Palatal Expansion Research Articles

Dimensiones tomográficas para la instalación de miniimplantes de expansión rápida maxilar en diferentes grupos de edad

Objective: The purpose of the research was to com-pare the dimensions of the upper jaw between different age groups for the installation of mini-implants for rapid maxillary expansion. Materials and Methods: The study was descriptive, retroprospective and observational. Cone beam computed tomography was used for the evaluation of 30 patients between 7 and 56 years of age, divided into three groups, ten up to 14 years, ten from 15 to 30 years, and ten from 31 years and older. The premolar and molar regions were selected for the measurement of the maxilla in the coronal plane, both bone and soft tissue. To compare the measurements, the Kruskal Wallis and Mann-Whitney U tests were used. Results: No statistically significant differences were found between the groups. The thicknesses of the bone tissue decreased from the first premolar to the second molar from 9.48 +/-3.71 mm to 5.40 +/-2.80 mm respectively, while the soft tissue thicknesses were more homogeneous with measurements of 0.56 +/-0.74 mm to 2.76 +/- 2.42 mm. Conclusions: The dimensions of the bone and soft tis-sue of the upper jaw, evaluated vertically for the installa-tion of mini-implants, were similar in all the age groups studied, with larger dimensions in men than in women at the premolar level. The dimensions of the maxilla for the palatal miniimplants were close to 9 mm in bone tissue and 3 mm of soft tissue at the level of premolars and 5 mm in hard tissue with 1 mm of soft tissue at the level of molars. Keywords: Palatal expansion technique; Dental im-plants; Mini implants; Maxilla; Cone-beam computed to-mography; Age groups

Comparison of maxillary transversal changes between auxiliary beta-titanium expansion arch and miniscrew-assisted rapid palatal expansion.

This study compared buccal bone thickness, dental inclinations and maxillary transverse width dimensions changes between auxiliary beta-titanium expansion arch (AEA) and miniscrew-assisted rapid palatal expansion (MARPE). The sample consisted of 29 patients, aged between 18 and 40 years, with transverse maxillary deficiency and treated without extractions, divided into two groups: group AEA: comprised 13 individuals (initial mean age: 29.23 ± 9.13 years) treated using auxiliary beta-titanium expansion arch; group MARPE: comprised 16 patients (initial mean age: 24.92 ± 7.60 years) treated with miniscrew-assisted rapid palatal expansion. Buccal bone thickness, dental inclinations and transverse width dimensions (dental, nasal base and jugular) were measured in cone-bean computed tomographies at pre- and post-treatment stages. The variables were compared using the independent t-test. The buccal bone thickness was similar for both groups at the post-treatment stage. The second premolars were significantly more buccal inclined in the AEA group and the right maxillary first molars in the MARPE group. The intercanine and intermolar distances were statistically significantly greater in the MARPE group. Changes in dental arch transverse dimensions were significantly greater for the MARPE group. Both treatment protocols corrected the maxillary transverse discrepancy; however, MARPE provided greater correction.

Convolutional neural network-assisted diagnosis of midpalatal suture maturation stage in cone-beam computed tomography

ObjectivesThe selection of treatment for maxillary expansion is closely related to the calcification degree of the midpalatal suture. A classification method for individual assessment of the morphology of midpalatal suture in cone-beam computed tomography (CBCT) is useful for evaluating the calcification degree. Currently, convolutional neural networks (CNNs) have been introduced into the field of oral and maxillofacial imaging diagnosis. This study validated the ability of CNN models in assessing the maturation stage of the midpalatal suture. MethodsThe existing CNN model ResNet50 was trained to locate the CBCT transverse plane which contained a complete midpalatal suture. ResNet18, ResNet50, RessNet101, Inception-v3, and Efficientnetv2-s models were trained to evaluate the midpalatal suture maturation stage. Multi-class classification metrics, accuracy, recall, precision, F1-score, and area under the curve values from the receiver operating characteristic curve were used to evaluate the performance of the models, and gradient-weighted class activation map technology was utilised to visualise five midpalatal suture maturation stages for each model. ResultsResnet50 demonstrated an accuracy of 99.74 % in identifying the transverse plane that contained the complete midpalatal suture. The highest accuracies achieved on the two-stage, three-stage, and five-stage maturation classification tests were 95.15, 88.06, and 75.37 %, all of which exceeded the average accuracy of three experienced orthodontists. ConclusionsThe CNN model can locate the plane of the midpalatal suture in CBCT images and can assist clinicians in assessing the maturation stage of the midpalatal suture to select the means of maxillary expansion. Clinical significanceThe application of artificial intelligence on CBCT midpalatal suture plane localisation and maturation stage evaluation enhances diagnostic and treatment efficiency and accuracy of individual assessment of midpalatal suture calcification degree. Additionally, it assists the clinical palatal expansion technique in achieving ideal results.

A Retrospective Histological Study on Palatal and Gingival Mucosa Changes during a Rapid Palatal Expansion Procedure.

The most common inflammatory reactions in the oral mucosa are found at the gingival level. The treatment of these inflammations requires, first of all, the removal of the causative factor; often, this maneuver is sufficient. The aim of this retrospective study was to evaluate clinical and histopathological changes that occur in terms of gingival and palatal mucosa enlargement during palatal expansion treatment and their evolution during treatment. Twenty-five (n = 25) research participants, aged between thirteen and twenty-six years old, were examined in this retrospective study. At the end of the treatment, fragments of tissue from the affected level were obtained via incisional biopsy and sent to the histopathology laboratory for a specialized examination. The changes identified were specific to mechanical traumatic injuries, thus excluding hyperplasia from other etiologies (infectious, tumoral, or non-mechanical traumatic). The examined fragments showed hyperplasia. The histopathological examination revealed the mechanical character of the lesion, strengthening the causal relationship between the insertion of the expander and the occurrence of hyperplasia of the palatal mucosa. The type of palatal expander influenced the degree of inflammation, with the severity of hyperplasia being more pronounced in the case of mini-implant-anchored rapid palatal expander (MARPE) usage than in the case of tooth-borne rapid palatal expander (RPE) usage. The analysis of the distance between the expander and the palatal mucosa did not provide conclusive results; the incidence and severity of the reaction were variable in patients with the same distance between the expander and the palatal or gingival mucosa.

Orthodontics and Obstructive Sleep Apnea: A Comprehensive Study of Airway Effects and Treatment Approaches

This comprehensive review explores the intricate relationship between orthodontics and obstructive sleep apnea (OSA) over the past decade, with a particular focus on studies conducted in the United Kingdom. The paper synthesizes findings regarding the airway effects of orthodontic interventions, the role of various orthodontic appliances, and their effectiveness in managing OSA symptoms. The literature review encompasses investigations into changes in airway dimensions, soft tissue structures, and breathing patterns resulting from orthodontic treatments. The effectiveness of appliances like mandibular advancement devices and palatal expanders is critically examined. The challenges and limitations in studying this relationship are discussed, addressing issues related to study design, sample sizes, and variability in orthodontic techniques.

Torque changes of anchorage units in preadolescent patients treated with a digitally designed tooth-borne expander anchored to deciduous vs. permanent molars.

To compare the effects on permanent or deciduous anchorage dental units in patients treated with a digitally designed palatal expander. Inclusion criteria were the following: presence of maxillary transverse deficiency, no previous orthodontic treatment, no extractions, absence of agenesis, congenital pathologies and cranio-maxillofacial malformations. Twenty patients (11 males, 9 females, 11 ± 1.8 years) received a digitally designed and metal printed palatal expander anchored on first permanent molars and 1 activation per day for 30 days (Group 1). Twenty-one patients (12 males, 9 females, 8.6 ± 1.4 years) received a digitally designed and metal printed palatal expander anchored on second deciduous molars and 2 activations per day for 14 days (Group 2). Digital intraoral scans were taken before expansion and after device removal, and torque and the palatal transverse diameter were digitally measured. The FDI notation was used to indicate each tooth CONCLUSION: Less dental torque augmentation was produced in Group 2. Significant intragroup differences over time were found in Group 1 considering the torque of teeth 1.6, 1.4, 1.3, 2.1, 2.4, 2.5, 2.6. Significant differences between groups were found regarding the longitudinal change in torque of teeth 1.5, 2.4 and 2.5. Significant intragroup differences over time were found in both groups considering all transverse diameter parameters. No significant differences were found between groups in the transverse diameter modifications over time. Less dental torque augmentation was produced in Group 2.

Efficacy of the rapid maxillary expansion with a modified acrylic splint palatal expander: A randomized clinical trial

Aim: This prospective randomized clinical trial aimed at analyzing the skeletal effects of this modified acrylic splint palatal expander (MASPE) used for maxillary transversal deficiency treatment in mixed dentition. Methods: Eligibility criteria included maxillary transverse deficiencies in children between 7 and 10 years of age. Eighteen individuals who met the inclusion criteria and reached the end of treatment were evaluated (mean age of 8.66 years old) and randomly assigned to be submitted to rapid maxillary expansion with either the MASPE experimental device or a well-known tooth-borne expander (control group). CBCT scans taken before expansion and at the end of the retention period were evaluated. The palatal area was calculated, and the length of expansion was measured. Treatment changes were analyzed using paired t-tests, whereas independent t-tests were used to compare the two groups. Results: There were statistically significant (p<0.05) increases in maxillary width at the suture level in both groups, with a substantial increase in the palatal area. The group differences were not significant. Conclusions: MASPE showed good efficiency and skeletal effects but no superiority over the control group. Keywords: Maxillary expansion; Mixed Dentition; Orthodontics; Orthopedics

Long-term evaluation of soft-tissue changes after miniscrew-assisted and conventional rapid palatal expansion using voxel-based superimposition of cone-beam computed tomography scans

This study aimed to evaluate the soft-tissue changes in the long-term after miniscrew-assisted rapid palatal expansion (MARPE) and conventional rapid palatal expansion (RPE) appliances compared with a matched control group using voxel-based superimposition of cone-beam computed tomography (CBCT) scans. A total of 180 CBCTs for 60 patients at 3-time points were evaluated: pretreatment (T1), postexpansion (T2), and posttreatment (T3) for 3 groups: (1) MARPE, (2) RPE, and (3) controls (time-period T1 to T3: MARPE, 2 years 8 months; RPE, 2 years 9 months; control, 2 years 7 months). The voxel-based superimposition technique was used to superimpose the CBCT scans, after which the soft-tissue surfaces were extracted from the superimposed T1-CBCT, T2-CBCT, and T3-CBCT scans. Nine landmarks were identified on the CBCT scans: nasion, A-point, pogonion, right and left alar base, right and left zygoma, and right and left gonion. The coordinates of the 9 parameters were obtained in the x-axis, y-axis, and z-axis for the CBCT scans and subjected to statistical analyses. The changes in the soft-tissue surfaces were also evaluated by color-coded maps for short-term (T2) and long-term (T3) changes. The mean changes from T1 to T2 and T1 to T3 were tested against no change within the groups by paired t test, and the mean changes among the 3 groups were compared with analysis of variance F test with Tukey's Honest significant difference used for adjusting P values for multiple testing. In the short term, both MARPE and RPE led to a significant downward movement of pogonion, left gonion, and lateral movement of the right and left alar base compared with controls at T2 (P<0.05). In addition, MARPE led to a significant downward movement of right gonion than controls at T2 (P<0.05). Moreover, RPE led to a significant downward and forward movement of A-point and downward movement of the right and left alar base than controls at T2 (P<0.05). However, in the long-term, there were no significant differences in the soft-tissue changes among the MARPE, RPE, and control groups. MARPE and RPE do not lead to significant soft-tissue changes in the long term when compared with controls.

Digital workflow for mini-implant–assisted rapid palatal expander fabrication–a case report

BackgroundNon-surgical mini-implant assisted rapid palatal expansion, or midfacial skeletal expansion, is a paradigm-shifting concept that in recent years has expanded the envelope of orthopedic movement in the transverse direction for adult patients. Although adding mini-screws to a rapid palatal expander is not complicated, accurate and successful expansion strongly depends on the device’s position and its relation to the resisting structures of the maxillofacial complex.Case presentationThis article presents a digital workflow to locate the optimal position of the Midfacial Skeletal Expander (MSE) device in a CBCT-combined intraoral scan file and describes how to transfer the MSE position intra-orally with properly sized bands during the device fabrication. The complete digital workflow of MSE fabrication and its application for a Class III orthognathic surgical case is presented in detail.ConclusionsThis report describes a completely digital process that can accurately position the MSE device according to the orientation and morphology of maxillary basal bone, which is crucial in adult cases demand maxillary expansion.

Simulation of SMA-based engineering applications considering large displacement and rotation, thermomechanical coupling and partial phase transformation

Shape memory alloys (SMAs) undergo large recoverable deformation due to their inherent diffusionless martensitic phase transformation. Two factors need to be taken into account to incisively emulate the behaviour of SMA based structures: (i) consideration of large displacement and rotation (LDR) effect, and (ii) capturing the consequence of transformation induced material level coupling. In this study, both these effects are apprehended by extending the infinitesimal strain-based constitutive model of SMA as proposed by Lagoudas et al. (2012), assuming small elastic strain but with finite inelastic strain. To preclude any spurious stress generation out of large rotation, the Jaumann stress rate is used, and incremental objectivity for finite rotation between two successive time instants is conserved by rotating the strain increment and spin tensor to the rotation-independent mid-point configuration following Hughes–Winget (Hughes and Winget, 1980) algorithm. In addition, the contribution of thermoelastic and latent heat evolved during transformation is taken into consideration in the thermal equilibrium equation. Moreover, the effect of partial phase transformation yielding minor hysteresis loop has also been captured. The equilibrium equation is expressed in the current configuration following the Updated Lagrangian formulation. The mechanical and thermal equilibrium equations are solved concurrently in block matrix form using the Newton–Raphson (NR) iterative technique, considering the coupling terms resulting from the phase transformation. The efficacy and robustness of the developed finite element model are corroborated through various practical applications of SMA-based members, e.g., SMA ring, SMA-actuated beam, morphing of corrugated airfoil, orthodontic palatal expander, compliant gripper, undergoing LDR while subjected to different thermomechanical loading conditions. The combined effects of LDR along with thermomechanical coupling yield a stiffening behaviour during loading and sluggish response at the time of thermal recovery.

Long-term efficacy and stability of miniscrew-assisted rapid palatal expansion in mid to late adolescents and adults: a systematic review and meta-analysis

BackgroundThe purpose of this study is to investigate the long-term efficacy and stability of Miniscrew-assisted Rapid Palatal Expansion (MARPE), including its primary outcomes, namely the nasomaxillary complex transverse skeletal and dental expansion, and related secondary outcomes.MethodsElectronic databases and manual literature searches, up to October 31, 2022, were performed. The eligibility criteria were the following: studies on patients with transverse maxillary deficiency treated with MARPE in adults and adolescents over 13.5 years of age.ResultsUltimately, twelve articles were included in the analysis, one prospective and eleven retrospective observational studies. Five studies showed a moderate risk of bias, while the remaining seven studies were at a serious risk of bias. The GRADE quality of evidence was very low. MARPE is an effective treatment modality for transverse maxillary deficiency (mean success rate: 93.87%). Patients showed increased mean in the skeletal and dental transverse expansion. The basal bone composition, mean alveolar bone and mean dental expansion accounted for 48.85, 7.52, and 43.63% of the total expansion, respectively. There was a certain degree of skeletal and dental relapse over time. MARPE could also cause dental, alveolar, and periodontal side effects, and have an impact on other craniofacial bones, upper airway, and facial soft tissue.ConclusionsMARPE is an effective treatment for transverse maxillary deficiency, with a high success rate and a certain degree of skeletal and dental relapse over time.

The short- and long-term changes of upper airway and alar in nongrowing patients treated with Mini-Implant Assisted Rapid Palatal Expansion (MARPE): a systematic review and meta-analysis

ObjectiveThis study aims to assess the short- and long-term changes in the upper airway and alar width after mini-implant -assisted rapid palatal expansion (MARPE) in nongrowing patients.MethodsFive electronic databases (PubMed, Scopus, Embase, Web of Science, and Cochrane Library) were searched up to 2 August, 2023 based on the PICOS principles. The main outcomes were classified into three groups: 1) nasal cavity changes, 2) upper airway changes and 3) alar changes. The mean difference (MD) and 95% confidence intervals (CI) were used to assess these changes. Heterogeneity tests, subgroup analyses, sensitivity analyses, and publication bias were also analyzed.ResultOverall, 22 articles were included for data analysis. Nasal cavity width (WMD: 2.05 mm; 95% CI: 1.10, 3.00) and nasal floor width (WMD: 2.13 mm; 95% CI: 1.16, 3.11) increased significantly. While palatopharyngeal volume (WMD: 0.29 cm3, 95% CI: -0.44, 1.01), glossopharyngeal volume (WMD: 0.30 cm3, 95% CI: -0.29, 0.89) and hypopharyngeal volume (WMD: -0.90 cm3; 95% CI: -1.86, 0.06) remained unchanged, nasal cavity volume (WMD: 1.24 cm3, 95% CI: 0.68, 1.81), nasopharyngeal volume (MD: 0.75 cm3, 95% CI: 0.44, 1.06), oropharyngeal volume (WMD: 0.61 cm3, 95% CI: 0.35, 0.87), and total volume of the upper airway (WMD: 1.67 cm3, 95% CI: 0.68, 2.66) increased significantly. Alar width (WMD: 1.47 mm; 95% CI: 0.40, 2.55) and alar base width (WMD: 1.54 mm; 95% CI: 1.21, 1.87) also increased.ConclusionMARPE can increase nasal cavity width, nasal cavity volume, nasopharyngeal volume and oropharyngeal volume for nongrowing patients, but has no significant effect on hypopharyngeal volume. In addition, the alar width also increased. However, the studies included in this meta-analysis were mainly retrospective, nonrandomized and small in number, so the findings should be interpreted with caution and high-quality RCTs need to be studied.

Evidences From Systematic Reviews Regarding Miniscrew-Assisted Rapid Palatal Expansion (MARPE) Approach In Orthodontics

Background. Miniscrew-assisted rapid palatal expansion (MARPE) has been considered as relatively novel and effective method of orthodontic treatment, but the discussion is still ongoing regarding effectiveness of MARPE for different age population groups, while also in comparison with surgically assisted rapid palatal expansion or conventional rapid maxillary expansions, since evidences available for MARPE is mostly of insufficient quality.&#x0D; Objective. To collect and represent evidences of MARPE treatment outcomes in orthodontics based on the data available within systematic reviews.&#x0D; Materials and Methods. Search was provided via PubMed Central, Web of Science and Scopus databases, while also within Cochrane Library. Only systematic reviews written in English were considered for analysis. Primary outcomes such as success rate (percentage of cases, where required maxillary width was achieved) and maxillary expansion rate in means of midpalatal split, dental intermolar width, skeletal and dentoalveolar expansion, palatal suture opening, palatal width measured in millimeters or percentage were tabulated and analyzed. Secondary outcomes were presented in descriptive manner &#x0D; Results. Overall 12 systematic reviews were enrolled into study group of targeted publications. Among these 12 systematic reviews primary outcomes were extracted from 8 of them, while rest 4 systematic reviews were used for analysis of secondary outcomes. Succes rate of MARPE varied in the range of 82.8-100%, while intermolar width increase after MARPE treatment – in the range of 4.79-6.55 mm. &#x0D; Conclusion. Considering data available within systematic reviews MARPE approach seems to be reliable orthodontic treatment option, which help to gain significant increase for skeletal and dental intermolar width among patients with maxillary transverse deficiency. Such treatment strategy provides better results than conventional rapid maxillary expansion and lesser periodontal negative consequences compare to surgical-assisted rapid palatal expansion, even though quality of data supporting these statements are insufficient and debatable.

Finite Element Analysis Model for Assessing Expansion Patterns from Surgically Assisted Rapid Palatal Expansion.

Surgically assisted rapid palatal expansion (SARPE) was introduced to release bony resistance to facilitate skeletal expansion in skeletally mature patients. However, asymmetric expansion between the left and right sides has been reported in 7.52% of all SARPE patients, of which 12.90% had to undergo a second surgery for correction. The etiologies leading to asymmetric expansion remain unclear. Finite element analysis has been used to evaluate the stress associated with SARPE in the maxillofacial structures. However, as a collision of the bone at the LeFort I osteotomy sites occurs only after a certain amount of expansion, most of the existing models do not truly represent the force distribution, given that the expansion amount of these existing models rarely exceeds 1 mm. Therefore, there is a need to create a novel finite element model of SARPE that could perform a clinically required amount of expander activation for further analysis of the expansion patterns of the hemimaxillae in all three dimensions. A three-dimensional (3D) skull model from cone beam computed tomography (CBCT) was imported into Mimics and converted into mathematical entities to segment the maxillary complex, maxillary first premolars, and maxillary first molars. These structures were transferred into Geomagic for surface smoothing and cancellous bone and periodontal ligament creation. The right half of the maxillary complex was then retained and mirrored to create a perfectly symmetrical model in SolidWorks. A Haas expander was constructed and banded to the maxillary first premolars and first molars. Finite element analysis of various combinations of buccal osteotomies at different angles with 1 mm clearance was performed in Ansys. A convergence test was conducted until the desired amount of expansion on both sides (at least 6 mm in total) was achieved. This study lays the foundation for evaluating how buccal osteotomy angulation influences the expansion patterns of SARPE.

Posterior Palatal Expansion via Subnasal Endoscopy (2PENN) for Maxillary Deficiency: A Pilot Study.

Surgically assisted rapid palatal expansion (SARPE) addresses transverse maxillary deficiency, a known contributor to nasal obstruction. The purpose of this study was to assess the feasibility, preliminary outcomes, and safety of posterior palatal expansion via subnasal endoscopy (2PENN), a modified SARPE procedure, aimed at achieving anterior and posterior maxillary expansion. This prospective case series included consecutive adult patients with findings of transverse maxillary deficiency that underwent the 2PENN procedure from 4/2021 to 4/2022. Patients completed pre- and post-operative clinical evaluations, Nasal Obstruction and Septoplasty Effectiveness (NOSE) questionnaires, and computed tomography (CT), with measures including expansion at the level of the posterior nasal spine (PNS), first maxillary inter-molar distance (IMD), and anterior nasal spine (ANS). The cohort (N = 20) was middle-aged (39 ± 11 years), predominantly male (80%), and overweight (BMI 28 ± 4 kg/m2 ). The majority (85%) of patients had sleep breathing issues, of which 10 (59%) had polysomnography-confirmed obstructive sleep apnea (OSA). Full anterior-posterior separation of the mid-palatal suture line was evident on all post-operative CT scans, with mean expansion at the PNS of 3.6 ± 1.3 mm, IMD of 6.1 ± 1.6 mm and ANS of 7.0 ± 1.6 mm (p < 0.001). Following surgery, mean NOSE scores improved from 57 ± 23 to 14 ± 13 (p < 0.001). One patient required maxillary antrostomy for post-operative sinusitis. 2PENN is an effective and safe technique for achieving both anterior and posterior maxillary expansion in patients with transverse maxillary deficiency. Further study is warranted to better understand the effect of 2PENN in patients with OSA, particularly as it relates to improving pharyngeal patency. 4 Laryngoscope, 134:1970-1977, 2024.

Is There a Difference in Mid-Palatal Suture Density after Rapid Maxillary Expansion, Surgically Assisted Rapid Maxillary Expansion, and Miniscrew-Assisted Rapid Palatal Expansion? A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to evaluate the density of the midpalatal suture (MPS) of individuals with maxillary expansion (rapid maxillary expansion, RME), surgically assisted rapid maxillary expansion (SARPE), and miniscrew-assisted rapid palatal expansion (MARPE) through computed tomography. An electronic search was performed in four databases, MEDLINE via PubMed, SCOPUS, Web of Science, and Cochrane Central Register of Controlled Trials (CENTRAL) in February 2023 and updated in April 2023, using previously established search strategies. Studies were retrieved without restrictions in terms of data, language, or publication status. The risk of bias assessment was based on a quality assessment tool for before-and-after studies. Ten studies were included in our systematic review, and nine studies were included for our quantitative analysis. The analyses were performed by subgroup according to the evaluation of the region, anterior, middle, and posterior, including the three types of treatment: RME, SARPE, and MARPE. Heterogeneity was high for the three regions (anterior 95%, medium 97%, and posterior 84%) and a statistical difference was found in two of the three regions (anterior p = 0.06, medium p = 0.031, and posterior p &lt; 0.001). There is not enough evidence to state that the MPS density is different after 6 months of RME in the anterior and middle regions; the bone density values for SARPE and MARPE suggest that 6 or 7 months after expansion, there is still no bone density similar to the initial one in the three regions.

Three-dimensional evaluation of dentopalatal changes after rapid maxillary expansion in growing children

In growing children with transverse malocclusion problems, various types of rapid maxillary expanders (RMEs) have been effectively used in skeletal and dental expansions. We evaluated 3-dimensional dentopalatal changes in growing children who underwent maxillary expansion using RMEs and bonded RMEs. We investigated dentopalatal changes in 20 patients treated with bonded RMEs, 19 with RMEs, and 38 control patients. Dental plaster models before and after expansion were scanned 3-dimensionally and superimposed to evaluate transverse expansion, expansion ratio, angular expansion, and palatal expansion height ratio. Using bonded RMEs, similar anterior and posterior dental expansions were achieved with an efficiency of 69%-76% (expansion ratio), and palatal soft-tissue expansion occurred more apically in the posterior area (palatal expansion height ratio, 1.00) than in the anterior area (palatal expansion height ratio, 0.64). Using RMEs, a larger posterior dental expansion was achieved, with an efficiency of 106%-117% (expansion ratio), than anterior dental expansion (55%-60%), and palatal soft-tissue expansion occurred more apically in the posterior area (palatal expansion height ratio, 0.99) than anterior area (palatal expansion height ratio, 0.23). Dental expansions in the anterior and posterior areas were similar using bonded RMEs, whereas the posterior dental expansions were larger than those of the anterior area using RMEs. The entire palatal soft-tissue slope expanded in the posterior area, whereas the occlusal part expanded inthe anterior area using RMEs and bonded RMEs.

Stress distribution and displacement with four different types of MARPE on craniofacial complex: A three-dimensional finite element analysis

Various designs of mini-implants assisted rapid palatal expander (MARPE) appliances can impact treatment effectiveness through their biomechanical effects. The purpose of the study was to study the stress distribution and displacement with four different designs of the MARPE appliance on the craniofacial complex. A 3D finite element model of the craniofacial complex was created from CBCT DICOM data, comprising four distinct groups. Each group consisted of one 4-hole expansion screw positioned between the second premolar and first molar in all models. Group 1 used four single-cortical mini-implants (1.5×8mm) engaging only the palatal cortex. Group 2 employed four mini-implants (1.5×11mm) engaging both the palatal and nasal cortices. Group 3 had monocortical implants on the palatal slopes, while Group 4 was similar to group 3 with implants in the acrylic wings. Comparisons between groups were made for anchorage (groups 1 and 2), mini-implant position (groups 1 and 3) and surface effect (groups 3 and 4). Von Mises stresses and displacements at various skeletal and dental points were evaluated using ANSYS software. The highest stresses were observed in the maxillary, pterygoid and zygomatic bones, as well as in the mid- palatal suture in all four groups. Downward and forward rotation of the craniofacial complex was noted. Group 2 showed greater skeletal expansion than group 1. Among groups 1 and 3, group 3 showed a better stress distribution. Group 4 showed less dentoalveolar rotation than group 3. The MARPE appliances had an impact on the craniofacial complex with stresses on the mid-palatal suture, maxillary bone, pterygoid bones and anterior teeth. Clockwise rotation of the maxilla, zygomatic bones and dentition was noted, while the pterygoid bones and pterygoid suture were displaced backwards. MARPE with bicortical anchorage produces better skeletal expansion. Placing implants on the palatal slopes with acrylic wings results in better skeletal expansion with less clockwise rotation of the dentition.

Antibiotic prophylaxis and surgical site infections in orthognathic surgery – a retrospective analysis

BackgroundThis study was conducted to determine surgical site infection (SSI) rates and potential risk factors as well as to evaluate antibiotic prophylaxis in orthognathic surgery.MethodsThis retrospective observational study included patients who received orthognathic surgery. SSIs and their management were assessed for up to one year post-operatively. The applied antibiotic regime and other possible influencing factors (smoking, age, site of infection, drainage, duration of surgery, displacement distances, craniofacial malformations) were assessed.ResultsIn total 291 patient met the inclusion criteria (56.7% female). The mean age at surgery was 25.5 ± 8.5 years. Fifty-four patients (18.6%) were diagnosed with a craniofacial malformation. Relevant previous surgeries were documented in about one quarter of included patients (n = 75). Ninety-two percent of patients (n = 267) received intraoperative single-dose antibiotic prophylaxis. Surgical site infections occurred in 12.4% (n = 36) of patients. There was a significant association between postoperative infections and type of surgery (P = .037) as well as type of drainage (P = .002). Statistical analyses also revealed a higher prevalence of smokers (P = .036) and previous surgically assisted rapid palatal expansion (SARPE) (P = .018) in the infection group. Furthermore, no significant relationships were observed between postoperative infections and various co-factors (i.e. antibiotic regime, age at surgery, gender, associated craniofacial malformations, surgery duration, displacement distances, mandibular setback vs. advancement).ConclusionLow rates of SSIs occurred following an intraoperative single-dose antibiotic regime. None of the SSIs had a significant effect on the final surgical outcome. Present data do not warrant escalation of the antibiotic regimen. Postoperative smoking and capillary drainage should be avoided.

Effects of SARPE and MISMARPE on correction of transverse maxillary deficiency: A preliminary comparative evaluation.

The present study was designed to compare, on cone-beam computed tomography imaging, the skeletal and dental effects of the SARPE (Surgically assisted rapid palatal expansion) and MISMARPE (Minimally Invasive Surgical and Miniscrew-Assisted Rapid Palatal Expansion) techniques. The sample of adult patients with transverse maxillary deficiency (TMD) was divided into two groups, and scans were obtained preoperatively (T0) and immediately after completion of expansion (T1). The posterior and anterior linear transverse distances of the maxilla and the angulation of the maxillary first molars were evaluated. The data were entered into a generalized estimating equations model to verify the postoperative effects of the different techniques. None of the techniques caused any appreciable change in the angulation of the molars. The skeletal changes were similar, with significantly greater gains in the nasal fossa and intermaxillary distance when using the MISMARPE. The technique can be an effective and lower morbidity alternative to SARPE.