[Effect of maxillary expansion combined with orofacial myofunctional therapy on the position of the tongue of children with mouth breathing].

Objective:This study aimed to investigate the change of the position of the tongue before and after combined treatment of maxillary expansion and orofacial myofunctional therapy in children with mouth-breathing and skeletal class Ⅱmalocclusion. Methods:A total of 30 children with skeletal class Ⅱ malocclusion and unobstructed upper airway were selected. The 30 children were divided into mouth-breathing group（n=15） and nasal-breathing group（n=15） and CBCT was taken. The images were measured by Invivo5 software. The measurement results of the tongue position of the two groups were analyzed by independent samples t-test. 15 mouth-breathing children with skeletal class Ⅱ malocclusion were selected for maxillary expansion and orofacial myofunctional therapy. CBCT was taken before and after treatment, the measurements were analyzed by paired sample t test with SPSS 27.0 software package. Results:The measurement of the tongue position of the mouth-breathing and nasal-breathing groups were compared, the differences were statistically significant（P<0.05）. The measurement of the tongue position showed significant difference after the combined treatment of maxillary expansion and orofacial myofunctional therapy in children with mouth-breathing and skeletal class Ⅱmalocclusion（P<0.05）. Conclusion:Skeletal class Ⅱ malocclusion children with mouth-breathing have low tongue posture. The combined treatment of maxillary expansion and orofacial myofunctional therapy can change the position of the tongue.

Influência da idade e do tempo de uso da Placa Palatina de Memória por crianças com Trissomia do 21 nas mudanças miofuncionais orofaciais percebidas pelos pais, na adaptação e satisfação da família após quatro meses de tratamento / nfluence of age and time of use of the Stimulating Palatal Plate by children with Trisomy 21 on orofacial myofunctional changes perceived by parents, children's adaptation, and family's satisfaction after four months of treatment / Influencia de la edad y el tiempo de uso de la placa de memoria palatina por niños con trisomía 21 sobre los cambios miofuncionales orofaciales percibidos por los padres, adaptación y satisfacción familiar después de cuatro meses de tratamiento

Objetivo: verificar se a idade das crianças com Trissomia do 21 e o tempo de uso por dia da placa palatina de memória influenciam a adaptação da criança à placa, as mudanças miofuncionais orofaciais percebidas pelos pais e a satisfação da família, após quatro meses de tratamento. Métodos: participaram do estudo14 pais ou responsáveis legais de crianças com Trissomia do 21, com idades de 3 a 20 meses. O tratamento com a placa palatina de memória foi realizado durante quatro meses. A adaptação da criança à placa, as mudanças miofuncionais orofaciais percebidas pelos pais e a satisfação das famílias em relação ao tratamento foram investigadas por meio de questionário elaborado pelos autores da pesquisa e respondido pelas mães após quatro meses de tratamento. Resultados: a média de idade das crianças que participaram do estudo foi 10 meses e o desvio-padrão de 4,9 meses. O resultado do questionário indicou associação entre idade e postura de lábios relatada pelos pais com o uso da placa palatina de memória, sendo que todas as crianças menores de 10 meses mantiveram o selamento labial, de acordo com os pais, durante o uso da placa; bem como entre idade e satisfação com o tratamento, sendo que as mães das crianças menores mostraram-se mais satisfeitas. Conclusão: os resultados do estudo indicam que houve associação entre idade e postura de lábios relatada pelos pais com o uso da placa, bem como entre idade e satisfação com o tratamento e sugerem que o tratamento precoce com a placa palatina de memória beneficia as crianças com Trissomia do 21. (AU)

Purpose: to verify if the age of children with Trisomy 21 and the time of use per day of the stimulating palatal plate influence the child's adaptation to the plate, the orofacial myofunctional changes perceived by the parents, and the family's satisfaction, after four months of treatment. Methods: 14 parents or legal guardians of children with Trisomy 21, aged between 3 and 20 months, participated in the study. Treatment with the stimulating palatal plate was carried out for four months. The child's adaptation to the plate, the orofacial myofunctional changes perceived by the parents, and the families' satisfaction with the treatment were investigated through a questionnaire prepared by the research authors and answered by the mothers after four months of treatment. Results: The mean age of the children who participated in the study was 10 months and the standard deviation was 4.9 months. The results of the questionnaire indicated an association between age and lip posture, reported by parents, during the use of the stimulating palatal plate, and all children under 10 months maintained lip closure, according to the parents, during the use of the plate. Age was also associated with satisfaction with the service, as the mothers of younger children were more satisfied. Conclusion: The study results indicate an association between age and lip posture, reported by the parents, during the use of the plate, and between age and satisfaction with the service. Thus, it suggests that early treatment with the stimulating palatal plate benefits children with Trisomy 21. (AU)

Objetivo: verificar si la edad de los niños con Trisomía 21 y el tiempo de uso por día de la placa palatina de memoria influyen en la adaptación del niño a la placa, los cambios miofuncionales orofaciales percibidos por los padres y la satisfacción de la familia, después de cuatro meses de tratamiento. Métodos: Participaron en el estudio 14 padres o tutores legales de niños con trisomía 21, con edades comprendidas entre los 3 y los 20 meses. El tratamiento con la placa de memoria palatina se llevó a cabo durante cuatro meses. La adaptación del niño al plato, los cambios miofuncionales orofaciales percibidos por los padres y la satisfacción de las familias con el tratamiento fueron investigados a través de un cuestionario elaborado por los autores y respondido por las madres, después de cuatro meses de tratamiento. Resultados: La edad media de los niños que participaron en el estudio fue de 10 meses y la desviación estándar fue de 4,9. El resultado del cuestionario indicó una asociación entre la edad y la postura de los labios, reportada por los padres, con el uso de la placa de memoria palatina, y todos los niños menores de 10 meses mantuvieron el sello de los labios, según los padres, durante el uso de la placa de memoria palatina, así como entre la edad y la satisfacción con el servicio. Las madres de niños más pequeños estaban más satisfechas. Conclusión: Los resultados del estudio indican que hubo asociación entre la edad y la postura de los labios, reportada por los padres, con el uso de la placa, así como entre la edad y la satisfacción con el servicio, y sugieren que el tratamiento temprano con la placa de memoria palatina beneficia a los niños con trisomía 21. (AU)

A review on the influence of rapid maxillary expansion and mandibular advancement for treating obstructive sleep apnea in children.

This article reviews the orthodontic alternatives for treating pediatric obstructive sleep apnea (OSA). OSA is a multifactorial disease that impairs craniofacial growth and the general health of a developing child and negatively worsens their quality of life. Therefore, it is important to timely diagnose and treat OSA to avoid the progress of the disease, which could otherwise lead to systemic, neurocognitive and social consequences in the patients. In the transverse direction, compression of the maxilla could decrease the diameter of the upper airways and reduce airflow. In the sagittal direction, a retrognathic mandible positioned more posteriorly to the tongue could reduce the available upper airway space and decrease airflow during sleep. Orthopedic treatments for mild to moderate OSA include maxillary expansion using rapid maxillary expansion devices and mandibular advancement using mandibular advancement appliances, which are treatment options only when skeletal discrepancies exist and should be applied after appropriate individual diagnosis for each orthodontic patient. Currently, limited evidence suggests that these therapies could reduce the signs and symptoms and the apnea-hypopnea index (AHI) of OSA.

Is photobiomodulation effective during maxillary expansion? A systematic review and meta-analysis.

We performed a systematic review on literature associated with meta-analyses to elucidate whether (I) low-level laser therapy (C) compared to placebo accelerates (O) bone neoformation in the region of the midpalatal suture in (P) patients undergoing transverse maxillary expansion. Two reviewers blindly performed targeted searches using the selection criteria (PICOS) in seven major databases and three grey literature databases, employing specific terms and their entrenchments. The RevMan® software (Review Manager, version 5.3, Cochrane Collaboration) was used to adapt the RoB summary illustration to the Cochrane 2.0 tool questions. Meta-analysis was performed using standardized mean difference (SMD) and Cohen's d calculation on random effects, tests for heterogeneity (I2 ) and publication bias (Egger and Begg), and one-of-out sensitivity analysis. GRADE (Grading of Recommendations Assessment, Development and Evaluation) was used for evidence quality analysis. Among the five studies included in the qualitative synthesis, three were included in the meta-analysis. All analysed studies were prospective randomized clinical trials. The risk of bias was such that the Egger (P = .1991) and Begg (P = .024) tests showed no significant risk of publication bias. The meta-analysis showed high heterogeneity (I2  = 81%, P < .00001), and 3 months after the operation, there was no significant difference between the photobiomodulation (PBMT) group and control group (P = .850) or between the subgroups of the periods evaluated after 3 months (P = 0.490). GRADE showed an SMD of 0.62. Photobiomodulation as an adjuvant therapy in patients undergoing transverse maxillary expansion has few benefits and is limited in shape, as it contributes to bone healing in the midpalatal suture region after a period of 3 months.

Rapid maxillary expansion supplementary methods: A scoping review of animal studies.

INTRODUCTION: Maxillary constriction is a relatively common condition. Various treatment modalities have been proposed for this condition such as rapid maxillary expansion (RME). Although RME can significantly expand the suture in a relatively short period of time, it has a number of drawbacks, mainly a lengthy retention period. The primary objective of this study was to assess the efficacy of the supplementary methods used in conjunction with RME for new bone formation (NBF) at the midpalatal suture (MPS). Relapse, bone healing, and root resorption were also studied as the secondary outcomes. MATERIALS AND METHODS: The PubMed, Embase, and Cochrane library online databases were searched according to the PRISMA-ScR guideline. Animal studies on the effects of non-surgical supplementary methods other than laser therapy on NBF in RME were included and reviewed. RESULT: Thirty-eight articles met the inclusion criteria. The supplementary methods were categorized into 6 groups: hormones, chemical agents, drugs, vitamins, proteins, and some other substances, which could not be assigned to any group. All the aforementioned substances enhanced NBF. Drugs such as bisphosphonates also increased bone resorption. The oestrogen hormone was shown to reduce treatment relapse. Lastly, stem cell application accelerated bone healing at the expanded MPS. CONCLUSION: Administration of hormones, chemical agents, drugs, vitamins, herbs, and proteins may improve the outcomes of RME, shorten the retention period and consequently, reduce relapse in animals. However, the generalizability of these findings is limited due to the insubstantial number of studies published on each substance.

New bone-generative effect of Salvia officinalis L. in the expanded midpalatal suture : An in vivo and in vitro study.

PURPOSE: The aims of this study were to evaluate the effects of systemic administration of Salvia officinalis Linnaeus (L.) leaf extract on new bone formation in the expanded premaxillary suture in rats in vivo and to examine the antioxidant effects and phenolic profile of Salvia officinalis (SO) leaf and root extracts in vitro. METHODS: Fourteen male Sprague Dawley rats were allocated to two groups: SO group (n = 7) and control group (n = 7). An open-loop spring was attached to the upper incisors of each rat to expand the premaxillae. A 5-day expansion period followed by a 12-day retention period was observed. The rats in the SO group received systemic administration of 20 mg SO/kg/day via the orogastric route for 17 days. Histomorphometric examinations were carried out to examine the amount of new bone formation, number of capillaries, and intensity of inflammatory cell response. Immunohistochemical analysis was conducted to examine the number of osteoblasts and osteoclasts. Leaf and root extracts of SO were also analyzed for antioxidant activity and phenolic compounds in vitro. RESULTS: Statistical analysis showed that the following were higher in the SO group than in the control group: new bone formation, number of osteoblasts and osteoclasts, intensity of inflammatory cell response (neutrophils, lymphocytes, and macrophages), and number of capillaries. The major compound identified in SO leaf extract was rosmarinic acid, while luteolin derivatives, salvianolic acid F, and medioresinol were also present. CONCLUSIONS: Salvia officinalis L. from leaf extract provided antioxidant effects and stimulated enhanced new bone formation in the expanded midpalatal suture after maxillary expansion in rats.

Effect of methylphenidate at different doses on new bone formation with rapid maxillary expansion: A micro-CT and histomorphometric study in rats.

OBJECTIVES: This study aimed to evaluate the effect of systemically administered methylphenidate hydrochloride (MPH) on new bone formation in premaxillary suture after rapid maxillary expansion (RME). SETTING AND SAMPLE POPULATION: Thirty-three Wistar rats were divided into four groups: Group 1 (high dose, 30/60 mg/kg MPH), Group 2 (low dose, 4/10 mg/kg MPH), Group 3 (positive control) and Group 4 (negative control). METHODS: RME was applied on the 70th day of the study. A 5-day RME period was followed by a 12-day retention period. The experiment was terminated on the 87th day. Micro-CT for radiological evaluation, haematoxylin-eosin and Masson's trichrome staining methods were used for histomorphometric evaluation. RESULTS: Among experimental groups with RME, the lowest number of osteoblasts and capillaries in Group 1 (P < .05). New bone formation, fibrous callus formation, distal osteotomy line, proximal osteotomy union and cortex remodelling were observed to be lower in Group 1 and Group 2 than Group 3 (P < .05). There was a statistically significant difference between Group 4 and each of the other groups (P = .000) in the evaluation of the results for bone mineral density, bone volume, bone volume percentage, trabecular thickness and trabecular number. CONCLUSIONS: MPH reduces cellular activity for new bone formation in suture in RME groups. Before performing rapid maxillary expansion in patients using MPH, the use of the drug should be postponed after a multidisciplinary decision process or clinical doses should be lowered.

Comparison of rapid maxillary expansion and pre-fabricated myofunctional appliance for the management of mouth breathers with Class II malocclusion.

OBJECTIVE: Pre-fabricated myofunctional appliances and rapid maxillary expansion (RME) has been used for the treatment of mouth-breathers with Class-II malocclusion. This study aimed to compare the treatment effects of hyrax and pre-fabricated myofunctional appliance (T4K) for the management of mouth breathers with Class II Malocclusion in mixed dentition stage. PATIENTS AND METHODS: Case records of mouth breathers with Class II Division 1 malocclusion patients treated at our institute with T4K or hyrax appliance between June 2015 to May 2019 were retrieved. The Pancherz analysis was used to compare the treatment effects. RESULTS: Data of 28 patients (14 in each group) were compared. Significant advancement of maxilla was seen in both groups while mandibular length improved only with the T4K appliance. SNA and SNB changes were significantly greater in the T4K group. Molar relationship improved in both groups. Molar correction was obtained by 55.6% skeletal change and 44.4% dental change with RME. In the T4K group the corresponding values were 48.1% and 51.9% respectively. CONCLUSIONS: Our results suggest that both pre-fabricated myofunctional appliance and RME are suitable for the treatment of mouth breathers with Class II malocclusion in the mixed dentition period. Sagittal correction of maxilla and mandible may be somewhat better with the T4K appliance. Although the dental compensation may be slightly more with the T4K appliance and it may inhibit the skeletal remodeling.

Evaluation of photobiomodulation therapy to accelerate bone formation in the mid palatal suture after rapid palatal expansion: a randomized clinical trial.

To evaluate the efficiency of photobiomodulation therapy (PBMT) in the midpalatal suture (MPS) and pain sensation in patients undergoing rapid palatal expansion (RPE). Thirty-four individuals with the diagnosis of skeletal maxillary hypoplasia were divided in two groups: laser (n = 18) and control (n = 16). Treatment plan consisted of the use of the Hyrax expander in all patients. Subjects in the laser group were irradiated with diode laser (980 nm, 0.3 W) in six spots bilaterally distributed along the MPS for 10 s during the active phase of treatment and after overcorrection (passive phase of RPE). Control group received sham irradiations with the laser in standby mode to characterize the placebo effect. Digital occlusal radiographs were performed at different time-points for bone formation evaluation in both groups. The effects of laser irradiation on pain were assessed by the visual analog scale (Wong-Baker Faces Pain Scale). Bone formation between groups was not significantly different (p = 0.2273). At 3 months, bone formation was not yet complete in both groups. Pain sensation was similar between groups (p = 0.3940). However, pain was significantly higher for the first 7 days of treatment compared with the 14th day. PBMT did not accelerate bone regeneration in the MPS and pain sensation was similar.

Surgically-assisted Rapid Maxillary Expansion under Local Anesthesia.

Developmental, traumatic and congenital factors, among many others, may lead to transverse maxillary deficiency (TMD). TMD can be corrected by orthodontic treatment, and may also require surgical intervention. The surgical technique is used in maxillary hypoplasia seen in cleft palate, crowding in maxillary teeth, which in cases where maxilla needs to be expanded more than 5 mm. Although it is a frequently used technique, there is no consensus on the operative technique and the apparatus used during the operation. Whether or not to separate, the pterygomaxillary junction is also one of the most common subjects of debate in this regard. In this case presentation, the transverse expansion of the maxilla was completed by means of surgically-assisted rapid maxillary expansion operation performed under local anesthesia without separating the pterygomaxillary junction and nasal septal osteotomy; and the patient, in whom orthodontic treatment had been completed, made a successful recovery without complications.

Evaluation of photobiomodulation effects on pain, edema, paresthesia, and bone regeneration after surgically assisted rapid maxillary expansion: Study protocol for a randomized, controlled, and double blind clinical trial.

BACKGROUND: Surgically assisted rapid maxillary expansion (SARME) generates an uncomfortable postoperative period accompanied by pain, edema, and paresthesia. There are few studies on the effect of photobiomodulation (PBM) after SARME and it was not possible to find studies on the efficacy of light emitted by diode (LED) after this type of intervention. The main objective of the study will be to evaluate the efficacy of PBM with LED in the control of pain, facial edema, paresthesia, and bone repair after SARME. METHODS: A randomized, double-blind, placebo-controlled clinical trial involving 72 participants aged from 18 to 45 years, who search the Department of Buccomaxillofacial Surgery and Traumatology of Mandaqui Hospital Complex, will be conducted. Immediately after surgeries, the participant will be inserted into the placebo or LED group. In the LED group, the participants will receive PBM with an extraoral device (660 and 850 nm with 6 J per point) and an intraoral device (660 nm with 2 J per point) and in the control group the person in charge of the application will simulate the irradiation with the devices kept off. The applications will be in the immediate postoperative period, 1, 2, 7, 14, 30, 60, 90, and 120 days after the end of the surgeries, when the evaluations will also be performed. Facial measurements, extra and intraoral sensitivity, pain and bone repair will be evaluated. Secondarily, data regarding the occurrence of headache; otalgia; nausea; bruising; nasolacrimation; epistaxis; dysphagia; systemic and superficial temperature in the operated region; use of analgesics and anti-inflammatories; anxiety and impact of oral health on the participants' quality of life will be computed. DISCUSSION: Since PBM has shown positive effects on postoperative complications of other types of oral surgery and also has a positive effect on bone repair after maxillary disjunction, surgically assisted or not, it seems clear the need to evaluate its performance regarding pain, edema, and paresthesia after these surgeries. TRIAL REGISTRATION: This protocol was registered in Clinical Trials platform (https://clinicaltrials.gov/) with the number NCT03814525, first published and last updated on January 24, 2019.

Técnica de disyunción horizontal del reborde alveolar con bisturí piezoeléctrico y colocación de implantes en el maxilar inferior: informe de casos clínicos / Horizontal split crest technique using a piezoelectric scalpel and immediate implant placement in the jaw: report of clinical cases

Objetivo: Presentar una técnica quirúrgica de disyunción con bisturí piezoeléctrico y expansión de rebordes delgados en maxilar inferior que permita la colocación de implantes en la posición tridimensional correcta en el mismo acto quirúrgico. Casos clínicos: Se presenta la resolución de dos casos clínicos de pacientes que acudieron a la Cátedra de Odontología Integral Adultos de la Facultad de Odontología de la Universidad de Buenos Aires. Ambos requerían la colocación de implantes en sectores posteroinferiores. Las imágenes tomográficas mostraban adecuada altura del reborde alveolar pero deficiente espesor para la colocación de implantes en la posición tridimensional correcta. Se decidió realizar una técnica de disyunción horizontal del reborde alveolar con bisturí piezoeléctrico, expansión del reborde y colocación de implantes e injerto óseo particulado de forma simultánea. Luego de 3 meses, se efectuó la segunda cirugía para iniciar la rehabilitación protésica. Conclusión: La técnica de disyunción horizontal del reborde alveolar mediante el uso del bisturí piezoeléctrico permitió ubicar al implante en la posición tridimensional correcta dentro del tejido óseo nativo sin la necesidad de realizar regeneraciones complejas en rebordes alveolares delgados (AU)

Aim: Present the horizontal split crest technique with a piezoelectric scalpel and the immediate implant placement in the correct tridimensional position, in thin mandibular alveolar ridges. Cases report: The surgical resolutions of 2 clinical cases of patients who attended the Adult Integral Dentistry Chair of the Faculty of Dentistry of the UBA, are presented. Both patients required implant placement in posterior madibular residual ridge. The tomographic images showed adequate height of the alveolar ridge but poor thickness for implants placement in a correct three-dimensional position. It was decided to perform a horizontal split crest technique of the alveolar ridge with piezoelectric scalpel, ridge expansion, and immediate implant placement with xenograft. After 3 months, the second surgery was performed to start with the prosthetic rehabilitation. Conclusion: The horizontal split crest technique using a piezoelectric scalpel, allowed immediate implant placement in the correct tridimensional position within native bone tissue, avoiding a guided bone regeneration technique, in these cases with thin alveolar ridges (AU)

Effects of different settings for 940 nm diode laser on expanded suture in rats.

OBJECTIVES: To evaluate the effects of the Indium Gallium Arsenide Phosphoride (InGaAsP) diode laser at different energy levels on orthopedically expanded midpalatal sutures of rats. MATERIALS AND METHODS: Eighty Wistar rats were randomly divided into four groups: a control group and low-, moderate-, and high-level laser groups with amounts of energy irradiated at 0 J, 18 J, 42 J, and 60 J, respectively. Each group was divided into two subgroups (n = 10) according to the schedule of sacrifice (7 and 21 days). Laser application (940 ± 10 nm, 0.1 W) was completed twice weekly until sacrifice. The number of osteoblasts (OB), osteocytes (OC), and vessels (V); area of connective tissue (CT); inflammation (IN); and newly formed bone (NB); as well as the ratio of newly formed bone to the total bone area (N/T) were evaluated statistically at a significance level of P < .05. RESULTS: For the low-level laser group, OB, NB, and N/T were significantly higher, and CT was lower, on both the 7th and 21st days. The amount of OC was significantly higher in the low-level laser group compared with the control group on the 7th day and the control and high-level laser groups on the 21st day. The IN was significantly higher for the high-level group on the 21st day compared with other groups. Both the moderate-level and high-level laser groups possessed fewer vessels than the low-level laser group on the 21st day. CONCLUSIONS: The InGaAsP laser at the low dosage induced a favorable effect on bone formation in the orthopedically expanded midpalatal suture of rats.

Osteo-regeneration personalized for children by rapid maxillary expansion: an imaging study based on synchrotron radiation microtomography.

BACKGROUND: Personalized maxillary expansion procedure has been proposed to correct maxillary transversal deficiency; different protocols of stem cell activation have been suggested and rapid maxillary expansion (RME) is the most commonly used among clinicians. The present study aimed to quantify in three-dimensions (3D) the osteo-regeneration of the midpalatal suture in children submitted to RME. METHODS: Three patients (mean age 8.3 ± 0.9 years) were enrolled in the study to preform biopsy of midpalatal suture. Two patients (subjects 1 and 2) were subjected to RME before biopsy. The third patient did not need maxillary expansion treatment and was enrolled as control (subject 3). Midpalatal suture samples were harvested 7 days after RME in subject 1, and 30 days after RME in subject 2. The samples were harvested with the clinical aim to remove bone for the supernumerary tooth extraction. When possible, maxillary suture and bone margins were both included in the sample. All the biopsies were evaluated by complementary imaging techniques, namely Synchrotron Radiation-based X-ray microtomography (microCT) and comparative light and electron microscopy. RESULTS: In agreement with microscopy, it was detected by microCT a relevant amount of newly formed bone both 7 days and 30 days after RME, with bone growth and a progressive mineralization, even if still immature respect to the control, also 30 days after RME. Interestingly, the microCT showed that the new bone was strongly connected and cross-linked, without a preferential orientation perpendicular to the suture's long axis (previously hypothesized by histology), but with well-organized and rather isotropic 3D trabeculae. CONCLUSIONS: The microCT imaging revealed, for the first time to the authors' knowledge, the 3D bone regeneration in children submitted to RME.

Effects of laser therapy on patients who underwent rapid maxillary expansion; a systematic review.

Rapid maxillary expansion (RME) is one of the common treatments of transverse maxillary deficiency, and low-level laser therapy (LLLT) is one of the recommended solutions to enhance biological wound or bone healing. This review article aims to answer the following question: "What are the effects of LLLT, on patients who underwent surgical or non-surgical RME, in improving clinical success, wound healing, and bone regeneration?" A search in PubMed, Scopus, Web of Science, and ProQuest databases was performed, with a focus on the appropriate key words. Related articles, up to May 2017, were screened, and the full text of the randomized controlled trials (RCT) were comprehensively read and subjected to quality assessments. A total of 1804 articles were included after the initial search. Four RCTs were eligible in randomization and methodology. The applied wavelength varied from 660 to 830 nm with an output range of 40-100 mW. Also, the highest exposed energy was 420 J/cm2 and the lowest was 100 J/cm2. The exposure time differed from 20 to 84 s in each defined point in the palate. Based on the RCTs available, LLLT is better to be used at initial phase of RME, because it has some benefits in increasing the rate of bone remodeling.

Evaluation of bacterial flora composition on teeth and periodontal tissues in patients in treatment with rapid palatal expander.

Patients in treatment with rapid palatal expander (RPE) require professional assistance and more meticulous instructions on oral hygiene, since this appliance predisposes to gingivitis and caries. The aim of this work is to analyse the variability of the oral microbial flora found in patients in treatment with RPE with occlusal acrylic splint. It was also investigated whether the association of an antimicrobial mouthwash was useful during orthodontic treatment or whether regular and specific home oral hygiene manoeuvres were sufficient to maintain a good plaque control. The last goal was to highlight which of the different mouthwashes was the most effective in reducing the bacterial load. The patients were divided into 3 test groups and each one of them had a different mouthwash (chlorhexidine and sodium fluoride, fluorine, essential oils) randomly assigned. There was also a control group. Plaque samples were analysed through cultural analysis and PCR from T0 to T4 (8 months). Chlorhexidine mouthwash reduces the bacterial count by 96.08%, the fluorine by 94.50% and the essential oils by 95.74%. The results of the three mouthwashes are superimposable and although chlorhexidine gives the highest rate of bacteria reduction, its side effects lead the authors to prefer the essential oils.

The Effect of Low-Level Laser Therapy on Bone Healing After Rapid Maxillary Expansion: A Systematic Review.

OBJECTIVE: The study aimed to systematically appraise the evidence on the effects of low level laser therapy (LLLT) on bone healing following rapid maxillary expansion (RME). METHODS: Electronic search was performed in MEDLINE, Scopus, and Embase databases using appropriate Medical Subject Heading terms, with no time restriction. ClinicalTrials.gov ( www.clinicaltrials.gov ) was also searched using the terms "low level laser therapy" and "maxillary expansion." SELECTION CRITERIA: Original research articles on human clinical trials that involved both RME and LLLT were included. Animal studies were also assessed on an exploratory basis. RESULTS: The search strategy resulted in 12 publications (4 randomized controlled trials, 8 animal studies). In human studies, bone density was assessed radiographically (either two-dimensional or three-dimensional imaging). Regardless of the discrepancies in the intervention protocols, the total of the trials revealed that LLLT had stimulatory effects on bone regeneration after RME. The studies in animal models measured the formation and maturation of new bone qualitatively or quantitatively. CONCLUSIONS: Despite the limited evidence, LLLT seems to be a promising intervention for stimulating immediate bone regeneration and healing after midpalatal suture expansion. Long-term, randomized clinical trials are needed to formulate safe results and establish a reliable clinical protocol, rendering the method clinically applicable.

A preliminary investigation of the effect of relaxin on bone remodelling in suture expansion.

Background and objectives: Relaxin (RLN) is an insulin-like hormone associated with extracellular matrix degradation, osteoclastogenesis, and osteoblast differentiation. This study aimed to assess the effect of RLN during and after lateral expansion of murine calvarial sagittal sutures. Materials and methods: RLN was injected topically using a nano-sized liposome carrier into the sagittal sutures of 8- to 10-week-old wild type mice just before lateral expansion. Suture morphology, bone mineral density (BMD), and bone volume were analysed by micro-computed tomography. Collagen deposition and osteoclast differentiation were observed by Verhoeff-Van Gieson (VVG) and tartrate-resistant acid phosphatase (TRAP) staining, respectively. Results: Less collagen staining and higher tissue-specific relaxin/insulin-like family peptide receptor (Rxfp)-1 and -2 expression were observed in the RLN-treated samples after 48 hours. Increased BMD and volume, and thick well-organised osteoid tissue, with multinucleated TRAP-positive cells, were observed in RLN-treated samples after 1 week. Increased Rxfp-1 expression was observed in the sagittal sutures in the mid-suture fibrous tissue following RLN treatment. Rxfp-2 was only expressed in the calvarial bone under tensile stimulation and RLN treatment further increased its expression. Limitations: RLN-liposomes were not detected at any instance under the current experimental conditions. This is a preliminary study and the sample number limits the power of its results. VVG staining cannot quantify collagen contents but can provide preliminary information on the presence of collagen fibres. Conclusions: RLN treatment may modify bone remodelling and collagen metabolism during and after suture expansion.

Laser and LED phototherapy on midpalatal suture after rapid maxilla expansion: Raman and histological analysis.

The aim of this study was to analyze the effect of laser or LED phototherapy on the acceleration of bone formation at the midpalatal suture after rapid maxilla expansion. Forty-five rats were divided into groups at 7 days (control, expansion, expansion and laser irradiation, and expansion and LED irradiation) and into 14 days (expansion, expansion and laser in the 1st week, expansion and LED in the 1st week, expansion and laser in the 1st and 2nd weeks, expansion and LED in the 1st and 2nd weeks). Laser/LED irradiation occurred every 48 h. Expansion was accomplished with a spatula and maintained with a triple helicoid of 0.020-in stainless steel orthodontic wire. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm2, t = 257 s, SAEF of 18 J/cm2) or a LED (λ850 ± 10 nm, 150 ± 10 mW, spot of 0.5 cm2, t = 120 s, SAEF of 18 J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Raman spectroscopy and histological analyses of the suture region were carried and data was submitted to statistical analyses (p ≤ 0.05). Raman spectrum analysis demonstrated that irradiation increases hydroxyapatite in the midpalatal suture after expansion. In the histological analysis of various inflammation, there was a higher production of collagen and osteoblastic activity and less osteoclastic activity. The results showed that LED irradiation associated to rapid maxillary expansion improves bone repair and could be an alternative to the use of laser in accelerating bone formation in the midpalatal suture.