Morphological analysis of mandibular anterior alveolar bone in high-angle adult females assessed with cone-beam computed tomography / 口腔疾病防治

Objective@#To investigate the features of alveolar bone morphology of mandibular central incisors in high-angle adult females using cone-beam computed tomography (CBCT) and evaluate the influence of aging in these patients.@*Methods@# CBCT and lateral cephalometric images of 142 untreated adult female patients were selected and grouped by facial growth pattern. The number of high-angle cases was increased to 164 to further explore the difference within high-angle adult females who were divided into two groups according to age. The indexes of alveolar bone height and thickness in the lower incisor region and inclination of the lower incisors were measured by Dolphin software. The data was statistically analyzed.@*Results@#Compared with the average-angle group, the high-angle group had a lower alveolar bone attachment level (P < 0.05) and less bone thickness at the root apex level (P < 0.05). The thickness of lingual alveolar bone decreased with labial inclination of the lower incisors in both the high-angle and average-angle groups (r = -0.251, P = 0.025; r = -0.428, P = 0.001, respectively). In hyperdivergent female patients, the middle-aged group had a lower attachment level of alveolar bone than the young group (P < 0.05), but no significant difference in bone thickness at the root apex level (P > 0.05) was found between the two groups@*Conclusion @# High-angle adult females had thinner mandibular anterior alveolar bone with significantly lower attachment levels. Aging and inclination of lower incisors influenced bone morphology and should be taken into careful consideration.

Estabilidad: Análisis de la inclinación del incisivo inferior luego del tratamiento ortodóncico / Stability: Analysis of the inclination of the lower incisor after orthodontic treatment

Este trabajo de investigación tiene como finalidad comparar la inclinación del incisivo inferior pre y post-tratamiento en pacientes tratados ortodóncicamente con técnicas Roth y técnica Damon a los cuales no se les realizó exodoncias. El grupo de estudio estuvo conformado por 150 pacientes adultos con dentición permanente completa que han sido atendidos en el Círculo Argentino de Odontología. Para medir la inclinación se utilizó la fórmula de Tweed: ángulo IMPA, eje axial del incisivo inferior con el plano mandibular. Los valores tomados de los trazados pre y post-tratamiento fueron sometidos a un test de Student apareado utilizando el programa Infostat v 2010. Se encontró una diferencia significativa en la inclinación axial del incisivo inferior post tratamiento cualquiera sea la técnica utilizada, aumenta en ambos casos. No se realizó discriminación de torques (Roth ­ 1°, Damon torque estándar ­ 3°, Damon bajo torque - 11°) (AU)

This research work aims to compare the inclination of the lower incisor before and after treatment in patients treated orthodontically with Roth techniques and Damon technique to which no exodontics were performed. The study group consisted of 150 adult patients with complete permanent dentition who have been treated in Circulo Argentino de Odontología. To measure the inclination the Tweed formula was used: IMPA angle, axial axis of the lower incisor with the mandibular plane. The values taken from the pre and post-treatment plots were subjected to a Student test paired using the Infostat v 2010 program. A significant difference was found in the axial inclination of the lower incisor post treatment whatever the technique used, it increases in both cases. No torques discrimination was performed (Roth - 1 °, Damon standard torque - 3 °, Damon under torque - 11 °) (AU)

Lower incisor changes following non-extraction orthodontic decompensation in Class III surgical cases

@#The amount of incisor decompensation during pre-surgical orthodontics may affect the outcome of Class III orthognathic cases. The purpose of this study was to assess the lower incisor changes post-orthodontic decompensation in Class III surgical cases and to investigate the amount of crowding as a predictive factor. This was a retrospective study reporting on 22 Class III orthognathic cases. The lower incisor angulation (LIA) and distance of the lower incisor edge to the A-Pogonion line (Li-APo) were measured on pre-treatment and presurgical lateral cephalograms whereas crowding was measured on digitised pre-treatment study models. Pearson’s correlation (p <0.05) was used to assess the correlation of crowding with LIA and Li-APo changes, and prediction of the lower incisor decompensation was conducted using linear regression analysis. Results showed lower incisors were retroclined at 79.84° ± 7.08° and positioned ahead of APo line by 6.52 mm ± 2.97 mm at the start of treatment. Pre-surgical LIA and Li-APo were found to increase following orthodontic decompensation to 90.43° ± 5.96° and 10.34 mm ± 3.25 mm, respectively. There was a moderate positive correlation (r = 0.592) between crowding and Li-APo changes which was statistically significant, p value = 0.004, and had a strong predictor with 31.8% predictability. However, LIA showed a weak correlation (r = 0.329) with crowding and was not statistically significant (p = 0.135). Li-APo changes during orthodontic decompensation can be predicted with 31.8% predictability using the formula; Li-APo change = 2.064 + 0.503 (crowding).

Tratamiento ortodóncico en paciente adulta con Periodontitis crónica controlada / Orthodontic treatment in an adult patient with controlled chronic periodontitis

RESUMEN Introducción: En pacientes adultos con periodontitis el tratamiento de Ortodoncia constituye un reto, por las condiciones biomecánicas que impone la edad, y el estado de afectación del periodonto; principal responsable de los movimientos ortodóncicos. Objetivo: Describir el tratamiento ortodóncico realizado en paciente adulta con periodontitis crónica controlada y los resultados conseguidos. Presentación del caso: Paciente femenina de 41 años, con periodontitis crónica tratada. Diastemas y extrusión en incisivos, pérdida de la inserción periodontal y exposición del cemento radicular. Apiñamiento incisivo inferior, con extrusión e incremento de la curva de Spee. Trauma oclusal interincisivo. El plan de tratamiento incluyó control de la periodontitis, la extracción de un incisivo inferior y la intrusión dentaria incisiva bimaxilar. El tratamiento duró año y medio. Los resultados fueron excelentes. Se devolvió la función perdida; se consiguió incrementar la inserción periodontal, con la consiguiente disminución de la movilidad dentaria. Se corrigió la estética afectada y se obtuvo la satisfacción de la paciente. Conclusiones: A partir de la aplicación del tratamiento de Ortodoncia se consiguió corregir las anomalías de posición dentarias y de la oclusión, devolver a la paciente adulta portadora de periodontitis crónica la estética perdida y una oclusión funcional. Las decisiones terapéuticas consideraron el estado del periodonto, el control de la enfermedad y la edad de la paciente. Las fuerzas aplicadas fueron extremadamente controladas y el tiempo de tratamiento el menor posible. La motivación y el cuidado de la higiene bucal contribuyeron a los resultados alcanzados.

ABSTRACT Introduction: The orthodontic treatment is a challenge in adult patients with periodontitis because of the biomechanical conditions imposed by age and the state of involvement of the periodontium, which is the main responsible for orthodontic movements. Objective: To describe the orthodontic treatment performed in an adult patient with controlled chronic periodontitis and to show the results obtained. Case Presentation: Forty-one years old female patient with chronic periodontitis. She presented diastemas and incisors extrusion, loss of periodontal insertion and exposure of the root cement, lower incisor crowding with extrusion and increase of the curve of Spee. She also had interincisive occlusal trauma. The treatment plan included the control of periodontitis, the removal of a lower incisor and the intrusion of bimaxillary incisor. The treatment lasted a year and a half. The results were excellent. The lost function was restored and periodontal insertion was increased with the consequent decrease in tooth mobility. The affected aesthetics was corrected obtaining patient satisfaction. Conclusions: From the application of the orthodontic treatment, it was possible to correct the dental position and occlusion anomalies and give the patient back the lost esthetics and a functional occlusion. Therapeutic decisions considered the state of the periodontium, the control of the disease and the age of the patient. The applied forces were extremely controlled and the treatment time was as short as possible. The motivation and care of oral hygiene contributed to the results achieved.

Inclination of lower incisors among the female patients with beautiful profiles in different vertical skeletal types / 实用医学杂志

Objective To study the differences in the inclination of lower incisors among the female patients with beautiful profiles in different vertical skeletal types so as to provide the clinical treatment design for a certain guiding. Methods 137 cephalometric films of female patients with beautiful profiles were selected and divided into three groups based on the vertical facial types(∠SNMP):small degree(n = 31),average degree(n = 89) and larger degree groups(n=17). The angles of∠L1/MP and∠L1/A-Pog were measured and treated with covari-ance analysis for detecting the differences between the groups. Results The index of L1-MP(°)was the smallest in the larger degree group,the largest in the small degree group and average in the average group,with significant differences between the three groups(F = 17.38,P 0.05). Conclusion Lower incisors have compensatory inclined lingually in the group of higher mandible angle,but labially in the group of lower mandible angle.

Manejo ortodôntico da agenesia de incisivo inferior / Orthodontic management of lower incisor agenesis

O sucesso do tratamento de pacientes com agenesia de incisivo inferior depende dos fatores dentários, esqueléticos e faciais associados. No planejamento considerações estéticas e funcionais são importantes para a escolha da forma de tratamento mais apropriado, quer seja a adequação da oclusão dentária ou a reabilitação protética do espaço deixado pela ausência. Esse artigo tem como objetivo descrever duas formas de abordagem para correção dos vários aspectos decorrentes da agenesia de um incisivo inferior. Pode-se concluir que a agenesia de incisivos inferiores pode comprometer a oclusão dentária, o desenvolvimento alveolar anterior inferior, a região de sínfise mandibular, a estética facial e o equilíbrio funcional lábio-lingual. O diagnóstico precoce e planejamento adequado do tratamento envolvendo equipe multidisciplinar podem produzir resultados favoráveis, evitando o impacto negativo da ausência congênita na qualidade de vida da criança pela redução dos sintomas bucais e limitação funcional, promovendo seu bem-estar emocional e social.( AU)

Treatment success of patients with lower incisor agenesis depends on associated dental, skeletal and facial factors. When planning, aesthetic and functional considerations are important for choosing the most appropriate form of treatment, whether it is the adequacy of dental occlusion or the prosthetic rehabilitation of the space left by the absence. This article aims to describe two approaches to correct the various aspects resulting from the lower incisor agenesis. We can conclude that agenesis of lower incisors may compromise dental occlusion, lower anterior alveolar development, mandibular symphysis region, facial aesthetics and lip-tongue functional balance. Early diagnosis and adequate treatment planning involving a multidisciplinary team can produce favorable results, avoiding the negative impact of congenital absence on the child's quality of life through reduction of oral symptoms and functional limitation, promoting his/her emotional and social well-being.. (AU)

Angle Class I malocclusion treated with lower incisor extraction

In planning orthodontic cases that include extractions as an alternative to solve the problem of negative space discrepancy, the critical decision is to determine which teeth will be extracted. Several aspects must be considered, such as periodontal health, orthodontic mechanics, functional and esthetic alterations, and treatment stability. Despite controversies, extraction of teeth to solve dental crowding is a therapy that has been used for decades. Premolar extractions are the most common, but there are situations in which atypical extractions facilitate mechanics, preserve periodontal health and favor maintenance of the facial profile, which tends to unfavorably change due to facial changes with age. The extraction of a lower incisor, in selected cases, is an effective approach, and literature describes greater post-treatment stability when compared with premolar extractions. This article reports the clinical case of a patient with Angle Class I malocclusion and upper and lower anterior crowding, a balanced face and harmonious facial profile. The presence of gingival and bone recession limited large orthodontic movements. The molars and premolars were well occluded, and the discrepancy was mainly concentrated in the anterior region of the lower dental arch. The extraction of a lower incisor in the most ectopic position and with compromised periodontium, associated with interproximal stripping in the upper and lower arches, was the alternative of choice for this treatment, which restored function, providing improved periodontal health, maintained facial esthetics and allowed finishing with a stable and balanced occlusion. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO), as part of the requirements for obtaining the BBO Diplomate title.

No planejamento ortodôntico de casos que incluem extrações como alternativa para solucionar o problema de discrepância de espaço negativa, a decisão crítica é determinar quais dentes serão extraídos. Devemos considerar vários aspectos, como a saúde periodontal, mecânica ortodôntica, alterações funcionais e estéticas, e estabilidade do tratamento. Apesar das controvérsias, a extração de dentes para solucionar apinhamentos dentários é uma terapêutica que tem sido utilizada há décadas. As extrações de pré-molares são as mais comuns, mas há ocasiões em que extrações atípicas facilitam a mecânica, preservam a saúde periodontal e favorecem a manutenção do perfil, que tende a se alterar desfavoravelmente devido às modificações faciais decorrentes da idade. A extração de um incisivo inferior, em casos bem selecionados, é uma abordagem eficiente; e a literatura descreve maior estabilidade pós-tratamento, quando comparada com a opção de extração de pré-molares. O presente artigo relata um caso clínico de uma paciente com má oclusão de Classe I de Angle e apinhamento anterior superior e inferior, face equilibrada e perfil harmonioso. A presença de recessões gengivais e ósseas limitava grandes movimentações ortodônticas. Os molares e pré-molares estavam bem relacionados, e a discrepância concentrava-se principalmente na região anterior da arcada dentária inferior. A extração de um incisivo inferior em posição mais ectópica e com periodonto comprometido, associada a desgastes interproximais nas arcadas superior e inferior, foi a alternativa de escolha para o tratamento, que restabeleceu a função, proporcionando melhoria da saúde periodontal, manteve a estética facial, e permitiu a finalização com uma oclusão estável e equilibrada. Esse caso foi apresentado à diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO), como parte dos requisitos para obtenção do título de Diplomado pelo BBO.

A comparative study of pre- and post-treatment cephalometric measurements: Upper premolar extraction only vs. upper/lower premolar extraction groups / 대한치과교정학회지

OBJECTIVE: The objective of this study was to provide guidelines for the diagnosis and successful treatment of orthodontic treatment with upper premolar extraction only. METHODS: The sample group consisted of 40 patients (20 with upper premolar extraction only, 20 with both upper and lower premolar extractions) who showed an overjet of more than 7 mm and were finished successfully. Lateral cephalographs were taken before and after orthodontic treatment. Landmarks showing the position of the upper and lower incisors and the position of the upper and lower lip were determined and angular measurement of these values were obtained for statistical analysis (Mann-Whitney test). RESULTS: At pre-treatment, the position of the lower incisor was less labially inclined and the convexity of the lower lip was smaller in the upper premolar extraction only group than in the upper/lower premolar extraction group. At post-treatment, there was no difference in all measurements except for the position of the lower incisor. A comparison of changes between pre- and post-treatment showed that the retraction of upper & lower incisors and the decrease in convexity of the lower lip were greater in the upper/lower premolar extraction group. CONCLUSIONS: Treatment by upper premolar extraction can be of benefit for patients whose lower incisor proclination and lower lip protrusion are not excessive.

The long-term stability of the lower incisor axis in Class II division 2 malocclusions / 대한치과교정학회지

The purpose of this study was to evaluate the post-retention stability of the lower incisor axis in Class II division 2 malocclusions. The dental casts and lateral cephalograms from before (T1) and after (T2) orthodontic treatment and long-term post-retention (T3) in 62 Class II division 2 malocclusion cases were included in this study. After several linear and angular measurements at each time were taken, the significance in the amount of change of the lower incisor axis for each gender and extraction versus non-extraction was evaluated. The results showed that the lower incisors that inclined labially during treatment were unstable and relapsed to the original lingual position in Class II division 2 malocclusions (p 0.05). There was no significant difference between male and female groups for the axial change of the lower incisors (p > 0.05). As a result of multiple regression analysis, the cephalometric measurement best predicting the lower incisor position to the A-Pog line post-retention was pre-treatment L1-Apog(mm) and pre-treatment SNGoMe(degrees ). Because of the instability of labially inclined lower incisors after orthodontic treatment, the treatment goal should be the pre-treatment incisor axial position.

Dentoalveolar compensation according to skeletal discrepancy in Normal occlusion / 대한치과교정학회지

The purpose of this study was to investigate the dentoalveolar compensation according to anteroposterior skeletal discrepancy in normal occlusion and to evaluate cephalometric parameters that quantitatively describe dental compensations. The study consisted of 90 subjects (50 males, 40 females) who were selected among specimens of normal occlusion at Seoul National University Dental Hospital, Dept. of Orthodontics. Lateral cephalograms in centric occlusion were traced and digitized for each subject. According to the anteroposterior skeletal pattern, the sample was divided into three groups. Cephalometric data were analyzed for the three groups using the SPSS program. Independent t-test, correlation analysis and regression analysis were carried out. The results were as follows: Dentoalveolar compensation was found in upper and lower incisor inclination and occlusal plane inclination. As the mandible located anterior to the maxilla, the maxillary incisors inclined more labially, the mandibular incisors more lingually, and the occlusal plane continued to flatten. The dental parameters most correlated with anteroposterior skeletal discrepancy were L1 to SN and L1 to FH. Among the compensatory dentoalveolar changes, lower incisor inclination was strongly related to the anteroposterior jaw relationship and played an important role in obtaining a normal incisor relationship. U1 to PtGn and L1 to APog were constant irrelevant to anteroposterior skeletal discrepancy.

Orthodontic treatment of malocclusions by lower incisor extraction / 实用口腔医学杂志

Objective:To investigate the indications of lower incisor extraction in orthodontic treatment of malocclusions. Methods:42 patients (males 16,females 26) were divided into four groups: abnormal Bolton index; class III malocclusions with anterior teeth cross bite; one congenital lower incisor losing; and anterior teeth area periodontal disease.One lower incisor extraction, one lower incisor and other teeth extraction and other accessorial therapy were used in the treatment. Results:According to these four different conditions, alternative treatment plans of lower incisor extraction should be determined. For the former two conditions, one lower incisor was extracted; A lower incisor and two maxillary first premolars were extracted in the third condition, in which lower canines and first premolars should be grinded to improve esthetics; In the last condition, some maxillary teeth need stripping besides extracting one lower incisor. All of the 42 cases achieved satisfactory results, normal overbite and overjet and stable occlusal relationship. Conclusion:To be well acquainted with the indications of the extraction of the lower incisor in orthodontic treatment of malocclusions can help to achieve satisfactory clinical effect.