Prevalencia de anomalías dentomaxilares y necesidad de tratamiento de ortodoncia en niñas/os de 6 años en cinco comunas de Chile. Estudio Preliminar

Objetivo: Determinar la prevalencia de las anomalías dentomaxilares (ADM) y necesidad de tratamiento de ortodoncia en escolares de 6 años en cinco comunas en Chile. Material y método: Estudio de corte transversal, observacional y descriptivo. La muestra fue de 1102 escolares. Se realizaron exámenes clínicos aplicando la Guía de Referencia Clínica a Ortodoncia para Servicios Públicos de Salud, para determinar la prevalencia de las ADM y necesidad de tratamiento de ortodoncia. El análisis estadístico utilizó el programa STATA®, considerando estadísticamente significativo p 0.05. Resultados: 1102 escolares de 6 años fueron examinados, 48,8% niñas y 51,2% niños. La prevalencia de niño/as con anomalías dentomaxilares fue 59.1%. Las tres más prevalentes fueron: apiñamiento dentario o rotaciones (21,6%), resalte aumentado (17,6%) y overbite aumentado (15,9%). La necesidad de tratamiento de ortodoncia encontrada fue de 34,7% con evidente necesidad y un 25,3% con leve necesidad. Conclusión: Se evidencia la necesidad de incluir en las políticas públicas de salud oral, estrategias de diagnóstico y tratamiento temprano de ADM por su alta prevalencia.

Objective: To determine the prevalence of dento-maxillary anomalies (DMA) and the orthodontic treatment need in 6-year-old schoolchildren in five areas of Chile. Material and method: Cross-sectional, observational and descriptive study. The sample consisted of 1102 6-year-old schoolchildren. Clinical examinations were carried out applying the Clinical Reference Guide for Orthodontics in Public Health Services, to determine the prevalence of DMA and the need for orthodontic treatment. Statistical analysis used the STATA® program, considering p ≤ 0.05 statistically significant. Results: 1102 6-year-old children were examined, 48.8% were girls and 51.2% boys. The prevalence of children with DMA was 59.1%. The three most prevalent were: dental crowding or rotations (21.6%), increased overjet (17.6%), and increased overbite (15.9%). The orthodontic treatment need was 34.7% of patients with great need and 25.3% with moderate need. Conclusion: The need to include early diagnosis and treatment strategies for DMA in public oral health policies is evident due to its high prevalence.

Variabilidad en la medición del ángulo ANB de Steiner entre estudiantes de odontología y ortodoncia. Medición del Angulo ANB de Steiner

Introducción: El ángulo ANB de Steiner entrega la relación entre el maxilar y la mandíbula en sentido anteroposterior y es una de las medidas cefalométricas más aplicadas en ortodoncia. Su identificación precisa podría presentar dificultades, influyendo directamente en el posterior estudio cefalométrico, diagnóstico y plan de tratamiento. El objetivo de esta investigación fue comparar la medición del ángulo ANB de Steiner entre estudiantes de pregrado de odontología y postítulo de ortodoncia de la Facultad de Odontología de la Universidad de Chile 2020. Materiales y Métodos: Por medio del programa Adobe Photoshop CS6 (Adobe System ®), se solicitó a los estudiantes la identificación de los puntos Nasion, A y B en 5 telerradiografías laterales de cráneo. Al aplicar los criterios de inclusión y exclusión se reclutaron 15 estudiantes de cada grupo. Luego se unieron los puntos mediante trazados, se midió el ángulo ANB de Steiner y se utilizó el coeficiente de correlación intraclase (ICC) para determinar el grado de acuerdo. Resultados: Se encontró un coeficiente de correlación intraclase ICC promedio de 0.97 entre ambos grupos de estudiantes. Conclusión: No hay diferencia estadística en la determinación del ángulo ANB de Steiner entre estudiantes de pregrado de odontología y postítulo de ortodoncia.

Background: The Steiner ANB angle measures the relationship between the maxilla and mandible in the anteroposterior direction and is one of the most applied cephalometric measurements in orthodontics. Its precise identification could pose difficulties, directly influencing the subsequent cephalometric study, diagnosis and treatment plan. The aim of this research was to compare the measurement of the Steiner ANB angle between dental student and postgraduate students in orthodontics from the Faculty of Dentistry of the University of Chile 2020. Materials and Methods: Using the Adobe Photoshop CS6 program (Adobe System ®), the students were asked to identify the Nasion, A and B points in 5 lateral cephalogram of the skull. By applying the inclusion and exclusion criteria, 15 students were recruited from each group. The points were then joined by tracing, the Steiner ANB angle was measured, and the intraclass correlation coefficient (ICC) was used to determine the degree of agreement. Results: An average ICC intraclass correlation coefficient of 0.97 was found between both groups of students. Conclusion: T here is no statistical difference in the determination of the Steiner ANB angle between undergraduate students of dentistry and postgraduate students of orthodontics.

Manejo Ortodóncico Quirúrgico de la Displasia Cleidocraneal en Pacientes en Crecimiento

El objetivo de este estudio fue describir las alternativas terapéuticas ortodóncico-quirúrgicas más utilizadas en la actualidad para el manejo de la displasia cleidocraneal en pacientes en crecimiento. Se realizó una búsqueda de literatura durante mayo de 2023 en las bases de datos Pubmed, Epitemonikos, Dentistry & Oral Sciences Source y LILACS sobre reporte de casos que presentaran estrategias de tratamiento ortodóncico-quirúrgico en pacientes menores de 18 años con displasia cleidocraneal. Seis artículos cumplieron con los criterios de inclusión. De ellos se obtuvieron siete reportes de casos. Las edades de los pacientes fluctúan entre los 10 y 16 años. Las estrategias de tratamiento consisten en al menos dos etapas de tratamiento ortodóncico quirúrgicas que involucran la extracción de dientes primarios y supernumerarios y la exposición quirúrgica de dientes permanentes retenidos para permitir su erupción y/o su tracción ortodóncica. Algunos casos son finalizados con cirugía Ortognática (Osteotomía Le Fort I de avance maxilar). La extracción de dientes primarios y supernumerarios, fenestración y tracción ortodóncica de los dientes permanentes retenidos y la cirugía ortognática al finalizar el crecimiento (cuando sea necesario) se propone actualmente como la mejor alternativa terapéutica para el tratamiento de pacientes con displasia cleidocraneal.

The objective of this study was to describe the orthodontic-surgical therapeutic alternatives most used nowadays, for the management of CCD in growing patients. A literature search for case reports was carried out through May, 2023 in PubMed, Epitemonikos, Dentistry & Oral Sciences Source and LILACS databases. We included case reports that presented complete orthodontic-surgical treatment strategies in patients with DCC under 18 years of age. Six articles met the inclusion criteria and seven case reports were identified. The age of cases ranged from 10 to 16 years. Treatment strategies consisted of at least two stages of surgical orthodontic treatment involving extraction of primary and supernumerary teeth and surgical exposure of impacted permanent teeth to allow spontaneous eruption or orthodontic traction. Some cases were completed with orthognathic surgery. Extraction of primary and supernumerary teeth, fenestration and orthodontic traction of retained permanent teeth and orthognathic surgery at the end of growth (when necessary) is currently proposed as the best therapeutic alternative for the treatment of patients with DCC.

Hipoclorito de Sodio como Agente Desproteinizante para Mejorar la Adhesión en Esmalte Hipomineralizado en Ortodoncia. Una Revisión Narrativa

Obtener una buena adhesión entre esmalte y bracket es un aspecto fundamental para el éxito del tratamiento en Ortodoncia. Algunos casos presentan desafíos en esta adhesión, especialmente cuando nos enfrentamos ante un esmalte con alteraciones como hipomineralizaciones, hipoplasias o fluorosis dental. Para sobreponer esta dificultad en la unión adhesiva se han propuesto diversas estrategias terapéuticas como es el uso de agentes desproteinizantes. El objetivo de esta revisión narrativa es describir el uso de hipoclorito de sodio como agente desproteinizante en dientes con alteraciones de esmalte para mejorar la adhesión en Ortodoncia. Se realizó una búsqueda bibliográfica en PubMed de los últimos 5 años. Se encontraron 116 artículos, de los cuales 23 cumplieron con los criterios requeridos y fueron seleccionados para la revisión. La desproteinización del esmalte con hipoclorito de sodio como paso previo al grabado ácido, es una estrategia útil en el proceso de cementación de aparatología de ortodoncia fija en dientes con alteraciones del esmalte. El uso de hipoclorito de sodio al 5,25 % es una alternativa de bajo co sto, no invasiva y eficiente para mejorar la fuerza de adhesión en pacientes con alteraciones del esmalte.

Obtaining good adhesion between enamel and bracket is a fundamental aspect for success in Orthodontics. Some cases present challenges in this adhesion, especially when we are faced with enamel with alterations such as hypomineralization, hypoplasia or dental fluorosis. To overcome this difficulty in adhesive bonding, various therapeutic strategies have been proposed, such as the use of deproteinizing agents. The objective of this study is to describe the use of sodium hypochlorite as a deproteinizing agent in teeth with enamel alterations to improve adhesion in Orthodontics. A bibliographic search was carried out in PubMed for articles within the last 5 years. In this study 116 articles were found, of which 23 met the required criteria and were selected for the review. Deproteinization of the enamel with sodium hypochlorite as a prior step to acid etching is an important stage in the cementation process of fixed appliances in orthodontics. The use of 5.25% sodium hypochlorite is a low-cost, non-invasive and efficient alternative to improve adhesion strength in patients with anomalies of tooth enamel.

Comparison of dental dimensions in models developed with digital procedures and plaster models / Comparación de dimensiones dentales en modelos desarrollados con procedimientos digitales y modelos en yeso

Aim: This study aimed to collect evidence on the validity and reliability of measurements obtained from digital impression techniques. Materials and Methods: This comparative study was conducted on 31 patients. Intraoral scanner was applied to all patients. For each patient, an alginate impression of the upper maxilla was taken and later the 3D digital model was extracted by dental cone-beam computed tomography (CBCT). For preparation of plaster models, alginate impressions were taken and immediately poured with dental stone. In the next stage, a comparison was performed among the intraoral scanner, CBCT, and plaster models in terms of tooth size, dental width, and intra-arch dimensions. Results: Measuring tooth size and intra-arch dimensions in digital images obtained from intraoral scanner and CBCT were in most cases lower than the results obtained in the plaster models but the differences between digital techniques and plaster models are not clinically noticeable. Conclusions: Digital systems including intraoral scanner and CBCT are acceptable for clinical use in terms of accuracy.

Objetivo: Este estudio tuvo como objetivo recopilar evidencia sobre la validez y confiabilidad de las mediciones obtenidas a partir de técnicas de impresión digital. Materiales y Métodos: Este estudio comparativo se realizó en 31 pacientes. A todos los pacientes se les aplicó escáner intraoral. Para cada paciente, se tomó una impresión de alginato del maxilar superior y posteriormente se extrajo el modelo digital 3D mediante Tomografía computarizada de haz cónico (CBCT) dental. Para la preparación de los modelos de yeso se tomaron impresiones de alginato y se vertieron inmediatamente con yeso dental. En la siguiente etapa, se realizó una comparación entre el escáner intraoral, CBCT y los modelos de yeso en términos de tamaño de diente, ancho dental y dimensiones intraarcada. Discusión: Se encontró que la apariencia microscópica de las células fusiformes era comparable en ambos grupos. Los resultados de la citometría de flujo demostraron expresiones comparables en ambos grupos, siendo las muestras positivas para CD90, CD73, CD105, HLA ABC y negativas para CD34, CD45 y HLA DR. Hubo variaciones en la expresión de los marcadores cuando se evaluaron los potenciales de diferenciación. Conclusión: Los sistemas digitales como el escáner intraoral y el CBCT son aceptables para uso clínico en términos de precisión.

Comparación Morfológica de Zonas de Inserción de Miniplacas Ortodóncicas en la Región Mandibular entre Edad, Sexo, Biotipo y Clase Esqueletal

El manejo del anclaje en los tratamientos de ortodoncia ha sido un reto constante, por lo que la utilización de miniplacas aparece como un rescate a esta interrogante. Determinar las diferencias morfológicas en la zona de inserción de miniplacas ortodóncicas en las regiones anterior y posterior mandibular, comparandolas entre edad, sexo, biotipo y clase esqueletal. Se estudiaron 40 registros de cone-beam de pacientes y se realizaron mediciones de grosor del hueso, donde se identificaron los sitios que permitan posicionar una miniplaca y fueron comparados entre sexo, grupos etarios, biotipo y clase esqueletal. Se observó diferencias significativas entre hombres y mujeres a nivel anterior mandibular, en los hombres se observaron mayores grosores óseos y corticales. No se observaron diferencias significativas entre pacientes adultos y jóvenes a nivel anterior mandibular, pero sí hubo diferencias a nivel mandibular posterior. La zona 3 mm debajo del 2do molar no es una zona confiable para la inserción de mini placas, ya que muchos de los pacientes no presentaban hueso en esa zona. Las miniplacas son un recurso seguro de anclaje las cuales deben ser adaptadas a cada paciente.

The anchorage management in orthodontic treatments has been a constant challenge, the use of miniplates may be a viable solution to this query. The objective of this study was to determine the morphological differences in the area of insertion of orthodontic miniplates in the anterior and posterior mandibular regions, comparing them between age, sex, biotype and skeletal class. In this analysis 40 cone-beam records of patients were studied, bone thickness measurements were carried out, the sites that allowed the positioning of a miniplate were identified and compared between sex, age groups, biotype and skeletal class. Significant differences were observed between men and women at the anterior mandibular level, in men greater bone and cortical thicknesses were observed. No significant differences were observed between adult and young patients at the anterior mandibular level, but there were differences at the posterior mandibular level. The area 3 mm below the 2nd molar was not a reliable area for the insertion of mini plates, since many of the patients had no bone in that area. Miniplates are a safe anchoring resource which must be adapted to each patient.

Biotipo facial y clasificación esquelética maxilomandibular en pacientes angolanos con anomalías dentomaxilofaciales

Fundamento las mediciones cefalométricas son un instrumento útil en la atención ortodóncica, pues junto a otras mediciones cefalométricas completan y guían el plan de tratamiento que el especialista puede trazar en función de la resolución de las anomalías dentomaxilofaciales. Objetivo determinar la comorbilidad entre el biotipo facial y la clasificación esquelética maxilomandibular en pacientes angolanos con anomalías dentomaxilofaciales. Métodos se realizó un estudio descriptivo transversal, en la Clínica Meditex, en Luanda, Angola, en el período agosto/2021-julio/2023. La población de estudio fue de 123 telerradiografías del perfil de pacientes con anomalías dentomaxilofaciales, ingresados en la consulta de Ortodoncia. Para el análisis de la telerradiografía de perfil se realizaron mediciones del cefalograma de Ricketts y de Steiner, y se utilizó el software Facad versión 3403. Se estudió la clasificación esquelética maxilomandibular (clase I, clase II, clase III) y el biotipo facial (dolicofacial, mesofacial, braquifacial). Resultados el 46,34 % de los pacientes presentó una clase II esquelética maxilomandibular. Mediante el índice VERT de Ricketts, el 49,59 % de los casos fue clasificado como dolicofacial, seguido del 42,27 % como braquifacial. El 83,60 % de los pacientes con biotipo dolicofacial se caracterizó por presentar una clase II esquelética maxilomandibular, y el 76,92 % de aquellos con biotipo braquifacial clasificó como clase III. Se encontró una asociación significativa entre el biotipo facial y la clasificación esquelética maxilomandibular (p= 0,000). Conclusiones en la mayoría de los pacientes con anomalías dentomaxilofaciales se evidenció una relación entre el biotipo dolicofacial y la clase II esquelética maxilomandibular, por lo que existe una comorbilidad entre ambas características esqueléticofaciales.

Foundation cephalometric measurements are a useful instrument in orthodontic care, since together with other cephalometric measurements they complete and guide the treatment plan that the specialist can draw up based on the resolution of dentomaxillofacial anomalies. Objective to determine the comorbidity between facial biotype and maxillomandibular skeletal classification in Angolan patients with dentomaxillofacial anomalies. Methods a cross-sectional descriptive study was carried out at the Meditex Clinic, in Luanda, Angola, from August/2021 to July/2023. The studied population was 123 patients' profile teleradiographs with dentomaxillofacial anomalies, admitted to the Orthodontic clinic. For the analysis of the profile teleradiography, measurements of the Ricketts and Steiner cephalogram were made, and the Facad software version 3403 was used. The maxillomandibular skeletal classification (class I, class II, class III) and the facial biotype (dolichofacial, mesofacial, brachyfacial) were studied. Results 46.34% of patients presented maxillomandibular skeletal class II. Using the Ricketts VERT index, 49.59% of cases were classified as dolichofacial, followed by 42.27% as brachyfacial. 83.60% of patients with dolichofacial biotype were characterized by having maxillomandibular skeletal class II, and 76.92% of those with brachyfacial biotype were classified as class III. A significant association was found between facial biotype and maxillomandibular skeletal classification (p= 0.000). Conclusions in the majority of patients with dentomaxillofacial anomalies, a relationship was evident between the dolichofacial biotype and the maxillomandibular skeletal class II, so there is a comorbidity between both skeletal-facial characteristics.

Effect of miniscrew placement height on the distribution of biological forces produced by clear aligner for mandibular molar distalization / 口腔疾病防治

Objective@#To explore the effect of different miniscrew placement heights on the distribution of biological forces produced by clear aligner combined with intramaxillary traction for mandibular molar distalization, to identify the miniscrew location that is conducive to the protection of lower anterior tooth anchorage and to provide a reference that can be used when designing clinical treatments.@*Methods@#Mimics, GeomagicStudio 2017, SolidWorks 2016, and Ansys workbench were used to establish finite element analysis models and perform mechanical analysis under the following six working conditions: working condition 1 was the control group without miniscrews; working conditions 2 to 5 had miniscrew in the buccal bone cortex between the first and second molars of the lower jaw 10 mm, 7 mm, 4 mm, and 1 mm from the top of the alveolar crest, respectively; working condition 6 had the miniscrew in the center of the buccal tongue at the anterior edge of the ascending branch of the lower jaw 5 mm above the occlusal plane.@*Results@#On the sagittal axis, miniscrew anchorage caused distal displacement of all teeth. Compared to the control group, in the miniscrew group, the displacement of the anterior molars exceeded that of the second molars. On the vertical axis, the result in the control group was similar to backward bending; the results in the miniscrew groups resembled the effect of a lever, lowering the lateral incisors and canines and raising the central incisors and first premolars. On the coronal axis, the second premolars and the first molars showed lingual displacement in the control group, and only the premolars and first molars showed lingual displacementin the miniscrew groups. The canines were the teeth that were most strongly affected by the change in miniscrew placement height.@*Conclusion@#The higher the miniscrew position is, the stronger the protective effect on the anterior anchorage. According to the miniscrew placement height, the mandibular arch should be properly narrowed, the central incisors and first premolars should be lowered, and the lateral incisors and canines should be raised when designing clinical treatments.

Soft and hard tissue changes of hyperdivergent class Ⅱ patients before and after orthodontic extraction treatment / 北京大学学报(医学版)

Objective:To investigate the hard and soft tissue changing trend and contributing factors of skeletal class Ⅱ hyperdivergent patients before and after orthodontic camouflage treatment by analyzing the cephalogram and the three dimensional(3D)facial scan data.Methods:Eighteen skeletal class Ⅱhyperdivergent adult female patients who finished camouflage orthodontic treatment were selected.Skele-tal and dental measurements were carried out with the cephalometric analysis before and after the treat-ment.3D facial data before and after orthodontic treatment were acquired and the anatomical landmarks were set after the repositioning and superimposition process.Hard tissue measurement included 17 mea-surement indicators(sella-nasion-subspinale angle,sella-nasion-supramental angle,subspinale-nasion-supramental angle,facial angle,angle of convexity,Frankfort horizontal plane-mandibular plane angle(FH-MP),Y axis angle,sella-nasion plane-mandibular plane angle(MP-SN),pogonion-nasion-supra-mental distance,upper incisor-nasion-subspinale distance,upper incisor to sella-nasion,lower incisor-nasion-supramental distance,lower incisor-nasion-supramental angle,upper incisor to lower incisor,up-per incisor to sella-nasion,lower incisor-mandibular plane angle,and Z angle),and the changes before and after treatment were measured for 11 of them.Twenty soft tissue landmarks(left/right cheekbone,left/right chelion,left/right crista philtra,soft tissue gnathion,left/right gonion,glabella,labrale infe-rius,labrale superius,soft tissue menton,left/right mid-mandibular border,soft tissue pogonion,stomi-on superius,sublabial,subnasale,and supralabial)and 9 soft tissue indicators(lower lip height,facial convexity,lower vermilion height,mandibular contour,nasolabial angle,philtral length,philtral width,upper lip height,and upper vermilion height)were measured and recorded for treatment changes.Linear-regression analysis and correlation analysis were carried out for analyzing the relationship between hard and soft tissue changes before and after the treatment.Results:Significant differences were noticed for 18 out of the 20 cephalometric measurements and facial measurements before and after the treatment(P＜0.05),which mainly represented the sagittal retraction of lip area after the treatment.Significant vertical displacements were revealed for soft tissue menton after treatment[(1.88±2.61)mm,P＜0.05].Significant sagittal displacements were revealed for left/right cheilion[(-2.95±1.9)mm,(-2.90±1.92)mm],labrale inferius[(-4.94±1.95)mm],labrale superius[(-3.25±1.44)mm],sublabial[(-3.10±3.5)mm],and subnasale[(-1.23±1.06)mm]after treatment(P＜0.05).An average of 4.10°±2.57° increasement was noticed for Z angle after treatment.High correla-tion(r＞0.7)was noticed for the displacement of menton after treatment with FH-MP,with the rate of-0.183:1,and MP-SN,with the rate of-0.157:1.Moderate correlations(0.7≥r＞0.4)were no-ticed for the other measurements with correlations(P＜0.05).Conclusion:A certain extent of facial improvements could be achieved with orthodontic camouflage treatment for skeletal class Ⅱ hyperdiver-gent patients,which were mostly represented by the improvement of sagittal relationship of nose,lips,and chin.Certain correlations were noticed for the hard and soft tissue changes.

Computer aided design of 3D dental segmentation and its application scenarios / 中国组织工程研究

BACKGROUND:Traditional 3D dental segmentation methods usually utilize predefined spatial geometric features,such as curvature and normal vectors,as the reference information for tooth segmentation. OBJECTIVE:To propose an algorithm for complex 3D dental segmentation and deeply explore the correlation between segmentation results and application scenarios. METHODS:A 3D dental segmentation algorithm based on dual stream extraction of structural features and spatial features was established,and the modular design of split flow was used to avoid feature confusion.Among them,the attention mechanism on the structural feature flow was used to capture the fine-grained semantic information required for tooth segmentation,and the Tran Net based on the spatial feature flow was used to ensure the robustness of the model to complex tooth and jaw segmentation.This algorithm verified its effectiveness and reliability based on clinical datasets including healthy dental jaws and complex dental jaws such as missing teeth,malocclusion and dentition crowding.The segmentation performance of the model was measured in terms of overall accuracy,mean intersection over union,and directional cut discrepancy. RESULTS AND CONCLUSION:The overall segmentation accuracy of this algorithm in the clinical data set is 97.08%,and the segmentation effect is superior to that of other competitive methods from the qualitative and quantitative perspectives.It is verified that the structural feature flow designed in this paper can extract more precise local details of tooth shape from coordinate and normal information by constructing an attention aggregation mechanism,and the spatial feature flow designed in this paper can ensure the robustness of the model to complex teeth such as missing teeth,dislocated teeth,and crowded dentition by constructing a transformation network(Tran Net).Therefore,this tooth segmentation algorithm is highly reliable for clinicians'practical reference.

Effects of enamel adhesives with different components on Porphyromonas gingivalis and Streptococcus mutans / 中国组织工程研究

BACKGROUND:The light curing and fluoride light curing enamel adhesives have a certain sealing effect on the etched enamel surface.The fluoride light curing enamel adhesives can also achieve the anti-caries function by releasing fluoride ions.However,the existing researches lack the long-term tracing of fluoride release effect,especially the amount of local pathogenic bacteria after 1-3 months of local fluoride application. OBJECTIVE:To analyze the changes in the expression of Porphyromonas gingivalis and Streptococcus mutans in subgingival plaque of the upper anterior teeth adhered by different components of enamel adhesives in adolescent patients with fixed appliance. METHODS:Ninety adolescent patients who received orthodontic treatment in Shanghai Stomatological Hospital from January to December 2016 were enrolled,including 43 males and 47 females,with a mean age of(13.27±1.12)years.These patients were randomly divided into three groups(n=30 per group).In the chemical curing group,Unite? bonding resin was used to bond fixed appliances.In the light curing group,Transbond XT light curing resin was used to bond the fixed appliance.In the fluoride light curing group,GC light curing orthodontic adhesive was used to bond the fixed appliance with cement.The subgingival plaque was collected on the day of bonding,1st,2nd,and 3rd month follow-up reviews.The expressions of Porphyromonas gingivalis and Streptococcus mutans in subgingival plaque were detected by PCR. RESULTS AND CONCLUSION:(1)Intragroup comparison:With the increase of bonding time,Porphyromonas gingivalis expression increased significantly in the 3rd month in the chemical curing group(P<0.05).In the light curing group,Porphyromonas gingivalis showed a significant decrease in the 1st month(P<0.05).Porphyromonas gingivalis expression decreased significantly in the 1st and 2nd months compared with initial data in the fluoride light curing group(P<0.05).The expression of Streptococcus mutans was higher in the chemical curing group in the 1st,2nd,and 3rd months compared with the initial data(P<0.05).In the fluoride light curing group,the expression of Streptococcus mutans was lower in the 1st,2nd,and 3rd months compared with the initial data(P<0.05).There was no significant difference in the proliferation and expression of Streptococcus mutans during follow-up in the light curing group compared to the initial adhesion(P>0.05).(2)Intergroup comparison:In the 1st month,the expression of Porphyromonas gingivalis was lower in the light curing group and fluoride light curing group than that in the chemical curing group(P<0.05).In the 2nd and 3rd months,the expression of Porphyromonas gingivalis was lower in the fluoride light curing group than that in the light curing group and chemical curing group(P<0.05).In the 1st,2nd,and 3rd months,the expression of Streptococcus mutans was lower in the light curing group and fluoride light curing group than that in the chemical curing group(P<0.05).The expression of Streptococcus mutans was lower in the fluoride light curing group than that in the light curing group(P<0.05).(3)The results show that in the fixed orthodontic process,the use of different components of enamel adhesives has different effects on the proliferation and expression of oral Porphyromonas gingivalis and Streptococcus mutans in the short term.Fluoride light curing enamel adhesives at the initial stage can reduce the occurrence of enamel demineralization,caries,and periodontal inflammation.

Biomechanical characteristics of orthodontic tooth movement before and after increasing alveolar bone mass with periodontally accelerated osteogenic orthodontics / 中国组织工程研究

BACKGROUND:There is an increasing demand for orthodontic treatment,and periodontally accelerated osteogenic orthodontics(PAOO)technique can make it possible to move orthodontic teeth that are limited by thin alveolar bone. OBJECTIVE:To investigate the biomechanics of orthodontic tooth movement before and after periodontally accelerated osteogenic orthodontics(PAOO)surgery to increase alveolar bone volume using the three-dimensional finite element method. METHODS:A patient undergoing PAOO surgery before orthodontic treatment to increase bone volume on the labial side of the mandibular anterior region was selected.The patient was under invisible orthodontics.Two three-dimensional finite element models were constructed based on the patient's preoperative and 6-month postoperative cone beam CT data.Both models simulated the movement of tooth 33:experiment Ⅰ:distal-central movement of 0.25 mm;experiment Ⅱ:lingual movement of 0.25 mm;and experiment Ⅲ:intrusion movement of 0.10 mm.The stress distribution and initial displacement trend of tooth 33,periodontal ligament and surrounding alveolar bone under the action of the invisible aligner were analyzed before and after the PAOO procedure. RESULTS AND CONCLUSION:Dental stress analysis:In the same orthodontic tooth movement,the maximum Von-Mises stress and overall stress values of tooth 33 were all higher before surgery than after surgery;there were similar distribution areas of maximum equivalent stress and overall distribution trends of Von-Mises stress before and after surgery.Periodontal ligament stress analysis:In the same orthodontic tooth movement,the maximum Von-Mises stress and overall stress values of the periodontal ligament were higher before surgery than after surgery,and there were similar distribution areas of the maximum equivalent stress and overall distribution trends of Von-Mises stress before and after surgery.Alveolar bone stress analysis:In the same orthodontic tooth movement,the maximum Von-Mises stress values of the alveolar bone around tooth 33 were higher before surgery than after surgery,while the equivalent stress distribution showed a gradual decrease from the top of the alveolar ridge to the root.Initial displacement analysis:In the same orthodontic tooth movement,the initial displacements in the main displacement direction for all six observation points of tooth 33 were smaller before surgery than after surgery,and showed a tendency to gradually decrease from the tooth tip to the apex.Therefore,there were differences in the biomechanical characteristics of orthodontic tooth movement before and after the PAOO surgery.With the clear aligner,the postoperative equivalent stress values on the dentition,periodontal ligament,and surrounding alveolar bone were lower than before the surgery,and the initial displacements of the orthodontic teeth after the surgery are larger than before.These findings suggest that PAOO can release the restriction of thin alveolar bone on the movement of orthodontic tooth by increasing alveolar bone thickness,effectively improving the force on the roots,periodontal ligament,and alveolar bone,avoiding the stress concentration on orthodontic tooth in the thin alveolar bone area that can cause complications when moving,and improving the efficiency of tooth movement.

The effects of invisible orthodontic appliances without brackets and labial fixed orthodontic appliances on periodontal status and root resorption in orthodontic patients / 中国医师杂志

Objective:To compare the effects of invisible orthodontic appliances without brackets and labial fixed orthodontic appliances on periodontal status and root resorption in orthodontic patients.Methods:A retrospective study was conducted on 102 orthodontic patients who visited the Affiliated Hospital of Jining Medical University from January 2019 to October 2022. According to different treatment methods, they were divided into group A ( n=52) and group B ( n=50). Group A was treated with invisible orthodontic appliances without brackets, while group B was treated with labial fixed orthodontic appliances. We compared two groups of treatment completion time, root resorption, and periodontal health indicators before and after treatment, including plaque index (PLI), gingival index (GI), gingival sulcus bleeding index (SBI), and levels of inflammatory factors in gingival crevicular fluid, including interleukin-1β (IL-1β) and soluble intercellular adhesion molecule-1 (sICAM-1). Results:The completion time of treatment in the Group A was longer than that in the group B [(34.62±4.28)months vs (28.93±3.11)months] ( P<0.01). After treatment, the incidence of root resorption in the group A was 50.96%, while in the group B it was 78.00%. The group A was significantly lower than the group B ( P<0.05), with no root resorption greater than 3 mm in the group A and 0.50% in the group B. After treatment, the levels of PLI, GI, SBI, and IL-1β and sICAM-1 in gingival crevicular fluid increased in both groups, with the group A being lower than group B [(1.26±0.39)points vs (1.73±0.54)points, (1.33±0.25)points vs (2.06±0.46)points, (1.73±0.40)points vs (2.48±0.50)points, (173.74±25.81)ng/ml vs (196.33±31.52)ng/ml, (42.28±5.16)μg/L vs (56.59±7.38)μg/L] (all P<0.05). Conclusions:Although invisible orthodontic appliances without brackets cannot shorten the completion time of treatment, they have advantages in inhibiting root resorption, improving periodontal health, and reducing inflammatory reactions. Clinically, appropriate appliances can be selected based on the specific situation of patients.

Prospects of ChatGPT in orthodontic education and clinical practice / 口腔疾病防治

@#In recent years, artificial intelligence (AI), such as image recognition and fixed-point and digital scanning, has been increasingly applied in dental orthodontics. ChatGPT is an emerging artificial intelligence technology that has attracted a considerable amount of attention from people of all walks of life since its introduction. This paper discusses the application potential of ChatGPT in the field of orthodontics from two perspectives—education and clinical practice—and analyzes its limitations. Current reports show that ChatGPT can improve the efficiency of teaching in orthodontic education as well as assist users in completing medical mock exams training, writing papers and conducting academic research, etc. In the clinic, ChatGPT can be used to engage patients in medical dialog, simplify clinical procedures and improve diagnostic and treatment efficiency. However, because ChatGPT is still in the early stages of research and application, there are problems such as insufficient data, inaccurate answers, and poor academic ethics and privacy. In the future, additional studies, training and optimization are needed to ensure the safety, ethics and benefit of AI, laying the foundation for improving the use of AI in the field of orthodontics.

Clinical effect of Piezocision combined with a microporous technique on periodontal tissue reconstruction during anterior displacement of mandibular molars in adults / 中国基层医药

Objective:To investigate the clinical effectiveness of Piezocision combined with a microporous technique in accelerating periodontal tissue reconstruction during the anterior migration of mandibular molars in adults.Methods:A prospective, randomized, controlled study was conducted on 30 adult orthodontic patients recruited from Shaoxing Hospital of Traditional Chinese Medicine between January 2020 and September 2022. The inclusion criteria were patients who were unable to retain their first molars due to severe caries or long-term absence and were not suitable for implantation. Using the random number table method, the patients were randomly assigned to two groups: a simple orthodontic control group (Group A, n = 15) and a group that received Piezocision combined with a microporous technique (Group B, n = 15). After treatment, a comparison was made between the two groups in terms of mesial movement distance of the mandibular second molar, plaque index, gingival index, periodontal pocket depth, width of keratinized gingiva, gingival recession, clinical attachment loss, mesial root resorption of the mandibular second molar, alveolar bone height (measured as the distance from the center of the lower incisor to the anterior margin of the chin, referred to as the LM-AC distance), mandibular bone height (measured by the distance from the distal or mesial surface of the root to the alveolar bone margin, denoted as the CEJ-AC distance), and orthodontic satisfaction. Results:The mesial movement distances of the mandibular second molar in Group A patients were (0.86 ± 0.13) mm, (2.75 ± 0.24) mm, (3.54 ± 0.24) mm, and (4.67 ± 0.13) mm at 4, 6, 8, and 12 weeks, respectively. These values were significantly greater than those observed in Group B, which were (0.43 ± 0.06) mm, (1.27 ± 0.14) mm, (1.85 ± 0.53) mm, and (2.65 ± 0.06) mm ( t = 6.83, 14.13, 18.24, 23.78, all P < 0.001). Prior to treatment, there were no statistically significant differences in plaque index, gingival index, periodontal pocket depth, width of keratinized gingiva, gingival recession, or clinical attachment loss between the two groups (all P > 0.05). After treatment, Group A did not exhibit statistically significant differences in plaque index, gingival index, width of keratinized gingiva, and gingival recession compared with baseline values (all P > 0.05). However, in Group A, periodontal pocket depth and clinical attachment loss significantly increased compared with pretreatment levels ( t = -2.57, -7.50, both P < 0.05). After treatment, Group B exhibited significantly increased values for periodontal pocket depth, width of keratinized gingiva, gingival recession, and clinical attachment loss compared with baseline levels ( t = -8.66, -5.57, -45.33, -9.72, all P < 0.001). Furthermore, these values were significantly higher in Group B compared with those in Group A ( t = -4.28, -3.18, 10.00, 10.69, all P < 0.001). A statistically significant difference was also observed between the two groups in terms of mesial root resorption of the mandibular second molar ( t = 4.14, P < 0.001). However, there was no statistically significant difference in LM-AC distance between the two groups after treatment ( P > 0.05). Conclusion:The combination of Piezocision and a microporous technique can effectively accelerate the anterior migration of mandibular molars in adults while maintaining the health of periodontal tissues. This approach holds great potential for clinical promotion.

Cone-beam computed tomography study of root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology in high-angle Class Ⅱ open bite patients / 口腔疾病防治

Objective@#This study aimed to explore the root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology in patients with high-angle skeletal Class Ⅱ open bite, aiming to provide a reference for clinical treatment.@*. Methods@#This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. CBCT images of eighty-one untreated patients (40 anterior open bite patients and 41 normal overbite patients) with high-angle skeletal Class Ⅱ malocclusion were selected before treatment. Dolphin software was used to study the root length of maxillary and mandibular anterior teeth and central incisor crown-root morphology, and the differences between the two groups were analyzed.@*Results@#There was no statistical significance in the root length of maxillary lateral incisor and canine between the open bite group and the normal overbite group, significant differences were found in the root length of maxillary central incisor （11.12 ± 1.37） mm、mandibular central incisor（10.15 ± 1.09）mm, mandibular lateral incisor（11.27 ± 1.15）mm and mandibular canine（12.81 ± 1.48）mm between the open bite group and the normal overbite group（P<0.05）. On the other hand, the two groups were significantly different in crown-root morphology of the maxillary central incisor (1.10° ± 3.62° vs. 4.53° ± 2.30°, P<0.01) but not in the mandibular central incisor.@*Conclusion@#The root length of the maxillary central incisor, mandibular central incisor, mandibular lateral incisor, mandibular canine in high-angle Class Ⅱ open bite patients is shorter than that in high-angle Class Ⅱ normal overbite patients, and the long axis of the crown of the maxillary central incisor in high-angle Class Ⅱ open bite patients obviously deviates toward the labial side relative to the long axis of the root. The crown-root angle is smaller, which is beneficial to torque control or adduction movement of the anterior teeth in high-angle Class Ⅱ open bite patients.

Study on the role of nano antibacterial materials in orthodontics (a review) / Estudo sobre o papel dos materiais nanoantibacterianos na ortodontia

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.

Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.

Study on the role of nano antibacterial materials in orthodontics (a review)

Abstract Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.

Resumo Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.

Effect of various educational methods on increasing parents' awareness of their children's preventive orthodontic treatments

Aim: Like other fields of health, the main focus in dentistry has shifted from treatment to prevention of diseases. Parents have a vital role in deciding about their children's oral health issues. This study aims to investigate the effectiveness of four educational methods (including printed pamphlets, digital pamphlets, faceto-face education, and educational films) in increasing the awareness of parents about preventive orthodontic treatments. Methods: The study samples were selected from patients who were referred to the Pediatric Dentistry Department. 150 parents of children between 4-12 years old participated in the study. They filled out a questionnaire including demographic data and knowledge about orthodontic problems and their early treatments. Then they were divided into five groups (control, printed pamphlet, digital pamphlet, face-to-face, educational films) and after one month they repeated the test. Results: A total of 102 fathers and 48 mothers were evaluated. There was no statistical difference between different ages, sex, or income in terms of their awareness, but the awareness score between educational groups was different. There has been observed a significant increase in the awareness level of all four groups (except the control group) (P < 0.05). The highest score was seen in the video group. The difference between printed pamphlets and digital pamphlets was not significant. Conclusions: The results indicate that educational films are the most effective way of increasing awareness about preventive orthodontic treatments

Evaluación del aparato funcional postratamiento de Waveney como alternativa en la contención del avance mandibular

Fundamento: Para la contención del avance mandibular es necesario utilizar un aparato que mantenga la mandíbula en la posición lograda por los aparatos activos y que su diseño no provoque movimientos dentarios indeseados. Objetivo: Describir los cambios clínicos y cefalométricos del aparato funcional postratamiento de Waveney como alternativa en la contención del avance mandibular. Metodología: Se realizó una investigación descriptiva observacional de corte transversal en el servicio Ortodoncia de la Clínica Estomatológica Docente Provincial Dr. Justo Ortelio Pestana Lorenzo de la provincia Sancti Spíritus, desde septiembre 2019 a febrero 2022. Se seleccionaron 20 pacientes que iniciaron su etapa de contención en este período y cumplieron los criterios de inclusión. Se utilizaron métodos del nivel empírico y estadístico. Se analizaron las variables: edad, sexo, variables morfológicas clínicas y cefalométricas, así como resultado de la contención. Resultados: Se constató una edad promedio de 15.6; el 65 % de los escolares pertenecían al sexo femenino. Al año de iniciada la contención se mantuvo el sobrepase incisivo en 2.95 mm, la relación molar de neutroclusión en el 65 %, ángulo SNB en 79°, el ángulo ANB en 2.80°, la posición del incisivo superior 2.45 mm, la posición del incisivo inferior en 1.90 mm y el perfil estético en 0.55 mm. Solo existió incremento en el valor promedio del resalte incisivo de 2.70 mm a 2.75 mm. Conclusiones: Al año de iniciada la contención con el aparato funcional postratamiento de Waveney no se observó modificación de las variables estudiadas, excepto el resalte incisivo con incremento de su valor promedio.

Background: For mandibular advancement containment, it is necessary to use an appliance that holds the jaw in the achieved position by active appliances and that its design does not provoke undesired dental movements. Objective: To describe the clinical and cephalometric changes of the Orthodontic Appliances after the Waveney treatment as an alternative in the mandibular advancement containment. Methodology: A descriptive observational cross-sectional research was conducted at the Dr. Justo Ortelio Pestana Lorenzo Provincial Teaching Stomatology Clinic orthodontic service in Sancti Spíritus province, from September 2019 to February 2022. 20 patients who started their containment stage in this period and fulfilled the inclusion criteria were selected. Empirical and statistical methods were used. The following variables were analyzed: age, sex, clinical morphological and cephalometric variables, as well as the containment result. Results: An average age of 15.6 was found; 65% of the schoolchildren were female. One year after the containment was started, the incisive overpass was maintained at 2.95 mm, the neutroclusion molar rate at 65%, SNB angle at 79°, the ANB angle at 2.80°, the upper incisor position 2.45 mm, the lower incisor position by 1.90 mm and the esthetic profile by 0.55 mm. There was only an average increase in the incisor protrusion value from 2.70 mm to 2.75 mm. Conclusions: One year after containment with the Waveney post-treatment Orthodontic Appliances was initiated no changes were observed in the studied variables, except for incisor protrusion with an increase in its average value.