Does the use of low-level light therapy postoperatively reduce pain, oedema, and neurosensory disorders following orthognathic surgery? A systematic review

Therapeutic modalities for iatrogenic late paresthesia in oral tissues innervated by mandibular branch of trigeminal nerve: a systematic review

BACKGROUND

The present systematic review intended to evaluate the current evidence on the modalities used for treating iatrogenic late paresthesia in the oral tissues innervated by the mandibular branch of the trigeminal nerve.

MAIN TEXT

As a common side effect of dental procedures, paresthesia can exert a profound adverse effect on patients' quality of life. The inferior alveolar nerve (IAN) and lingual nerve (LN) have the highest chance of injury during several dental procedures, including mandibular orthognathic surgeries, implant placement, extraction of the third molar, anesthetic injections, flap elevation, and endodontic treatments. Moreover, several methods have been proposed for treating iatrogenic late paresthesia, including photobiomodulation (PBM), microsurgery, medication, and close observation until achieving spontaneous recovery of sensation. However, no gold standard treatment for iatrogenic paresthesia has been agreed upon up to now. The present study included a comprehensive search of the databases of PubMed, Embase, Scopus, and Web of Science up to December 04, 2023, resulting in a total of 3122 related studies. Then, the titles, abstracts, and full texts of the studies were evaluated. Ultimately, seven controlled randomized trials (RCTs) were included in the final analysis. Also, the risk of bias was assessed using the Joanna Briggs Institute (JBI) critical appraisal checklist. Among all fields, randomization, allocation concealment, and data analysis were found to have the highest chance of bias in the included studies.

CONCLUSIONS

In conclusion, PBM, vitamin B12, and corticosteroids could accelerate the recovery of late paresthesia. However, considering the low sample size of the included studies and the high risk of methodological bias, it is recommended to perform further RCTs with robust study designs following Good Clinical Practice (GCP) guidelines to achieve more reliable results.

The Effect of Delayed Photobiomodulation Therapy on Inferior Alveolar Nerve Recovery After Third Molar Removal: A Triple-Blinded Randomized Clinical Trial

Background: Third molar removal is the primary reason for inferior alveolar nerve (IAN) damage, with 2% causing persistent neurosensory deficits. This study aimed to investigate how delayed photobiomodulation therapy affects long-lasting neurosensory disturbances. Methods: This study was conducted on patients with neurosensory disturbances lasting longer than 6 months. Patients were randomly allocated to the study and control groups, with the study group receiving a low-power diode laser (continuous wavelength of 810 nm, power of 200 mW) on 16 points (30 sec at each) for 12 sessions (2 sessions/week), while the control group received a placebo treatment by switched-off laser probe. Visual analog scale (VAS; ranging from 1 to 5), static light touch, two-point discrimination, direction discrimination, pinprick, and thermal discrimination tests were performed on each visit up to 9 months post-therapy to evaluate the recovery status. Results: Each group comprised 18 participants. The mean time since injury was 8.26 ± 2.05 and 8.38 ± 1.98 months for the control and intervention groups, respectively (p = 0.81). There was a significant improvement in the intervention group on the static light touch (p = 0.041), two-point discrimination (p = 0.028), VAS (p = 0.031), and pinprick (p = 0.014) tests on the 11th session and subsequent visits and also on direction discrimination test on the 12th session (p = 0.044) and after that. There was no significant difference in the thermal discrimination tests between the two groups (p > 0.05). Conclusion: Photobiomodulation demonstrated potential benefits in resolving persistent neurosensory deficits of the IAN, with noticeable improvements typically observed after around 35 days of treatment initiation (10 sessions).

Photobiomodulation Therapy in the Management of Late Complications After Facial Filling

The aim of the present study is to report a clinical case of a patient diagnosed with a late adverse reaction to the injection of filler material - persistent and intermittent delayed swelling (PIDS) - in which photobiomodulation therapy (PBMT) with low-power laser was used for edema reduction. This is an observational, descriptive, and retrospective work of a case report. The female patient, aged 73 years old, had undergone dermal filler six years before and complained of increased volume in the face region (glabellar region, labiomental sulcus, and nasolabial folds) and was submitted to ultrasound and anatomopathological analysis. PBMT using a low-power laser (660 nm and 808 nm, simultaneous irradiation, in contact, 2 J/point, 100 mW) proved to be effective for the non-invasive approach of late adverse reaction to dermal filler, such as PIDS, a common complication related to the use of dermal fillers.

Exploring the relationship between the number of systematic reviews and quality of evidence: an orthognathic surgery-based study

OBJECTIVE

We analyzed the quality and quantity of systematic reviews (SRs) of orthognathic surgery, the most frequently published topic in maxillofacial surgery.

STUDY DESIGN

We searched the PubMed database for SRs of orthognathic surgery with no restriction on the language of publication date. We assessed the certainty of evidence presented according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol and the Leiden Manifesto using the Grading of Recommendations Assessment, Development, and Evaluation approach. We analyzed the data using descriptive statistics, Pearson´s correlation test, and linear regression.

RESULTS

Of the 171 SRs evaluated, approximately one fifth presented evidence with a high level of certainty. The number of orthognathic surgery SRs has been increasing, and many SRs were published after very similar topics had already been published. There is no relationship between the impact factor and the certainty of evidence.

CONCLUSIONS

An excessive number of SRs of orthognathic surgery are published, and many SRs are superfluous, simply reporting previous findings. Clinicians should not base treatment decisions solely on the evidence presented in SRs, and journal editors and reviewers should evaluate these SRs more critically, particularly when they address topics that have already been covered in the literature.

Effectiveness of low-intensity laser photobiomodulation in reducing inflammatory events (pain, edema, and trismus) after orthognathic surgery: a systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

This systematic review aimed to answer whether, in (P) individuals undergoing orthognathic surgery, (I) low-level laser therapy (LLLT) during or shortly after the surgical procedure compared to (C) pharmacologic therapy alone or no therapy for improvement of post-intervention complications relieves (O) postoperative inflammatory events in (S) randomized clinical trials.

MATERIAL AND METHODS

A preliminary electronic search was conducted for references with language following a Latin (Roman) alphabet in seven databases index, and gray literature without restriction on language or publication period. Risk of bias was performed by RoB 2.0 tool, and meta-analysis used mean differences (MD) for edema and mouth opening and standardized mean differences (SMD) for pain scores (p < 0.05, Revman®).

RESULTS

A total of 91 control patients and 114 LLLT patients were included. The wavelengths ranged from 660 to 940 nm, and the applied energy density was between 5 and 100 J/cm2 at mostly extraoral distributed points. LLLT significantly reduced edema (MD =  - 4.27, CI95% - 5.13 to - 3.41 mm) in the period from 5 days to 2 weeks postoperatively (p < 0.001) and showed strongly reduced pain scores (SMD =  - 1.37, I95% =  - 1.99 to - 0.75) between 1 day and 5 weeks (p < 0.001), without significantly interfering with mouth opening (p = 0.110). Despite the low risk of bias, high heterogeneity among studies (I2 > 70%) and small sample sizes made the certainty of GRADE evidence low.

CONCLUSION

This SR demonstrated that LLLT effectively controls pain and edema after orthognathic surgery.

CLINICAL RELEVANCE

Systematic review that summarizes the use of photobiomodulation on orthognathic surgery.

Nerve Injury and Photobiomodulation, a Promising Opportunity: A Scoping Review on Laser Assisted Protocols for Lesions in the Oral Region

The currently available therapeutic options for restoring function and sensitivity in long-term nervous injuries pose challenges. Microsurgery interventions for direct nerve repair often lead to serious complications and limited success. Non-surgical methods, although somewhat effective, have limited benefits. These methods involve drug administration, such as with analgesics or corticosteroids. Photobiomodulation therapy (PBMT) has emerged as a promising approach based on clinical and laboratory studies. PBMT stimulates the migration and proliferation of neuronal fiber cellular aggregates, as reported in the literature. Experimental studies on animal models with peripheral nerve compression injuries have shown that PBMT can enhance the functionality of damaged nerves, preserving their activity and preventing scar tissue formation. The mechanism of action depends on the wavelength, which can positively or negatively affect photo acceptor resonances, influencing their conformation and activities. These findings suggest that photobiomodulation may accelerate and improve nerve regeneration. This review explores various methodologies used in photobiomodulation for regenerating nerve sensitivity after surgical trauma involving nerve structures, in the oral and peri-oral region. Research was conducted to evaluate which laser-assisted therapeutic protocols are used to improve the recovery of nervous sensitivity, using the JBI methodology for scoping reviews and following the PRISMA methodology.

Use of infrared photobiomodulation with low-level laser therapy for reduction of bleaching-induced tooth sensitivity after in-office bleaching: a double-blind, randomized controlled trial

The purpose of this study is to evaluate the use of infrared photobiomodulation with low-level laser therapy (PBM) to reduce bleaching-induced tooth sensitivity (TS) after in-office bleaching. Eighty-three participants were randomized in blocks into two groups. In the experimental group, the patients received an application after each session of in-office bleaching (35% hydrogen peroxide, 1 × 50 min; 2 sessions with 1-week interval), while the laser application was simulated in the control group. The PBM system was operated in continuous mode, using 3 J of energy. A dose of 100 J/cm2 was applied for 30 s with 808 nm (100 mW of power) in the middle third of the crown. The risk and intensity of TS were recorded immediately after bleaching, 1 h, 24 h, and 48 h after each bleaching session, with a visual scale analog (0-10) and a five-point numerical scale (0-4). The color was recorded at the beginning, weekly, and 1 month after the end of the bleaching (VITA Classical, VITA Bleachedguide, and digital spectrophotometer). The risk of TS was 98% (95% CI 88 to 99%) for the laser group and 95% (95% CI 83 to 99%) for the control (RR = 1.03; 95% CI 0.94 to 1.12; p = 1.0). Similarly, no difference in the intensity of TS was detected for both pain scales (p > 0.65). Improvement in color change, regardless of the group, was observed (p > 0.15). The application of an PBM did not reduce the risk and intensity of TS when applied after the procedure using the parameters recommended by the manufacturer.Trial registration number and date of registration: RBR-4HCVSG-04/06/2019.

Recovery following Orthognathic Surgery Procedures-A Pilot Study

This study aims at evaluating and categorizing patients’ objective and subjective postoperative recovery symptoms after bimaxillary orthognathic surgery assigning the healing process. The patients were monitored throughout the recovery process, and their symptoms were managed. A prospective, observational study was performed. Patients with Class II and III malocclusion (aged 18 to 35) were evaluated and monitored preoperatively, and postoperatively at 48 h, 2 weeks, 1 month, and 3 months postsurgery. A questionnaire was used to assess pain and anesthesia/hypoesthesia. The most common objective and subjective signs that were correlated with the healing process were edema, hematoma, trismus, pain, and anesthesia/hypoesthesia. Edema peaked at 48−72 h postoperatively (distance between eye’s external canthus and gonion, mean difference = 4.53, between tragus and cheilion, mean difference = 7, between tragus and gnathion, mean difference = 4.65, p < 0.001); mouth opening amplitude was significantly decreased during the first two weeks postsurgery (class II, mean difference = 32.42, p = 0.006, class III, mean difference = 44.57, p < 0.001), but it steadily and considerably improved over three months. The nose tended to widen postsurgery. The most severe pain experienced by patients was of medium intensity in the mandibular body, described as pressure, and usually did not spread. Patients were most severely and persistently impacted by anesthesia/hypoesthesia.

Effect of delayed photobiomodulation therapy on neurosensory recovery in patients with mandibular nerve neurotmesis following traumatic mandibular fracture: A randomized triple-blinded clinical trial

INTRODUCTION

There is a possibility of neurotmesis of the inferior alveolar nerve (IAN) in mandibular fractures, which leads to neurosensory impairment. In this study, we aimed to investigate the efficacy of photobiomodulation therapy (PBMT) in patients with neurotmesis following trauma and mandibular fracture.

MATERIALS AND METHODS

This triple-blind randomized trial was carried out on patients who suffered neurotmesis of the IAN following mandibular angle and body fracture at least for 6 months. In the intervention group, laser irradiation was applied with a low-level GaAlAs diode laser (continuous wave of 810 nm wavelength, power of 200 mW, and energy density of 12-14 J/cm²). In the control group, the laser probe was turned off and placed on the affected area. LLLT was done for 12 sessions (2 times/week for 6 weeks). Light touch sensations, two-point discrimination, thermal discrimination (cold and warm stimulus), electric pulp test (EPT), and oral health impact profile (OHIP)-14 questionnaire were performed before the intervention, immediately after each PBMT session, and after 3, 6, 9 and 12 months.

RESULTS

In both groups, 3 and 23 patients were female and male, respectively. The results showed significantly improved light (cotton swab), light (wooden cotton swab), and sharp (dental needle) touch sensations, and two-point discrimination test in the PBMT group after the 10th, 11th, 10th, and 10th session, respectively. Two-way repeated measure ANOVA revealed that the trend of light touch sensation with cotton swab and two-point discrimination test was statistically significant (p-value = 0.002 and 0.001, respectively). The results of OHIP-14 test showed a significantly higher mean in the PBMT group 3 months after PBMT. There was no statistically significant difference in EPT and thermal discrimination tests regarding the patients' group.

CONCLUSION

PBMT could be an effective treatment for late post-traumatic nerve neurotmesis following a traumatic mandibular fracture.