups (A to E). Groups A to D were lased for 2 mins using an Nd:YAG laser at 10 pulses per second at energy outputs of 20, 30, 40, and 50 mJ. Group E served as control. Under SEM observation, nonlased specimens showed numerous exposed dentinal tubules. SEM observation revealed that application of Nd:YAG laser at energy output of 30 mJ may cause melting of dentin and closure of exposed dentinal tubules without dentin surface cracking. But when the energy output is raised to 40 and 50 m J, cracking lines, rupture of molten materials, and exposure of dentinal tubules were noted.