Dental Hypotheses

ORIGINAL RESEARCH
Year
: 2019  |  Volume : 10  |  Issue : 3  |  Page : 58--64

Effect of Low-Level LASER Therapy on Wound Recovery and Sequelae After Orthognathic Surgery: A Randomized Controlled Trial


Alireza Sadighi1, Hasan Momeni1, Amir Mansour Shirani2,  
1 Department of Oral and Maxillofacial Surgery, Islamic Azad University, Isfahan, Iran
2 Department of Oral Medicine, Faculty of Dentistry, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran

Correspondence Address:
Hasan Momeni
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan
Iran

Abstract

Introduction: Despite the application of low-level laser therapy (LLLT) in diverse dental procedures, its postoperative effects especially on wound recovery after orthognathic surgery have not been well explored. Therefore, the current study aimed to investigate the effects of 660 nm LLLT on postoperative consequences of orthognathic surgery through a randomized controlled trial. Material and Methods: In this split-mouth, triple-blind randomized controlled trial, 12 patients who needed bimaxillary orthognathic surgery were recruited. After the surgery, one side of their face was irradiated with a diode low-level laser device of 660 nm during 1, 2, 4, and 7 days after the surgery, and the other side of their face was considered as placebo. Later, LLLT outcomes were assessed in terms of swelling, pain, and wound recovery after the surgery. For estimating the swelling, distances between tragicus to corner of mouth, tragicus to pogonion, and gonion to cantus were measured; for pain evaluation, the visual analog scale was used. Recovery of wounds was assessed via two ways of probing wounds depth and appraising their clinical features. Results: Although both LLLT and placebo sides presented a constant reduction of swelling over three postoperative months, the swelling in LLLT sides was significantly lower than placebos during the second and fourth days after the surgery. Regarding the pain, there were no significant differences on either sides of the face, 4 days after the surgery. Wounds probing indicated better recoveries at LLLT sides for both upper and lower jaws, whereas the results of clinical features did not show any significant differences between LLLT and placebo sides. Conclusion: LLLT can effectively accelerate the wound recovery after an orthognathic surgery. Also, it is helpful for postoperative sequelae of orthognathic surgery including swelling and pain.



How to cite this article:
Sadighi A, Momeni H, Shirani AM. Effect of Low-Level LASER Therapy on Wound Recovery and Sequelae After Orthognathic Surgery: A Randomized Controlled Trial.Dent Hypotheses 2019;10:58-64


How to cite this URL:
Sadighi A, Momeni H, Shirani AM. Effect of Low-Level LASER Therapy on Wound Recovery and Sequelae After Orthognathic Surgery: A Randomized Controlled Trial. Dent Hypotheses [serial online] 2019 [cited 2019 Dec 15 ];10:58-64
Available from: http://www.dentalhypotheses.com/text.asp?2019/10/3/58/271955


Full Text



 Background



Dentofacial deformity, which mainly affects the jaws and dentition, varies in different races as it depends on genetic and social factors. Patients with severe dentofacial deformity require orthognathic surgery with orthodontic treatment. In orthognathic surgery, the surgeon administers several osteotomies for repositioning the jaw in the right position.[1],[2],[3]

Like any invasive surgeries, the orthognathic surgery negatively influences the patients’ quality of life and requires some postsurgery solutions to overcome the sequelae such as pain, swelling, nausea, trismus, and functional inability.[4],[5] Some suggested postoperative remedies after orthognathic surgery include pharmacotherapy, kinesiology taping, piezoelectric surgery, and light amplification by stimulated emission of radiation application, of which laser therapy has been introduced as a feasible and effective aid in dental surgeries.[6],[7],[8]

Along diverse types of laser therapy, low-level laser therapy (LLLT) with a red or near-infrared light in a narrow spectral width (600–1000 nm) has become a common adjunct treatment in many dental procedures. This popularity of LLLT is partly because of its nonthermal therapeutic effects that prevent the tissue ablation through keeping the target tissue around the same temperature of normal tissues (37°C)[9],[10] and mostly because of its efficacy in pain reduction, local anti-inflammatory management, and wound healing after invasive procedures. This is why the studies in this field did not report any considerable side effects for LLLT have been reported in the literature.[11],[12],[13],[14]

LLLT facilitates and shortens the postsurgery wound recovery through stimulating cell proliferation and increasing tissue vessels.[15],[16] It has been indicated that 660 nm LLLT modulates the cellular viability and upregulates the expression of vascular endothelial growth factor in damaged tissues.[17]

Although several studies examined the effects of LLLT in dental settings such as orthodontics,[18],[19],[20],[21] implantology,[9],[22],[23] teeth surgery,[24],[25],[26] tooth hypersensitivity,[27] and endodontic surgery,[26] its effects after an orthognathic surgery, especially the wound recovery effects, have not been well explored.[28] Therefore, the current study aimed to investigate the effects of 660 nm LLLT on postoperative wound recovery and sequelae of orthognathic surgery through a randomized controlled trial.

 Methods



Patients

In this split-mouth, triple-blind randomized controlled trial, 12 patients aged between 18 and 40 years, who needed bimaxillary orthognathic surgery to correct their dentofacial deformity, were voluntarily recruited from the dentistry clinic of Isfahan Islamic Azad University.

The inclusion criteria were as following: having no facial trauma, oral diseases, or systemic diseases; having no dental or jaws asymmetries; having no requirement of genioplasty in parallel to bimaxillary orthognathic surgery; and being nonsmoker.

Patients were excluded if they had any history of oral cavity and oropharyngeal malignancies or thyroid tumors, were pregnant, had taken the medications which affects wound healing process within at least 6 months before the orthognathic surgery or during the laser therapy, any errors such as bad fracture happened during their orthognathic surgery, got postoperative infection after orthognathic surgery, and showed any allergies to laser therapy.

The study information was provided to each patient before the surgery and they were asked to sign an informed consent before participating in the study. The study was approved by the research ethics board of Isfahan Islamic Azad University and registered at the Iranian Registry of Clinical Trials (http://www.irct.ir/No. IRCT20180312039060N3).

Study design

A surgery of bilateral sagittal split osteotomy and Le Fort I osteotomy for repositioning of the maxilla was administered for all patients. For fixing the jaws in defined positions, four L-shaped plates and 16 screws of 7 mm were used for upper jaws and three screws of 13 mm were used for lower jaws. By end of the surgery, the wounds were sutured with 3-0 VICRYL (Supa, Tehran, Iran). Any prescribed medications before, during, and after the surgery (such as antibiotics) were dosed based on patient’s weight to keep their effects in the same proportions for all participants. Also, all patients underwent the surgery by the same surgeon at the oral and maxillofacial surgery ward of Kashani Teaching Hospital.

After the orthognathic surgery, one side of patient’s face was considered for LLLT and the other side was kept as placebo. For random and equal assignment of facial sides into the study groups, True Random Generator Software, v1.12.2 (ComScire®: The Quantum World Corporation, USA) was occupied.

A 660-nm diode low-level laser device (Hamerz, Tehran, Iran) was used to run the laser therapy sessions. The laser was applied to the surgical incisions on one side of the face (based on the intervention group), 1 cm apart the incised wounds through a forward and backward movement, in the immediate postoperative period at 1, 2, 4, and 7 days after the surgery. The applied laser protocol was as follows: light color = red, wavelength = 660 nm, energy density = 5 J/cm2, exposure time = 100 s/point, and laser power = 50 mw. For placebo sides, laser unit was positioned on the same points as LLLT but the laser was not activated. One oral and maxillofacial surgeon (other than the one who performed the surgeries) administered laser therapy sessions for all patients while they all sat in upright position. Both patients and operator were putting intense pulsed light (IPL) laser safety glasses in time laser application, and the patients were under supervision for any side effects of LLLT such as burns or erythema.

The patients were blinded to irradiated and nonirradiated sides of their face. In addition, to ensure blinding, one investigator with no clinical involvement in the study allocated the facial sides into the study groups and another investigator, who was blinded to the study groups, assessed postoperative outcomes. Also, statistical data analyst remained blinded to both patients and laser administrator.

By aiming for a confidence level of 95% and 80% power for a crossover trial study, the Pocock formula[29] calculated the sample size as 11 patients. To allow for a dropout rate of 10%, the sample size was increased to 12 samples.

Outcome measurements

Postoperative outcomes were assessed regarding swelling, pain, and wound recovery. The outcomes were first assessed immediately 1 day after the surgery to collect their baseline values.

Swelling size was estimated using the formula of Carrillo et al.[30] Thus, the mean distances between tragicus to corner of mouth, tragicus to pogonion, and gonion to cantus were measured in millimeters using a soft ruler. The swelling measurements were performed by end of each LLLT sessions (1, 2, 4, and 7 days after the surgery) and repeated during 2, 3, 4, 8, and 12 postoperative weeks.

Pain intensity was assessed with visual analog scale[31] during 1, 4, 7, and 14 days after the surgery. For this purpose, the patients were asked to report their pain at each facial sides in a scale of 0 to 10, where 0 referred to absence of pain and 10 presented the maximum level of pain.

Recovery of postsurgery wounds was appraised via two ways. The first way was probing the depth of wounds and the second was assessing their clinical features. In probing way, a periodontal probe (Joya, Iran) was used to measure the mean depth of three points that divided the wound into four equivalent parts. The wounds of upper and lower jaws at each study groups were separately probed over 1, 7, and 14 days after the surgery. For assessing the clinical features of wounds, every surgical wound at right and left parts of each upper and lower jaws were photographed by a camera (Canon, PowerShot G11, Tokyo, Japan), 4 cm apart of commissure of lips, without focus and from a close-up view. The photographs were sent to three oral and maxillofacial surgeons as referees (who were not involved in the study) and were asked to compare the wounds recovery at right versus left sides of upper and lower jaws and vote for the photograph with better recovery features. Thereafter, data formed from their votes were compared for upper and lower jaws separately.

Statistical analyses

Data were analyzed using Stata version 15.1 software. The normality of the distribution of data was evaluated by a one-sample Kolmogorov–Smirnov test. Baseline measurements were compared using independent Student t test and Mann-Whitney U test for normal and unnormal variables, respectively. For comparison of data between measurements and identify any differences between the study groups, data were adjusted for baseline measurements through analysis of covariance (ANCOVA) analysis. For unnormal variables, ANCOVA analysis was performed after logarithmic transformation. P values of <0.05 were considered to be statistically significant. Descriptive statistics were reported as mean (standard deviation) for normal data and geometric mean (confidence interval) for unnormal data.

 Results



Participants

A total of seven female and five male patients with a mean age of 28.7 ± 6.1 years underwent the bimaxillary orthognathic surgery. The mean duration of the surgeries was 122 ± 1.3 minutes. Thereafter, all patients took part in LLLT sessions regularly with no exclusions [Figure 1]. No adverse effects or symptoms following the surgery or LLLT was observed in study patients.{Figure 1}

Baseline characteristics

With respect to split-mouth design of study, baseline characteristics of the participants were out of consideration, but regarding baseline measurements, there were no significant differences between LLLT and placebo groups in swelling [Table 1], pain [Table 2], probing of upper and lower jaws [Table 3], and clinical features of upper and lower jaws [Table 4].{Table 1}{Table 2}{Table 3}{Table 4}

Efficacy

Swelling

The average measures of swelling for placebo and LLLT groups are presented in [Table 1]. Although both the groups presented the highest amounts of swelling over the second postoperative day, their swelling kept a constant reduction over the time and ended up with the lowest amounts over the third postoperative month [Figure 2]. The differences between the groups showed up during the second (P < 0.05) and fourth (P < 0.05) days after the surgery, where the swelling was significantly lower in LLLT group compared to placebo for around 1 mm. Other swelling measurements did not demonstrate any significant differences between the two groups [Table 1].{Figure 2}

Pain

Pain assessments did not reveal any differences between irradiated and nonirradiated groups, but during the fourth (P < 0.05) postsurgery day [Table 2].

Wound recovery

Wounds probing indicated significant differences over the first (P < 0.05) and second (P < 0.05) postsurgery weeks between the study groups. The LLLT group presented better recovery of wounds in both upper and lower jaws [Table 3], whereas the results of clinical features did not show any significant differences between the groups [Table 4].

 Discussion



The growing interest in using LLLT as a supplement of dental procedures is based on providing an improved treatment with minimally pain for patients. There is a great need for postsurgical management protocols that could increase the comfort and general health after orthognathic surgery. Although controlling the postoperative consequences such as pain and swelling is needed to make the patients comfortable, any progress in wound recovery can improve their general health. However, there is insufficient evidence in the literature for effectiveness of LLLT in improving the postoperative consequents, it has been introduced as a new approach toward the managing of postoperative process in dental settings.[5],[28] In the current study, we assessed the LLLT effects on improving the consequents after orthognathic surgery.

Our measurements over recovery of surgical wounds yield that LLLT can effectively accelerate the wounds recovery at both upper and lower jaws after orthognathic surgery. Although the evidence for wounds recovery has been provided by probing the depth of wounds, the clinical features of wounds did not present any advantages for LLLT. Ozcelik et al.[32] also indicated that LLLT has a positive effect on epithelization and wound healing after gingivectomy and gingivoplasty surgeries.

It is assumed that the LLLT at a specific wavelength results in biostimulation or the biomodulation effects that can alter the cellular behavior. In detail, LLLT effects the cellular mitochondrial respiratory chain or membrane calcium channels that causes an increase in cell metabolism and proliferation through facilitating fibroblast and keratinocyte cell motility, collagen synthesis, angiogenesis, and growth factor release; this process finally leads to an improvement in wound healing.[11],[32] Wagner et al.[33] studied the effect of LLLT on cytokine and angiogenesis levels in oral wounds and demonstrated that photobiomodulation can regulate the cytokine level that increases the angiogenesis level and improves the healing process of oral wounds.

Regarding the sequelae after orthognathic surgery, we observed that the average amounts of swelling in both the groups constantly reduced over the time, but the swelling size in LLLT group was significantly lower than placebo only during the second and fourth days after the surgery. Since it has been reported that 50% of facial swelling resolves within the first 3 weeks after orthognathic surgery,[4] the positive effects of LLLT during the preliminary postoperative days are much expected than long-term periods; although other swelling measurements especially the long term did not show a considerable difference between the two groups in our study, the swellings in LLLT sides showed a faster reduction of around 1 mm compared at preliminary postoperative days. On the other hand, our findings indicated that LLLT can accelerate the early-term swelling resolve in patients who underwent an orthognathic surgery. Albertini et al.[34] also showed that LLLT (660 nm) can effectively decrease the edema formation and inflammatory cell migration. In parallel, Gasperini et al.[28] indicated that LLLT has significant anti-inflammatory actions that lead to a reduction in swelling and pain after an orthognathic surgery.

In the current study, while the levels of patients’ pain were assessed over 2 weeks after the orthognathic surgery, the patients only reported a significant lower pain at LLLT facial side during the fourth postoperative day. It has been reported that pain intensity is more controllable during the preliminary days after the injury when the injury is in inflammatory phase. Also, it has been observed that as the tissue keeps processing in recovery, the pain level decreases.[12] The significant reduction of swelling and faster wound recovery over the first postoperative week would be the potential sources of pain management in our patients during the preliminary days after the orthognathic surgery.Although our findings regarding the reduction of swelling and pain after LLLT were at the same direction of results that were published by several dentistry studies,[6],[30],[35],[36] Roynesdal et al.[37] reported that LLLT has no effect on postoperative reduction of swelling or pain after third molar surgery; also D’ávila et al.,[38] who administered the LLLT after orthognathic surgery, confirmed the reduction in pain levels while rejected any positive effects of LLLT on swelling.[38]

Since the ideal LLLT protocol for managing the consequences of orthognathic surgery has not yet been developed,[12] the variations in LLLT protocol at different studies could be the source of different findings between them.

Despite the strengths of the current study in terms of parallel assessment of LLLT outcomes in a period of 3 months after the orthognathic surgery, it limited the sample for the 18 to 40 years’ age group that made the elderlies, who more sensitive to pain and more resident to wound healing, out of consideration; thus, further studies are suggested to investigate the effects of LLLT on postoperative outcomes of orthognathic surgery in elderlies. Also, comparing the wound recovery outcomes between 660 and 810 nm LLLTs may lead to a better LLLT protocol after a orthognathic surgery.

 Conclusion



The current study assessed the effects of LLLT (660 nm) on postoperative outcomes of orthognathic surgery including wound recovery, swelling, and pain. The results indicated that LLLT can effectively accelerate the wounds recovery at both upper and lower jaws over 2 weeks after an orthognathic surgery. Also, LLLT is helpful for postoperative swelling and pain over 2 to 4 days and 4 days, respectively, after the orthognathic surgery.

 Acknowledgement



We would like to thank the patients who participated in our study and completed all LLLT and follow up sessions, and would also like to specially thank Raana Zakeri for her great helps in data analysis and manuscript improvement.

Financial support and sponsorship

This study was funded by Isfahan (Khorasgan) branch of Islamic Azad University.

Conflicts of interest

There are no conflicts of interest.

References

1Wilmot JJ, Barber HD, Chou DG, Vig KWL. Associations between severity of dentofacial deformity and motivation for orthodontic-orthognathic surgery treatment. Angle Orthod 1993;63:283-8.
2Hernandez SC, Hofer TD, Carrasco EC, Martinez CP. Epidemiological study of patiens with Dentofacial deformities treated at San Borja Arriaran Clinical Hospital, Santiago of Chile. J Oral Maxillofac Surg 2014;72:e138.
3Tozzi U, Santagata M, Sellitto A, Tartaro G. Influence of kinesiologic tape on post-operative swelling after orthognathic surgery. J Maxillofac Oral Surg 2016;15:52-8.
4van der Vlis M, Dentino KM, Vervloet B, Padwa BL. Postoperative swelling after orthognathic surgery: a prospective volumetric analysis. J Oral Maxillofac Surg 2014;72:2241-7.
5Phillips C, Blakey III G, Jaskolka M. Recovery after orthognathic surgery: short-term health-related quality of life outcomes. J Oral Maxillofac Surg 2008;66:2110-5.
6Markovic A, Todorovic L. Effectiveness of dexamethasone and low-power laser in minimizing oedema after third molar surgery: a clinical trial. Int J Oral Maxillofac Surg 2007;36:226-9.
7Spinelli G, Lazzeri D, Conti M, Agostini T, Mannelli G. Comparison of piezosurgery and traditional saw in bimaxillary orthognathic surgery. J Cranio-Maxillofac Surg 2014;42:1211-20.
8Tachmatzidis T, Dabarakis N. Technology of lasers and their applications in oral surgery: literature review. Balkan J Dent Med 2016;20:131-7.
9Kim YD, Kim SS, Hwang DS, Kim SG, Kwon YH, Shin SH et al. Effect of low‐level laser treatment after installation of dental titanium implant‐immunohistochemical study of RANKL, RANK, OPG: an experimental study in rats. Lasers Surg Med 2007;39:441-50.
10Huang Y-Y., Chen AC-H., Carroll JD, Hamblin MR. Biphasic dose response in low level light therapy. Dose Response 2009;7:358-83.
11Peplow PV, Chung T-Y., Ryan B, Baxter GD. Laser photobiomodulation of gene expression and release of growth factors and cytokines from cells in culture: a review of human and animal studies. Photomed Laser Surg 2011;29:285-304.
12Bjordal JM, Johnson MI, Iversen V, Aimbire F, Lopes-Martins RAB. Low-level laser therapy in acute pain: a systematic review of possible mechanisms of action and clinical effects in randomized placebo-controlled trials. Photomed Laser Ther 2006;24:158-68.
13Walsh L. The current status of laser applications in dentistry. Aus Dent J 2003;48:146-55.
14Chow RT, Johnson MI, Lopes-Martins RA, Bjordal JM. Efficacy of low-level laser therapy in the management of neck pain: a systematic review and meta-analysis of randomised placebo or active-treatment controlled trials. Lancet 2009;374:1897-908.
15Hendudari F, Piryaei A, Hassani S-N., Darbandi H, Bayat M. Combined effects of low-level laser therapy and human bone marrow mesenchymal stem cell conditioned medium on viability of human dermal fibroblasts cultured in a high-glucose medium. Lasers Med Sci 2016;31:749-57.
16Petri AD, Teixeira LN, Crippa GE, Beloti MM, Oliveira PTd, Rosa AL. Effects of low-level laser therapy on human osteoblastic cells grown on titanium. Braz Dent J 2010;21:491-8.
17Szezerbaty SKF, de Oliveira RF, Pires-Oliveira DAA, Soares CP, Sartori D, Poli-Frederico RC. The effect of low-level laser therapy (660 nm) on the gene expression involved in tissue repair. Lasers Med Sci 2018;33:315-21.
18Lim H-M., Lew KK, Tay DK. A clinical investigation of the efficacy of low level laser therapy in reducing orthodontic postadjustment pain. Am J Orthod Dentofac Orthop 1995;108:614-22.
19Turhani D, Scheriau M, Kapral D, Benesch T, Jonke E, Bantleon HP. Pain relief by single low-level laser irradiation in orthodontic patients undergoing fixed appliance therapy. Am J Orthod Dentofac Orthop 2006;130:371-7.
20Youssef M, Ashkar S, Hamade E, Gutknecht N, Lampert F, Mir M. The effect of low-level laser therapy during orthodontic movement: a preliminary study. Lasers Med Sci 2008;23:27-33.
21Tortamano A, Lenzi DC, Haddad ACSS, Bottino MC, Dominguez GC, Vigorito JW. Low-level laser therapy for pain caused by placement of the first orthodontic archwire: a randomized clinical trial. Am J Orthod Dentofac Orthop 2009;136:662-7.
22Khadra M. The effect of low level laser irradiation on implant-tissue interaction. In vivo and in vitro studies. Swed Dent J Suppl 2005;(172):1-63.
23Jakse N, Payer M, Tangl S, Berghold A, Kirmeier R, Lorenzoni M. Influence of low‐level laser treatment on bone regeneration and osseointegration of dental implants following sinus augmentation: an experimental study on sheep. Clin Oral Implants Res 2007;18:517-24.
24Dostalova T, Kroulikova V, Podzimek S, Jelinková H. Low-level laser therapy after wisdom teeth surgery: evaluation of immunologic markers (secretory immunoglobulin A and lysozyme levels) and thermographic examination: placebo controlled study. Photomed Laser Surg 2017;35:616-21.
25Fernando S, Hill C, Walker R. A randomised double blind comparative study of low level laser therapy following surgical extraction of lower third molar teeth. Br J Oral Maxillofac Surg 1993;31:170-2.
26Kreisler M, Al Haj H, Noroozi N, Willershausen B, d’Hoedt B. Efficacy of low level laser therapy in reducing postoperative pain after endodontic surgery − a randomized double blind clinical study. Int J Oral Maxillofac Surg 2004;33:38-41.
27Gerschman J, Ruben J, Gebart‐Eaglemont J. Low level laser therapy for dentinal tooth hypersensitivity. Aus Dent J 1994;39:353-7.
28Gasperini G, de Siqueira IR, Costa LR. Does low-level laser therapy decrease swelling and pain resulting from orthognathic surgery? Int J Oral Maxillofac Surg 2014;43:868-73.
29Pocock SJ. Clinical Trials: A Practical Approach. New York: John Wiley & Sons; 2013.
30Carrillo J, Calatayud J, Manso F, Barberia E, Martinez J, Donado M. A randomized double-blind clinical trial on the effectiveness of helium-neon laser in the prevention of pain, swelling and trismus after removal of impacted third molars. Int Dent J 1990;40:31-6.
31Price DD, McGrath PA, Rafii A, Buckingham B. The validation of visual analogue scales as ratio scale measures for chronic and experimental pain. Pain 1983;17:45-56.
32Ozcelik O, Cenk Haytac M, Kunin A, Seydaoglu G. Improved wound healing by low‐level laser irradiation after gingivectomy operations: a controlled clinical pilot study. J Clin Periodontol 2008;35:250-4.
33Wagner VP, Curra M, Webber LP, Nör C, Matte U, Meurer L et al. Photobiomodulation regulates cytokine release and new blood vessel formation during oral wound healing in rats. Lasers Med Sci 2016;31:665-71.
34Albertini R, Villaverde A, Aimbire F, Salgado M, Bjordal J, Alves L et al. Anti-inflammatory effects of low-level laser therapy (LLLT) with two different red wavelengths (660 nm and 684 nm) in carrageenan-induced rat paw edema. J Photochem Photobiol B Biol 2007;89:50-5.
35Paschoal MAB, Santos-Pinto L. Therapeutic effects of low-level laser therapy after premolar extraction in adolescents: a randomized double-blind clinical trial. Photomed Laser Surg 2012;30:559-64.
36Fabre HS, Navarro RL, Oltramari-Navarro PV, Oliveira RF, Pires-Oliveira DA, Andraus RA et al. Anti-inflammatory and analgesic effects of low-level laser therapy on the postoperative healing process. J Phys Ther Sci 2015;27:1645-8.
37Roynesdal A, Björnland T, Barkvoll P, Haanaes H. The effect of soft-laser application on postoperative pain and swelling: a double-blind, crossover study. Int J Oral Maxillofac Surg 1993;22:242-5.
38D’ávila RP, Espinola LVP, de Freitas PM, Silva AC, Landes C, Luz JGC. Longitudinal evaluation of the effects of low-power laser phototherapy on mandibular movements, pain, and edema after orthognathic surgery.J Craniomaxillofac Surg 2019;47:758-65.