Effects of ibuprofen and low-level laser therapy on orthodontic pain by means of the analysis of interleukin 1-beta and substance P levels in the gingival crevicular fluid

Nociceptor mechanisms underlying pain and bone remodeling via orthodontic forces: toward no pain, big gain

Orthodontic forces are strongly associated with pain, the primary complaint among patients wearing orthodontic braces. Compared to other side effects of orthodontic treatment, orthodontic pain is often overlooked, with limited clinical management. Orthodontic forces lead to inflammatory responses in the periodontium, which triggers bone remodeling and eventually induces tooth movement. Mechanical forces and subsequent inflammation in the periodontium activate and sensitize periodontal nociceptors and produce orthodontic pain. Nociceptive afferents expressing transient receptor potential vanilloid subtype 1 (TRPV1) play central roles in transducing nociceptive signals, leading to transcriptional changes in the trigeminal ganglia. Nociceptive molecules, such as TRPV1, transient receptor potential ankyrin subtype 1, acid-sensing ion channel 3, and the P2X3 receptor, are believed to mediate orthodontic pain. Neuropeptides such as calcitonin gene-related peptides and substance P can also regulate orthodontic pain. While periodontal nociceptors transmit nociceptive signals to the brain, they are also known to modulate alveolar bone remodeling in periodontitis. Therefore, periodontal nociceptors and nociceptive molecules may contribute to the modulation of orthodontic tooth movement, which currently remains undetermined. Future studies are needed to better understand the fundamental mechanisms underlying neuroskeletal interactions in orthodontics to improve orthodontic treatment by developing novel methods to reduce pain and accelerate orthodontic tooth movement-thereby achieving "big gains with no pain" in clinical orthodontics.

The effectiveness of low-level laser therapy and low-intensity pulsed ultrasound in reducing pain induced by orthodontic separation: a randomized controlled trial

BACKGROUND

The low-level laser therapy (LLLT) and low-intensity pulsed ultrasound (LIPUS) have been recently applied to control pain during orthodontic treatment.

OBJECTIVE

To evaluate and compare the effectiveness of LLLT and LIPUS in reducing pain induced by orthodontic separation.

STUDY DESIGN

A single-blinded randomized controlled trial.

METHODS

One hundred and fifty patients were randomly assigned into three groups; LLLT group, LIPUS group, and control group. After 5 min from the separators' placement, the first dose of the laser or the ultrasound was applied, the second dose was applied after 24 h, and the third dose was applied after 48 h on both maxillary and mandibular first molars. The exposure of laser was for 20 s at each point (maxillary and mandibular first molars), with an 810-nm aluminum-gallium-arsenide (AlGaAs) diode laser on continuous mode. The output power set at 150 mW, the energy density of 4 J/cm2, and a laser spot diameter of 7 mm were applied. Whereas the frequency of ultrasonic toothbrush was 1.6 MHz; and average output intensity was 0.2 W/cm2. The application was for 20 min (5 min on each first molar). The control group received the separators without another intervention. A Visual Analog Scale (VAS 100 mm) was used to assess pain intensity at several time intervals during the first four days after the separators' placement.

RESULTS

A total of 145 patients were assessed. There was a significant difference in pain perception among the three groups after 5 min (P = .002). The maximum pain level was reached after 24 h. However, the laser group and the ultrasound group showed a statistically significant decrease in pain scores compared to the control group at all the assessment time points (P < .001). Whereas there was no difference between the laser group and the ultrasound group in reducing the pain scores (P > .05).

CONCLUSIONS

The LLLT and the LIPUS effectively reduce the separation pain when applied in multiple doses without differences between them.

TRIAL REGISTRATION

This trial was registered with the German Clinical Trials Register (DRKS). ( https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID= DRKS00029991). Date of registration: 26/08/2022.

The effectiveness of interventions in reducing pain related to orthodontic separation: a systematic review and meta-analysis

BACKGROUND

Pain is an unpleasant experience and annoying sensation. To control this pain during orthodontic separation, different pharmacological and non-pharmacological methods have been used.

OBJECTIVE

This systematic review and meta-analysis aimed to critically assess the evidence of the effectiveness of pharmacological and non-pharmacological methods in reducing pain induced by orthodontic separation.

SEARCH STRATEGY

An electronic search was conducted using the following databases: PubMed® (Medline), Scopus®, EMBASE®, Web of ScienceTM, Google ScholarTM, ProQuest, and Cochrane Central Register of controlled trials (CENTRAL) searching for the studies published between January 2012 and April 2023.

SELECTION CRITERIA

Only randomized controlled trials (RCTs) were included, each experimental group included patients who received elastomeric separators and one kind of pharmacological or non-pharmacological interventions for pain reduction during the separation stage.

DATA COLLECTION AND ANALYSIS

Cochrane's risk of bias tool (RoB2 tool) was applied. The Grading of Recommendations Assessment, Development, and Evaluation [GRADE] approach was used to evaluate the strength of the evidence.

RESULTS

Thirty-one studies (RCTs) were included in this systematic review. Nineteen of them were appropriate for quantitative synthesis and used VAS for pain assessment. Meta-analysis showed that low-level laser therapy (LLLT) was an effective approach for pain relief after separators placement with standard mean difference of 13.79 mm (95% confidence interval (CI): -15.64, -11.94) at 6 h and 23.34 mm at 24 h (95% CI: -25.91, -20.77). LLLT was also effective when applied in split-mouth and the standard mean difference was 8.9 mm at 6 h (95% CI: -12.86, -3.33) and 17.15 mm at 24 h (95% CI: -30.12, -4.17). Ibuprofen had a pain control effect at 6 h and at 24 h compared with the placebo group. The standard mean difference was 14.37 mm (95% CI: -20.54, -8.19) and 20.46 mm (95% CI: -27.79, -13.13), respectively. There was no difference in pain control between ibuprofen and acetaminophen. Naproxen had lower visual analog scale scores in pain perception at 6 h and the standard mean difference was 7.03 mm (95% CI: -12.67, -1.40).

CONCLUSIONS

The application of LLLT decreased the pain induced by the separation during the first day of teeth separation; the pain reduction showed an increase from 6 h to the end of the 24 h. However, the evidence is weak to moderate. The analgesics reduced the pain compared to placebo; this pain reduction had shown an increase from 6 h to the end of the 24 h. The strength of the evidence is moderate. Naproxen gel effectively reduced the pain compared to placebo; the evidence in this regard is moderate. Naproxen gel effectively reduced the pain compared to placebo, but it was less effective than the oral intake of non-steroidal anti-inflammatory drugs. However, the evidence in this regard is moderate.

REGISTRATION

This systematic review was registered with PROSPERO (CRD42022335553) during the first stages of its conduction.

Orthodontic Patients with Poor Oral Health-Related Quality of Life are More Likely to Have Emotional Distress: A Cross-Sectional Study

Objective

This study aims to investigate the relationship between oral health-related quality of life (OHRQoL) and emotional distress (ED), including anxiety and depression, in orthodontic patients.

Methods

A cross-sectional study was conducted involving 603 orthodontic patients, consisting of 401 females (66.5%) with a mean age of 24.15 ± 7.72 and 202 males (33.5%) with a mean age of 24.16 ± 7.72. A questionnaire containing questions of demographic information, the Oral Health Impact Profile (OHIP-14) and the Huaxi emotional-distress index (HEI) was employed to assess OHRQoL and ED. According to the HEI score, the respondents were divided into ED group (HEI > 8) and non-ED group (HEI ≤ 8). Data were analyzed using Kolmogorov-Smirnov test, Mann-Whitney test and logistic regression analysis with the significance level set at p < 0.05.

Results

The prevalence of poor OHRQoL and ED of the study sample was 28.4% and 19.57%, respectively. There was a significantly higher prevalence of ED among poor OHRQoL patients (35.67%) compared to those with good OHRQoL (13.19%) (p < 0.001). Poor OHRQoL and risky drinking behavior addressed higher significant correlation with ED patients than non-ED patients (p < 0.05). There were no statistical differences in other factors such as gender, age, and appliance type (p > 0.05). Poor OHRQoL orthodontic patients were at a higher risk of suffering from anxiety and depression compared to those with good OHRQoL (age-risky drinking behavior-sex-adjusted: OR = 4.00; all p < 0.001).

Conclusion

Oral health-related quality of life (OHRQoL) is related to emotional stress. Namely, patients with poor OHRQoL are more likely to experience anxiety and depression. As a result, orthodontists should consistently assess the emotional well-being and OHROoL of patients over the treatment course for better treatment outcomes.

The Effects and Mechanisms of PBM Therapy in Accelerating Orthodontic Tooth Movement

Malocclusion is one of the three major diseases, the incidence of which could reach 56% of the imperiled oral and systemic health in the world today. Orthodontics is still the primary method to solve the problem. However, it is clear that many orthodontic complications are associated with courses of long-term therapy. Photobiomodulation (PBM) therapy could be used as a popular way to shorten the course of orthodontic treatment by nearly 26% to 40%. In this review, the efficacy in cells and animals, mechanisms, relevant cytokines and signaling, clinical trials and applications, and the future developments of PBM therapy in orthodontics were evaluated to demonstrate its validity. Simultaneously, based on orthodontic mechanisms and present findings, the mechanisms of acceleration of orthodontic tooth movement (OTM) caused by PBM therapy were explored in relation to four aspects, including blood vessels, inflammatory response, collagen and fibers, and mineralized tissues. Also, the cooperative effects and clinical translation of PBM therapy in orthodontics have been explored in a growing numbers of studies. Up to now, PBM therapy has been gaining popularity for its non-invasive nature, easy operation, and painless procedures. However, the validity and exact mechanism of PBM therapy as an adjuvant treatment in orthodontics have not been fully elucidated. Therefore, this review summarizes the efficacy of PBM therapy on the acceleration of OTM comprehensively from various aspects and was designed to provide an evidence-based platform for the research and development of light-related orthodontic tooth movement acceleration devices.

Evaluation of periodontal parameters and gingival crevicular fluid cytokines in children with anterior open bite receiving passive orthodontic treatment with a spur

Objective

To evaluate clinical parameters and gingival crevicular fluid (GCF) cytokines in children with anterior open bite receiving passive orthodontic treatment with spurs.

Methods

Twenty children with indications for interceptive orthodontic treatment, an anterior open bite, and good oral hygiene and periodontal health were included in this study. GCF samples were collected from the mandibular and maxillary central incisors before (baseline) and 24 hours and 7 days after spur bonding. Clinical and periodontal examinations and cytokine analyses were performed.

Results

At 7 days after spur attachment, gingival bleeding in the mandibular group was increased relative to that in the maxillary group. Visible plaque was correlated with gingival bleeding at 7 days and the GCF volume at 24 hours after spur attachment. Compared with those at baseline, interleukin (IL)-8 levels in the maxillary group and IL-1β levels in both tooth groups increased at both 24 hours and 7 days and at 7 days, respectively. At 24 hours, IL-8, IL-1β, and IL-6 levels were higher in the maxillary group than in the mandibular group. Cytokine production was positively correlated with increased GCF volume, but not with gingival bleeding, visible plaque, or probing depth.

Conclusions

Although orthodontic treatment with spurs in children resulted in increased gingival bleeding around the mandibular incisors, IL levels were higher around the maxillary incisors and not correlated with periodontal parameters. Increased cytokine levels in GCF may be associated with the initial tooth movement during open bite correction with a passive orthodontic appliance in children.

Open bite

Molecular mechanism in trigeminal nerve and treatment methods related to orthodontic pain

BACKGROUND

Orthodontic treatment is the main treatment approach for malocclusion. Orthodontic pain is an inevitable undesirable adverse reaction during orthodontic treatment. It is reported orthodontic pain has become one of the most common reason that patients withdraw from orthodontic treatment. Therefore, understanding the underlying mechanism and finding treatment of orthodontic pain are in urgent need.

AIMS

This article aims to sort out the mechanisms and treatments of orthodontic pain, hoping to provide some ideas for future orthodontic pain relief.

MATERIALS

Tooth movement will cause local inflammation. Certain inflammatory factors and cytokines stimulating the trigeminal nerve and further generating pain perception, as well as drugs and molecular targeted therapy blocking nerve conduction pathways, will be reviewed in this article.

METHOD

We review and summaries current studies related to molecular mechanisms and treatment approaches in orthodontic pain control.

RESULTS

Orthodontics pain related influencing factors and molecular mechanisms has been introduced. Commonly used clinical methods in orthodontic pain control has been evaluated.

DISCUSSION

With the clarification of more molecular mechanisms, the direction of orthodontic pain treatment will shift to targeted drugs.