Miniscrews position for a tissue bone borne palatal C-expander affects the displacement pattern of nasomaxillary complex: a finite element study.

This study aimed to evaluate the difference in expansion patterns based on the position of miniscrews for a tissue-bone-borne palatal C-expander using a finite element method. Ten expansion models were examined, each representing a different position of miniscrews on the palate. Models A and B had miniscrews symmetrically placed 7 mm and 15 mm below the cementoenamel junction (CEJ), respectively. Models C to J had miniscrews positioned in a triangular manner at 7 mm and 15 mm below CEJ. Stress, displacement, angular changes of the bone and teeth, and changes in the nasomaxillary complex were measured using elastoplastic behavior models through static-nonlinear simulation employing an implicit method. The anterior and posterior parts of paramidpalatal suture area were identified as ANT, TPS-M, and TPS-L, and their ratio was assessed. Model A, which featured three miniscrews located 7 mm below the CEJ, exhibited the least molar inclination and the smallest amount of skeletal expansion. Model I, with two miniscrews placed between the first and second molars, demonstrated the greatest lateral displacement at point N on the nasal cavity wall, along with the smallest ratio of ANT to TPS-M or TPS-L. This finding suggests that the posterior expansion of the palate in relation to the anterior expansion was maximized. The results of this study indicate that strategic positioning of miniscrews is effective in achieving various expansion patterns based on the targeted correction areas within the nasomaxillary complex.

Bio-Exercise (BioEx) - A biocreative orofacial myofunctional therapy: preliminary cephalometric study and clinical application.

OBJECTIVE: To introduce newly structured and developed orofacial myofunctional therapy (OFMFT) protocols named Bio-Exercise (BioEx), and evaluate the treatment effect of this method, using lateral cephalometric analysis on malocclusion with low tongue posture in young patients. METHODS: A retrospective preliminary study was performed using orthodontic records from 28 patients (mean age of 8.41±1.45-year-old, 13 males, 15 females) treated with BioEx therapy using tongue elevators for 18.14±9.04 months (range: 6 to 37 months). Pretreatment (T0) and post-BioEx therapy (T1) lateral cephalograms were subsequently analyzed for tongue posture changes by linear, anteroposterior and vertical measurements. The data were analyzed by paired t-test, considering a 5% significance level. RESULTS: The tongue length (TGL) and tongue height (TGH) increased statistically significant between T0 and T1. The decrease of the dorsum of the tongue perpendicular to the palatal plane (Td-PP value) was statistically significant. The increase of the tip of the tongue perpendicular to the pterygomaxillary vertical line (TT-PMV) was not statistically significant. CONCLUSIONS: These preliminary cephalometric results indicate that BioEx can be an effective OFMFT modality in increasing the tonicity of the tongue muscles to establish more normalized tongue position at rest.

Split orthodontic airway plate: An innovation to the utilization method of conventional orthodontic airway plate for neonates with Robin sequence.

Since the emergence of neonatal infant orthodontics for treatments of cleft lip and palate with or without Robin sequence (RS) in Europe in the 1950s, advancements in design and scope of its application have been remarkable. As the first institution to adopt orthodontic airway plate (OAP) treatment in the United States in 2019, we saw a need for innovation of the original design to streamline the most labor-intensive and time-consuming aspects of OAP utilization. A solution is introduced using a systematic split expansion mechanism to re-size the OAP periodically to accommodate the neonate's maxillary growth. To date, seven RS patients have received this modified treatment protocol at our institution. Each patient completed full treatment using only one OAP. This innovative utilization method is aptly named the split orthodontic airway plate (S-OAP). Details of the S-OAP and its modifications from conventional OAP are reported.

Bio-Exercise (BioEx) - A biocreative orofacial myofunctional therapy: preliminary cephalometric study and clinical application

ABSTRACT Objective: To introduce newly structured and developed orofacial myofunctional therapy (OFMFT) protocols named Bio-Exercise (BioEx), and evaluate the treatment effect of this method, using lateral cephalometric analysis on malocclusion with low tongue posture in young patients. Methods: A retrospective preliminary study was performed using orthodontic records from 28 patients (mean age of 8.41±1.45-year-old, 13 males, 15 females) treated with BioEx therapy using tongue elevators for 18.14±9.04 months (range: 6 to 37 months). Pretreatment (T0) and post-BioEx therapy (T1) lateral cephalograms were subsequently analyzed for tongue posture changes by linear, anteroposterior and vertical measurements. The data were analyzed by paired t-test, considering a 5% significance level. Results: The tongue length (TGL) and tongue height (TGH) increased statistically significant between T0 and T1. The decrease of the dorsum of the tongue perpendicular to the palatal plane (Td-PP value) was statistically significant. The increase of the tip of the tongue perpendicular to the pterygomaxillary vertical line (TT-PMV) was not statistically significant. Conclusions: These preliminary cephalometric results indicate that BioEx can be an effective OFMFT modality in increasing the tonicity of the tongue muscles to establish more normalized tongue position at rest.

RESUMO Objetivo: Introduzir protocolos de terapia miofuncional orofacial (TMO) recém-estruturados e desenvolvidos, denominados Bio-Exercise (BioEx), e avaliar o efeito do tratamento com esse método, usando análise cefalométrica em radiografias laterais de jovens com má oclusão e postura baixa da língua. Métodos: Foi realizado um estudo preliminar retrospectivo com registros ortodônticos de 28 pacientes (idade média de 8,41±1,45 anos, 13 homens, 15 mulheres) tratados com terapia BioEx usando elevadores de língua por 18,14±9,04 meses (intervalo: 6 a 37 meses). As radiografias cefalométricas laterais pré-tratamento (T0) e pós-tratamento com BioEx (T1) foram analisadas quanto às alterações na postura da língua, por meio de medidas lineares, anteroposteriores e verticais. Os dados foram analisados pelo teste t pareado, considerando-se um nível de significância de 5%. Resultados: O comprimento da língua (CL) e a altura da língua (AL) aumentaram entre T0 e T1, com significância estatística. A diminuição do dorso da língua perpendicular ao plano palatino (valor Td-PP) foi estatisticamente significativa. O aumento da ponta da língua perpendicular à linha vertical pterigomaxilar (PL-PMV) não foi estatisticamente significativo. Conclusões: Esses resultados cefalométricos preliminares indicam que o BioEx pode ser uma modalidade de TMO eficaz no aumento da tonicidade dos músculos da língua, para estabelecer uma postura de língua adequada em repouso.

Effect of Different Head Hole Position on the Rotational Resistance and Stability of Orthodontic Miniscrews: A Three-Dimensional Finite Element Study.

The orthodontic miniscrew is driven into bone in a clockwise direction. Counter-clockwise rotational force applied to the implanted miniscrew can degrade the stability. The purpose of this three-dimensional finite element study was to figure out the effect of shifting the miniscrew head hole position from the long axis. Two miniscrew models were developed, one with the head hole at the long axis and the other with an eccentric hole position. One degree of counter-clockwise rotation was applied to both groups, and the maximum Von-Mises stress and moment was measured under various wire insertion angles from -60° to +60°. All Von-Mises stress and moments increased with an increase in rotational angle or wire insertion angle. The increasing slope of moment in the eccentric hole group was significantly higher than that in the centric hole group. Although the maximum Von-Mises stress was higher in the eccentric hole group, the distribution of stress was not very different from the centric hole group. As the positive wire insertion angles generated a higher moment under a counter-clockwise rotational force, it is recommended to place the head hole considering the implanting direction of the miniscrew. Clinically, multidirectional and higher forces can be applied to the miniscrew with an eccentric head hole position.

Evaluation of strategic uprighting of the mandibular molars using an orthodontic miniplate and a nickel-titanium reverse curve arch wire: Preliminary cephalometric study.

OBJECTIVE: To evaluate the overall treatment effects in terms of the amount of uprighting with changes in the sagittal and vertical positions of mandibular molars after applying an orthodontic miniplate with a nickel-titanium (NiTi) reverse curve arch wire (biocreative reverse curve [BRC] system). METHODS: A total of 30 female patients (mean age, 25.99 ± 8.96 years) were treated with the BRC system (mean BRC time, 10.3 ± 4.07 months). An I-shaped C-tube miniplate (Jin Biomed) was placed at the labial aspect for the alveolar bone of the mandibular incisors. A 0.017 × 0.025-inch NiTi reverse curve arch wire was engaged at the C-tube mini-plate anteriorly and the first and second premolars and molars posteriorly in the mandibular arch. Pre- and post-BRC lateral cephalograms were analyzed. A paired t-test was used to analyze the treatment effects of BRC. RESULTS: The mandibular second molars were intrusively uprighted successfully by the BRC system. Distal uprighting with a controlled vertical dimension was noted on the first molars when they remained engaged in the BRC and the distal ends of the arch wire were laid on the second molars. The mandibular first and second premolars showed a slight extrusion. The changes in the mandibular incisors were unremarkable, while the mandibular molar angulation improved significantly. The lower occlusal plane rotated counterclockwise (MP-LOP: 1.13° ± 2.60°). CONCLUSIONS: The BRC system can provide very effective molar uprighting without compromising the position of the mandibular anterior teeth.

Effect of Different Surface Designs on the Rotational Resistance and Stability of Orthodontic Miniscrews: A Three-Dimensional Finite Element Study.

High orthodontic forces and various directions of applied forces can be associated with loosening of the screw anchorage in the bone. Screw designs have been modified to increase the stability of the miniscrews. This research evaluates the influence of three-designs on the stability of orthodontic miniscrews. A conventionally cylinder-type miniscrew design (Bio-Action screw, Jin-Biomed co., Bucheon, Korea) was set as a control, and three conditions were studied based on modifications of this control design. Condition-1 has narrowed threads in the upper part of the screw; Condition-2 has a notch at the middle part; and Condition-3 has the combination of Condition-1 and Condition-2. The moment required to unwind the miniscrew to five degrees is tested, and the moment generated at the cortical bone and the trabecular bone were calculated with finite element analysis. Compared to the control, all three conditions showed a higher moment required to unwind the miniscrew and a higher moment generated at the cortical bone. At the trabecular bone, condition-2 and -3 showed higher moment than the control, and condition-1 showed similar moment to the control. Condition-3 required a higher overall moment to unwind the miniscrew. These findings validate the design modifications used to increase the rotational resistance.

Finite element analysis of C-expanders with different vertical vectors of anchor screws.

INTRODUCTION: C-expanders are tissue- and bone-borne maxillary expanders that are anchored by 6 orthodontic miniscrews, 3 on each side of the palate. The purpose of the study was to investigate the effect of C-expanders on the circummaxillary sutures and bucco-palatal axis of teeth in 3-dimensional finite element analyses when anchor screw vectors are different. METHODS: Five expansion models were studied on the basis of the vertical positions of anchor screws on the palate. Anchor screws for models A, B, and C were placed symmetrically at 4 mm, 7 mm, and 15 mm below the cementoenamel junction (CEJ), respectively. Anchor screws for models D and E were placed asymmetrically at 4 mm and 15 mm below CEJ and 7 mm and 15 mm below CEJ, respectively. Stress, displacement, and angular changes of the bone and teeth were measured in elastoplastic behavior models using a static-nonlinear simulation in an implicit method. RESULTS: Symmetrical and asymmetrical anchor screw placement with different vertical vectors were compared using finite element analyses on 5 models. CONCLUSIONS: Using different vectors of anchor screws for C-expanders does change the pattern of palatal expansion (null hypothesis was rejected). The current investigation presents a promising future of controlled asymmetric skeletal maxillary expansion when asymmetric maxillary architecture needs to be corrected for successful orthodontic outcomes without involving orthognathic surgeries.

Treatment outcomes of various force applications in growing patients with skeletal Class III malocclusion.

OBJECTIVES: To evaluate skeletal, dentoalveolar, and soft tissue changes between intraoral light force application and extraoral heavy force application in growing patients with skeletal Class III malocclusion. MATERIALS AND: Methods: A retrospective study was conducted with pretreatment and posttreatment lateral cephalometric data from 50 subjects with skeletal Class III malocclusion. In the first group (15 boys, 10 girls; 8.67 ± 2.13 years old), each subject wore a biocreative horseshoe appliance (CHS) with two Class III elastics that exerted a force of 200 g. In the second group (13 boys, 12 girls; 8.96 ± 1.82 years old), each subject wore a Petit-type facemask and a lingual arch with hooks fixed to the maxillary arch with a total force of 700 g. Both groups of patients were instructed to wear the appliance approximately 14 hours a day, and 22 linear measurements and 8 angular measurements were evaluated. Changes of measurements from each group were compared by paired t-tests, considering a 5% significance level. RESULTS: Forward growth of the maxilla, improvement of the maxilla-mandible relationship, and upper incisor flaring were achieved in both groups without any statistically significant difference between them. Lateral cephalometric analysis also showed that U1 exposure, IMPA (Angle between mandibular plane and mandibular incisor axis), FMIA (Angle between FH plan and mandibular incisor axis), and L1-APog (Angle formed by the intersection of tooth axis of lower incisor and A-Pog line, Distance from lower incisor edge to A-Pog line) showed statistically significant differences. Lower incisors were inclined lingually in the CHS group. CONCLUSIONS: During treatment of skeletal Class III malocclusion, the CHS with light Class III intermaxillary elastics therapy exhibits similar orthopedic changes to the maxillary complex and more dental changes to the lower anterior teeth compared with facemask therapy.

Critical issues concerning biocreative strategy in contemporary temporary skeletal anchorage device orthodontics: A narrative review.

Biocreative Orthodontic Strategy (BOS) is designed to establish a physiologically stable occlusion in harmony with masticatory and TMJ function and healthy supporting tissues with strategic use of temporary skeletal anchorage devices (TSADs). This narrative review surveys current research that demonstrates how BOS with TSADs uses a target approach to overcome the limitations experienced with conventional orthodontic treatment. A narrative review article including research on TSADs orthodontics in the permanent dentition. This review is a brief survey of five BOS principles for contemporary TSAD orthodontics: elegant selection of TSADs, bracket prescription to enhance TSAD orthodontics, antero-posterior dimension control, transverse dimension control and airway control issues. Severe malocclusion and craniofacial dysmorphology can be treated with Biocreative Orthodontic Strategy with a minimum number of TSADs. In order to achieve successful treatment outcome using TSADs, it is critical to understand the key diagnosis and treatment principles of BOS and how to develop a target approach for the tooth and bone movement.

Treatment of 2 impacted molars in a large dentigerous cyst (expansile cystic lesion) with combined orthodontic and surgical therapy.

Nonmineralized cysts and cyst-like lesions that frequently occur in the mandible include ameloblastomas, odontogenic keratocysts, and dentigerous cysts. They have specific features of well-demarcated, unilocular, and radiolucent lesions that are often associated with tooth impaction. Although it rarely occurs, these cysts can become extremely large. Furthermore, cyst enlargement causes additional symptoms that can challenge the success of tooth recovery through orthodontic treatment. This clinical report presents the successful eruption of 2 impacted molars in a large dentigerous cyst treated with marsupialization and orthodontic traction using an orthodontic miniplate anchorage over a 4-year treatment period.

Finite element study of controlling factors of anterior intrusion and torque during Temporary Skeletal Anchorage Device (TSAD) dependent en masse retraction without posterior appliances: Biocreative hybrid retractor (CH-retractor).

OBJECTIVES: To evaluate, using the finite element method (FEM), the factors that allow control of the anterior teeth during en masse retraction with the Biocreative hybrid retractor (CH-retractor) using different sizes of nickel-titanium (NiTi) archwires and various gable bends on the stainless-steel (SS) archwires. MATERIALS AND METHODS: Using FEM, the anterior archwire section, engaged on the anterior dentition, was modeled in NiTi, and another assembly, the posterior guiding archwire, was modeled in SS. Two dimensions (0.016 × 0.022- and 0.017 × 0.025-inch NiTi) of the anterior archwires and different degrees (0°, 15°, 30°, 45°, and 60°) of the gable bends on the guiding wire were applied to the CH-retractor on the anterior segment to evaluate torque and intrusion with 100-g retraction force to TSADs. Finite element analysis permitted sophisticated analysis of anterior tooth displacement. RESULTS: With a 0° gable bend all anterior teeth experienced extrusion. The canines showed a larger amount of extrusion than did the central and lateral incisors. With a gable bend of >15°, all anterior teeth exhibited intrusion. Bodily movement of the central incisor required a 30°âˆ¼45° gable bend when using anterior segments of 0.016 × 0.022-inch NiTi and 15°âˆ¼30° gable bend with the 0.017 × 0.025-inch NiTi. CONCLUSIONS: With the CH-retractor, varying the size of the NiTi archwire and/or varying the amount of gable bend on the SS archwire affects control of the anterior teeth during en masse retraction without a posterior appliance.

Molar inclination and surrounding alveolar bone change relative to the design of bone-borne maxillary expanders: A CBCT study.

OBJECTIVE: To evaluate the molar inclination and skeletal and alveolar bone changes when comparing tooth bone-borne (MSE) and tissue bone-borne type maxillary expanders (C-expander) using cone-beam computed tomography (CBCT) in late adolescence. MATERIALS AND METHODS: A sample of 48 late-adolescent patients were divided into two groups according to the type of expander: MSE group (n = 24, age = 19.2 ± 5.9 years) and C-expander group (n = 24, age = 18.1 ± 4.5 years). CBCT scans were taken before treatment and 3 months after expansion. Transverse skeletal and dental expansion, alveolar inclination, tooth axis, buccal alveolar bone height, thickness, dehiscence, and fenestration were evaluated on the maxillary first molar. Paired t-test, independent t-test, Pearson's chi-square test, and Spearman correlation analysis were performed. RESULTS: The MSE group produced greater dental expansion (P < .05), whereas skeletal expansion was similar in both groups (P = .859). The C expander group had more alveolar bone inclination change (P < .01), and the MSE group had more buccal tipping of the anchorage teeth (P < .01 or .001). Buccal alveolar bone height loss and thickness changes were greater in the MSE group (P < .01 or <.001). Formation of dehiscences was more frequent in the MSE group (P < .001), whereas for fenestrations, there were no significant differences between the two groups. Buccal bone height loss in the MSE group had a negative correlation with initial buccal bone thickness. CONCLUSIONS: The incorporation of teeth into bone-borne expanders resulted in an increase in the severity of side effects. For patients in late adolescence, tissue bone-borne expanders offer comparable skeletal effects to tooth bone-borne expanders, with fewer dentoalveolar side effects.

Autotransplantation of premolars and space closure in a patient with inflamed sinuses.

Congenital absence of permanent teeth can be treated by means of dental implants and prosthetics. Tooth autotransplantation is an alternative in growing patients because continued eruption of the transplanted tooth and associated alveolar bone growth can be expected. This clinical report presents tooth autotransplantation in a 10-year-old boy with chronic maxillary rhinosinusitis, diagnosed by the department of otorhinolaryngology. The patient's mandibular second premolars were transplanted to a congenitally edentulous maxillary premolar region. There was insufficient alveolar bone during transplantation because of pneumatization, but normal root development with vertical alveolar bone growth was observed during a 3-year follow-up. Healing of the transplant in the right side without closing of the apex and without signs of obliteration after 4 years is exceptional.