Vertical Mouth Opening Requirements for CAD/CAM Fully Guided Implant Surgery: An Analysis of Different Implant Systems.

PURPOSE: To determine the vertical space required for implant osteotomy preparation when utilizing a CAD/CAM fully guided surgical template. MATERIALS AND METHODS: A total of 14 surgical osteotomy drills (individual and sequential drills) were collected and measured individually using a digital caliper, as well as the total length when the drills were positioned in a surgical handpiece. The height of the surgical guide sleeves and the offset of 14 implant systems in the market were also collected. RESULTS: The vertical dimension of the drills included in this study ranged from 28.2 to 46.3 mm. When these drills were inserted into the handpiece, the total length ranged from 30.0 to 49.5 mm. The height of the surgical guide sleeve and the offset required for the guide had a range of 3.2 to 7.0 mm and 5.0 to 13.5 mm, respectively. This dimension resulted in the total vertical space required for CAD/CAM fully guided surgical templates for each implant system, which ranged from 30.0 to 58.5 mm. CONCLUSIONS: Limited mouth opening can pose challenges and limitations in both guided and nonguided dental implant surgery. It can affect the accessibility of surgical implant placement and may result in increased patient discomfort, surgical implant positioning errors, and postoperative complications. Clinicians should determine the patient's mouth opening capabilities during the treatment planning phase prior to deciding on the appropriate implant system to be used and the implant placement technique.

Reabilitação estética e funcional inferior com aumento de dimensão vertical de oclusão: relato de caso / Lower aesthetic and functional rehabilitation with increased vertical dimension of occlusion: case report

Os hábitos parafuncionais são caracterizados como movimentos involuntários e multifatoriais, podendo ter como principais fatores causais o estresse e a ansiedade. Essa condição acarreta, muitas vezes, na diminuição da dimensão vertical de oclusão por conta do desgaste dentário, prejudicando mastigação, fonação, estética e funções, sendo, portanto, de suma importância seu diagnóstico e tratamento. Aquele se dá através da anamnese, associado ao exame clínico e, se necessário, exames complementares. A abordagem clínico-terapêutica é ampla e multidisciplinar, devendo atuar no fator causal e suas consequências, existindo uma gama de possibilidades terapêuticas, tornando, por isso, um tratamento complexo. Por tal, o presente estudo aborda uma opção de tratamento em um relato de um caso clínico onde o paciente apresentava perda de dimensão vertical de oclusão, desgastes dentários e queixas funcionais e estéticas. A técnica se deu por meio do aumento da dimensão vertical através de Table Tops e facetas anteriores, ambas em resina composta atrelado ao aconselhamento multidisciplinar. Este trabalho mostrou a importância da realização de uma técnica reabilitadora correta, pois a sobrecarga e a perda de dimensão vertical podem gerar danos ao sistema estomatognático, prejudicando a articulação temporomandibular, ligamentos, músculos e dentes. Nesse contexto, conclui-se que é de suma importância uma avaliação minuciosa do paciente, tendo um planejamento correto do caso para um correto tratamento e um prognóstico positivo(AU)

Parafunctional habits are characterized as involuntary and multifactorial movements, and the main causal factors may be stress and anxiety. This condition often leads to a decrease in the vertical dimension of occlusion due to tooth wear, impairing chewing, phonation, aesthetics and functions, and therefore its diagnosis and treatment are of supreme importance. The former takes place through anamnesis, associated with a clinical examination and, if necessary, additional tests. The clinicaltherapeutic approach is wide and multidisciplinary and must operate on the causal factor and its consequences, with a range of therapeutic possibilities, turning it a complex treatment. Therefore, the study presents a treatment of a case report where the patient had loss of vertical dimension of occlusion, dental wear and functional and aesthetic complaints. The technique was performed by increasing the vertical dimension through Table Tops and anterior veneers, both in composite resin attached to a multidisciplinary advice. This work showed the importance of performing a correct rehabilitation technique, because the overload and loss of vertical dimension can cause damage to the stomatognathic system, harming the temporomandibular joint, ligaments, muscles and teeth. In this context, it is concluded that a thorough evaluation of the patient is very important, having a correct planning of the case for a correct treatment and a positive prognosis(AU)

Reabilitação oral com próteses parciais removíveis após restabelecimento de dimensão vertical de oclusão e tratamento multidisciplinar: relato de caso / Oral rehabilitation with removable partial dentures after restoration of the vertical dimension of occlusion and multidisciplinary treatment: case report

As próteses parciais removíveis (PPRs) são uma alternativa de tratamento viável na prática clínica para reabilitar arcos parcialmente desdentados. Entretanto, o planejamento dessas próteses e preparo bucal prévio são frequentemente negligenciados. O presente artigo tem como objetivo relatar o caso clínico de uma reabilitação oral com PPRs superior e inferior após abordagem multidisciplinar, de modo a enfatizar as fases de um planejamento criterioso e de preparo prévio dos dentes pilares, visando o sucesso e a longevidade da reabilitação. Paciente do sexo masculino de 57 anos de idade compareceu à clínica da Faculdade de Odontologia de Bauru, Universidade de São Paulo, queixando-se da estética de seu sorriso e de algumas ausências dentárias. O indivíduo utilizava uma PPR provisória inferior insatisfatória e apresentava perda de dimensão vertical de oclusão (DVO). Após o exame clínico, radiográfico e estudo do caso em articulador semi-ajustável, realizou-se o planejamento com abordagens restauradoras, endodônticas, periodontais e protéticas. Após tratamento periodontal, foi realizada endodontia dos elementos 12, 15 e 47, confecção de núcleos e coroas nos dentes 12 e 15, restauração a nível gengival para apoio residual no dente 47, restaurações nos dentes 11, 13, 22, 24 e 44 e, por fim, a confecção das PPRs superior e inferior. A abordagem multidisciplinar utilizada neste caso clínico viabilizou o restabelecimento da DVO e possibilitou o sucesso da reabilitação protética(AU)

Removable partial dentures (RPDs) are a viable treatment alternative in clinical practice to rehabilitate partially edentulous arches. However, the planning of these dentures and prior oral preparation are often neglected. This article aims to report the clinical case of an oral rehabilitation with upper and lower RPDs after a multidisciplinary approach, to emphasize the phases of careful planning and prior preparation of the abutment teeth, aiming at the success and longevity of the rehabilitation. A 57-year-old male patient came to the clinic of the Bauru School of Dentistry, University of São Paulo, complaining about the esthetics of his smile and some missing teeth. The subject was using an unsatisfactory lower provisional prosthesis and had a loss of vertical dimension of occlusion (OVD). After the clinical and radiographic examination and the case study in a semi-adjustable articulator, planning was carried out with restorative, endodontic, periodontal and prosthetic approaches. After periodontal treatment, endodontics were performed on elements 12, 15 and 47, creation of cores and crowns on teeth 12 and 15, restoration at the gingival level for residual support on tooth 47, restorations on teeth 11, 13, 22, 24 and 44 and, finally, the making of the upper and lower PPRs. The multidisciplinary approach used in this clinical case enabled the restoration of the OVD and enabled the success of the oral rehabilitation(AU)

Envelhecimento bucal precoce e suas consequências para a cavidade oral com foco em reabilitação com resina composta: relato de caso / Early oral aging and its consequences for the oral cavity focusing on rehabilitation with composite resin: case report

O envelhecimento bucal precoce apresenta cada vez uma maior incidência nos consultórios odontológicos e sua degradação aos tecidos orais exige uma atenção por parte do cirurgiãodentista devido ao seu alto grau de complexidade. Esse envelhecimento precoce é causado principalmente por hábitos parafuncionais, dieta ou ambos. Suas consequências são desgastes patológicos dos tecidos dentários, extrusão passiva, perda de dimensão vertical e comprometimento estético e funcional. Por conta disso, o presente estudo teve como objetivo realizar um relato de caso clínico em um paciente jovem e com queixa estética como consequência de hábitos parafuncionais, aonde foram realizados uma reabilitação oral envolvendo aumento da dimensão vertical de oclusão através de Table Tops sem desgastes dentários e restaurações estéticas, ambas com resina composta. Essa reabilitação devolveu a DVO da paciente, trazendo conforto, contatos estáveis, guias de desoclusão e satisfação estética e funcional por parte da paciente(AU)

Early oral aging has an increasing incidence in dental offices and its degradation to oral tissues requires attention from the dentist due to its high degree of complexity. This premature aging is mainly caused by parafunctional habits, diet, or both. Its consequences are pathological wear of dental tissues, passive extrusion, loss of vertical dimension and aesthetic and functional impairment. Because of this, the present study aims to carry out a clinical case report in a young patient with an aesthetic complaint as a result of parafunctional habits, where an oral rehabilitation was carried out involving an increase in the vertical dimension of occlusion through Table Tops without dental wear and aesthetic restorations, both with composite resin. This rehabilitation returned the patient's OVD, bringing comfort, stable contacts, disocclusion guides and aesthetic and functional satisfaction on the part of the patient(AU)

Bite force changes after surgical correction of mandibular prognathism in subjects with increased vertical dimension : A prospective clinical trial.

PURPOSE: Occlusal bite force (OBF) is the most important parameter in assessing biting efficiency. The aim of this study was to record OBF changes after surgical correction of high angle maxillary/mandibular (Max/Mand) class III patients and to compare these with that recorded in class III patients with average Max/Mand angle. MATERIALS AND METHODS: Initially included were 42 patients with severe class III skeletal malocclusion who were scheduled for orthodontic surgery: group 1-22 patients with increased vertical relationship scheduled for bimaxillary surgery; group 2-20 patients with average vertical relationship scheduled for mandibular setback only. OBF measurements before surgery (T0), at debonding (T1) and at least 3 months after debonding (T2) were recorded using a portable occlusal force gauge. The following were also measured: maximum OBF (MOBF) achieved by the subject on each side, averaged OBF on each side (AOBF) and maximum OBF at the incisal region (MIOBF). At T2, only 33 patients (group 1: 17 and group 2: 16) were included in the analysis due to loss to follow-up. RESULTS: MOBF increased significantly in group 1, while no significant changes were detected in group 2. MIOBF increased after surgical correction in both groups. Significant increase in MIOBF was observed at T1 (P < 0.001) followed by an insignificant decrease during the observation period (3-6 months after treatment; P > 0.05). The two groups differed significantly in MOBF at T1 and T2, while no statistically significant differences were detected between the groups for MIOBF changes at the various time intervals (P > 0.05). The number of posterior teeth with occlusal contacts increased in both groups. Relapse was detected in group 1 where the number of posterior teeth in contact decreased during the observation period (T1-T2). CONCLUSION: OBF greatly improved after surgical correction of the vertical morphology. Correction of high angle mandibular prognathism improves oral function in addition to esthetics.

Prosthetic management of partial anodontia with microdontia from 11 to 20 years of age - 10 years of follow up.

Treatment of pediatric patients with partial anodontia is a challenge requiring interdisciplinary approach. Growth period, reduced vertical dimension, microdontia, and unacceptable esthetics present difficulties at various stages of prosthetic rehabilitation. Congenital absence of teeth impairs the nutritional status of the growing child and causes a psychological setback. This article describes the prosthetic management of a patient suffering from partial anodontia done over a period of 10 years. Considering the age and psychological and financial requirements of the patient, removable and fixed prostheses were fabricated at different phases of the treatment. The ultimate aim was restoration of function, improvement of esthetics, and overall psychological upliftment of the patient which was achieved by maxillary metal ceramic bridge and mandibular implant retained hybrid prosthesis.

Correlation between vertical dimension of occlusion and different facial measurements among a sample of sudanese adults / Correlación entre la dimensión vertical de la oclusión y diferentes medidas faciales en una muestra de adultos sudaneses

Aim: This study aimed to evaluate the correlation between vertical dimension of occlusion (VDO) and various facial measurements in a sample of Sudanese adults. Material and Methods: A total of 113 dental students (33 males and 80 females) with a mean age of 21.7±1.26 years were enrolled in this study. Different facial measurements including (Eye-Mouth, Eye-Eye, Eye-Ear, and Ear Height) were compared with two different measurements of VDO: N-Gn (from the tip of the nose to the tip of the chin), and Sn-Me (from the base of the nose to the bottom of the chin). Pearson's correlation coefficient test was utilized for the correlation between the measured parameters. A p-value of less than 0.05 was considered significant for all analyses. Results: A significant positive correlation was shown between all measured facial distances and both measured VDO distances. Though, the strongest correlation was seen for the eye-mouth distance (r= 0.725, p<0.001), while the weakest was for ear height (r= 0.254, p= 0.007). A paired t-test revealed a significant longer N-Gn distance than Sn-Me distance. Also, it has been shown that there were no significant differences between right and left sides of the face. Conclusion: The distance measured from the outer canthus of the eye to the angle of the mouth can be used to predict Subnasale-Menton (Sn-Me) distance.

Objetivo: Este estudio tuvo como objetivo evaluar la correlación entre dimensión vertical oclusal (DVO) y varias medidas faciales en una muestra de adultos sudaneses. Material y Métodos: Un total de 113 estudiantes de odontología (33 hombres y 80 mujeres) con una edad media de 21,7 ± 1,26 años se inscribieron en este estudio. Se compararon diferentes medidas faciales que incluyen (ojo- boca, ojo-ojo, ojo-oído y altura de la oreja) con dos medidas diferentes de DVO: N-Gn (desde la punta de la nariz hasta la punta del mentón) y Sn -Yo (desde la base de la nariz hasta la parte inferior del mentón). Se utilizó la prueba del coeficiente de correlación de Pearson para la correlación entre los parámetros medidos. Un valor de p inferior a 0,05 se consideró significativo para todos los análisis. Resultados: Se mostró una correlación positiva significativa entre todas las distancias faciales medidas y ambas distancias DVO medidas. Sin embargo, la correlación más fuerte se observó para la distancia ojo-boca (r=0,725, p<0,001), mientras que la más débil fue para la altura de las orejas (r=0,254, p=0,007). Una prueba de t pareada reveló una distancia N-Gn significativamente más larga que la distancia subnasal-mentón. Además, se ha demostrado que no hubo diferencias significativas entre los lados derecho e izquierdo de la cara. Conclusión: La distancia medida desde el canto externo del ojo hasta el ángulo de la boca puede utilizarse para predecir la distancia subnasal-mentón.

Effect of occlusal coverage depths on the precision of 3D-printed orthognathic surgical splints.

BACKGROUND: Precise orthognathic surgical splints are important in surgical-orthodontic treatment. This study aimed to propose a standardized protocol for three-dimensional (3D)-printed splints and assess the precision of splints with different occlusal coverage on the dentition (occlusal coverage depth, OCD), thus optimizing the design of 3D-printed splints to minimize the seemingly unavoidable systematic errors. METHODS: Resin models in optimal occlusion from 19 patients were selected and scanned. Intermediate splints (ISs) and final splints (FSs) with 2-mm, 3-mm, 4-mm, and 5-mm OCDs were fabricated and grouped as IS-2, IS-3, IS-4, IS-5, FS-2, FS-3, FS-4, and FS-5, respectively. The dentitions were occluded with each splint and scanned as a whole to compare with the original occlusion. Translational and rotational deviations of the lower dentition and translational deviations of the landmarks were measured. RESULTS: For vertical translation, the lower dentitions translated inferiorly to the upper dentition in most of the splints, and the translation increased as OCD got larger. Vertical translations of the dentitions in 89.47% of IS-2, 68.42% of IS-3, 42.11% of IS-4, 10.53% of IS-5, 94.74% of FS-2, 63.16% of FS-3, 26.32% of FS-4, and 21.05% of FS-5 splints were below 1 mm, respectively. For pitch rotation, the lower dentitions rotated inferiorly and posteriorly in most groups, and the rotation increased as OCD got larger. Pitch rotations of the dentitions in 100% of IS-2, 89.47% of IS-3, 57.89% of IS-4, 52.63% of IS-5, 100.00% of FS-2, 78.95% of FS-3, 52.63% of FS-4, and 47.37% of FS-5 splints were below 2°, respectively. On the other hand, the transversal and sagittal translations, roll and yaw rotations of most groups were clinically acceptable (translation < 1 mm and rotation < 2°). The deviations of ISs and FSs showed no statistical significance at all levels of coverage (P > 0.05). CONCLUSIONS: A protocol was proposed to generate 3D-printed ISs and FSs with normalized basal planes and standardized OCDs. Deviations of the ISs and FSs were more evident in the vertical dimension and pitch rotation and had a tendency to increase as the OCD got larger. ISs and FSs with both 2-mm and 3-mm OCD are recommendable regarding the precision relative to clinical acceptability. However, considering the fabrication, structural stability, and clinical application, ISs and FSs with 3-mm OCD are recommended for accurate fitting.

Relapse patterns of two-jaw surgical correction in patients with skeletal Class III malocclusion and different vertical facial types.

The aim of this study was to evaluate postoperative relapse after the surgical correction of skeletal Class III deformities of various facial patterns as a guide to surgical planning. A retrospective cohort study of 90 consecutive patients with skeletal Class III malocclusion who underwent bimaxillary surgery was performed. The surgical outcomes and postoperative stability were compared. The primary predictor variable was vertical facial type, which was classified into three groups according to the Frankfort mandibular plane angle (FMA). The primary outcome of angular and linear measurements was obtained using serial cone beam computed tomography scans obtained at time points of preoperative, 1 week after surgery, and orthodontic debonding. No significant difference in skeletal relapse was observed in patients with the different vertical facial types. The mandible displayed a forward and upward relapse in all three groups postoperatively. The patients with a low FMA exhibited a more consistent mandibular relapse pattern than those with a normal or high FMA. These findings suggest that bimaxillary surgery is clinically stable for mandibular prognathism regardless of the vertical facial pattern. However, 1-1.5 mm of overcorrection in the mandible setback should be considered in patients with a low FMA, because of the greater facial depth and consistent forward and upward mandibular relapse pattern.

Dimensión vertical de la cara en adultos con diferentes relaciones oclusales / Vertical dimension of face in adults with different Angle class

RESUMEN: Se ha postulado que la posición postural mandibular (PPM) no presentaría la menor actividad electromiográfica (EMG) de los músculos masetero y temporal, y que esta menor actividad se encontraría en una apertura mayor. El objetivo de este estudio fue analizar la PPM en pacientes con diferentes relaciones oclusales y según tipo de método de posicionamiento, relacionándolo con la actividad EMG de los músculos Masetero y Temporal, además del registro de la actividad EMG en diferentes aperturas orales. Se analizó una muestra de 25 adultos de 18 a 28 años. Estos fueron clasificados según su sexo y clasificación de Angle. Se realizaron simultáneamente registros de EMG de superficie -masetero y porción anterior del temporal- y de EMA -posición de la mandíbula respecto al maxilar obteniendo distancia y ángulo- en diferentes posiciones mandibulares: PPM-considerando método sin comando y de deglución- y apertura gradual hasta alcanzar la máxima apertura. Se realizó un análisis estadístico descriptivo. La menor PPM obtenida fue de 1,0 ± 0,6 mm en mujeres Clase III y utilizando la técnica sin comando; el mayor fue de 2,5 ± 0,2 mm en mujeres Clase II y utilizando la técnica de deglución. La apertura angular presentó menor variabilidad que las distancias lineales. La actividad de los músculos Maseteros derecho e izquierdo presentaron valores similares entre sí, al igual que en los rangos de apertura hasta 30 mm en hombres y mujeres y en las diferentes relaciones oclusales. La actividad de los Temporales para hombres y mujeres y en las diferentes relaciones oclusales mostraron variaciones importantes entre derecha e izquierda y en los diferentes grados de apertura. La técnica presentada permitió el estudio de la dimensión vertical y aperturas orales a través de EMA y EMG.

SUMMARY: It has been postulated that the mandibular postural position (MPP) could not present the lower electromyographic activity (EMG) of the Masseter and Temporal muscles, and that the lower activity could be found in a larger opening. The objective of this study was to analyze the PPM in patients with different occlusal relationships and according to the positioning method, relating it to the EMG activity of the Masseter and Temporal muscles, in addition to recording the EMG activity in different oral openings. A sample of 25 adults aged 18 to 28 years was analyzed. Participants were classified according to their sex and Angle classification. Simultaneous recordings of surface EMG -Masseter and anterior portion of the Temporal- and EMA -position of the Mandible with respect to the Maxilla obtaining distance and angle- were performed in different mandibular positions: PPM-considering the method "without command" and "swallowing"- and gradual opening until the maximum opening is reached. A descriptive statistical analysis was performed. The lowest PPM obtained was 1.0 ± 0.6 mm in Class III women and using the "without command" method; the largest was 2.5 ± 0.2 mm in Class II women and using the "swallowing" method. The angular opening presented less variability than the linear distances. The activity of the right and left masseter muscles presented similar values, as well as in the opening ranges up to 30 mm in men and women and in the different occlusal relationships. The activity of the Temporals for men and women and in the different occlusal relationships showed important variations between right and left and in the different degrees of opening. The presented technique allowed the study of the vertical dimension and oral openings through EMA and EMG.

Nasopharyngeal structure development in patients with cleft palate who underwent repair surgery.

OBJECTIVE: This study aimed to compare the developmental characteristics of bony nasopharyngeal (NP) in children with cleft palate (CP) and non-cleft subjects. METHODS: This study was conducted on 64 non-syndromic CP patients who underwent repair surgery and 23 non-cleft subjects as controls. Lateral cephalograms were performed on participants at rest in the natural head position. The X-coordinate and the Y-coordinate of three points on cephalograms were determined as Hormion (Ho), posterior maxillary point (PMP) and anterior point of the atlas (At) representing the anterior-posterior (AP) and vertical dimension of the NP. The linear dimension of the NP (i.e. Ho-At, Ho-PMP, At-PMP) and its area was also calculated. RESULTS: The bony structures of NP in the clef-affected subjects in isolated CP subgroup, had a significantly greater downward development in the maxillary region (PMP) (both with p = 0.001), more linear growth in cranial-maxillary (Ho-PMP) dimension (p = 0.017 and 0.004, respectively), and larger area (p = 0.017 and <0.001, respectively), when compared to normal subjects. There was no significant difference between either the unilateral cleft lip and palate (CLP) or bilateral CLP group with the control group regarding AP, vertical, and linear growth of the NP and its area (P > 0.05). CONCLUSIONS: Patients with repaired CP had downward deviated posterior maxilla, more linear growth in cranial-maxillary dimension and larger area compared to normal subjects. Among CP subtypes, a balanced growth was observed among repaired UCLP and BCLP patients, suggesting that with appropriate repaired surgery, normal development of the NP region could be expected in these subtypes.

Restabelecimento da Dimensão Vertical de Oclusão com JIG estético modificado e Prótese Parcial Removível Overlay: relato de caso / Reestablishment of occlusal vertical dimension with a modified aesthetic JIG and an overlay removable partial denture: a case report

A reabilitação de pacientes parcialmente edêntulos com desgaste dentário severo e dimensão vertical de oclusão reduzida é desafiadora e complexa. Objetivo: Descrever o restabelecimento da dimensão vertical de oclusão e parâmetros estéticos com uma prótese parcial removível do tipo overlay (PPRO) com auxílio de um JIG estético modificado. Relato de caso: Paciente do sexo masculino, 58 anos de idade, procurou serviço odontológico queixando-se de insatisfação com a estética do sorriso e perda dos dentes posteriores. Ao exame clínico, foram observados desgaste dentário excessivo e edentulismo parcial nas arcadas superior e inferior. Então, foi proposto tratamento em 2 etapas (provisória e definitiva) com PPRO em maxila. O JIG estético foi usado como guia de referência para incrementos em resina composta fotopolimerizável e o restabelecimento da dimensão vertical de oclusão foi determinado a partir de métodos métrico, fonético e estético. Os dentes desgastados foram aumentados e os dentes ausentes substituídos por dentes artificiais a partir de uma PPRO provisória. Após 2 meses de adaptação, a reabilitação final com PPRO definitiva foi conduzida baseando-se na reabilitação com a PPRO provisória. Conclusão: O paciente relatou satisfação com a estética e desempenho funcional com o tratamento. Portanto, o JIG estético beneficia o planejamento e o tratamento para restabelecer a dimensão vertical de oclusão. Além disso, a PPRO é uma alternativa reversível, de baixo custo, para reabilitar a estética e a função de pacientes com desgaste severo e perda parcial dos dentes.

The rehabilitation of partially edentulous patients with severe tooth wear and reduced occlusal vertical dimension is challenging and complex. Objective: To describe the reestablishment of occlusal vertical dimension and aesthetic parameters with an overlay re-movable partial denture (ORPD) with the aid of a modified aesthetic JIG. Case report: A 58-year-old man sought dental service complaining of dissatisfaction with the aesthetics of his smile and a loss of posterior teeth. At clinical examination, excessive tooth wear and partially edentulism in the lower and upper arches were observed. A two-step treatment (interim and definitive) with an ORPD in the upper arch was proposed. The aesthetic JIG was used as a reference guide for the increments in light-curing resin composite, and the reestablishmentthe occlusal vertical dimension was determined using aesthetic, phonetic, and metric methods. The worn teeth were increased, and the missing natural teeth were replaced by artificial teeth using a temporary ORPD. After two months of adaptation, de-finitive rehabilitation with a definitive ORPD was performed based on the interim ORPD. Conclusion: The patient reported satisfaction with the esthetic and functional performance of this treatment. Therefore, the aesthetic JIG benefits the planning and treatment of reduced vertical dimension. Moreover, the ORPD is a reversible and lower-cost alternative to rehabilitate the aesthetics and function of patients with severe teeth wear and partial teeth loss.

Efeitos de customizações da prótese total mandibular sobre a qualidade de vida, força de mordida e eletromiografia de músculos da mastigação de pacientes edêntulos: um estudo clínico analítico intervencional / Effects of mandibular complete denture customizations on quality of life, bite force, and masticatory muscle electromyography in edentulous patients: an interventional analytical clinical study

Objetivo: Avaliar se customizações da prótese total mandibular (reembasamento e restabelecimento da dimensão vertical de oclusão) influenciam na amplitude eletromiográfica dos músculos masseter e temporal, força máxima de mordida e qualidade de vida relacionada à saúde oral de indivíduos edêntulos. Materiais e métodos: Usuários de próteses totais que usavam o mesmo par de próteses por mais do que 5 anos foram incluídos (sem disfunção temporomandibular) (n=15). Avaliações de qualidade de vida (Oral Health Impact Profile for Edentulous ­ OHIP-EDENT), força máxima de mordida, e eletromiografia dos músculos masseter e temporal foram realizadas em 5 tempos diferentes (T1 ­ próteses antigas originais; T2 ­ após 18 dias de uso da prótese mandibular reembasada; T3 ­ após 18 dias do restabelecimento da dimensão vertical de oclusão; e T4 e T5 ­ 30 e 100 dias de uso de novas próteses totais. Resultados: Não houve diferenças significativas entre os pontos de tempo para todos os testes eletromiográficos e de força máxima de mordida. O OHIP-EDENT mostrou que o reembasamento pode contribuir para uma maior adaptação da prótese total mandibular e conforto do paciente (T2), em contrapartida T3 foi associado com o desconforto do paciente (p<0.05). Conclusão: Baseado na avaliação de qualidade de vida relacionada à saúde oral, o reembasamento da prótese total mandibular ocasionou um aumento do conforto mastigatório para os pacientes, e o restabelecimento prévio da dimensão vertical de oclusão causou um desconforto para os pacientes. A amplitude eletromiográfica mostrou que as customizações realizadas neste estudo não aumentaram ou diminuíram o esforço mastigatório significativamente. Além disso, todos os valores de força máxima de mordida observados estavam dentro do clinicamente aceitável(AU)

Objective: To evaluate whether customizations of mandibular complete dentures (relining and restoration of the vertical dimension of occlusion) influence the electromyographic amplitude of the masseter and temporal muscles, maximum bite force and oral health-related quality of life of edentulous individuals. Materials and methods: Complete denture wearers who wore the same pair of dentures for more than 5 years were included (without temporomandibular dysfunction) (n=15). Assessments of quality of life (Oral Health Impact Profile for Edentulous ­ OHIP-EDENT), maximum bite force, and electromyography of the masseter and temporal muscles were performed at 5 different times (T1 - original old dentures; T2 - after 18 days of wearing relined mandibular denture; T3 - after 18 days of restoration of the vertical dimension of occlusion; and T4 and T5 - 30 and 100 days of wearing new complete dentures. Results: There were no significant differences between the time points for all electromyographic and maximum bite force tests. The OHIP-EDENT showed that relining can contribute to greater adaptation of the mandibular denture and patient comfort (T2), in contrast, T3 was associated with patient discomfort (p<0.05). Conclusion: Based on the assessment of quality of life related to oral health, the reline of the mandibular complete denture caused an increase in masticatory comfort for the patients, and the previous definitive restoration of the vertical dimension of occlusion caused discomfort for patients. The electromyographic amplitude showed that the customizations performed in this study did not significantly increase or decrease masticatory effort. In addition, all observed maximum bite force values were within the clinically acceptable range(AU)

A surgery-first approach using single-jaw rotational mandibular setback in low-angle mandibular prognathism.

For the treatment of low-angle mandibular prognathism, rotational mandibular setback surgery is usually performed with Le Fort I maxillary osteotomy to rotate the maxillomandibular complex simultaneously. However, this maxillary surgery can be replaced with the orthodontic intrusion of maxillary posterior teeth. Single-jaw rotational mandibular setback surgery can be done with a surgery-first approach by planning orthodontic rotation of the maxillary occlusal plane with the simulation of the postsurgical forward mandibular rotation. This case report describes this approach applied to a 19-year-old female patient with low-angle mandibular prognathism but without maxillary deficiency. A Class II open bite was formed by the rotational setback surgery. During postsurgical orthodontic treatment, the maxillary total arch was distalized with maxillary molar intrusion using palatal mini-implants and lever. This case report demonstrates that orthodontic rotation of the maxillary occlusal plane and simulation of mandibular rotation can replace maxillary surgery and enable single-jaw rotational mandibular setback surgery with a surgery-first approach.

Application of the Digital Articulator in Surgery-First Approach.

ABSTRACT: Orthognathic surgery with surgery-first concept inevitably leads to an increase in posterior vertical dimension and anterior mandibular movement, causing a relapse. This case report introduces a digital technique for predictable surgical outcome in mandibular setback with the surgery-first orthognathic concept using digital articulator. Intraoral scans and a digital articulator were used to simulate the mandibular position after surgery and to predict postoperative increase in vertical dimension and its expecting forward movement of mandibile. This was incorporated in surgical planning. Sequential cone-beam computed tomography evaluation showed stable condylar position at 3 and 6 months after surgery. Thus, a digital articulator can be used to simulate the surgical outcome and to predict postsurgical increase in vertical dimension for better treatment planning.

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.

Accuracy of Mandible-First versus Maxilla-First Approach and of Thick versus Thin Splints for Skeletal Position after Two-Jaw Orthognathic Surgery.

BACKGROUND: The aim of this study was to investigate the accuracy of bimaxillary orthognathic surgery regarding different sequencing (maxilla-first or mandible-first surgery) and different thicknesses of intermediate splints. METHODS: This retrospective cohort study evaluated the accuracy of postoperative outcome in accordance with virtual planning in 57 patients requiring bimaxillary osteotomies with different operation sequence: maxilla-first (n = 31) or mandible-first (n = 26) surgery. The effect of different splint thicknesses (i.e., thick, n = 22; and thin, n = 35) was also evaluated. The 1-week postoperative cone-beam computed tomographic craniofacial images were superimposed onto preoperative simulated images to measure the discrepancy of the three-dimensional cephalometric landmarks. RESULTS: Neither sequencing approach differed in overall accuracy (1-week postoperative to preoperative simulated image discrepancy): maxilla-first, 1.69 ± 0.53 mm; versus mandible-first, 1.44 ± 0.52 mm. In detailed comparison, mandible-first surgery resulted in more accuracy in the vertical dimension. Thick intermediate splints provided better control (less error) of upper central incisors in the sagittal position (thick splint, 1.38 ± 1.17 mm; thin splint, 2.13 ± 1.38 mm). However, overall accuracy was not affected by splint thickness. Conditions affecting sequencing predilection included skeletal class III with vertical excess, maxillary down-grafting, counterclockwise rotation of the maxillomandibular complex, and simulated mandibular opening for splint fabrication clearance. CONCLUSIONS: Despite both means of sequencing being performed similarly, mandible-first surgery was more precise in the vertical dimension. Thick intermediate splints seemed to yield better control of central incisors in the sagittal position. However, under appropriate selection of intermediate splints to maintain interim condylar position, splint thickness has no effect on overall accuracy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Cephalometric evaluation of changes in vertical dimension and molar position in adult non-extraction treatment with clear aligners and traditional fixed appliances

ABSTRACT Introduction: Orthodontists have been using clear aligners to treat malocclusions, and one potential effect of treatment with orthodontic aligners is the intrusion and/or resists extrusion of the posterior teeth. This "bite-block effect" is primarily anecdotal due to the frequent occurrence of posterior open bites in patients after clear aligner therapy. Objective: The purpose of this study was to compare changes promoted by clear aligners and traditional fixed appliances in cephalometric measurements of the vertical dimension and molar position in adult patients with Class I malocclusion treated with non-extraction. Methods: Pre- and post-treatment lateral cephalometric radiographs of adult patients treated with either clear aligners (n=44) or traditional fixed appliances (n=22) were selected for retrospective analysis. Eight interval measurements and one nominal measurement were evaluated: anterior overbite (OB), mandibular plane angle related to cranial base (SN_MP) and related to Frankfort (FMA), lower molar height (L6H) and upper molar height (U6H), palatal plane to mandibular plane angle (PP_MP), lower facial height (LFH), total facial height (TFH), and posterior open bite (Posterior_OB). A single evaluator traced all cephalographs, and changes in select measures of the vertical dimension were compared within and between groups. Results: OB decreased (1.15 mm) and L6H increased (0.63 mm) in the traditional fixed appliance group. Mandibular plane angles (related to cranial base and to Frankfort) increased (0.43° and 0.53°, respectively) in the clear aligner group, but just FMA showed significant difference between groups (difference of 0.53°). LFH and TFH increased (ranging from 0.52 mm to 0.80 mm) in both groups, with no differences between treatment modality. Presence of visible posterior open bite significantly increased over the course of treatment. OB, FMA and L6H exhibited an interaction between treatment stage (pre- and post-treatment) and modality (clear aligner therapy and traditional fixed appliances), but no interaction among these three variables was found. Conclusions: The evidence does not support the theory that clear aligner therapy produces better vertical dimension control than traditional fixed appliances. Traditional fixed appliance therapy slightly extruded the lower molar, and clear aligner therapy produced a slightly mandibular backward rotation.

RESUMO Introdução: Ortodontistas têm usado os alinhadores transparentes para tratar más oclusões, e um potencial efeito desse tratamento é a intrusão e/ou resistência à extrusão dos dentes posteriores. Esse efeito de "bloco de mordida" é principalmente empírico, devido à ocorrência frequente de mordidas abertas posteriores em pacientes após a terapia com alinhadores transparentes. Objetivo: O objetivo do presente estudo foi comparar as mudanças promovidas pelos alinhadores transparentes e aparelho fixo convencional nas medidas cefalométricas de dimensão vertical e posição do molar em pacientes adultos com má oclusão de Classe I tratados sem exodontias. Métodos: Radiografias cefalométricas laterais pré- e pós-tratamento de pacientes adultos tratados com alinhadores transparentes (n=44) ou com aparelho fixo tradicional (n=22) foram selecionadas para uma análise retrospectiva. Oito medidas de intervalo e uma medida nominal foram avaliadas: trespasse vertical anterior (OB), ângulo do plano mandibular em relação à base do crânio (SN_MP) e em relação ao Plano de Frankfurt (FMA), altura do molar inferior (L6H) e altura do molar superior (U6H), ângulo do plano palatal ao plano mandibular (PP_MP), altura facial inferior (LFH), altura facial total (TFH) e mordida aberta posterior (Posterior_OB). Um único avaliador fez todos os traçados cefalométricos, e as mudanças nas medidas da dimensão vertical foram comparadas intra e intergrupos. Resultados: OB reduziu (1,15 mm) e L6H aumentou (0,63 mm) no grupo de aparelho fixo tradicional. Os ângulos do plano mandibular (em relação à base do crânio e ao plano de Frankfurt) aumentaram (0,43° e 0,53°, respectivamente). No grupo dos alinhadores invisíveis, apenas o FMA apresentou diferença significativa entre os grupos (diferença de 0,53º). LFH e TFH aumentaram (variando de 0,52 mm a 0,80 mm) em ambos os grupos, sem diferenças entre as modalidades de tratamento. A presença de uma mordida aberta posterior visível aumentou significativamente durante o curso do tratamento. OB, FMA e L6H exibiram interação entre o estágio do tratamento (pré- e pós-tratamento) e a modalidade (terapia com alinhadores invisíveis ou aparelho fixo tradicional), porém não foi encontrada interação entre essas três variáveis. Conclusões: A evidência não suporta a teoria de que a terapia com alinhadores invisíveis produz melhor controle da dimensão vertical do que o aparelho fixo. O tratamento com aparelhagem fixa extruiu ligeiramente o molar inferior, e o tratamento com alinhadores invisíveis produziu uma ligeira rotação posterior da mandíbula.

Relación entre la dimensión vertical oclusal y la longitud lineal del pabellón auricular / Relationship between occlusal vertical dimension and linear ear length

Resumen Introducción: La dimensión vertical oclusal en algunos casos se altera y para predecirla se suelen utilizar métodos, tanto subjetivos como objetivos y entre los que se encuentran los antropométricos. Objetivo: Evaluar la correlación entre la longitud lineal del pabellón auricular y la dimensión vertical en jóvenes dentados. Métodos: Se evaluaron 47 estudiantes a nivel de la longitud vertical del pabellón auricular (punto más superior al punto más inferior del lóbulo de la oreja), medición del canto exterior del agujero ocular al tragus y la dimensión vertical oclusal (situados en el punto subnasal y en el borde más prominente del mentón). Todas las mediciones se hicieron con un calibrador digital. Resultados: La dimensión vertical oclusal promedio fue de 65,68 ± 4,14 mm. La distancia promedio entre el canto externo del ojo al tragus derecho fue de 67 ± 3,52mm (correlación de r = 0,776; p < 0,01) mientras que en el lado izquierdo fue de 66,95 ± 3,98 mm (correlación de r = 0,733; p < 0,01). La distancia de la longitud del pabellón auricular en el lado derecho fue de 64,74 ± 4,47mm (correlación de r = 0,643; p < 0,01) mientras que en el lado izquierdo fue de 64,84 ± 4,46 mm (correlación de r = 0,657; p < 0,01). Conclusiones: Las medidas antropométricas de la longitud lineal del pabellón auricular derecho e izquierdo se correlacionó con la dimensión vertical oclusal así como la medición entre el canto externo del ojo al tragus también se correlación con la dimensión vertical oclusal(AU)

ABSTRACT Introduction: When occlusal vertical dimension becomes altered, as is sometimes the case, use should be made of subjective and objective methods, including those based on an anthropometric approach. Objective: Evaluate the correlation between linear ear length and vertical dimension in dentate young subjects. Methods: A total 47 students were evaluated for linear vertical ear length (from the highest to the lowest end of the earlobe), and measurements were taken from the outer edge of the ocular hole to the tragus and the vertical occlusal dimension (located at the subnasal point and the most prominent edge of the chin). All measurements were taken with a digital caliper. Results: Average vertical occlusal dimension was 65.68 ± 4.14 mm. Average distance from the outer edge of the eye to the right tragus was 67 ± 3.52 mm (r correlation = 0.776; p < 0.01), whereas on the left side it was 66.95 ± 3.98 mm (r correlation = 0.733; p < 0.01). Ear length distance was 64.74 ± 4.47 mm on the right side (r correlation = 0.643; p < 0.01) and 64.84 ± 4.46 mm on the left side (r correlation = 0.657; p < 0.01). Conclusions: Right and left linear ear length anthropometric measurements correlated with vertical occlusal dimension. The distance from the outer edge of the eye to the tragus also correlated with the vertical occlusal dimension(AU)

Postsurgical changes of mandible based on vertical dimension increase in Skeletal Class III deformities.

The aim of this study was to evaluate the postsurgical mandibular changes after surgery based on vertical dimension increase in skeletal Class III deformities. Patients who underwent mandibular setback surgery for skeletal Class III malocclusion correction with surgery-first orthognathic treatment were enrolled in the study. Lateral cephalograms were obtained at initial visit, immediately after surgery, 6 months after surgery, and at post-treatment. Postsurgical change of the mandible based on the vertical dimension increase was estimated using a diagrammatic method before surgery and this amount was compared with the actual amount of mandibular forward movement at 6 months after the surgery, using a paired t-test and Bland-Altman plot. Thirty patients (16 men and 14 women; mean age, 22.6 years) with skeletal Class III deformities had undergone mandibular setback surgery with the surgery-first orthognathic treatment. Immediately after surgery, the mandible setback was 9.4 ± 3.7 mm at pogonion. Six months after surgery, the mandible moved forward at an average of 2.3 ± 1.5 mm which corresponded to the estimated value of 2.2 ± 0.9 mm. The estimated amount of postsurgical movement did not show a statistically significant difference from the actual value on paired t-test (p = 0.349). The Bland-Altman analysis showed that the difference between the two values was within the limits of agreement. The postsurgical changes based on vertical dimension increase in surgery-first orthognathic treatment might be predicted by using a diagrammatic method.