Transverse Maxillomandibular Discrepancies Research Articles

A study of transverse maxillomandibular discrepancy and dental compensation in early mixed dentition with skeletal Class III malocclusion without posterior crossbite.

To evaluate transverse maxillomandibular discrepancy and dental compensation in first molar areas in 7- to 9-year-old children with skeletal Class III malocclusion without posterior crossbite using cone-beam computed tomography (CBCT). The sample of this retrospective study consisted of 60 children (7 to 9 years old), who were divided into the skeletal Class III malocclusion group (study group, skeletal Class III malocclusion without posterior crossbite, N = 31) and the Class I occlusion group (control group, Class I occlusion with one or two impacted teeth, N = 30). CBCT data were obtained from the database of the Department of Radiology of Hospital of Stomatology, Shandong University. For three-dimensional reconstruction of the head, the dental arch width, basal bone width, and buccolingual inclination angle were measured using MIMICS 21.0 software. Independent-sample t tests were used to compare the two groups. The mean age of the children was 8.18±0.83years. The width of the maxillary basal bone was significantly smaller in the skeletal Class III malocclusion group (59.75 ± 3.14 mm) than in the Class I occlusion group (62.39 ± 3.01 mm) (P < 0.01). The mandibular basal bone width was significantly larger in the skeletal Class III malocclusion group (60.00 ± 2.56 mm) than in the Class I occlusion group (58.19 ± 2.42 mm) (P < 0.01). The difference in the width of the maxillary and mandibular bases in the skeletal Class III malocclusion group (-0.25 ± 1.73 mm) was significantly different from that in the Class I occlusion group (4.20 ± 1.25 mm) (P < 0.01). However, there was no significant difference in the upper or lower dental arch width between the two groups (P > 0.05). The buccal inclination of the maxillary molars in the skeletal Class III malocclusion group (31.4° ± 8.9°) was significantly higher than that in the Class I occlusion group (17.64° ± 7.3°) (P < 0.01), as was the lingual inclination angle of mandibular molars (45.24° ± 8.3° vs. 37.96° ± 10.18°; P < 0.01). Transverse maxillary and mandibular discrepancies in the posterior area and transverse dental compensation were found in the early mixed dentition of patients with skeletal Class III malocclusion without posterior crossbite. This suggests that even in the absence of posterior crossbite, maxillary expansion can be attempted to correct the maxillomandibular transverse discrepancy.

The 'Powerbite' and surgical rapid expansion.

Adults presenting with transverse maxillomandibular discrepancies in Class III skeletal patterns, asymmetries and anterior open bite can be challenging to treatment plan and manage. Therefore, they often necessitate a multidisciplinary approach, with surgical input from the oral and maxillofacial team. It can be difficult to assess how much the maxilla needs to be expanded after surgery in these patients, as the upper and lower teeth cannot be brought into occlusion. We aim to discuss the use of a device we have come to call the 'Powerbite', which is used intra-orally to assess the expansion of the maxilla after surgically assisted rapid palatal expansion (SARPE) and establish when expansion is sufficient to accommodate the mandibular arch. This device is not novel, last described in 1986 in the Journal of Orthodontics.

Non-Surgical Transversal Dentoalveolar Compensation with Completely Customized Lingual Appliances versus Surgically Assisted Rapid Palatal Expansion in Adults-The Amount of Posterior Crossbite Correction.

The aim of this study was to compare the crossbite correction of a group (n = 43; f/m 19/24; mean age 27.6 ± 9.5 years) with surgically assisted rapid palatal expansion (SARPE) versus a non-surgical transversal dentoalveolar compensation (DC) group (n = 38; f/m 25/13; mean age 30.4 ± 12.9 years) with completely customized lingual appliances (CCLA). Arch width was measured on digital models at the canines (C), second premolars (P2), first molars (M1) and second molars (M2). Measurements were obtained before treatment (T0) and at the end of lingual treatment (T1) or after orthodontic alignment prior to a second surgical intervention for three-dimensional bite correction. There was no statistically significant difference (p &gt; 0.05) in the amount of total crossbite correction between the SARPE and DC-CCLA group at C, P2, M1 and M2. Maxillary expansion was greater in the SARPE group and mandibular compression was greater in the DC-CCLA group. Crossbite correction in the DC-CCLA group was mainly a combination of maxillary expansion and mandibular compression. Dentoalveolar compensation with CCLAs as a combination of maxillary expansion and mandibular compression seems to be a clinically effective procedure to correct a transverse maxillo-mandibular discrepancy without the need for surgical assistance.

Clinical applications of miniscrews that broaden the scope of non-surgical orthodontic treatment.

Previously, in the case of malocclusion owing to skeletal discrepancy in adults, the amount of tooth movement was limited since there was no reliable skeletal anchorage device. The only way to treat this case was by repositioning the maxilla and mandible via orthognathic surgery, but most patients are reluctant to undergo surgery owing to the risk and expenses incurred. However, with the current introduction and use of miniscrews as temporary anchorage devices, the entire dental arch can be relocated to a target position without surgery, thus broadening the scope of non-surgical orthodontic treatment compared to the past. For a non-surgical approach to improve skeletal discrepancy, anteroposterior, vertical and transverse displacements of the dental arch are necessary. In this case, the localization of the centre of resistance of the whole arch must precede the appliance design with an appropriate biomechanical design. Especially, in the transverse dimension, the envelope of discrepancy is reportedly narrow, and the tooth movement must accompany the orthopaedic correction involving the midpalatal suture expansion. Recently, in adults with transverse maxillomandibular discrepancy, miniscrew-assisted rapid palatal expansion (MARPE) can be performed. Moreover, compared to surgically assisted rapid palatal expansion, MARPE reduces the cost to the patient and achieves clinically acceptable stable maxillary expansion. In this article, we will discuss the role of total arch movement and MARPE in widening the scope of non-surgical orthodontic treatment, despite the inherent limitations of miniscrews' mechanical aspects.

Stability of bimaxillary surgery involving intraoral vertical ramus osteotomy with or without presurgical miniscrew-assisted rapid palatal expansion in adult patients with skeletal Class III malocclusion.

ObjectiveThe aim of this study was to evaluate the stability of bimaxillary surgery involving bilateral intraoral vertical ramus osteotomy performed with or without presurgical miniscrew-assisted rapid palatal expansion (MARPE) in adult patients with skeletal Class III malocclusion.MethodsA total of 40 adult patients with skeletal Class III malocclusion were retrospectively divided into two groups (n = 20 each) according to the use of MARPE for the correction of transverse maxillomandibular discrepancy during presurgical orthodontic treatment. Serial lateral cephalograms and dental casts were analyzed until 6 months after surgery.ResultsBefore presurgical orthodontic treatment, there was no significant differences in terms of sex and age between groups. However, the difference of approximately 3.1 mm in the maxillomandibular intermolar width was statistically significant (p < 0.001). Two days after surgery, the mandible had moved backward and upward without any significant intergroup difference. Six months after surgery, the maxillary intercanine (2.7 ± 2.1 mm), interpremolar (3.6 ± 2.4 mm), and intermolar (2.0 ± 1.3 mm) arch widths were significantly increased (p < 0.001) relative to the values before presurgical orthodontic treatment in the MARPE group; these widths were maintained or decreased in the control group. However, there was no significant difference in surgical changes and the postsurgical stability between the two groups. No significant correlations existed between the amount of maxillary expansion and postsurgical mandibular movement.ConclusionsMARPE is useful for stable and nonsurgical expansion of the maxilla in adult patients with skeletal Class III malocclusion who are scheduled for bimaxillary surgery.

A New Proposal: a Digital Flow for the Construction of a Haas-Inspired Rapid Maxillary Expander (HIRME).

Maxillary expansion is a common orthodontic treatment used for the correction of posterior crossbite resulting from reduced maxillary width. Transverse maxillomandibular discrepancies are a major cause of several malocclusions and may be corrected in different manners; in particular, the rapid maxillary expansion (RME) performed in the early mixed dentition has now become a routine procedure in orthodontic practice. The aim of this study is to propose a procedure that reduces the patient cooperation as well as the lab work required in preparing a customized Haas-inspired rapid maxillary expander (HIRME) that can be anchored to deciduous teeth and can be utilized in mixed dentition with tubes on the molars and hooks and brackets on the canines. This article thus presents an expander that is completely digitally developed, from the first moment of taking the impression with an optical scanner to the final solidification phase by the use of a 3D printer. This digital flow takes place in a CAD environment and it starts with the creation of the appliance on the optical impression; this design is then exported as an stl extension and is sent to the print service to obtain a solid model of the device through a laser sintering process. This “rough” device goes through a post-processing procedure; finally, a commercial expansion screw is laser-welded. This expander has all the advantages of a cast-metal Haas-type RME that rests on deciduous teeth; moreover, it has the characteristic of being developed with a completely digitized and individualized process, for the mouth of the young patient, as well as being made completely of cobalt-chrome, thus ensuring greater adaptability and stability in the patient’s mouth.

Surgically Assisted Rapid Palatal Expansion to Correct Maxillary Transverse Deficiency.

Background:Transverse maxillomandibular discrepancies are widespread. Treatment is comprised of orthodontic expansion in patients younger than 15 years or by surgically assisted rapid palatal expansion (SARPE) in skeletally mature patients where the possibility of successful orthodontic maxillary expansion decreases as sutures close and resistance to mechanical forces increases.Aim:To present our experience of treating transverse maxillary deficiency using a unique L-shaped osteotomy and to demonstrate stable results.Patients and Methods:32 patients aged between 19 and 54 years exhibiting transverse maxillary deficiency. L-shaped osteotomy was performed laterally from the pterygoid plate posteriorly to above the roots of the second incisive anteriorly continuing with a vertical osteotomy between the lateral incisive and canine teeth toward the horizontal osteotomy. In 18 patients with dysgnathia, bimaxillary surgery was performed one year following the SARPE procedure.Results:Mean transverse maxillary expansion of 6.2mm at the canine incisal and 6.4mm at the first molar occlusal regions were obtained. One year postoperatively results were relatively stable, 5.8mm and 6.2mm respectively. The SARPE procedure resulted in overcoming the maxillary buttress resistance, expansion of the anterior dental arch and bilateral distraction creating bone on both sides of the premaxilla contributing to better alignment of the anterior teeth and superior stability.Conclusions:We conclude that SARPE is an effective and stable method for addressing severe maxillary transverse discrepancy in adults while the unique osteotomy performed allowed for maintaining proper position of the premaxilla and maxillary midline and allowing for division of the newly created bone bilaterally thus resulting in a more stable outcome.

Expansion in the absence of crossbite – rationale and protocol

Transverse maxillomandibular discrepancies are a major component of several malocclusions. Clinically, posterior crossbite is a common and valid indicator of maxillary transverse problems and orthopedic and orthodontic forces are routinely used to correct maxillary transverse deficiency. However, crossbite and transverse discrepancies are not a homologous group but must be viewed as a continuum with varying degree of abnormality. The etiology, diagnostic protocol, rationale, and procedures employed for correcting maxillary transverse discrepancy in the absence of crossbite are discussed in the article.

Surgically assisted rapid palatal expansion: A way to treat transverse maxillary deficiency

Transverse maxillomandibular discrepancies are a major component of several malocclusions. Transverse maxillary discrepancies are routinely corrected in growing patients with appliances that separate the median palatal and associated maxillary sutures. This type of rapid palatal expansion (RPE) is not feasible in adults, however, because of the increasing resistance of the sutures. Surgically assisted RPE is an alternative method that reduces the resistance of the closed midpalatal suture to correct maxillary constriction in an adult. It allows clinicians to achieve effective maxillary expansion in a skeletally mature patient.

Correlation Between Transverse Maxillary Discrepancy And The Inclination Of First Permanent Molars. A Pilot Study

Introduction: the development and growth of craniofacial structures allow some dental alterations to be compensated with maxillary reactions. The purpose of this study was to correlate transversal maxillo-mandibular discrepancy with the bucco-lingual inclinations of first permanent maxillary and mandibular molars in a population aged 10 to 16 years, by means of cone beam computed tomography (CBCT). Methods: the sample included 18 CT scans of patients selected by convenience, prior authorization from the radiographic center and with validation of the Bioethics Committee of Universidad Autonoma de Manizales (Agreement No. 51, 2015). The transverse mandibular and maxillary distance was measured, calculating discrepancy and correlating with the bucco-lingual inclination of first permanent molars. Results: average mandibular transverse distance was higher than maxillary transverse distance (p 5 o ) and the inclination of molars (p < 0.05). There was also moderate correlation in patients with negative maxillary discrepancy (< 5 o ). Conclusion: transverse maxillomandibular discrepancy is related to the bucco-lingual inclination of first permanent maxillary and mandibular molars in two different ways according to discrepancy type—positive or negative—. The reaction of the maxillary is a process that requires more studies to understand the timing and extent of the adaptation

Surgically assisted Maxillo-mandibular transverse expansion

The skeletal correction of transverse maxillary deficiency is difficult via orthodontics and orthopedics after 18 years of age and is successful until the age of approximately 13-15 yearsdepending on the gender of the patient [1, 2]. After the skeletal maturity, orthodontic treatment alone cannot provide stable widening of constricted maxilla. The area of increased skeletal resistance to expansion is indeed not the midpalatal suture, but the pterygomaxillary, zygomatico temporal, zygomatico frontal and zygomatico maxillary [3, 4]. The skeletal mandibular transverse deficiency is a difficult clinical situation to handle by orthodontic means alone. This case report highlights the successful management of transverse maxillo-mandibular discrepancy by combined orthodontic-surgical approach.

Anterior Vertical Osteotomy for Mandibular Narrowing

The management of transverse maxillomandibular discrepancies, clinically known as crossbites, is a controversial and rarely discussed topic in both orthodontic and surgical literature. To evaluate the short-term stability of mandibular narrowing after the combination of anterior vertical symphyseal and bilateral sagittal split osteotomies, a prospective cohort study was completed. Between December 1996 and June 2006, 40 patients underwent mandibular narrowing for the correction of substantial transverse maxillomandibular discrepancies resulting primarily from relative mandibular widening. Stability assessment was done on 26 patients who returned for the final evaluation. Follow-up periods ranged from 5 to 109 months (mean, 18 mo; N = 26). The stability of mandibular narrowing was evaluated by comparison of preoperative clinical assessment, lower dental impression, posteroanterior cephalogram, and occlusographic analysis with studies completed in the immediate postoperative period and at 6 to 12 months. At the short-term time point, mean mandibular location had relapsed 4.7 degrees in 21 patients. Although various methods of mandibular narrowing are well described, very little literature has examined its stability. Using an occlusographic analysis based on angular mandibular movement in a large patient cohort, we were able to demonstrate and quantify, for the first time, the relapse. It occurs in 81% of the patients, with a mean of 4.7 degrees.

Les anomalies maxillomandibulaires du sens transversal chez l’enfant

Transverse maxillomandibular discrepancies are a major component of several malocclusions. They must be prematurely detected and treated. The causes are parafunctional, dysfunctional or kinetic. The different clinical forms encountered are alveolar (endoalveolia) or skeletal (endognathia), which may be associated with a kinetic anomaly. Orthopedic and orthodontic forces are used routinely to correct a maxillary transverse deficiency in a young patient to achieve harmonious growth.

Excessive Rapid Palatal Expansion with Latham Appliance for Distal Repositioning of Protruded Premaxilla in Bilateral Cleft Lip and Alveolus

This article reports a case of bilateral cleft lip and alveolus (BCLA) for which excessive rapid palatal expansion with a Latham appliance was performed for preoperative alignment of the protruded premaxilla. Postoperative changes of maxillary width were investigated with serial plaster casts. A 3-month-old girl presented with complete BCLA in which the premaxilla was markedly protruded. Preoperative alignment of the protruded premaxilla with a Latham appliance was planned to facilitate primary lip repair. The appliance was placed when the patient was 4.5 months old. The necessary palatal expansion was estimated to be 7.0 mm in order to move the premaxilla backward into the ideal position. After palatal expansion and posterior repositioning of the protruded premaxilla, the primary operation, including cheiloplasty and gingivoperiosteoplasty, was performed when the patient was 7 months old. Excessive maxillary expansion might be a cause of transverse maxillomandibular discrepancy. Measurement with serial plaster casts demonstrated that maxillary widths increased from 42.3 mm pretreatment to 49.0 mm after orthopedic treatment but relapsed markedly to 43.5 mm at 3 months after the primary operation. Therefore, the net change of maxillary widths was only 1.2 mm. After alignment of the protruded premaxilla, tension-free soft tissue repairs were performed, and a harmonious alveolar arch was obtained without change in maxillary width. These results indicate that this method is useful for preoperative management of BCLA with protruded premaxilla.

Segmental Osteotomies of the Maxilla

Multiple segment Le Fort I osteotomies provide the maxillofacial surgeon with the capabilities to treat complex dentofacial deformities existing in all three planes of space. Sagittal, vertical, and transverse maxillomandibular discrepancies as well as three-dimensional abnormalities within the maxillary arch can be corrected simultaneously. Accordingly, optimal aesthetic enhancement of the facial skeleton and a functional, healthy occlusion can be realized. What may be perceived as elaborate treatment plans are in reality conservative in terms of osseous stability and treatment time required. The close cooperation of an orthodontist well-versed in segmental orthodontics and orthognathic surgery is critical to the success of such surgery. With close attention to surgical detail, the complication rate inherent in such surgery can be minimized and the treatment goals achieved in a timely and predictable fashion.