Transverse Deficiency Research Articles

Tridimensional Changes in Mandibular Arch after Rapid Maxillary Expansion Therapy: A Clinical Study.

Aim: The upper jaw transverse deficit is certainly one of the most common clinical issues in the orthodontic field. It can be due to skeletal or dental factors, and its etiology may be both genetic and environmental. Rapid maxillary expanders (RMEs) are certainly the most effective appliance for upper transverse deficiency correction. The aim of this study was to evaluate the changes that occurred in the mandibular arch during treatment with RMEs in growing subjects by analyzing tridimensional lower digital casts. Materials and Methods: The study group (SG) consisted of 20 subjects (10 M, 10 F; mean age 9.4 ± 2.8 years old) randomly selected at the Department of Orthodontics at the University of Rome, "Tor Vergata". The inclusion criteria were negative posterior transverse interarch discrepancy ≥ 4 mm, mixed dentition phase with first permanent molars erupted, and prepubertal skeletal maturation stage (CS1-2), evaluated on a lateral radiograph through the Cervical Vertebral Maturation method. The SG was compared to an untreated control group (CG) of 20 subjects (10 M, 10 F, mean age 8.7 ± 2.3 years old) enrolled with the same inclusion criteria. The SG was treated by using RMEs. Dental casts of the lower arch were taken at two different times (T0-T1 = 6 months). All the dental casts were scanned with an OrthoXscan (Dentaurum 6mmbh E Co., Ispringen, Germany) and twenty points on the mandibular arch were digitized using Viewbox software. A Student t-test was used to compare the means of the quantitative variables associated with the effect of the device over time T0 and T1. Results: The results show a statistically significant increase (p < 0.05) in the intercanine and the intermolar diameters between the times T0 and T1 when compared to the CG. Conclusions: Rapid maxillary orthopedic expansion may achieve an increase in mandibular intercanine and intermolar diameter.

Effects of rapid maxillary expansion on anchorage alveolar bone meta-analysis

Purpose Rapid maxillary expansion (RME) is a routine method for correcting transverse maxillary deficiency. This paper investigated the effect of RME on anchorage alveolar bone and examined the differences between micro-implant-assisted RME and conventional RME. Methods Relevant articles were selected from the PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases. Review Manager software (v.5.3) was used for the pooled analysis and Cochran Q and I 2 statistic tests were used to assess the heterogeneity. Results Following conventional RME, the distal buccal alveolar bone thickness and the mesiobuccal alveolar thickness of the maxillary first molars were significantly reduced. Hyrax (standard mean difference [SMD]: −0.93, 95% confidence interval [CI]: −1.20–0.66) and Haas procedures (SMD: −0.88, 95% CI: −1.40–0.36) significantly reduced the buccal vertical alveolar height of the maxillary first molars. Similar results were obtained for the maxillary first premolars following RME. The thickness of the buccal alveolar bone decreased with conventional RME compared to when using the method assisted by micro-implants. Conclusions Conventional RME can reduce the thickness and vertical height of maxillary alveolar bone, and there is less loss of alveolar bone when using micro-implant-assisted RME. Further research is needed to validate the findings.

Prenatal radiographic evaluation of congenital transverse limb deficiencies: A scoping review.

Congenital transverse deficiencies are horizontal deficiencies of the long bones that occur with a reported incidence as high 0.38%. They can occur alone or represent a manifestation of a various clinical syndromes. Diagnosis has traditionally comprised of conventional radiography and prenatal imaging studies. There has been much advancement regarding prenatal imaging modalities to allow for early diagnosis and appropriate treatment. To summarize the current state of knowledge on congenital transverse limb deficiencies and to provide an update regarding the radiographic evaluation of congenital transverse limb deficiencies. This IRB-exempt scoping review followed the PRISMA-ScR checklist for scoping reviews strictly. Five search engines were searched for a total of 265 publications. Four authors reviewed these during the screening process. Of these, 51 studies were included in our article. Prenatal magnetic resonance imaging (MRI), 3D Ultrasound, and multidetector Computed tomography (CT) exist are emerging modalities that have the potential to improve diagnosis. Use of the appropriate classification system, three-dimensional ultrasonography with a maximum intensity projection, and appropriate use of prenatal MRI and prenatal CT can improve diagnosis and inter-provider communication. Further scholarly efforts are required to develop improve standardized guidelines regarding the pre-natal radiographic evaluation of congenital limb deficiencies.

Rehabilitation of severe dentofacial deformity after early radiotherapy of retinoblastoma: a case report

BackgroundRetinoblastoma is an intraocular cancer of infancy and childhood, which has been treated with radiation therapy and chemotherapy. Radiation on growing patients can cause deterioration in maxillofacial growth and development that leads to severe skeletal discrepancies between the maxilla and mandible, and dental problems such as crossbite, openbite, and hypodontia.Case presentationWe present the case of a 19-year-old Korean man with chewing disability and dentofacial deformities. He had undergone enucleation of the right eye and radiation therapy of the left eye due to retinoblastoma 100 days after birth. Subsequently, he received cancer therapy for the secondary nasopharyngeal cancer at the age of 11 years. He was diagnosed with severe skeletal deformity including sagittal, transverse, and vertical growth deficiency of the maxilla and midface, and with class III malocclusion, severe anterior and posterior crossbite, posterior openbite, multiple missing upper incisors, right premolars, and second molars, and impaction of the lower right second molars. To restore impaired functions and esthetics of the jaw and dentition, the orthodontic treatment combined with two jaw surgery was performed. At the end of surgical orthodontics, dental implants were placed for prosthetic treatment of missing teeth. Additional plastic surgery for zygoma elevation was done with calvarial bone graft followed by fat graft. Facial esthetics and occlusal functions of patient were favorably enhanced with the improvement of skeletal discrepancy and the rehabilitation of maxillary dentition by prosthetic work. At the 2-year follow-up, the skeletal and dental relationships and implant prosthetics were well maintained.ConclusionIn an adult patient with dentofacial deformities caused by early cancer therapy in the head and neck area, interdisciplinary interventions including additional plastic surgery of zygoma depression and prosthetic work of missing teeth as well as surgical–orthodontic treatment could establish favorable facial esthetics and oral rehabilitation.

Comparison of the effects of different rapid maxillary expansion techniques on craniofacial structures: a finite element analysis study

AimTo compare the effects of three different maxillary expansion appliances with five different types of expansion modalities on stress distribution and displacement on the maxilla and its adjacent craniofacial structures using the finite element method (FEM).Materials and methodsCone-beam computed tomography data of a patient with maxillary transverse deficiency were rendered into a three-dimensional model of craniomaxillary structures. The expansion appliances included tooth-borne, hybrid, and bone-borne expanders. Five different expansion modalities were applied to each expander [conventional Rapid Maxillary Expansion (RME) (type 1), midpalatal suture cortico-puncture-assisted RME (type 2), LeFort l cortico-puncture-assisted RME (type 3), surgically assisted RME (SARME) without pterygomaxillary junction (PMJ) separation (type 4), and SARME with bilateral PMJ separation (type 5)]. The numerical and visual data were analyzed.ResultsThe highest amount of stress accumulation on teeth was found in the tooth-borne and hybrid groups. On the other hand, more stress concentration on the maxilla was observed in the bone-borne group. SARME cuts with PMJ separation increased total movement by reducing the stress on the midpalatal suture in all groups. While types 1, 2, and 3 were similar in terms of the amounts of displacement, types 4 and 5 increased the total amount of displacement in all groups. The total amounts of displacements from the highest value to the lowest value for the anterior and posterior maxilla were in the bone-borne, tooth-borne, and hybrid groups.ConclusionsSARME cuts were effective in reducing stress on the teeth, but the cortico-puncture application affected neither the stress values on the teeth nor the transverse displacement in the tooth-borne expanders. Surgical procedures such as SARME and corticotomy should be used with bone-borne devices to improve the outcomes of maxillary expansion procedures.

Do Nails and Nubbins Matter? A Comparison of Symbrachydactyly and Transverse Deficiency Phenotypes

Transverse deficiency (TD) and symbrachydactyly may be difficult to distinguish due to shared phenotypes and a lack of pathognomonic features. The 2020 Oberg-Manske-Tonkin classification update modified these anomalies to include "with ectodermal elements" for symbrachydactyly and "without ectodermal elements" for TD as a defining differentiating characteristic. The purpose of this investigation was to characterize ectodermal elements and the level of deficiency and to examine whether ectodermal elements versus the level of deficiency was a greater determining factor for Congenital Upper Limb Differences (CoULD) surgeons making the diagnosis. This was a retrospective review of 254 extremities from the CoULD registry with a diagnosis of symbrachydactyly or TD by pediatric hand surgeons. Ectodermal elements and the level of deficiency were characterized. A review of the registry radiographs and photographs was used to classify the diagnosis and compare it with the diagnosis given by the pediatric hand surgeons. The presence/absence of nubbins versus the level of deficiency as the determining factor to differentiate the pediatric hand surgeons' diagnosis of symbrachydactyly (with nubbins) versus TD (without nubbins) was analyzed. Based on radiographs and photographs of the 254 extremities, 66% had nubbins on the distal end of the limb; of the limbs with nubbins, nails were present on 51%. The level of deficiency was amelia/humeral (n= 9), <1/3 transverse forearm (n= 23), 1/3 to 2/3 transverse forearm (n= 27), 2/3 to full forearm TD (n= 38), and metacarpal/phalangeal (n= 103). The presence of nubbins was associated with a four times higher likelihood of a pediatric hand surgeon's diagnosis of symbrachydactyly. However, a distal deficiency is associated with a 20-times higher likelihood of a diagnosis of symbrachydactyly than a proximal deficiency. Although both the level of deficiency and ectodermal elements are important, the level of deficiency was a greater determining factor for a diagnosis of symbrachydactyly versus TD. Our results suggest that the level of deficiency and nubbins should both be described to help provide greater clarity in the diagnosis of symbrachydactyly versus TD. Diagnostic IV.

The influence of obstructive sleep apnea syndrome on the orthodontic treatment decision in children and adolescents. Part 2: Which orthodontic treatments for children with apnea?

Sleep-disordered breathing could affect 10% of an orthodontic population. The integration of obstructive sleep apnea syndrome (OSAS) diagnosis could influence the choice of orthodontic techniques or their implementation, with the aim of improving ventilatory function. The author summarizes the clinical studies using dentofacial orthopedics, alone or in combination with other interventions, in pediatric OSAS or the repercussions of orthodontic interventions on upper airways. For the same orthodontic anomaly, in particular, transverse maxillary deficiency, the temporality and the modality of treatment could be modified by a diagnosis of OSAS. It could be recommended to propose early orthopedic maxillary expansion, seeking to potentiate its skeletal effect, to reduce the severity of OSAS. Class II orthopedic devices have shown interesting results but the evidence value of the studies is not yet sufficient to recommend them widely and as an early treatment. Extractions of permanent teeth do not significantly reduce the upper airway. OSAS in children and adolescents includes several endotypes and phenotypes for which orthodontics may or may not be indicated. It is not recommended to orthodontically treat an apneic patient with no significant malocclusion, for the sole purpose of having an effect on the respiratory tract. The orthodontic therapeutic decision is likely to be modified by a diagnosis of sleep-disordered breathing underlining the interest in systematic screening.

Routine Screening for Fetal Limb Abnormalities in the First Trimester

Objective: To evaluate the routine screening for fetal limb abnormalities in the first trimester. Study Design: Prospective study Place and Duration of Study: Department of Radiology and Department of Obstetrics &amp; Gynaecology, Khirpur Medical College, Khairpur Mir’s from 1st October 2020 to 30th September 2022. Methodology: The study enrolled all pregnant women in visiting the Gynaecology OPD for routine check-up. All the cases were referred to ultrasound diagnostic for screening of fetal limb abnormalities. The total sample size of the study was assigned as 1000 fetuses from 980 women as 10 women had twin pregnancies. Limb reduction shortcomings included transverse-limb reduction deficit as well as longitudinal-limb reduction deficit as seen through absent radius and also club hand, absent fibula phocomelia. The diagnosis of the limb shortening was based on the length of long bone if &lt;5th percentile. Lethal skeletal dysplasia suspicion was based on narrow thorax and long bone abnormalities. Results: The mean age of the pregnant women was 27.6±5.3 year. Around 26% of the women were nulliparous. The fetal limb anomaly was presented in 0.9% of the total cases. Within these, 0.7% was those women with single fetus while 0.2% had twin pregnancy. There were 60% of the women who were identified with fetal anomaly on their first screening visit within 1st trimester transverse limb anomaly was observed in 2 case within first trimester whereas 2 cases of club foot were identified in first trimester and one in third trimester. Conclusion: The fetal limb anomaly can be feasibly screened within first trimester. It has a prevalence of 0.9% with transverse limb deficiencies and club foot to be presented in highest frequency. Keywords: Fetal limb abnormalities, First trimester, Prevalence

Three-Dimensional Evaluation Effects of Microimplant-Assisted Rapid Palatal Expansion on the Upper Airway Volume: A Systematic Review and Meta-Analysis

Microimplant-assisted rapid palatal expansion is increasingly used clinically; however, the effect on the upper airway volume in patients with maxillary transverse deficiency has not been thoroughly evaluated yet. The following electronic databases were searched up to August 2022: Medline via Ovid, Scopus, Embase, Web of Science, Cochrane Library, Google Scholar, and ProQuest. The reference lists of related articles were also reviewed by manual search. The Revised Cochrane Risk of Bias Tool for randomized trials (ROB2) and the Risk of Bias in non-randomized Studies of Interventions (ROBINS-I) tool were used to evaluate the risks of bias of the included studies. The mean differences (MD) and 95% confidence intervals (CI) of changes in nasal cavity and upper airway volume were analyzed using a random-effects model, and subgroup and sensitivity analyses were also performed. Two reviewers independently completed the process of screening studies, extracting data, and assessing the quality of studies. In total, twenty-one studies met the inclusion criteria. After assessing the full texts, only thirteen studies were included, with nine studies selected for quantitative synthesis. Oropharynx volume increased significantly after immediate expansion (WMD: 3156.84; 95% CI: 83.63, 6230.06); however, there was no significant change in nasal volume (WMD: 2527.23; 95% CI: -92.53, 5147.00) and nasopharynx volume (WMD: 1138.29; 95% CI: -52.04, 2328.61). After retention a period, significant increases were found in nasal volume (WMD: 3646.27; 95% CI: 1082.77, 6209.77) and nasopharynx volume (WMD: 1021.10; 95% CI: 597.11, 1445.08). However, there was no significant change after retention in oropharynx volume (WMD: 789.26; 95% CI: -171.25, 1749.76), palatopharynx volume (WMD: 795.13; 95% CI: -583.97, 2174.22), glossopharynx volume (WMD: 184.50; 95% CI: -1745.97, 2114.96), and hypopharynx volume (WMD: 39.85; 95% CI: -809.77, 889.46). MARPE appears to be linked with long-term increases in nasal and nasopharyngeal volume. However, high-quality clinical trials are required to further verify the effects of MARPE treatment on the upper airway.

Maxillary transverse deficiency diagnosed by 3 methods and its relationship with molar angulation in patients with skeletal Class III malocclusion

The objective of this study was to evaluate the relationship between maxillary transverse deficiency (MTD) diagnosed by 3 methods and molar angulation measured in 3-dimensions in patients with skeletal Class III malocclusion, which could give reference to the selection of diagnostic methods in MTD patients. Cone-beam computed tomography data of 65 patients with skeletal Class III malocclusion (mean age 17.35 ± 4.45 years) were selected and imported into MIMICS software. Transverse deficiencies were evaluated by 3 methods, and molar angulations were measured after reconstructing 3-dimensional planes. Two examiners performed repeated measurements to assess the intraexaminer and interexaminer reliability. Pearson correlation coefficient analyses and linear regressions were performed to determine the relationship between a transverse deficiency and molar angulations. One-way analysis of variance was used to compare the diagnostic results of 3 methods. The novel molar angulation measurement method and 3 MTD diagnostic methods have the interexaminer and intraexaminer intraclass correlation coefficient values>0.6. The transverse deficiency diagnosed by 3 methods was significantly and positively correlated with the sum of molar angulation. There was a statistically significant difference for the transverse deficiencies diagnosed by the 3 methods. The transverse deficiency was significantly higher in Boston University's analysis than in Yonsei's analysis. Clinicians ought to choose the diagnostic methods properly, considering the feature of the 3 methods and the individual difference of each patient.

Soft- and Hard-Tissue Thicknesses in Patients with Different Vertical Facial Patterns and the Transverse Deficiencies, An Integrated CBCT-3D Digital Model Analysis

Different vertical facial patterns may present different bone and gingival thicknesses at the molar level and can be influenced by the dental compensations that manifest in the presence of transverse bone discrepancies. A retrospective analysis was made of 120 patients divided into three groups according to their vertical facial patterns (mesofacial, dolichofacial or brachyfacial). Each group in turn was divided into two subgroups according to the presence or absence of transverse discrepancies assessed by cone-beam computed tomography (CBCT). The bone and gingival measurements were made integrating a CBCT-3D digital model of the patient dentition. In the brachyfacial patients, the distance from the palatine root to the cortical bone corresponding to the right upper first molar was significantly greater (1.27 mm) than in the dolichofacial (1.06 mm) and mesofacial (1.03 mm) (p < 0.05) patients. The brachyfacial and mesofacial patients with transverse discrepancies presented a greater distance from the mesiobuccal root of the left upper first molar and from the palatine root to the cortical bone, while in the dolichofacial individuals the distances were shorter (p < 0.05); The presence of transverse bone discrepancies in brachyfacial and mesofacial patients without posterior cross-bite implies a better dentoalveolar expansion prognosis than in dolichofacial individuals.

Transverse Maxillary Deficiency Predicts Increased Upper Airway Collapsibility during Drug-Induced Sleep Endoscopy.

To examine the relationship between craniofacial skeletal anatomy and objective measures of pharyngeal collapse obtained during drug-induced sleep endoscopy. We hypothesized that transverse maxillary deficiency and an increased pharyngeal length will be associated with higher levels of pharyngeal collapsibility. Cross-sectional analysis in a prospective cohort. University Hospital. A cross-sectional analysis was conducted in a cohort of consecutive patients from the positive airway pressure(PAP) alternatives clinic who underwent computed tomography (CT) analysis and drug-induced sleep endoscopy for characterization of upper airway collapsibility. PAP titration was used to determine pharyngeal critical pressure (PCRIT ) and pharyngeal opening pressure (PhOP). CT metrics included: Transverse maxillary dimensions (interpremolar and intermolar distances) and pharyngeal length (posterior nasal spine to hyoid distance). The cohort (n = 103) of severe obstructive sleep apnea (Apnea and Hipopnea Index 32.1 ± 21.3 events/h) was predominantly male (71.8%), Caucasian (81.6%), middle-aged (54.4 ± 14.3 years), and obese (body mass index[BMI] = 30.0 ± 4.9 kg/m2 ). Reduced transverse maxillary dimensions were associated with higher PCRIT (intermolar distance: β [95% confidence interval, CI] = -.25 [-0.14, -0.36] cmH2 O/mm; p = .03) and PhOP (Interpremolar distance: β = -.25 [-0.14, -0.36] cmH2 O/mm; p = .02). Longer pharyngeal length was also associated with higher PCRIT (β = .11 [0.08, 0.14] cmH2 O/mm, p = .04) and PhOP (β [95% CI] = .06 [0.03, 0.09] cmH2 O/mm, p = .04). These associations persisted after adjustments for sex, age, height, and BMI. Our results further the concept that skeletal restriction in the transverse dimension and hyoid descent areassociated with elevations in pharyngeal collapsibility during sleep, suggesting a role of transverse deficiency in the pathogenesis of airway obstruction.

A novel maxillary transverse deficiency diagnostic method based on ideal teeth position

BackgroundThis study proposed a novel maxillary transverse deficiency diagnostic method and evaluated the skeletal Class I and the mild skeletal Class III groups.MethodsPre-treatment data from 30 mild skeletal Class III and 30 skeletal Class I patients were collected and uploaded to the Emeiqi Case Management System to design the ideal teeth positions. On these positions, the first bi-molars width was measured at the central fossa and center resistance, the maxillary first bi-premolars width was measured at the central fossa, and the mandibular first bi-premolars width was measured at the distal contact point by Mimics, then width differences of two groups were calculated respectively.ResultsAt ideal teeth positions, there was no statistically significant difference in the maxillomandibular width in the premolar area between the two groups, but there was in the molar area, and this difference was caused by the difference in mandible width between the two groups.ConclusionsWe proposed a new transverse diagnostic method and found that even the Class I group was not quite up to standard in the molar area on ideal teeth positions, and the Class III group had more severe maxillary transverse deficiency than the Class I group. Meanwhile, the maxillary transverse deficiency in the Class III group was mainly caused by the larger width of the mandible.

Different rapid maxillary expansion methods in the treatment of adult patients with obstructive sleep apnea hypopnea syndrome

Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common sleep respiratory disorder characterized by upper respiratory collapse during sleep, with a high prevalence and potentially fatal complications. Currently, maxillary transverse deficiency are considered to be an important pathogenic factor of OSAHS. For patients with poor compliance with positive airway pressure therapy, rapid maxillary expansion can increase the volume and ventilation of the upper respiratory tract, which is an alternative treatment. This paper reviewed the current research on surgically assisted rapid palatal expansion, miniscrew assisted rapid palatal expansion, and distraction osteogenesis maxillary expansion in the treatment of adult OSAHS. By comparing the indications, contraindications, complications, efficacy and long-term stability of the three treatment methods, it provided reference for treatment of patients with OSAHS.

Republication de : Pediatric maxillary expansion has a positive impact on hearing? A systematic review and meta-analysis

Hearing loss is a highly prevalent condition in the pediatric population. Pediatric maxillary expansion is a widespread treatment to address transverse maxillary deficiency. First reports describing an association between improvements for patients with HL and PME initiated in the 1960s. In this systematic review and meta-analysis we aim to review the role of maxillary expansion in reducing conductive hearing loss in pediatric population. Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked. Main outcome was expressed as the difference between air-bone gap, compliance, ear volume and conductive hearing thresholds before and after treatment and the 95% confidence interval. A total of 10 studies (218 patients) met inclusion criteria. The pooled data in the meta-analysis under a random effects model shows a statistically significant difference of 10.57 dB mean reduction after palatal expansion. The air-bone gap was significantly reduced by 5.39 dB (CI 95% 3.68, 7.10). Compliance and volume were assessed in three studies, with a non-significant positive difference in the compliance (0.14) and a statistically significant difference for volume (0.80) after palatal expansion. This systematic review and meta-analysis found a positive effect of pediatric maxillary expansion in conductive hearing loss in well-select children. However, results cannot be extrapolated for children with conductive hearing loss without an accompanying orthodontic indication (maxillary constriction). It showed that the existing prospective studies exhibited qualitative pitfalls, limiting the ability to obtain conclusive evidence about the role of pediatric maxillary expansion on conductive hearing loss in children.

Effects of different distractor positions on the formation of expansion, stress and displacement patterns in surgically assisted rapid maxillary expansion without pterygomaxillary disjunction: a finite element analysis study

Skeletal orthopedic expansion of maxilla is accepted as a reliable method for the treatment of transverse maxillar deficiency in growing patients. The aim of the study was to evaluate the effects of different palatal distractor positions on the expansion, stress and displacement patterns of the structures of craniofacial complex in surgical assisted rapid maxillary expansion without pterygomaxillary disjunction (PTMD) with the help of finite element analysis(FEA). Four facial skeleton models with different distractor positions (first premolar, second premolar, first molar, second molar regions) were created. In all finite element models median and lateral osteotomies were performed, without PTMD. Stress distribution was evaluated after 5 mm activation of the transpalatal distraction in all models using the nonlinear solution method in FEA. Unilateral displacement(mm) and stress distribution(MPa) were measured in three directions (x, y, and z axes) of craniofacial and maxillofacial structures in the symmetrical finite element models. In all models, the unilateral transverse displacements of the anterior teeth were greater than those of the posterior teeth, and the greatest displacement was at the central incisor level. The greatest displacement values at the central incisor level, at the anterior nasal spine(ANS) and at the posterior nasal spine(PNS) levels was measured in Model-IV, III, II and I, respectively. Mean elemental stress(von Mises stress) in the medial pterygoid plate, screw and lateral pterygoid plate regions from highest to lowest was measured in Model-IV, III, II and I, respectively. The maxilla performed outward rotation and tipping movement in all models during the expansion period. Among the distractor positions, the second molar region was found to be the most advantageous one in terms of expansion pattern. Considering the patient’s anatomy and clinical conditions, placing the palatal distractor as posteriorly as possible will result in more effective maxillary expansion.

Maxillary Expansion and Its Effects on Circummaxillary Structures: A Review.

Transverse maxillary discrepancies are the most common. The narrowed upper arch is the most prevalent problem an orthodontist encounter while treating adolescent and adult patients.Maxillary expansion is a technique used to increase the upper arch's transverse dimension to apply forces to widen the upper arch. For young children, a narrow maxillary arch has to be corrected using orthopedic and orthodontic treatments. In an orthodontic treatment plan, it is crucial to update transverse maxillary defeat. There are various clinical manifestations associated with a transverse maxillary deficiency which include a narrow palate, crossbite mainly seen in posteriors (unilateral or bilateral), severe crowding in anterior teeth, and cone-shaped hypertrophy can be seen. Some frequently used therapies for constricted upper arch include slow maxillary expansion, rapid maxillary expansion, and surgically assisted rapid maxillary expansion. Slow maxillary expansion requires light and constant force, whereas rapid maxillary expansion needs heavy pressure for activation. The surgical-assisted rapid maxillary expansion has gradually become popular to correct transverse maxillary hypoplasia. The maxillary expansion has various consequences on the nasomaxillary complex. There are multiple effects of maxillary expansion on the nasomaxillary complex. Mainly, the effect is seen on the mid-palatine suture along with the palate, maxilla, mandible, temporomandibular joint, soft tissue, and anterior and posterior upper teeth. It also affects functions like speech and hearing. Information on maxillary expansion is provided in depth in the following review article, along with its various effects on the surrounding structure.

Evaluation of Masticatory Muscles in Adult Patients with Maxillary Hypoplasia Treated with Surgically Assisted Rapid Maxillary Expansion (SARME): A Retrospective Study.

Aim: The aim of the present study was to investigate modifications in electromyographic activity of temporal and masseter muscles before and after surgically assisted rapid maxillary expansion (SARME) in adult subjects. Materials and Methods: Data from 20 patients with unilateral posterior crossbite were selected retrospectively from the Orthodontics Department of the University of Genoa and the Department of Biomedical Surgical and Dental Sciences of the University of Milan, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico Milan. Inclusion criteria were set as skeletal class I; adult patients (age > 18); good general health; patients with a transverse maxillary deficiency with unilateral posterior crossbite and maxillary constriction ≥ 5 mm; Superficial electromyographic (EMG) examinations at T0 and T1. Exclusion criteria were smoking, metabolic bone diseases (e.g., hyperparathyroidism, vitamin C deficiency), chronic use of corticoids before or during treatment, parafunctional habits (e.g., bruxism), and temporomandibular joint dysfunction. The Shapiro−Wilk test was performed to check whether the data were normally distributed. Differences for each variable before and after SARME were analyzed with a paired t-test (p < 0.05). Results: The statistical analysis demonstrated no statistically significant differences between the EMG values taken before and after SARME regarding the standardized electrical activity of the masticatory muscles (masseter and anterior temporalis (p > 0.05)). Conclusions: Considering the specific conditions of this study, it can be concluded that SARME did not alter the EMG activity of the masseter and temporal muscles. The present study has shown that the masticatory musculature evaluated after approximately 8 months of therapy can adapt well to SARME.

Evaluation of olfactory threshold changes in patients treated with rapid maxillary expansion

Aim: Rapid maxillary expansion (RME) provides an orthopedic effect that solves the problem of transverse deficiency of the maxilla. Moreover, it contributes positively to the functioning of the entire nasopharynx by increasing the cross-sectional area and volume of the nasal tract, thus reducing airway resistance. The aim of this study was to evaluate the changes in olfactory threshold after RME treatment of patients with maxillary transverse deficiency. Methodology: Olfactory threshold and identification tests as well as acoustic rhinometry parameter (Volume1, MCA1, Volume2, MCA2) measurements were conducted for 40 patients (11–16 years) before treatment (T0) and 6 months after (T1) rapid maxillary expansion application. Results: A significant improvement was observed when the olfactory threshold values at T0 (0.96 ± 0.07) and T1 (0.79 ± 0.13) (p &lt; 0.001) were compared. A significant improvement was also observed upon comparing the identification test results at T0 (0.63 ± 0.13) and T1 (0.79 ± 0.11) (p &lt; 0.001). The acoustic rhinometry results showed a significant increase in Volume 1, MCA1, Volume 2 and MCA2 in the right and left nasal cavities after treatment (p &lt; 0.001). Conclusion: In this study, acoustic rhinometry showed that nasal cavity area and volume increased in patients who underwent rapid maxillary expansion therapy. Further, the olfactory functions measured by the olfactory threshold test and identification test improved significantly. How to cite this article: Yıldırım M, Erdur EA, Erdur Ö, Metli ŞN. Evaluation of olfactory threshold changes in patients treated with rapid maxillary expansion. Int Dent Res 2022;12(Suppl.1):90-6. https://doi.org/10.5577/intdentres.435 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

A comparison of transversal changes occurring in the treatment of rapid maxillary expansion with acoustic rhinometry

Aim: The aim of this study was to determine the relationship between cephalometric transversal measurements and nasal patency before and after rapid maxillary expansion (RME) treatment applied to patients with maxillary transversal deficiency. Methodology: The records of 30 patients with maxillary transversal insufficiency and 20 patients without normal dentofacial and nasal symptoms were used. Acoustic rhinometry (MCA1, MCA2, VOL1, VOL2) and cephalometry measurements (JR–JL, MMTI, nasal width) were analyzed before (TO) and six months after (T1) RME. Results: There were no significant differences in age and gender between the groups. After the RME treatment of the patients in the study group, there was a significant increase in the cephalometric measurement (JL–JR, MMTI, nasal width) and acoustic rhinometry measurement parameters (MCA1, MCA2, VOL1, VOL2). Cephalometric measurements showed consistent changes in the patients in the study group, suggesting that RME treatment increased the maxilla’s growth capacity. The postero-anterior cephalometry results improved after RME treatment and approached those of the control group. Conclusion: Significant improvement was observed in the cephalometric transversal measurements after RME treatment. This improvement indicated that RME increases maxillary growth capacity. There was no correlation between cephalometric and acoustic rhinometry. This result may be due to the inability of postero-anterior cephalometry to effectively evaluate the maxilla-related part of the nasal structures. How to cite this article: Metli ŞN, Yıldırım M, Erdur EA, Erdur Ö. A comparison of transversal changes occurring in the treatment of rapid maxillary expansion with acoustic rhinometry. Int Dent Res 2022;12(Suppl.1):97-102. https://doi.org/10.5577/intdentres.434 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.