|Year : 2017 | Volume
| Issue : 2 | Page : 34-39
Effect of diode lasers in treatment of dentinal hypersensitivity
Mohammed Mohsen Abdelfattah, Eugenia Anagnostaki
University of Genova, Center of Laser, Genova, Italy
|Date of Web Publication||29-Dec-2017|
Dr. Mohammed Mohsen Abdelfattah
Via Camillo Casarini 3/3, Bologna
Source of Support: None, Conflict of Interest: None
Background: Dentinal hypersensitivity (DH) is characterized by a nonspontaneous, an acute short- or long-lasting pain originating from exposure of the dentinal tubules or dentine to the thermal, chemical, mechanical, or osmotic stimuli, which cannot be attributed to any other dental pathology. There are a lot of treatments; one of these is lasers. Laser therapy was first introduced as a potential method for treating DH in the mid-1980s. Various types of laser used in treatment include low-power lasers He-Ne (632.5 nm), diode lasers (DLs) with various wavelengths 810, 940, and 980 nm, and medium-power lasers as Nd:YAG (1064 nm), CO2 (10600 nm), Er:YAG (2940 nm), and Er, Cr:YSGG (2780 nm). He-Ne (632.5 nm) and DLs have analgesic effect; they can have effect alone or with combination with desensitizing agents. Aim of Study: To appraise and assess the efficiency of different techniques using DLs 810 and 980 nm alone or in combination with different desensitizing agents in the management and treatment of DH. Materials and Methods: A total of 138 articles are included; then, according to exclusion criteria, 46 articles are included; after specific exclusion criteria and evaluation of the articles, they become 35 articles. Regarding exclusion criteria as some titles are not related to the title of literature and discuss other issues, from the 35 articles, there were five systematic review articles and 22 in vivo and 8 in vitro studies. Results: 980 nm and 810 DLs are effective in reduction or treatment of DH alone or in combination with desensitizing agents. DLs and in combination with desensitizing materials are very efficient and precise than treatment done by DLs alone; there is no effect on the pulp tissue as the temperature does not exceed the threshold temperature (5.5°C). Conclusion: 810 and 980 DLs are effective in the treatment and reduction of DH, DLs with different wavelengths alone or with desensitizing materials are efficient, and there is no effect on the pulp tissue as the temperature does not exceed the threshold temperature.
Keywords: Diode lasers, hypersensitivity, low-level laser
|How to cite this article:|
Abdelfattah MM, Anagnostaki E. Effect of diode lasers in treatment of dentinal hypersensitivity. J Dent Lasers 2017;11:34-9
| Introduction|| |
Dentinal hypersensitivity (DH) is characterized by a nonspontaneous, an acute short- or long-lasting pain originating from exposure of the dentinal tubules or dentine to the thermal, chemical, mechanical, or osmotic stimuli, which cannot be attributed to any other dental pathology. DH is a quite common problem. Que et al. pointed out a prevalence of DH varying between 2%–8% and 74%. In patients affected by periodontitis, DH prevalence was even higher ranging between 60% and 98%, this condition may affect patients at any age, and both genders are equally affected. Other terms or definitions used to describe DH have been created by substituting the word dentinal, adding site descriptors, such as cervical or root, and combining this with either hypersensitivity or sensitivity.
The etiology of DH remains unknown, but the most common accepted theory is the fluid movements/hydrodynamic theory proposed by Braennstrom and Astroem, which involves that the movements of fluids of the tubules. These movements of the fluids are direct reactions of thermal, chemical, osmotic, and mechanical stimuli. The odontoblastic processes are indeed rounded by dentinal fluid coming from the pulp complex, which forms 22% of the dentinal volume, and some studies reported that sensitive dentine contains eight times more tubules, but also wider tubules, than not the sensitive teeth.,
Another great problem related to DH is its evaluation since pain is a highly subjective sensation. Nevertheless, it is possible to classify the DH according to the Matsumoto's criteria and visual analog scale (VAS). In this classification, three degrees of DH are recognized: grade 1 – mild discomfort/pain, Grade 2 – moderate pain, and Grade 3 – intense and unbearable pain.
To obtain a conclusive diagnosis of DH, we first carefully evaluate, investigate, and compare among the other teeth, to eliminate other possible causes of pain, which could lead to confusion. A good clinical history is essential and questions asked by the professional may help collect important information that will help in the treatment.
Laser therapy was first introduced as a potential method for treating DH in the mid-1980s. Various types of laser used in treatment such as low-power lasers He-Ne (632.5 nm), diode lasers (DLs) with various wavelengths 810, 940, and 980 nm, and medium-power lasers as Nd: YAG (1064 nm), CO2 (10600 nm), Er: YAG (2940 nm), and Er, Cr: YSGG (2780 nm). He-Ne (632.5 nm) and DLs have analgesic effect; they can have effect alone or with combination with desensitizing agents.
The desensitizing effect of the middle output-power lasers (Nd: YAG, CO2, and Er:YAG) is thought to be related to the occlusion or narrowing of the dentinal tubules. According to hydrodynamic theory, such occlusion could mediate stimulus transmission from the dental surface to the pulp. Only the Nd:YAG laser at 1064 nm seems to have an additional analgesic effect, probably because the irradiation can temporally alter the ending of the sensory axons [Figure 1]. The use of dental lasers has been cited as a possible new treatment option for DH and has become a subject of intensive research in recent decades.
Low-level laser therapy (LLLT) is a sensitizing method that shows promise. This treatment induces alterations within the net of nerve transmission of the dental pulp, instead of altering the exposed dentinal surface, as in most other types of treatment. LLLT has been used for DH since the 1980s. Studies using the gallium aluminum arsenide (GaAlAs) laser showed DH reduction in the range of 60%–98%.
The explanation for the immediate reduction in DH when a low-power DL with an infrared wavelength is used is based on physiological experiments that demonstrated that when light acts on the cell membrane, it allows greater passage and consequent increase in Ca2+, Na2+, and K+ ions. Consequently, the endorphin system and the action potential of neural cells increase, and at the same time, the depolarization of C fiber afferents is blocked, not allowing the pain information to reach the central nervous system., Nd:YAG, Er, Cr:YSGG, and CO2 lasers have ability to melt peritubular dentin, can occlude dentinal tubules partially or totally, and therefore reduce patients' hypersensitivity symptoms.
Aim of the study
To appraise and assess the efficiency of different techniques using DLs 810 and 980 nm alone or in combination with different desensitizing agents in the management and treatment of DH.
| Materials and Methods|| |
A thorough search of literature was performed through PubMed databases.
Words used in the search: diode lasers and hypersensitivity, diode lasers in treatment, dental hypersensitivity, dentinal hypersensitivity, low-power lasers.
- Articles from 2003 to 2016
- Articles in English were only accepted
- In vivo study only
- Articles related to 810 and 980 nm DLs.
- Articles before 2003
- Articles that not related to the literature
- Articles with confusing data and errors
- In vitro study and systematic review.
One hundred and thirty-eight articles are included; then, according to exclusion criteria, 46 articles are included; after specific exclusion criteria and evaluation of the articles, they become 35 articles [Figure 2].
Regarding exclusion criteria as some titles are not related to the title of literature and discuss other issues, from the 35 articles, there were five systematic review articles, 22 in vivo studies, and 8 in vitro studies.
Then, after excluding 12 articles from 22 in vivo studies, 10 articles are discussed in vivo studies related to different wavelengths of DLs alone or in combination with desensitizing agents.
Hence, we conduct a systematic review of 810 and 980 DLs in the treatment or reduction DH [Figure 3].
DLs provide an abundance of available wavelengths in the visible and infrared spectrum. Near infrared lasers are characterized by a high absorption in chromophores found in the soft tissue. The wavelength of a laser determines its level of absorption and interaction with the tissue. The absorption coefficient is a measure of the level of absorption that occurs in a specific tissue by a specific wavelength. A high absorption coefficient means that less energy is needed to get the same local heating effect.
| Diode Laser 980 nm|| |
An innovative 980 nm diode wavelength laser was introduced, which was first reported on 2004. It is a high-energy laser, with low purchase and maintenance costs, as well as greater versatility because of its compact size.,
In vivo study was done by Umberto et al. to discuss the efficacy of a diode GaAlAs laser alone and in combination with topical sodium fluoride gel (NaF) in the treatment of dentine hypersensitivity, this study was done on 10 patients and in total of 115 teeth and classified to three groups first group with GaAlAs laser 980 nm. Each site received three applications of 1 min each once a week for 3 weeks, second group was treated by 1.25% of NaF applied for 60 s on tooth surface, then the last group was treated by NaF gel was left on tooth surface for 60 s before the irradiation with DL 980 nm; in this way, the laser system could favor the permanence of desensitizer for a longer time than when it was used alone.
Umberto et al. found that the GaAlAs laser showed a very high capability to improve immediately the DH-related pain, both alone and even better in combination with NaF gel. On the other hand, the sole gel results, even if positive, cannot equalize the performances of laser in the immediate. Finally, they concluded that combination between laser and desensitizing material achieve the best results.
Suri et al. discuss the effect of DL 980 nm alone and in combination with NaF in reduction of DH, they found that DL 980 nm in combination with NaF reduce DH but NaF alone is better; it was in vivo study that patients classified into four groups: Group 1 was control group, Group 2 (NaF) treated by 5% NaF varnish, Group 3 treated with 980 nm DL, and Group 4 treated with both 5% NaF varnish and 980 nm DL (combination group).
| Diode Laser 810 nm|| |
A randomized, double-blind, controlled, clinical study was done by Yilmaz et al. to compare LLLT with topical fluoride application in the treatment of DH that occurred following scaling and root planing. Patients were classified into four groups as Group 1 treated by GaAlAs, second group were treated by NaF, third group with placebo laser, and finally, Group 4 treated by placebo NaF.
LLLT was performed with GaAlAs DL (with continuous emission (810 nm) on noncontact mode (2 mm from the surface). The laser device was used with the following parameters: output power of 500 mW, irradiation time of 60 s, and 3.5 cm 2 area of active tip resulting in an energy density of 8.5 J/cm 2. In the placebo laser group, the same GaAlAs laser without laser emission was used. GaAlAs laser was applied by scanning the cervical part in an overlapping pattern. In the NaF varnish group, the light yellow varnish was applied with a disposable brush at the cervical region of both the buccal and lingual surfaces strictly. All active and placebo treatments were performed only at the first visit, by the same clinician.
Both the GaAlAs laser and NaF varnish treatments resulted in a significant decrease in the VAS scores immediately after treatments that was maintained throughout the study compared to the baseline scores However, in the NaF group, there was a significant increase in the mean degree of VAS scores at 3 and 6 months compared to at 1 week and 1 month.
Yilmaz et al. had suggested that GaAlAs DL application could be suitable for routine clinical treatment of DH because of the rapid and long-term clinical effectiveness without adverse reactions.
Another study was done by Yilmaz et al. to compare the efficiency and assess the effect of two different wavelengths of lasers DL 810 nm and Er, Cr:YSGG 2780 nm, so it was double clinical study; patients were classified to three groups: first control group, second group patients treated by DL 810 nm, and finally patients treated by Er, Cr:YSGG 2780 nm. Finally, it was concluded that GaAlAs DL 810 nm irradiation seem to be suitable for the treatment for DH, due to the rapid and 3-month clinical effectiveness without adverse reactions.
Hashim et al. found that DL (810 nm) provided a decrease in cervical dentin hypersensitivity (CDH) and the therapeutic immediate and late effects of the DL 810 nm with 60 s exposure duration were greater than those of the 810 nm with 30 s exposure duration. An in vivo study was done to study the effect of the clinical application of the DL (810 nm) in the treatment of DH with two duration time, first group 30 s exposure duration group and the other 60 s exposure duration group, as there is a significant reduction of dentine sensitivity occurred along all times measured during the two treatment sessions in both groups treated with 30 s exposure duration and 60 s exposure duration.
An in vivo study was done by Sicilia et al. on 45 patients to evaluate the immediate efficacy in the reduction of DH when applying an 810 nm DL, and a 10% potassium nitrate bioadhesive gel (NK10%). Patients were classified into three groups as test group (15 patients): treatment with dental laser and placebo gel, second group positive control group (15 patients): treatment with placebo laser and NK potassium nitrate 10% gel, and finally, placebo group (15 patients): treatment with placebo laser and placebo gel. The test group was treated using a dental laser with a wavelength of 810 nm and an inactive fiber not initiated, at an output power of 1.5–2.5 mW, for 1 min or 60 s while a placebo laser was used with the rest of the patients (positive control and placebo groups).
Dental laser can be considered a useful tool for DH reduction in populations of a similar nature, as for instance, patients in periodontal practices. NK 10% gel proved to be effective in the immediate treatment of DH.
Dilsiz et al. found that DL 810 nm have ability to reduce DH by study done to evaluate the effect of DL 810 nm on DH as patients classified into four groups: first group treated with Er: YAG, second one with Nd:YAG, third control group, and last group with DL 810; [Table 1] parameters were power 100 mW and time 20s, but parameters were insufficient, power in continuous or pulsed, contact. or noncontact mode.
According to Lopes et al. the combination of protocols is an interesting alternative in the treatment of CDH was concluded in study done to evaluate the effect of low-power laser and a desensitizing agent on DH, so in vivo study with five groups as Group 1: Gluma desensitizer, Group 2: low-power laser (at low dose three vestibular points and one apical point of irradiation: 30 mW, 10 J/cm 2, 9 s per point with wavelength of 810 nm), three sessions were performed with an interval of 72 h between them; Group 3: low-power laser at high dose (application at one cervical and one apical point: 100 mW, 90 J/cm 2, 11 s per point with wavelength of 810 nm), three sessions were performed with an interval of 72 h between irradiations; Group 4: low-power laser at low dose and Gluma desensitizer; and Group 5: low-power laser at high dose + Gluma desensitizer.
A double-blind controlled trial was done by Femiano et al. to study the DL in association to NaF versus Gluma desensitizer on the treatment of CDH. Four groups were classified as Group 1 were treated with NaF applied with a cotton swab for 60 s, repeated three times at weekly intervals; Group 2 were treated with a DL with these parameters: 0.2 W in continuous emission using a fiber of 320 μm diameter, at a minimum distance from the tooth of 0.5 cm and not more than 1.0 cm, kept perpendicular to the tooth and performing rapid movements apical-coronal and mesiodistal to treat the whole surface of the tooth. Each affected site received three applications of 1 min each once at weekly intervals; Group 3 were treated using both NaF and DL at the same parameters and times of Group 2. The NaF was left on the tooth surface for 60 s before the laser irradiation and finally, Group 4 were treated using a colorless, aromatic fluid containing 36.1% 2-hydroxyethyl methacrylate and 5.1% glutaraldehyde in purified water (Gluma desensitizer applied with a micro brush for 60 s and repeated three times at weekly).
Another study done by Dilsiz et al., in vivo study as patients classified into two groups: the first group which received treatment with desensitizer toothpaste and DL 810 nm and the second group treated with desensitizer toothpaste. Teeth in the test group received laser therapy for three sessions. Parameters of Group 2 were irradiated at 100 mW for 25 s, with continuous emission, noncontact mode, but not mentioned in millimeter, perpendicular to the surface, with the scanning movements on the region of exposed root surfaces. Significant reduction of DH occurred during the three treatment sessions in the test group, Dilsiz et al. conclude that DL 810 can reduce DH.
| Results|| |
980 nm and 810 DLs are effective in reduction or treatment of DH alone or in combination with desensitizing agents.
DLs and in combination with desensitizing materials are very efficient and precise than treatment done by DLs alone; there is no effect on the pulp tissue as the temperature does not exceed the threshold temperature (5.5°C).
| Discussion|| |
The study of Zach and Cohen  defined the temperature thresholds at which can irreversible or reversible pulp damage occurred. When temperature rises above 5.5°C, it resulted in an unacceptable degree of pulpal necrosis. Below this temperature, only mild and reversible pulpitis occurred, while below 2.5°C, no histological changes to the pulpal tissue could be seen. Across the various laser treatment groups, temperature changes at the level of the dental pulp were generally less than 1.5°C, and thus, no deleterious effects would be expected clinically. However, as these measurements were conducted on teeth sectioned in half, the situation in vivo may show changes of lesser magnitude due to increased heat sinking from dentine and the cooling effect of blood flow.
Sgolastra et al. found that lasers are efficient in reduce DH without damage to the pulp and without adverse effect.
Furthermore, Bader et al. found that lasers play an important role in reduce or treatment DH.
| Conclusion|| |
810 and 980 DLs are effective in treatment and reduction of DH, DLs with different wavelengths alone or with desensitizing materials are efficient, and there is no effect on the pulp tissue as the temperature does not exceed the threshold temperature.
Lasers treatment is more comfortable and faster than traditional DH treatment since the time-consuming procedures such as isolation of operation field and repeated applications were eliminated.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Yilmaz HG, Kurtulmus-Yilmaz S, Cengiz E, Bayindir H, Aykac Y. Clinical evaluation of Er, Cr: YSGG and GaAlAs laser therapy for treating dentine hypersensitivity: A randomized controlled clinical trial. J Dent 2011;39:249-54.
Que K, Guo B, Jia Z, Chen Z, Yang J, Gao P, et al.
A cross-sectional study: Non-carious cervical lesions, cervical dentine hypersensitivity and related risk factors. J Oral Rehabil 2013;40:24-32.
Addy M. Dentine hypersensitivity: New perspectives on an old problem. Int Dent J 2002;52:367-75.
Braennstrom M, Astroem A. A study on the mechanism of pain elicited from the dentin. J Dent Res 1964;43:619-25.
Addy M. Dentine hypersensitivity: Definition, prevalence, distribution and etiology. In: Addy M, Embery G, Edgar WM, Orchardson R, editors. Tooth Wear and Sensitivity: Clinical Advances in Restorative Dentistry. London, UK: Martin Dunitz; 2000. p. 239-48.
Miglani S, Aggarwal V, Ahuja B. Dentin hypersensitivity: Recent trends in management. J Conserv Dent 2010;13:218-24.
] [Full text]
Cummins D. Recent advances in dentin hypersensitivity: Clinically proven treatments for instant and lasting sensitivity relief. Am J Dent 2010;23:3A-13A.
Matsumoto K, et al
. Study on the treatment of hypersensitive dentine by Ga-Al-As laser diode. Jpn J Conserv Dent 1985;28:766-71.
Porto IC, Andrade AK, Montes MA. Diagnosis and treatment of dentinal hypersensitivity. J Oral Sci 2009;51:323-32.
Addy M. Etiology and clinical implications of dentine hypersensitivity. Dent Clin North Am 1990;34:503-14.
Suri I, Singh P, Shakir QJ, Shetty A, Bapat R, Thakur R, et al.
A comparative evaluation to assess the efficacy of 5% sodium fluoride varnish and diode laser and their combined application in the treatment of dentin hypersensitivity. J Indian Soc Periodontol 2016;20:307-14.
] [Full text]
Marsilio AL, Rodrigues JR, Borges AB. Effect of the clinical application of the GaAlAs laser in the treatment of dentine hypersensitivity. J Clin Laser Med Surg 2003;21:291-6.
Gerschman JA, Ruben J, Gebart-Eaglemont J. Low level laser therapy for dentinal tooth hypersensitivity. Aust Dent J 1994;39:353-7.
Wakabayashi H, Hamba M, Matsumoto K, Tachibana H. Effect of irradiation by semiconductor laser on responses evoked in trigeminal caudal neurons by tooth pulp stimulation. Lasers Surg Med 1993;13:605-10.
Lan WH, Liu HC. Treatment of dentin hypersensitivity by Nd:YAG laser. J Clin Laser Med Surg 1996;14:89-92.
Gutknecht N, Franzen R, Schippers M, Lampert F. Bactericidal effect of a 980-nm diode laser in the root canal wall dentin of bovine teeth. J Clin Laser Med Surg 2004;22:9-13.
Viapiana R, Sousa-Neto MD, Souza-Gabriel AE, Alfredo E, Silva-Sousa YT. Microhardness of radicular dentin treated with 980-nm diode laser and different irrigant solutions. Photomed Laser Surg 2012;30:102-6.
Umberto R, Claudia R, Gaspare P, Gianluca T, Alessandro del V. Treatment of dentine hypersensitivity by diode laser: A clinical study. Int J Dent 2012;2012:858950.
Yilmaz HG, Kurtulmus-Yilmaz S, Cengiz E. Long-term effect of diode laser irradiation compared to sodium fluoride varnish in the treatment of dentine hypersensitivity in periodontal maintenance patients: A randomized controlled clinical study. Photomed Laser Surg 2011;29:721-5.
Hashim NT, Gasmalla BG, Sabahelkheir AH, Awooda AM. Effect of the clinical application of the diode laser (810 nm) in the treatment of dentine hypersensitivity. BMC Res Notes 2014;7:31.
Sicilia A, Cuesta-Frechoso S, Suárez A, Angulo J, Pordomingo A, De Juan P, et al.
Immediate efficacy of diode laser application in the treatment of dentine hypersensitivity in periodontal maintenance patients: A randomized clinical trial. J Clin Periodontol 2009;36:650-60.
Dilsiz A, Aydin T, Canakci V, Gungormus M. Clinical evaluation of Er:YAG, Nd:YAG, and diode laser therapy for desensitization of teeth with gingival recession. Photomed Laser Surg 2010;28 Suppl 2:S11-7.
Lopes AO, Eduardo Cde P, Aranha AC. Clinical evaluation of low-power laser and a desensitizing agent on dentin hypersensitivity. Lasers Med Sci 2015;30:823-9.
Femiano F, Femiano R, Lanza A, Festa MV, Rullo R, Perillo L, et al.
Efficacy of diode laser in association to sodium fluoride vs. Gluma desensitizer on treatment of cervical dentin hypersensitivity. A double blind controlled trial. Am J Dent 2013;26:214-8.
Dilsiz A, Aydın T, Emrem G. Effects of the combined desensitizing dentifrice and diode laser therapy in the treatment of desensitization of teeth with gingival recession. Photomed Laser Surg 2010;28 Suppl 2:S69-74.
Zach L, Cohen G. Pulp response to externally applied heat. Oral Surg Oral Med Oral Pathol 1965;19:515-30.
Sgolastra F, Petrucci A, Severino M, Gatto R, Monaco A. Lasers for the treatment of dentin hypersensitivity: A meta-analysis. J Dent Res 2013;92:492-9.
Bader J, Balevi B, Farsai P, Flores-Mir C, Gunsolley J, Matthews D, et al.
Lasers may reduce pain arising from dentin hypersensitivity. J Am Dent Assoc 2014;145:e1-2.
[Figure 1], [Figure 2], [Figure 3]