Efficacy of Photobiomodulation Therapy for Orthodontic Pain Control Following the Placement of Elastomeric Separators: A Randomized Clinical Trial

Introduction: Controlling pain in orthodontic patients has gained special attention. This study assessed the efficacy of photobiomodulation therapy (PBMT) for pain control following the placement of elastomeric separators.Methods: This split-mouth single-blind randomized clinical trial evaluated 30 orthodontic patients who required posterior elastomeric separators. The two maxillary quadrants were randomized into the laser and control groups. In the laser quadrant, an 808 nm diode laser (400 mW, 15.60 J/cm2,11 seconds, continuous-wave, contact mode) was irradiated to the cervical third of the maxillary first molar roots 24 hours prior to the placement of separators. The control quadrant received placebo radiation by a light-curing unit. The patients received the second laser cycle right before the placement of separators 24 hours later. The level of self-perceived pain was recorded at 0, 2, 6, 24, and 72 hours and 5 days after the intervention in the laser and control quadrants using a visual analog scale (VAS). Data were analyzed using the analysis of variance (ANOVA) and paired-samples t-test.Results: The trend of change in the pain score was similar in both groups. The pain score was significantly lower in the laser group than the control group at all-time points (P<0.05) except at time 0. The pain score increased in the first 6 hours and reached its maximum level in 24 hours in both groups.Conclusion: PBMT by an 808 nm diode laser can effectively decrease pain following the placement of elastomeric separators DOI:10.34172/jlms.2021.0

Release of nickel and chromium ions from orthodontic wires following the use of teeth whitening mouthwashes

Abstract Background Corrosion resistance is an important requirement for orthodontic appliances. Nickel and chromium may be released from orthodontic wires and can cause allergic reactions and cytotoxicity when patients use various mouthwashes to whiten their teeth. Our study aimed to assess the release of nickel and chromium ions from nickel titanium (NiTi) and stainless steel (SS) orthodontic wires following the use of four common mouthwashes available on the market. Methods This in vitro, experimental study was conducted on 120 orthodontic appliances for one maxillary quadrant including five brackets, one band and half of the required length of SS, and NiTi wires. The samples were immersed in Oral B, Oral B 3D White Luxe, Listerine, and Listerine Advance White for 1, 6, 24, and 168 h. The samples immersed in distilled water served as the control group. Atomic absorption spectroscopy served to quantify the amount of released ions. Results Nickel ions were released from both wires at all time-points; the highest amount was in Listerine and the lowest in Oral B mouthwashes. The remaining two solutions were in-between this range. The process of release of chromium from the SS wire was the same as that of nickel. However, the release trend in NiTi wires was not uniform. Conclusions Listerine caused the highest release of ions. Listerine Advance White, Oral B 3D White Luxe, and distilled water were the same in terms of ion release. Oral B showed the lowest amount of ion release

Ectopic eruption: Management of a partial mandibular lateral incisor transposition in a case report

Introduction: tooth transposition is a rare condition especially in the mandibular arch. Management of this condition is so hard, complicated and unknown for most of the clinicians. Case report: In this report we describe a case of orthodontic management of a partial mandibular left lateral incisor and canine transposition. We used a modified lingual arch appliance for initial correction of tooth transposition, more detailing was achieved by fix treatment. Discussion: Early detection of this anomaly is very important. Providing panoramic radiography to assess the developing dentition during the age of 6 to 8 years is an apropos forethought

Effect of Bone Borne Expansion and Tooth Borne Palatal Expansion on Airway Volume: A Review Article

Background and purpose: Transverse problems in the maxilla (high arched- narrow hard plates) can cause respiratory disorders. Palatal expansion can be helpful in this way. The present study aimed at evaluating the effect of bone borne expansion and tooth borne palatal expansion on airway volume. Materials and methods: A review study was performed by search in Google Scholar, Scopus, PubMed, Embase, and Cochrane using the following keywords: maxillary expansion, palatal expansion, miniscrew-assisted palatal expansion, tooth borne, bone borne, rapid palatal expansion, airway dimension, and Cone beam computed tomography. The search was limited to articles published in January 2011-April 2021. Results: In the initial search, 343 articles were found. After reviewing the titles and abstracts only 20 papers were found that studied the effect of bone and tooth borne palatal expansion on airway dimensions and met the inclusion criteria. The studies indicated that both bone expansion and tooth borne palatal expansion could considerably increase airway volumes. However, only bone borne palatal expansion enabled more predictable and greater skeletal expansion and less teeth response. Conclusion: Both bone and tooth borne palatal expansion are efficient in increasing the airway volume. Further randomized clinical trials with large sample size and matched control groups, longer follow-up periods and measuring respiration index such as apnea-hypopnea index are suggested

Influence of medication on the rate of orthodontic tooth movement (Part 1: hormons and corticosteroids)

The aim of this review article was to define the mechanism of action and effects of commonly used medications on the tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and medline (1980-2013). 63 articles were included in this review. 34 of them were related to the effects of hormones and analgesics, were evaluated in this article but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Non Steroidal Anti-Inflammatory Drugs (NSAIDs) reduced the rate of tooth movement while non-NSAIDs such as acetaminophen had no effect on the rate of OTM. Corticosteroids, parathyroid hormone and thyroxin increased the rate of tooth movement. Sturgeons might slow OTM, but experimental studies are lacking. Medications might have an important influence on the rate of tooth movement and information on their consumption is necessary to adequately discuss treatment planning with patients

Evaluation of the Effect of Phosphoric Acid or Er: YAG Laser on the Shear Bond Strength of Orthodontic Brackets to Enamel Surfaces Followed by 980-Laser Assisted Bleaching: An In Vitro Study: Er: YAG laser on shear strength of brackets to bleached enamel

Introduction: The residual oxygen remaining on the tooth surface after bleaching may interfere with the adhesion of brackets to the enamel surface. This study aimed to evaluate the influence of phosphoric acid and Er: YAG laser as an etching technique on the shear bond strength (SBS) of orthodontic brackets to enamel surfaces after 980-laser-assisted bleaching.Method: A total of 84 human premolars were recruited in the present study. Samples were divided into 6 groups including conventional bleaching with conventional etching, conventional bleaching with Er: YAG laser etching, laser-assisted bleaching with conventional etching, and Laser-assisted bleaching with Er: YAG laser etching, without bleaching with traditional etching, and without bleaching+Er: YAG laser etching. Following thermocycling, the debonding of brackets was conducted using a universal testing machine. Scanning electron microscope (SEM) microscope evaluation and adhesive remnant index (ARI) scores were assessed. The comparison of SBS values between groups was carried out through a one-way analysis of variance, followed by post hoc tests.Results: The non-bleaching with conventional etching group showed the highest SBS mean value (23.45±5.16 MPa), whereas the conventional bleaching with conventional etching group represented the lowest SBS mean value (8.8±3.83 MPa). In all groups, the most common type of failure was classified as either score 1 or score 2. No significant difference was observed in terms of SBS mean between the groups (P=0.165); however, the average SBS of bleached teeth was significantly lower, compared to the non-bleached group (P=0.000). Honeycomb structure and porosity were observed following Er: YAG laser etching on the tooth surface.Conclusion: Increased bond strength of brackets was observed in bleached teeth following Er: YAG laser etching. Therefore, if necessary, bonding the brackets on the same day of bleaching will be done, and the application of Er: YAG laser as an etching technique will be recommended

Treatment of Skeletal Anterior Open Bite Using Absolute Anchorage: A Case Report and Review

Background and purpose: Skeletal anchorage is a new aid for the correction of moderate anterior open bite. This study aimed at treating moderate anterior open bite using posterior intrusion via mini implants. In addition, a review of studies carried out on open bite correction using absolute anchorage was performed. Materials and methods: The following keywords were used: open bite, camouflage, extraction, surgery, bone-anchor intrusion, posterior intrusion, mini screw, mini plate, and absolute anchorage. A review of articles was performed in PubMed, Embase, Google Scholar, and Cochrane. The time span of article search was from January 2011 to April 2021. In the case presented in this study, an anterior open bite was corrected with mini implants. Results: Twelve studies were selected from 42 articles that met the initial eligibility criteria.  In most studies, the reduction in mandibular plane angle (SN-GoGn and FMA) was less than 2◦ following counterclockwise rotation. But, in some studies the changes ranged between 2.3 and 3.9◦. In all studies following mandibular autorotation, facial convexity decreased, chin contour improved, and lower anterior face height decreased. Our patient also showed a decrease of 2° in the mandibular plane angle and a decrease of 1°in facial convexity. Conclusion: According to this study, intrusion of posterior teeth with the aid of moderate skeletal anchorage is a non-invasive camouflage treatment. Also, in the patient studied here it corrected overbite, improved facial appearance, and reduced the need for surgery

The effect of medication on the rate of orthodontic tooth movement (Part 2: Mediators and other drugs)

Molecules produced in various diseased tissues or drugs and nutrients consumed regularly by patients, can reach the mechanically stressed paradental tissues through the circulation and interact with local target cells. The combined effect of mechanical forces and one or more of these agents may be inhibitory, additive or synergistic. The aim of this review was to outline the mechanisms of action and effects of some commonly used drugs on tissue remodeling and Orthodontic Tooth Movement (OTM). A review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed using Cochrane library, Embase and Medline (1980-2013). 63 articles were included in the review. 34 of them related to the effects of hormones and analgesics were evaluated in the first part of this review. The rest of them (29 articles) were evaluated in the current review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement and medication regimens. Vitamin D3 might enhance the pace of tooth movement, but dietary calcium and fluorides appear to reduce the rate of OTM. Bisphosphonates (BPNs) are considered to have marked inhibitory effects on the rate of tooth movement. Nicotine and nitric oxide might effectively increase the speed of OTM. All drugs reviewed had therapeutic effects, as well as side effects, that may influence the cells targeted by orthodontic forces. Therefore, it is imperative that the orthodontist pays close attention to the drug consumption history of each and every patient, before and during the course of orthodontic treatment. When the use of drugs is revealed, their effects and side effects on tissue systems should be explored to determine their potential influence on the outcome of mechanotherapy

Shear Bond Strength of Rebonded Ceramic Brackets Using Four Different Methods of Adhesive Removal

Objectives: Rebonding of isolated brackets is an economic option that can be conducted using available in-office or commercial recycling methods. Nowadays, lasers are known as an efficient modality for composite removal, but there is not much information available about using lasers for removal of adhesive remnants from the ceramic bracket base. Materials and Methods: Fifty human premolar teeth were divided into five groups. Samples in all groups were bonded to ceramic brackets. Brackets in four groups were debonded and the remaining adhesive was removed by Er:YAG laser, Er;Cr:YSGG laser, sandblasting or direct flame. After removing adhesives from the tooth surfaces by carbide bur, the recycled brackets were bonded again. in the control group, new ceramic brackets were bonded.  Finally, all brackets were debonded by universal testing machine and their shear bond strength (SBS) was measured. The adhesive remnant index (ARI) was calculated under a stereomicroscope at x10 magnification. Data were analyzed using one-way ANOVA and Tukey’s test. Results: SRS values showed no significant difference among the five groups (P=0.568). The highest SRS was noted in the control group (7.46±1.4 MPa), followed by Er:YAG laser group (7.40±1.24 Mpa) and the lowest was noted in the flame group (6.32±2.3 Mpa). ARI scores indicated that most of the adhesive remained on the tooth surface in all groups Conclusions: Recycling of ceramic brackets with Er:YAG laser is an efficient in-office method which causes the least damage to the bracket base. However, all methods of bracket recycling showed acceptable SBS

Effect of Surface Treatment on Enamel Cracks after Orthodontic Bracket Debonding: Er,Cr:YSGG Laser-Etching versus Acid-Etching

Objectives: This study sought to compare enamel cracks after orthodontic bracket debonding in the surfaces prepared with erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser and the conventional acid-etching technique. Materials and Methods: This in-vitro experimental study was conducted on 60 sound human premolars extracted for orthodontic purposes. The teeth were randomly divided into two groups (n=30). The teeth in group A were etched with 37% phosphoric acid gel, while the teeth in group B were subjected to Er,Cr:YSGG laser irradiation (gold handpiece, MZ8 tip, 50Hz, 4.5W, 60µs, 80% water and 60% air). Orthodontic brackets were bonded to the enamel surfaces and were then debonded in both groups. The samples were inspected under a stereomicroscope at ×38 magnification to assess the number and length of enamel cracks before bonding and after debonding. Independent-samples t-test was used to compare the frequency of enamel cracks in the two groups. Levene’s test was applied to assess the equality of variances. Results: No significant difference was noted in the frequency or length of enamel cracks between the two groups after debonding (P>0.05). Conclusions: Despite the same results of the frequency and length of enamel cracks in the two groups and by considering the side effects of acid-etching (demineralization and formation of white spot lesions), Er,Cr:YSGG laser may be used as an alternative to acid-etching for enamel surface preparation prior to bracket bonding.