Craniomandibular transverse tomographic evaluation after anterior open bite orthodontic treatment with miniplates anchorage.

BACKGROUND: Skeletal anterior open bite (SAOB) represents one of the most complex and challenging malocclusions in orthodontics. Orthodontic treatment supported by miniplates enable to reduce the need for orthognathic surgery. Transverse dimension may be affected by intrusion biomechanics. This study aims to assess transverse bone alterations in patients with SAOB who underwent orthodontic treatment with absolute anchorage using four miniplates. METHODS: A total of 32 patients of both sexes, with an average age of 33.8 years, diagnosed with SAOB and treated orthodontically with four miniplates (one in each hemiarch), were selected for this study. Tomographic examinations were performed before (T1) and after (T2) orthodontic treatment. Linear measurements (width of the maxillary base, maxillary alveolar, maxillary root, maxillary dental cusp, mandibular alveolar) and angular measurements (maxillary intermolar angle) were assessed in these images. The Shapiro-Wilks normality tests were applied to verify data distribution, and the paired t-test was used to compare the initial and final measures obtained. RESULTS: Among the evaluated parameters, the maxillary alveolar width, maxillary dental cusp width, mandibular alveolar cusp width, and intermolar angle showed statistically significant differences between T1 and T2 (p < 0.05). However, maxillary base and maxillary root widths showed no significant difference (p > 0.05). CONCLUSIONS: Intrusion and distalization with miniplates in SAOB therapy may lead to significant expansive changes, due to molars cusps width and buccal inclination increase restricted at the alveolar level.

Combined orthodontic-orthognathic management of a patient with generalized short root anomaly and anterior open bite.

Short root anomaly is a rare dental disorder affecting tooth root development. It is characterized by reduced root-to-crown ratios (1:1 or less) and rounded apices. The short roots introduce a potential complication during orthodontic treatment. This case report describes managing a girl with generalized short root anomaly, an open bite, impacted maxillary canines, and a bilateral crossbite. In the first phase of treatment, the maxillary canines were extracted, and the transverse discrepancy was corrected with a bone-borne transpalatal distractor. In the second phase of treatment, a mandibular lateral incisor was removed, fixed appliances were placed in the mandibular arch, and bimaxillary orthognathic surgery was performed. A satisfactory result was obtained without further root shortening, adequate smile esthetics, and 2.5-year posttreatment stability.

Long term stability of a high-angle skeletal Class II open bite treated with high-pull headgear and modified transpalatal arch: A case report.

This case report describes the treatment of an adolescent patient with an Angle Class II malocclusion, severe open bite and overjet, proclined incisors, skeletal Class II anteroposterior dysplasia, high mandibular plane angle and convex profile. The importance of stopping of a prolonged thumb sucking habit, which was a major causative factor of the open bite is discussed. A combination of a high-pull headgear and a modified transpalatal arch with a loop embedded with resin, at a distance from the palate, were used along with an Edgewise appliance. Treatment timing, favourable growth and good patient response led to an optimal outcome with excellent stability of the treatment results five years and five months post-treatment.

Comparison of regional soft tissue changes after bimaxillary rotational surgery between class III deformity with overbite and open bite: A 3D imaging analysis.

BACKGROUND: This prospective study aimed to compare regional soft tissue changes between patients with class III overbite and open bite deformities treated with bimaxillary surgery involving clockwise and counter-clockwise mandibular setback, respectively. MATERIAL AND METHODS: Class III deformity adults receiving Le Fort I and bilateral sagittal split osteotomies were grouped according to the incisal occlusion: overbite (n = 30) and open bite (n = 30). Combined cone-beam CT scans and 3D facial photographs preoperative and at least 1-year postoperative were taken to assess the soft tissue changes. RESULTS: Postoperative changes for the overbite and open bite groups included anterior repositioning of nose (-0.8 ± 1.2 mm and -1.1 ± 1.1 mm, respectively) and cheek (-1.9 ± 1.3 mm and -1.7 ± 2.6 mm, respectively), posterior repositioning of chin (5.2 ± 4.0 mm and 4.9 ± 3.2 mm, respectively), and medial (-1.7 ± 2.0 mm and -1.9 ± 2.1 mm, respectively) and posterior (2.7 ± 1.4 mm and 2.8 ± 2.3 mm, respectively) repositioning of bilateral angles. Posterior (1.2 ± 2.0 mm and 5.1 ± 3.3 mm) and inferior (-1.4 ± 2.2 mm and -2.4 ± 2.7 mm) repositioning of upper lip and lower lip occurred in overbite group. Inferior (-2.3 ± 2.4 mm) and superior (3.7 ± 3.4 mm) repositioning of chin occurred in the overbite and open bite groups, respectively. CONCLUSIONS: Treatment of class III overbite and open bite deformities with bimaxillary rotational surgery resulted in comparable regional soft tissue changes, except for upper lip, lower lip and chin.

Mandibular angle morphology in open bite subjects according to the skeletal relationship: a cbct short report / Morfología del ángulo mandibular en sujetos con mordida abierta de acuerdo a la relación esquelética: un informe breve en cbct

Aim: The purpose of this research was to three-dimensionally evaluate the mandibular angle morphology in open bite subjects with different sagittal skeletal relationships. Material and Methods: Cone beam computed tomography (CBCT) images of 26 subjects (12 men and 14 women) with anterior open bite were evaluated. The sample included 3 groups categorized by their sagittal skeletal relationship (based on ANB angle and anteroposterior dysplasia indicator (APDI)): Class I (n=9), Class II (n=6) and Class III (n=11). The total gonial angle, upper gonial angle, lower gonial angle, intergonial width, interantegonial width and antegonial notch depth were measured. ANOVA and Tukey tests were used for intergroup comparison. The Kruskal Wallis test was also used when necessary. In addition, the Pearson correlation coefficient was calculated to evaluate significant correlations between overbite and antegonial notch depth with gonial angle, Frankfurt mandibular plane angle (FMA) and the palatal plane-mandibular plane (PP-MP). Results: A significant difference was only found on the upper gonial angle between Class II and Class III (p=0.047). The upper gonial angle showed greater values (48°±3°) with the mandibular branch toward backward in Class III subjects and lower values (42.42°±4.39°) with the mandibular ramus leaning forward in subjects with Class II skeletal relationship. Besides, only a statistically significant correlation was found between overbite and the lower gonial angle (r=-0.418, p=0.034). Conclusion: Mandibular angle morphology is similar in anterior open bite subjects with different sagittal skeletal relationships, except for the upper gonial angle which is increased in Class III and decreased in Class II subjects with open bite. Lower gonial angle is negatively correlated with overbite. This difference should be considered by orthodontists when planning their treatments.

Objetivo: El propósito de esta investigación fue evaluar tridimensionalmente la morfología del ángulo mandibular en sujetos de mordida abierta con diferentes relaciones esqueléticas sagitales. Material y Métodos: Se evaluaron imágenes de tomografía computarizada de haz cónico (CBCT) de 26 sujetos (12 hombres y 14 mujeres) con mordida abierta anterior. La muestra incluyó 3 grupos categorizados por su relación esquelética sagital (según el ángulo ANB y el indicador de displasia anteroposterior (APDI)): Clase I (n=9), Clase II (n=6) y Clase III (n=11). Se midieron el ángulo goniaco total, el ángulo goniaco superior, el ángulo goniaco inferior, el ancho intergonial, el ancho interantegonial y la profundidad de la entalladura antegonial. Se utilizaron las pruebas ANOVA y Tukey para la comparación intergrupal. La prueba de Kruskal Wallis también se utilizó cuando fue necesario. Además, se calculó el coeficiente de correlación de Pearson para evaluar correlaciones significativas entre la sobremordida y la profundidad de la entalladura antegonial con el ángulo goniaco, el ángulo del plano mandibular de Frankfurt (FMA) y el plano palatino-plano mandibular (PP-MP). Resultados: Solo se encontró una diferencia significativa en el ángulo goniaco superior entre la Clase II y la Clase III (p=0.047). El ángulo gonial superior mostró valores mayores (48°±3°) con la rama mandibular hacia atrás en sujetos Clase III y valores más bajos (42,42°±4,39°) con la rama mandibular inclinada hacia adelante en sujetos con Clase II esquelética relación. Además, solo se encontró una correlación estadísticamente significativa entre la sobremordida y el ángulo goniaco inferior (r= -0,418, p= 0,034). Conclusión: La morfología del ángulo mandibular es similar en sujetos con mordida abierta anterior con diferentes relaciones esqueléticas sagitales, excepto por el ángulo goniaco superior que aumenta en la Clase III y disminuye en sujetos de Clase II con mordida abierta. El ángulo gonial inferior se correlaciona negativamente con la sobremordida. Los ortodoncistas deben considerar esta diferencia al planificar sus tratamientos.

Computer-aided surgical workflow in a surgery - First orthognathic approach to correct anterior open bite in a young adult with temporomandibular disorders.

An 18-year-old female patient with temporomandibular disorders (TMD) history sought medical care in orthodontic-orthognathic interdisciplinary department with chief complaint of anterior open bite. After splint therapy to seat the condylar into the musculo-skeletally stable position, a surgery-first approach was formulated assisted by 3D virtual planning and transferred to the surgery by computer-aided manufacturing splint. No TMD symptom reoccurrence was reported or noted. Stable occlusion and satisfactory facial aesthetics were achieved. In the 18-month follow-up, no clinically significant open bite relapse occurred. This case report describes the remarkable role that computer-assisted surgical simulation could play throughout the surgical-orthodontic procedure to correct the skeletal open bite deformity.

Condylar degeneration in anterior open bite patients: A cone beam computed tomography study.

OBJECTIVES: The purpose of this study was to investigate the prevalence of condylar degeneration in patients with anterior open bites (AOB). STUDY DESIGN: Cone beam computed tomography (CBCT) scans of 194 patients with AOB (108 with skeletal open bites and 86 with dental open bites) and 100 patients serving as controls were included in this retrospective study. Two oral and maxillofacial radiologists categorized each of the 588 condyles as normal, degenerative-active, or degenerative-repair. The χ2 analysis with Bonferroni adjustment was used to evaluate the relationship of condylar status (normal vs degenerative) to anterior open bites. RESULTS: Of the 103 degenerative condyles, there were 59 in the group with skeletal open bites, 14 in the group with dental open bites, and 30 in the control group. Condylar degeneration occurred twice as frequently in patients with skeletal open bites as it did in the control group (P < .0001). Conversely, a greater frequency of normal condyles was found in the group of patients with dental open bites (P = .0002). The group with skeletal open bites also showed a significantly higher frequency of bilateral degenerative condyles (P = .0001). The frequency of condylar degeneration did not differ significantly between female and male individuals. CONCLUSIONS: Degenerative condylar change was significantly more likely in patients with skeletal open bites and less likely in patients with dental open bites.

Intermaxillary elastics on skeletal anchorage and MARPE to treat a class III maxillary retrognathic open bite adolescent: A case report.

Class III malocclusion when accompanied with transverse and vertical maxillomandibular discrepancies such as posterior crossbite and vertical open bite leads to complicated orthodontic treatment. Proper diagnosis and treatment planning are important in such patients for a successful orthodontic outcome. A common treatment approach for patients with class III malocclusion is to wait for the completion of growth and plan orthognathic surgery in conjunction with orthodontic treatment. However, performing no treatment and waiting for growth to be completed during teen years could lead to negative effects on the patient's self-esteem. In such cases, a non-surgical option with skeletal anchorage could be used to correct the malocclusion without surgical intervention. This case report shows that in patients with severe class III malocclusion, skeletal anchorage can be used for the correction of anterior crossbite with intermaxillary elastics.

Lingual treatment of an adult patient with an iatrogenic class II anterior open bite: Report of a case with a non-surgical orthodontic approach.

INTRODUCTION: The treatment of adult patients presenting an open bite is a real challenge for orthodontists due to the complexity of the malocclusion. The diagnosis is essential to identify aetiological factors and establish the best aesthetic and functional therapeutic prognosis. Among the aetiological factors, iatrogenic treatment history has to be considered. It is the case here where a regrettable unsuitable splint for bruxism treatment forced an open bite to appear. MATERIAL AND METHOD: This case report presents an adult women with a large open bite due to an occlusal splint not covering the last mandibular molars. It was not really a vertical skeletal excess but more a mandibular clockwise rotation linked to the molar extrusions, which created a dento-alveolar open bite and labio-mental contractions during lip closure. Treatment objectives were the intrusion of the third and second molars, the extrusion of incisors to obtain a counter clockwise mandibular rotation. The patient was treated with an aesthetic and customized lingual appliance with no orthognathic surgery. A physiotherapy was followed by the patient when the open bite was closed in order to facilitate and stabilize the intercuspation. RESULTS: A complete closing of the open bite was reached after two years of treatment. The superimposition showed the anticlockwise mandibular rotation. The levelling with posterior intrusion and the incisors extrusion reduced the vertical dimension with success. After 3years of retention, the occlusal stability was obtained. CONCLUSION: The intrusion of the molars associated with a counter clockwise mandibular rotation made it possible the incisor extrusion. The occlusal balance with physiotherapy and patient compliance maintained the closure. In this way, the iatrogenic effects of the poorly designed bite splint were repaired.

Treatment of adult patient with hyperdivergent retrognathic phenotype and anterior open bite: report of a case with non-surgical orthodontic approach.

Adult patients with anterior open bite and hyperdivergent retrognathic phenotype demand complex treatments, as premolar extractions, molar intrusion or orthognathic surgery. In the present clinical case, a young adult patient without significant growth, with Class I and anterior open bite, was treated with four premolar extractions. The therapeutic result shows good intercuspation, good facial esthetic, good function balance, and stability in a two-year post-fixed treatment follow-up.

Incisor root length in individuals with and without anterior open bite: a comparative CBCT study

ABSTRACT Objective: This study aimed to compare the root length of maxillary and mandibular incisors between individuals with open bite versus matched individuals with adequate overbite. Methods: This comparative, matched and retrospective study included 48 cone beam computed tomographies (CBCTs) obtained at a university radiological center. Scans belonged to 24 individuals with open bite (overbite ≤ 0 mm) and 24 individuals with adequate overbite (controls). Both groups were matched by age, sex, malocclusion classification and skeletal characteristics (ANB and FMA angles). Root length of each maxillary and mandibular incisor was measured in millimeters (mm) in a sagittal section from a perpendicular line to the enamel cement junction until the root apex (384 length measurements were made). The means of root length in both groups were compared using t-tests. In addition, correlations between variables were evaluated with the Pearson correlation coefficient (α = 0.05). Results: In both groups, the root length of the upper central incisors was approximately 12 mm and the root length of the maxillary lateral incisors was approximately 13 mm (p˃ 0.05). Likewise, the root length of lower central incisors in both groups measured approximately 12 mm (p˃ 0.05). However, the mandibular lateral incisor roots of open bite patients were significantly longer than in the normal overbite patients (approximately 1 mm, p= 0.012 right side, p= 0.001 left side). Conclusions: Root length of maxillary incisors and central mandibular incisor is similar in individuals with or without open bite, but the mandibular lateral incisor roots in open bite patients were significantly longer than in the normal overbite patients.

RESUMO Objetivo: O presente estudo teve como objetivo comparar o comprimento radicular de incisivos superiores e inferiores em indivíduos com mordida aberta versus indivíduos com sobremordida normal. Método: Esse estudo comparativo e retrospectivo incluiu 48 tomografias computadorizadas de feixe cônico (TCFC) obtidas em um centro radiológico universitário. As tomografias foram realizadas em 24 indivíduos com mordida aberta (sobremordida ≤ 0 mm) e 24 indivíduos com sobremordida normal (controle). Ambos os grupos foram compatibilizados de acordo com a idade, sexo, má oclusão e padrão esquelético (ângulos ANB e FMA). O comprimento radicular de todos os incisivos superiores e inferiores foi medido em milímetros (mm) em um corte sagital, de uma linha perpendicular à junção cemento-esmalte até o ápice radicular (384 medidas de comprimento foram realizadas). A média de comprimento radicular em ambos os grupos foi comparada utilizando-se o teste t. Adicionalmente, correlações entre as variáveis foram avaliadas usando o coeficiente de correlação de Pearson (α = 0,05). Resultados: Em ambos os grupos, o comprimento radicular dos incisivos centrais superiores foi de, aproximadamente, 12 mm, e o comprimento radicular dos incisivos laterais superiores foi de, aproximadamente, 13 mm (p˃ 0,05). Da mesma forma, o comprimento radicular dos incisivos centrais inferiores, em ambos os grupos, obteve a medida de aproximadamente 12 mm (p>0,05). No entanto, o comprimento radicular dos incisivos laterais inferiores em indivíduos com mordida aberta foi significativamente maior em comparação aos pacientes com sobremordida normal (aproximadamente 1 mm, p=0,012 do lado direito, p=0,001 do lado esquerdo). Conclusões: O comprimento radicular de incisivos superiores e incisivos centrais inferiores foi similar em indivíduos com ou sem mordida aberta, mas o comprimento radicular de incisivos laterais inferiores em indivíduos com mordida aberta foi significativamente maior em comparação a pacientes com sobremordida normal.

Negligible tooth resorptions after anterior open bite treatment using skeletal anchorage with miniplates

ABSTRACT Introduction: When miniplates are used as anchoring for orthodontic mechanics for anterior open bite correction by retraction of anterior teeth and posterior teeth intrusion and retraction, orthodontically induced inflammatory external apical root resorption is clinically negligible. Methods: A homogeneous sample of 32 patients was used, and the roots of the teeth were compared on CT scans performed before and after orthodontic treatment. Results: The observed root resorption was minimal, and this can be explained by the uniform distribution of forces in several teeth, simultaneously, in the set of the dental arch and in the bone that supports the teeth. Conclusion: The most important thing to prevent root resorption in orthodontic practice, besides being concerned with the intensity of the applied forces, is to be careful with its distribution along the roots of each tooth, in the dental arch and in the bone that supports the teeth.

RESUMO Introdução: Quando são utilizadas miniplacas como ancoragem para a mecânica ortodôntica de correção da mordida aberta anterior por meio da retração dos dentes anteriores e intrusão e retração dos dentes posteriores, as reabsorções radiculares apicais externas inflamatórias induzidas ortodonticamente são clinicamente irrelevantes. Métodos: Usou-se uma amostra homogênea de 32 pacientes, e comparou-se as raízes dos dentes em tomografias realizadas antes e depois do tratamento ortodôntico. Resultados: As reabsorções radiculares observadas foram mínimas, e isso pode ser explicado pela distribuição uniforme das forças em vários dentes, simultaneamente, no conjunto da arcada dentária e no osso que suporta os dentes. Conclusão: O mais importante para se prevenir as reabsorções radiculares na prática ortodôntica, além de se preocupar com a intensidade das forças aplicadas, é tomar cuidado com a sua distribuição ao longo das raízes de cada dente, na arcada dentária e no osso que suporta os dentes.

Relations between anterior disc displacement and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle.

In this study we investigated the relation between anterior disc displacement (ADD) and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle. Thirty female patients (60 joints) with both conditions were evaluated. Magnetic resonance imaging of the temporomandibular joint (TMJ) was used to diagnose both ADD and changes to the mandibular condyle (erosion, osteophyte, and deformity). The relations among ADD, changes to the mandibular condyle, and maxillomandibular morphology were examined statistically. Changes to the mandibular condyle had a higher score than sym anterior open bite, the deviated side in asymmetric anterior open bite, and the non-deviated side. The score for disc displacement on the non-deviated side was lower than both the sym side and the deviated side. Unilateral changes to the mandibular condyle and unilateral disc displacement were not apparent in sym anterior open bite, but a unilateral non-displaced disc was seen only on the asymmetric side. Mandibular condylar changes were significantly more common on the deviated, than on the non-deviated, side. The SNB angle was significantly smaller, and the ANB, GZN, and SN-mandibular plane angles were significantly larger in sym anterior open bite. Overjet, ANB angle, GZN angle, and SN-MP angle were significantly larger, and the SNB angle was significantly smaller, in the presence of ADD without reduction and mandibular condylar deformity. We conclude that the prevalence of ADD without reduction and changes to the mandibular condyle were related to mandibular asymmetry and mandibular morphology in anterior open bite. This retrospective study suggests that ADD without reduction and mandibular condylar bone changes may be related to the progression of skeletal class II open bite and mandibular asymmetry in cases of skeletal open bite.

Orthognathic surgery with two-segment le fort i and sagittal split ramus osteotomies of open bite deformity in an amelogenesis imperfecta patient via virtual planning: A case report.

Amelogenesis imperfecta (AI) is an enamel defect and is often associated with the anterior open bite (AOB) and transverse maxillary deficiency. It is known that in such cases when AI and AOB appeared together, posterior maxillary impaction with or without bilateral mandibular ramus osteotomies is a frequently preferred treatment option. Virtual planning is more reliable rather than the conventional model surgery planning, especially for complicated cases. Usage area of virtual 3D anatomical models reconstructed from Cone Beam Computed Tomography (CBCT) data is expanding day by day for both diagnosis and surgical planning. The aim of this study is to present a patient with AI and AOB and transverse maxillary deficiency and management of this case with virtually planned two-segment Le fort I and sagittal split ramus osteotomies followed by prosthetic rehabilitation.

The National Dental Practice-Based Research Network Adult Anterior Open Bite Study: Treatment recommendations and their association with patient and practitioner characteristics.

INTRODUCTION: This aim of this paper is to describe and identify the practitioner and patient characteristics that are associated with treatment recommendations for adult anterior open bite patients across the United States. METHODS: Practitioners and patients were recruited within the framework of the National Dental Practice-Based Research Network. Practitioners were asked about their demographic characteristics and their treatment recommendations for these patients. The practitioners also reported on their patients' dentofacial characteristics and provided initial cephalometric scans and intraoral photographs. Patients were asked about their demographic characteristics, previous orthodontic treatment, and goals for treatment. Four main treatment groups were evaluated: aligners, fixed appliances, temporary anchorage devices (TADs), and orthognathic surgery. Extractions were also investigated. Predictive multivariable models were created comparing various categories of treatment as well as extraction/nonextraction decisions. RESULTS: Ninety-one practitioners (mostly orthodontists) and 347 patients were recruited from October 2015 to December 2016. Increased aligner recommendations were associated with white and Asian patients, the presence of tongue habits, and female practitioners. TADs were recommended more often in academic settings. Recommendations for orthognathic surgery were associated with demographic factors, such as availability of insurance coverage and practitioner race/ethnicity, and dentofacial characteristics, such as anteroposterior discrepancies, more severe open bites, and steeper mandibular plane angles. Extraction recommendations were largely associated with severe crowding and incisor proclination. CONCLUSIONS: Both doctor and patient demographic factors, as well as dentofacial characteristics, were significantly associated with treatment recommendations for adult anterior open bite patients.

Comprehensive treatment approach for bilateral idiopathic condylar resorption and anterior open bite with customized lingual braces and total joint prostheses.

This case report describes the successful treatment of a 14-year-old girl with severe bilateral idiopathic condylar resorption and resultant mandibular retrusion, increased overjet, and anterior open bite. The nonextraction treatment plan included (1) aligning and leveling the teeth in both arches, (2) performing Le Fort I maxillary osteotomy, bilateral condylectomy, and mandibular joint replacement, and (3) postsurgical correction of the malocclusion. The orthodontic treatment was initiated with the use of custom lingual appliances followed by orthognathic surgery planned with virtual surgical planning. Patient-fitted and customized temporomandibular joint implants were designed and manufactured based on the patient's stereolithic bone anatomic model. Treatment was concluded with detailed orthodontic finishing. Optimum esthetic and functional results were achieved with the cooperation of 2 specialties and the use of state-of-the-art technology.

A comprehensive treatment approach for idiopathic condylar resorption and anterior open bite with 3D virtual surgical planning and self-ligated customized lingual appliance.

INTRODUCTION: We report the successful treatment of a 38-year-old woman with bilateral idiopathic condylar resorption and anterior open bite. She had incompetent lips, a gummy smile, increased lower facial height, high mandibular plane angle, skeletal and dental Class II malocclusion with mild mandibular crowding, increased overjet, and mandibular midline deviation to the right. METHODS: The treatment plan included: (1) presurgical alignment and leveling of the teeth in both arches; (2) jaw motion tracking (JMT) to detect mandibular movement; (3) 3-piece maxillary osteotomies with mandibular reconstruction and bilateral coronoidectomies; and (4) postsurgical correction of the malocclusion. The orthodontic treatment was performed with the use of custom lingual braces and clear brackets and the orthognathic surgery was planned with the use of virtual surgical planning. RESULTS: The idiopathic condylar resorption and anterior open bite were treated, crowding was eliminated in the lower anterior segment, correction of skeletal and dental Class II malocclusion was obtained, mandibular plane angle was reduced, and facial profile improved. CONCLUSIONS: The results suggest that esthetic and functional results can be achieved with the cooperation of 2 specialties and with the use of state-of-the-art technology.

Three-dimensional assessment of external apical root resorption after maxillary posterior teeth intrusion with miniscrews in anterior open bite patients

ABSTRACT Objective: The objective of this study was to assess the external apical root resorption (EARR) of the maxillary posterior teeth after intrusion with miniscrews. Methods: Fifteen patients (13 females and 2 males) with age ranging from 14.5 to 22 years (mean 18.1 ±2.03 years) were selected to participate in this study. All patients presented with anterior open bite of 3 mm or more. An intrusion force of 300 g was applied on each side to intrude the maxillary posterior teeth. Cone beam computed tomography (CBCT) scans were taken pretreatment and post-intrusion and were analyzed to evaluate the EARR. Results: The maxillary posterior teeth were intruded in average 2.79 ± 0.46 mm (p< 0.001) in 5.1 ± 1.3 months, and all examined roots showed statistically significant EARR (p< 0.05) with an average of 0.55 mm, except the distobuccal root of the left first permanent molars and both the palatal and buccal roots of left first premolars, which showed no statistically significant changes. Conclusions: The evaluated teeth presented statistically significant EARR, but clinically, due to the small magnitude, it was not considered significant. Moreover, the CBCT provided a good visualization of all roots in all three planes, and it was effective in detecting minimal degrees of EARR.

RESUMO Objetivo: o objetivo desse estudo foi verificar a existência de reabsorção radicular apical externa (RRAE) em dentes posterossuperiores após intrusão ancorada em mini-implantes. Métodos: quinze pacientes (13 mulheres e 2 homens) com a idade variando entre 14,5 e 22 anos (média de 18,1 ± 2,03 anos) foram selecionados para participar desse estudo. Todos os pacientes possuíam mordida aberta anterior de 3mm ou mais. Uma força de 300 gramas foi aplicada em cada lado para intruir os dentes posterossuperiores. Tomografias computadorizadas de feixe cônico (TCFC), adquiridas antes do tratamento e após a intrusão, foram comparadas para se avaliar a RRAE. Resultados: os dentes posterossuperiores foram intruídos em média 2,70 ± 0,46 mm (p< 0,001) em 5,1 ± 1,3 meses, e todas as raízes examinadas mostraram RRAE estatisticamente significativa (p< 0,05), com média de 0,55 mm, exceto pela raiz distovestibular dos primeiros molares permanentes esquerdos, e pelas raízes palatina e vestibular dos primeiros pré-molares esquerdos, que não apresentaram mudanças estatisticamente significativas. Conclusões: os dentes avaliados apresentaram RRAE estatisticamente significativa, a qual, porém, não foi considerada clinicamente significativa, devido à sua reduzida magnitude. Além disso, a TCFC possibilitou uma boa visualização de todas as raízes nos três planos espaciais, e foi eficaz para detecção de níveis mínimos de RRAE.

Accuracy of soft tissue prediction in surgery-first treatment concept in orthognathic surgery: A prospective study.

PURPOSE: The purpose of this study was to provide a quantitative accuracy assessment of soft tissue predictions generated by a computer-aided maxillofacial planning system in patients undergoing orthognathic surgery following the "surgery-first" treatment. MATERIALS AND METHODS: For this study, we looked at 16 patients with open bite dentofacial-dysmorphosis who underwent orthognathic surgery. Surgeries were planned using conventional sketches and the newly developed computer-assisted SOTIRIOS planning software (developed by the authors). Validation procedures were performed in the following steps: (1) Standardized registration of the pre- and postoperative CT volumes; (2) Automated adjustment of the bone-related preoperative planning to the actual postoperative bony displacement; (3) Simulation of soft tissue changes according to the definitive bony movements; and (4) Calculation of soft tissue differences between the predicted and the actual 6-month postoperative results by distance mapping. RESULTS: The program produced a clinically satisfactory 3D soft tissue prediction, with a mean error of 1.46 mm ± 1.53 mm. The program was suitable for use in virtual surgical planning without technical assistance. CONCLUSION: This study shows that the program is quite accurate, enabling the surgeon to predict the outcome of the soft tissue. This has the potential to promote the routine application of the surgery-first approach in patients suffering from open bite.