Células tronco e endodontia regenerativa / Stem cells and regenerative endodontics

Desde o incremento das pesquisas das células-tronco em 1961, por cientistas canadenses, os avanços em estudos, pesquisas e o desenvolvimento de novos tratamentos com esse tipo de recurso se mostram promissores. O uso de células-tronco é uma grande aposta tanto para a medicina quanto para a odontologia regenerativa. Os tratamentos com essa terapia podem oferecer mais qualidade de vida para as pessoas. O potencial dessas células tão especiais se encontra em duas características peculiares: elas são capazes de se multiplicarem e de se diferenciarem em outros tipos de células, como de tecidos, cartilagens e neurônios. É dessa maneira que elas têm um papel fundamental para estudos e tratamentos relacionados à regeneração. O uso de células-tronco na Odontologia torna possível diferentes processos odontológicos que oferecem mais qualidade de vida ao paciente. Isso porque fatores como defeitos genéticos, hábitos nocivos, cáries dentárias e perdas precoces dos dentes contribuem com a perda de dentes ao longo da vida. No início do século XXI, por volta dos anos de 2005, 2006, pesquisadores começaram a publicar em revistas internacionais da área uma nova técnica baseada no uso de célulastronco existentes no osso de sustentação dos dentes e na articulação dento alveolar. Esta técnica, chamada de Revascularização, promove o aparecimento de um novo tecido pulpar sadio, devolvendo ao dente sua vitalidade e higidez(AU)

Since the increase in stem cell research in 1961 by Canadian scientists, advances in studies, research and the development of new treatments with this type of resource have shown promise. The use of stem cells is a big bet for both medicine and regenerative dentistry. Treatments with this therapy can offer more quality of life for people. The potential of these very special cells lies in two peculiar characteristics: they are able to multiply and differentiate into other types of cells, such as tissues, cartilage and neurons. It is in this way that they play a key role for studies and treatments related to regeneration. The use of stem cells in dentistry makes possible different dental processes that offer more quality of life to the patient. That's because factors such as genetic defects, harmful habits, tooth decay, and early tooth loss all contribute to lifelong tooth loss. At the beginning of the twenty-first century, around the years 2005, 2006, researchers began to publish in international journals of the area a new technique based on the use of existing stem cells in the supporting bone of the teeth and in the alveolar tooth joint. This technique, called Revascularization, promotes the appearance of a new healthy pulp tissue, returning to the tooth its vitality and hygiene(AU)

Effect of low concentration of sodium fluoride on osteogenic/odontogenic differentiation of human dental pulp cells / 口腔疾病防治

Objective@#To study the effect of low concentrations of sodium fluoride on the osteogenic/odontogenic differentiation of human dental pulp cells (hDPCs) in vitro.@*Methods@#This study was reviewed and approved by the Ethics Committee. hDPCs were cultured using a modified tissue explant technique in vitro. The effects of different concentrations of sodium fluoride on the proliferation of hDPCs were measured by methylthiazol tetrazolium (MTT) assay. Appropriate concentrations were added to the osteogenic/odontogenic differentiation induction medium, and the cells were induced in vitro. Alizarin red S staining was used to detect the osteoblastic/odontogenic differentiation ability of the cells, and the mRNA expression of the key differentiation factors was detected by RT-qPCR. Moreover, the expression of key molecules of endoplasmic reticulum stress (ERS) was detected by RT-qPCR and Western blot. The data were analyzed with the SPSS 18.0 software package.@*Results@#Low concentration of NaF (0.1 mmol/L) could stimulate cell proliferation in vitro, while a high concentration (5-10 mmol/L) could inhibit cell proliferation (P<0.05). According to the literature and the experimental data, 0.1 mmol/L NaF was selected as the following experimental concentration. The levels of alizarin red S staining were increased after NaF induction of mixed osteogenic/odontogenic differentiation in vitro. The mRNA expression levels of key molecules for osteogenic/odontogenic differentiation, dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP) and osteocalcin (OCN), were increased (P<0.05). The mRNA levels of ERS markers (splicing x-box binding protein-1 (sXBP1), glucose-regulated protein 78 (GRP78) and activating transcription Factor 4 (ATF4) were increased in NaF-treated cells. The protein expression levels of key ER stress molecules (phosphorylated RNA-activated protein kinase-like ER-resident kinase (p-PERK), phosphorylated eukaryotic initiation factor-2α (p-eIF2α) and ATF4) were higher in NaF-treated cells.@*Conclusion@#A low concentration of NaF promotes the osteogenic/odontogenic differentiation of hDPCs and increases the level of ER stress.

Epidermoid cyst in the right mandible: a case report and literature review / 口腔疾病防治

Objective@#To discuss the possible etiology, pathogenesis, clinical features, diagnosis and treatment of epidermoid cysts of the jaw and to provide a reference for clinical diagnosis and treatment.@*Methods@#A case of an epidermoid cyst in the right mandible with retained deciduous teeth and succedaneous impacted teeth was reviewed and analyzed in combination with the relevant literature.@*Results@#A patient presented with a mass in the right mandible that had persisted for 1 month after being found at imaging examination. Tooth 83 was retained, and tooth 43 was unerupted. Swelling was characterized by no obvious tenderness, fluctuation, or table tennis sensation and was observed in the lingual alveoli of teeth 83, 44, and 45. Imaging revealed a low-density shadow in the apex of teeth 83, 44, 45, and 46, approximately 1.9 cm × 2.6 cm × 1.6 cm in size, which wrapped around the dental crown of tooth 43. Preliminary diagnoses were as follows: right mandibular mass thought to be a dentigerous cyst; impacted tooth 43; and retained primary tooth 83. The mass in the right mandible was removed, and teeth 43 and 83 were extracted under intravenous and inhalation anesthesia. During the operation, the mass was observed to have a thin cyst wall and contained bean-like residue. Histopathological examination indicated an epidermoid cyst in the right mandible. At the 1-week follow-up examination, the patient reported no discomfort, and the surgical area showed good recovery. According to the literature, epidermoid cysts are benign cysts originating from ectopic ectodermal tissue that can occur throughout the body but rarely in the oral cavity and are even extremely rarer in the jaw. Epidermoid cysts of the jaw, which have no specific clinical manifestations, can be confused with odontogenic cysts such as dentigerous cysts and odontogenic tumors. Dental pulp tests and other techniques can serve as a reference for clinicians. The diagnosis is confirmed via histopathology. Surgical removal is a common treatment, with a good prognosis and a low recurrence rate.@*Conclusion@#The principle of treatment for an epidermoid cyst of the jaw is similar to that for a jaw cyst. The prognosis is good when the cyst is removed completely.

Mechanism of Chir99021 regulating Wnt / β⁃catenin signaling pathway inhibiting osteogenic differentiation of rat dental pulp stem cells / 解剖学报

Objective To explore the effect and mechanism of Chir99021 on osteogenic differentiation of rat dental pulp stem cells. Methods Primary rat dental pulp stem cells were isolated from rat dental pulp and verified by fluorescence immunoassay. Different concentrations of Chir99021 were set, and the cell proliferation was detected by CCK⁃8 to select the optimal concentration. Osteogenic differentiation was detected by alizarin red staining. The expression of osteogenic differentiation related genes and proteins recombinant wingless type MMTV integration site famity member 1 (Wnt1), Wnt3a and Wnt3a β⁃expression of catenin, axis inhibition protein 2(Axin 2), dentin sialophosphoprotein(OCN) and dentin matrix acidic phosphoprotein 1(DMP1) was detected by Real⁃time PCR and Western blotting. Results The positive expression of dentin sialophosphoprotein (DSPP) and vimentin indicated that rat dental pulp stem cells were successfully isolated. After osteogenic induction of rat dental pulp stem cells, calcium deposits significantly increased with the addition of glycogen synthase kinase⁃3β(GSK⁃3β) inhibitor Chir99021, calcium deposits were significanted reduced. After osteogenic differentiation of rat dental pulp stem cells, the expression of Wnt1, Wnt3a, β⁃catenin, Axin2, OCN and DMP1 increased, while the expression of Wnt1, Axin2, OCN and DMP1 decreased with the addition of Chir99021. Conclusion Chir99021 can inhibit the osteogenic differentiation of rat dental pulp stem cells after 7 days of induction.

Dental age estimation by assessing the pulp volume of five teeth in a peruvian population using cone beam computed tomography images / Estimación de la edad dental evaluando el volumen pulpar de cinco dientes utilizando imágenes de tomografías computarizadas de haz cónico en una población peruana

Abstract Dental age estimation is very important for individual identification in criminal and civil forensic investigations. One of the methods for age estimation is studying age related changes in pulp volume of teeth. The objective of the current study was to estimate dental age from the pulp volume of five different categories of teeth of a Peruvian sample using cone beam computed tomography (CBCT). Retrospective CBCT records of 231 patients (females (134), males (97), age: 12-60 years) were included in the study, categorized into five different age groups (12-19, 20-29, 30-39, 40-49, 50-59, 60 years and older). Dental pulp volume of five categories of teeth(upper canines, left upper central incisors, left upper first molars, lower left first premolars, first molars) were analyzed using Romexis® 5.3.3.5 software for each patient. There was a reduction in the pulp volume of upper right and left canine with age. The Pulp volume was lowest in people aged 60 years and over. Linear regression analysis of the pulp volume and chronological age showed a coefficient of determination of 30%, suggesting a weak correlation. A weak correlation between dental pulp and age is derived. But, a robust large homogenous sample of teeth in future for different age groups may establish a reliable regression equation.

Resumen La estimación de la edad dental en personas vivas y cadáveres es muy importante para la Odontología Forense, sobre todo en casos de identificación en investigaciones legales y sociales. El objetivo del estudio fue estimación de la edad dental mediante la medición del volumen pulpar de imágenes dentales en tomografía computarizada de haz cónico (TCHC) de pacientes peruanos. Fueron analizadas 231 TCHC de pacientes entre 12 a 60 años a más. (Mujeres (134), hombres (97)) se dividieron en seis grupos de edad (12-19, 20-29, 30-39, 40-49, 50-59, 60 años a más). El análisis volumétrico de la pulpa dental se realizó en un total de 1155 dientes (caninos superiores, incisivos centrales superiores izquierdos, primeros molares superiores izquierdos y primeros premolares inferiores izquierdos), mediante el software Romexis® 5.3.3.5. El análisis de regresión lineal mostró un coeficiente de determinación del 30% que sugiere una correlación débil entre la relación del volumen pulpar de los dientes y la edad. El volumen pulpar de los caninos superiores derecho e izquierdo disminuyó a medida que aumentaba la edad y el volumen pulpar en dientes de personas de 60 años a más fue el más bajo. Sin embargo, se pueden proponer estudios futuros para incluir una gran muestra homogénea de dientes en diferentes categorías y grupos de edad para confirmar la correlación y establecer una ecuación de regresión confiable.

Continuous Wave of Condensation Improves the Filling of Curved Canals: a Micro-CT Study / La condensación de onda contínua mejora el selle de canales curvos: un estudio de micro-CT

Abstract The aim of this study was to compare the filling capacity in curved root canal using a new continuous wave of condensation technique (Termo Pack II, Easy Dental Equipments, Brazil) or lateral compaction. The percentage of voids in the filling of mesial root canals of mandibular molars was assessed by micro-computed tomography (micro-CT). Mesial root canals (n=24) of mandibular molars with a degree of curvature between 20° and 40° were prepared using rotary system (ProDesign Logic, Easy, Brazil) up to #35, .05 taper. The root canals were filled by using the continuous wave of condensation system or lateral compaction and AH Plus sealer (n=12). Scanning at 9 µm was performed after preparation and after filling by using micro-CT SkyScan 1176. The volumetric percentage of filling material and voids (total length and in each root canal third) were calculated. Data were analyzed using ANOVA/ Tukey and Student's t tests (α=0.05). Before the filling techniques, the root canals volume after preparation was similar (p>0.05). The root canals filled by the continuous wave of condensation technique presented the lowest percentage of voids, and the greatest percentage of filling material in total length and thirds (cervical, middle and apical) (p<0.05). Both techniques were not able of completely filling the root canals. The continuous wave of condensation technique Termo Pack II promoted better root canal filling in curved root canals, when compared with lateral compaction.

Resumen El objetivo de este estudio fue comparar la capacidad de obturación en conductos radiculares curvos utilizando una nueva técnica de condensación de onda continua (Termo Pack II, Easy Dental Equipments, Brasil) vs compactación lateral. El porcentaje de brechas en la obturación de los conductos radiculares mesiales de los molares mandibulares se evaluó mediante microtomografía computarizada (micro-CT). Se prepararon conductos radiculares mesiales (n=24) de molares mandibulares con un grado de curvatura entre 20° y 40° utilizando un sistema rotatorio (ProDesign Logic, Easy, Brasil) al #35, conicidad 0,05. Los conductos radiculares se obturaron utilizando un sistema de condensación de onda contínua o compactación lateral y cemento AH Plus (n=12). Se realizó un escaneo de 9 µm después de la preparación y después de la obturación usando el micro-CT SkyScan 1176. Se calculó el porcentaje volumétrico de material de obturación y vacíos (longitud total y en cada tercio del conducto radicular). Los datos se analizaron utilizando las pruebas ANOVA/Tukey y t de Student (α=0,05). Antes de las técnicas de obturación, el volumen de los conductos radiculares después de la preparación fue similar (p>0,05). Los conductos radiculares obturados con la técnica de condensación por onda contínua presentaron el menor porcentaje de vacíos y el mayor porcentaje de material de obturación en longitud total y en tercios (cervical, medio y apical) (p<0,05). Ambas técnicas no fueron capaces de llenar completamente los conductos radiculares. La técnica de condensación de onda contínua Termo Pack II promovió un mejor relleno del conducto radicular en conductos radiculares curvos en comparación con la compactación lateral.

Effect of voxel size of Micro-CT on the assessment of root canal preparation

The aim of this study was to assess the influence of micro-computed tomography (micro-CT) voxel size on evaluation of root canal preparation using rotary heat-treated nickel-titanium files. Curved mesial root canals of mandibular molars were prepared using ProDesign Logic 30/.05 (PDL) or HyFlex EDM 25/.08 (HEDM) (n=12). The specimens were scanned using micro-CT with 5μm of voxel size before and after root canal preparation. Images with sub-resolution of 10 and 20μm voxel sizes were obtained. The percentage of volume increase, debris and uninstrumented root canal surface were analyzed in the different voxel sizes. Data were compared using unpaired Student's t-test and ANOVA statistical tests (α=0.05). No differences were observed for percentage of volume increase, debris and instrumented surface between the root canals prepared by PDL and HEDM (p>0.05). Both systems promoted higher percentage of debris in the apical third compared to the middle third (p0.05). PDL and HEDM had similar root canal preparation capacity. Micro-CT images using different voxel sizes did not influence the results of volume increase and debris evaluation. However, images at 5µm showed greater accuracy to evaluate the percentage of uninstrumented surfaces.

El objetivo de este estudio fue evaluar la influencia del tamaño de vóxel de la microtomografía computarizada (micro-CT) en la evaluación de la preparación del conducto radicular utilizando limas rotatorias de níquel-titanio tratadas térmicamente. Se prepararon conductos radiculares mesiales curvos de molares mandibulares usando ProDesign Logic 30/.05 (PDL) o HyFlex EDM 25/.08 (HEDM) (n=12). Las muestras se escanearon usando micro-CT con un tamaño de vóxel de 5μm antes y después de la preparación del conducto radicular. Se obtuvieron imágenes con subresolución de vóxeles de 10 y 20μm. Se analizó el porcentaje de aumento de volumen, residuos y superficie del conducto radicular no instrumentado en diferentes tamaños de vóxel. Los datos se compararon usando la prueba t de Student no pareada y las pruebas estadísticas ANOVA (α=0,05). No se observaron diferencias en el porcentaje de aumento de volumen, detritus y superficie instrumentada entre los conductos radiculares preparados por PDL y HEDM (p>0,05). Ambos sistemas promovieron un mayor porcentaje de detritos en el tercio apical en comparación con el tercio medio (p0,05). PDL y HEDM tenían una capacidad de preparación del conducto radicular similar. Las imágenes de micro-CT que utilizan diferentes tamaños de vóxel no influyeron en los resultados de la evaluación del volumen y los desechos. Sin embargo, las imágenes de 5µm mostraron una mayor precisión al evaluar el porcentaje de superficies no instrumentadas.

Tratamento de lesão periradicular, de origem endodôntica, com auxílio de laserterapia: uma revisão sistemática da literatura e apresentação se caso clínico / Treatment of periradicular injury, of endodontic origin, with the aid of laser therapy: a systematic review of the literature and presentation if clinical case

É sabido que a cavidade oral é a porta de entrada para muitos microrganismos e que possui alguns gêneros de bactérias que quando se associam ou proliferam em excesso, com a falta de higienização correta, fatores ambientais e imunológicos podem causar danos em algumas partes dos dentes como no tecido pulpar e canais radiculares. Neste sentido, a endodontia tem sido capaz de tratar pessoas com problemas dentários em fases muito precoces como as medidas profiláticas até casos infeciosos que afetam a polpa dos dentes causando as lesões perirradiculares que são infecções causadas por microrganismos, Para tanto, é necessário que a odontologia ofereça transformações positivas por meio de técnicas que sejam mais previsíveis para os tratamentos. A literatura tem indicado o uso da laserterapia como técnica auxiliar para o tratamento endodôntico pelo seu potencial mínimo invasivo, preciso e eficaz em menor tempo de cura de patologias orais como as lesões perirradiculares. Este estudo pretendeu abordar a importância da laserterapia sobre as variáveis patológicas de pacientes com lesão perirradiculares. Para realiza-lo foi necessário buscar na literatura estudos que associem este tipo de tratamento e sua eficiência no tratamento desta patologia. Para realizar esta pesquisa foi necessário buscar dados na literatura que tratam sobre o tema para investigar o tempo indicado ao tratamento com a laserterapia bem como o estágio em que as lesões podem ser tratadas com auxílio deste método. Corroborando com o estudo apresentamos um caso clínico(AU)

It is known that the oral cavity is the gateway to many microorganisms and that it has some genera of bacteria that when they associate or proliferate in excess, with the lack of correct hygiene, environmental and immunological factors can cause damage in some parts of the teeth such as in pulp tissue and root canals. In this sense, endodontics has been able to treat people with dental problems at very early stages such as prophylactic measures to infectious cases that affect the pulp of teeth causing perirradicular lesions that are infections caused by microorganisms, therefore, it is necessary that dentistry offer positive transformations through techniques that are more predictable for treatments. The literature has indicated the use of laser therapy as an auxiliary technique for endodontic treatment for its minimal invasive, precise and effective potential in shorter time of cure of oral pathologies such as perirradicular lesions. This study aimed to address the importance of laser therapy on the pathological variables of patients with perirradicular lesions. To accomplish this, it was necessary to seek studies in the literature that associate this type of treatment and its efficiency in the treatment of this pathology. To carry out this research it was necessary to seek data in the literature that deal with the subject to investigate the time indicated for treatment with laser therapy as well as the stage at which lesions can be treated with the aid of this method. Corroborating the study, we present a clinical case(AU)

Pulpectomia o pulpotomía en el tratamiento de dientes temporales: Revisión

Objetivo: Comparar las terapias pulpares de dientes temporales en pacientes según la evidencia en la literatura. Metodología: Revisión bibliográfica en la literatura científica, en las siguientes bases de datos: PUBMED, MEDLINE, BVS, BBO Odontología, IBECS y Web of Science. Los descriptores seleccionados fueron: pulpotomía y pulpectomia, combinados en la siguiente estrategia de búsqueda: (pulpotomía) AND (pulpectomía). Resultados: Se encontraron 65 artículos, seleccionados por título y resumen. Después de una lectura minuciosa, solamente 23 artículos cumplieron con el criterio de inclusión que fuera un ensayo clínico, estudio longitudinal (cuasiexperimental o cohorte), no se excluyeron artículos duplicados y 13 que no tenían relación directa con el tema. La muestra final totalizó 7 artículos para la revisión integradora. La evidencia es limitada por el número de estudios que cumplieron con los criterios. Conclusiones: La contribución de este estudio sobre el tema es aumentar el conocimiento con respecto a las terapias pulpares; contribución que requiere ser mejorada o detallada en estudios posteriores; por tal motivo no se puede hacer una conclusión definitiva respecto a cuál de los tratamientos pulpares es mejor, pero nos indica una tendencia para desde el punto de vista clínico poder considerar los tratamientos pulpares como una alternativa adecuada para mantener el diente temporal en la cavidad bucal con evidencia científica.

Objective: To compare pulp therapy of primary teeth in patients according to the evidence in the literature. Methodology: Literature review in the scientific literature, in the following databases: PUBMED, MEDLINE, BVS, BBO Dentistry, IBECS and Web of Science. The descriptors selected were: pulpotomy and pulpectomy, combined in the following search strategy: (pulpotomy) AND (pulpectomy). Results: 65 articles were found by selecting by title and abstract. After a thorough reading only 23 articles met the inclusion criteria of being a clinical trial, longitudinal study (quasi-experimental or cohort), duplicate articles and 13 that were not directly related to the topic were not excluded. The final sample totaled 7 articles for the integrative review. The evidence is limited by the number of studies that met the criteria. Conclusions: The contribution made on the subject is to increase knowledge regarding pulp therapies, which needs to be improved or detailed in further studies, for that reason we cannot make a definitive conclusion on which of both pulp treatments is better, but it gives us a tendency and from a clinical point view to be able to consider pulp treatments as an adequate alternative to maintain the primary tooth in the oral cavity with scientific evidence.

Estimation of dental age using the kvaal method with digital panoramic radiographs in peruvian adults / Estimación de la edad dental según el método de Kvaal con radiografías panorámicas digitales en adultos peruanos

To determine the accuracy of the Kvaal method in the estimation of dental age through the analysis of digital panoramic radiographs of patients between 20 and 47 years of age who attended the stomatological clinic of the Universidad Científica del Sur, (2018 to 2019), Lima-Perú. 289 digital panoramic radiographs belonging to individuals of both sexes, aged 20 to 47 years were analyzed. Length and width measurements were obtained in the dental and pulp chamber in the upper central incisors. These data were subsequently evaluated by calculating the proportions between the pulp and root length of the upper central incisor by applying the formula of the method of Kvaal et al. to obtain the accuracy of the method in estimating dental age. Applying the formula of Kvaal et al. indicates that the relationship between the width of the pulp and the length of the root has a higher level of significance in relation to others proportions: M mean value of all ratios except T (-0.659) and W-L difference between W and L (-0.643). The coefficient of determination (r²) and standard error of estimation (SEE) using the original Kvaal formula is r²: 0.70, SEE: 4.90 years, then a modified Kvaal formula was proposed for the Peruvian population. The Method of Kvaal et al. has an accuracy of 1.24 in estimating the dental age of individuals, using the upper central incisor in digital panoramic radiographs.

Determinar la precisión del método de Kvaal en la estimación de la edad dental mediante el análisis de radiografías panorámicas digitales de pacientes entre 20 a 47 años atendidos en la clínica estomatológica de la Universidad Científica del Sur, (2018 a 2019), Lima-Perú. Se analizaron 289 radiografías panorámicas digitales pertenecientes a individuos de ambos sexos, de 20 a 47 años. Se obtuvo medidas de longitud y anchura en la cámara dental y pulpar en los incisivos centrales superiores. Estos datos se valoraron posteriormente al calcular las proporciones entre la pulpa y longitud de la raíz del incisivo central superior aplicando la fórmula del método de Kvaal et al. para obtener la precisión del método en la estimación de la edad dental. Al aplicar la fórmula de Kvaal et al. indica que la relación entre la anchura de pulpa y la longitud de la raíz presentan un nivel de significancia mayor en relación a otras proporciones: M valor medio de todas las proporciones excepto T (-0.659) y W-L: diferencia entre los valores de W y L (-0.643). El coeficiente de determinación (r²) y el error estándar de la estimación (SEE) utilizando la fórmula original de Kvaal es de r²: 0.70, SEE: 4.90 años, después se propuso una fórmula modificada de Kvaal para la población peruana. El Método de Kvaal et al. tiene una precisión del 1.24 en la estimación de la edad dental de los individuos, utilizando el incisivo central superior en radiografías panorámicas digitales.

Endodontia guiada: tecnologia aplicada na resolução de tratamentos de canais calcificados / Guided endodontics: technology applied in the resolution of treatments of calcified canals / Endodoncia guiada: tecnología aplicada en la resolución de tratamientos de conductos calcificados

As calcificações pulpares provocam alterações morfológicas no interior dos canais radiculares que dificultam o tratamento endodôntico. Para solucionar essa dificuldade, a ferramenta Endoguide ou Endodontia Guiada foi desenvolvida para a resolução de casos complexos. Esta pesquisa objetivou descrever as aplicações da ferramenta Endoguide no tratamento de canais calcificados na endodontia. Todas as buscas foram realizadas por um único pesquisador na base de dados PubMed/MEDLINE e busca manual utilizando os descritores "Endodontics", "Digital", "Cone beam", "Guided". Foram considerados elegíveis os artigos publicados entre 2010 e 2022 e excluídos os estudos cuja publicação não foi obtida na íntegra e ainda aqueles em que os resultados não apresentaram embasamento teórico e prático suficientes para que pudessem ser incluídos no trabalho. Após as buscas, foram encontrados 47 artigos, selecionados inicialmente pelo título e resumos, excluindo as duplicatas. Ao final, a leitura completa e coleta de dados foi realizada em 6 artigos. As informações relevantes dos artigos selecionados foram transcritas em forma de quadro para sumarizar os achados. A endodontia guiada pode ser uma excelente alternativa para tratamentos de casos complexos, necessitando um investimento financeiro mínimo no consultório, pois os equipamentos de captura de imagem, planejamento virtual e de guias podem ser realizados em laboratórios capacitados. Assim, concluímos que o emprego da Endoguide como ferramenta no tratamento de canais calcificados se mostrou bem-sucedido e sua utilização não requer um conhecimento amplo, podendo ser usada por profissionais menos experientes.

Pulp calcifications cause morphological changes inside the root canals that make endodontic treatment difficult. To solve this difficulty, the tool Endoguide or Guided Endodontics was developed to solve complex cases. This research aimed to describe the applications of the Endoguide tool in the treatment of calcified root canals in endodontics. All searches were performed by a single researcher in the PubMed/MEDLINE database and manual search using the descriptors "Endodontics", "Digital", "Cone beam", "Guided". Articles published between 2010 and 2022 were considered eligible, and studies whose publication was not obtained in full text were excluded, as well as those in which the results did not have sufficient theoretical and practical basis for them to be included in the study. After the searches, 47 articles were found, initially selected by title and abstract, excluding duplicates. In the end, the complete reading and data collection was performed with 6 articles. Relevant information from the selected articles was transcribed for a table to summarize the findings. Guided endodontics can be an excellent alternative for treating complex cases, requiring minimal financial investment in the office, as image capture equipment, virtual planning and guides can be performed in trained laboratories. Thus, we conclude that the use of Endoguide as a tool in the treatment of calcified canals proved to be successful and its use does not require extensive knowledge and can be used by less experienced professionals.

Las calcificaciones pulpares provocan cambios morfológicos en el interior de los conductos radiculares que dificultan el tratamiento endodóntico. Para solventar esta dificultad se desarrolló la herramienta Endoguide o Endodoncia Guiada para resolver casos complejos. El objetivo de esta investigación fue describir las aplicaciones de la herramienta Endoguide en el tratamiento de conductos radiculares calcificados en endodoncia. Todas las búsquedas fueron realizadas por un único investigador en la base de datos PubMed/MEDLINE y búsqueda manual utilizando los descriptores "Endodontics", "Digital", "Cone beam", "Guided". Se consideraron elegibles los artículos publicados entre 2010 y 2022, y se excluyeron los estudios cuya publicación no se obtuvo a texto completo, así como aquellos en los que los resultados no tenían suficiente base teórica y práctica para ser incluidos en el estudio. Tras las búsquedas, se encontraron 47 artículos, seleccionados inicialmente por título y resumen, excluyendo los duplicados. Al final, se realizó la lectura completa y la recogida de datos con 6 artículos. La información relevante de los artículos seleccionados se transcribió para elaborar una tabla que resumiera los hallazgos. La endodoncia guiada puede ser una excelente alternativa para el tratamiento de casos complejos, requiriendo una mínima inversión financiera en el consultorio, ya que los equipos de captura de imágenes, la planificación virtual y las guías pueden realizarse en laboratorios capacitados. Así, concluimos que el uso de la Endoguía como herramienta en el tratamiento de conductos calcificados demostró ser exitoso y su uso no requiere de grandes conocimientos y puede ser utilizado por profesionales menos experimentados.

Protocolo para diafanización dental / Protocol for dental diafanization

Antecedentes: La Diafanización dental es una técnica que permite transparentar los dientes haciendo visible la anatomía interna de los conductos radiculares ofreciendo una herramienta pedagógica económica y confiable; sin embargo, la literatura no reporta protocolos estandarizados para obtener una diafanización dental predecible. Objetivo: Obtener un protocolo estandarizado para diafanización dental, como modelo educativo, a partir de la revisión de la literatura y la realización de un estudio piloto. Materiales y Métodos: Se realizó una búsqueda sistemática en las bases de datos Scopus y Medline con los términos Mesh "root canal", "diaphonization", "clearing", "morphology" anatomy", y se estructuró una tabla de extracción con las variables más representativas para establecer las 3 fases de la Diafanización, a. Descalcificación, se evaluó Ácido Nítrico 5% (HNO3), Ácido Fórmico 10% (CH2O2) y EDTA 10%, b. Deshidratación, se empleó Alcoholes etílicos ascendentes, c. Clarificación, se evaluó Metil Salicilato y Aceite de Inmersión Sintético. Se seleccionaron 54 dientes, 36 sin endodoncia, y 18 con endodoncia, y se distribuyeron en dos grupos: Grupo A. Dientes sin endodoncia, Grupo B. Dientes con endodoncia, constituidos por 18 subgrupos que estaban definidos de acuerdo al tipo de descalcificante, momento de aplicación medio de contraste y medio de Clarificación. Resultados: El Ácido Nítrico al 5% pese a que fue el más corrosivo, permitió el mayor flujo y accesibilidad para el medio de contraste (Tinta China) en especímenes sin endodoncia. De igual manera, el Ácido Fórmico al 10%, preservó la estructura de los dientes tratados endodónticamente. El Metil Salicilato como clarificante, brindó mejores resultados visuales alcanzando una mayor transparencia. Conclusiones: El desarrollo de un estudio piloto para estandarizar técnicas de diafanización en odontología, permite la estructuración de un protocolo educativo que posibilita conocer la gran variabilidad anatómica de los dientes y la comprensión y análisis de los dientes que han si do tratados endodóncicamente, aportando una herramienta pedagógica para la comprensión de la anatomía radicular. El uso de Ácido Fórmico al 10%, en dientes con tratamiento de endodoncia y de Ácido Nítrico 5% en dientes sin endodoncia, c on una transparencia alcanzada por el uso del Metil Salicilato, muestran los mejores resultados visuales en anatomía y obturación endodóntica.

Background: Dental diaphonization is a technique that allows the teeth to be made transparent, making the internal anatomy of the root canals visible, offering an economical and reliable pedagogical tool; however,the literature does not report standardized protocols to obtain a predictable dental clearance. Aim: obtain a standardized protocol for dental diaphonization as an educative model from the review of the literature and the realization of a pilot study. Materials and methods: A systematic search was made on databases Scopus and Medline, with the Mesh terms "root canal", "diaphonization", "clearing", "morphology" and, "anatomy", and an extraction table was structured wit h the most representative variables to establish the three diaphanization phases, a. Decalcification, 5% Nitric Acid, 10% Formic Acid (TBD-2) and 10% EDTA were evaluated, b. Dehydration, ascending Ethyl Alcohols were used, c. Clarification, Methyl Salicylate, a nd Immersion synthetic oil were evaluated. 54 teeth were selected, 36 without root canal treatment and 18 with root canal treatment, then they were distributed into two groups: Group A, Teeth without root canal treatment, and Group B, Teeth with root canal treatment. Each group was constituted of 18 subgroups defined in order of the decalcification agent type, moment of the contrast medium application, and clarification agent type. Results: Even though 5% Nitric Acid was the most corrosive agent, it allowed a better flow and accessibility for the contrast medium (Chinese ink) in teeth without root canal treatment. Likewise, 10% Formic Acid preserved the structure of the endodontic tooth. As a clarification agent, the Methyl Salicylate showed better visual results, achieving greater transparency. Conclusion: The development of a pilot study aimed to standardize diaphonization techniques in dentistry allows the structuring of educative protocols that permit knowing the great tooth anatomic variability and the comprehension as well as the analysis of the root canal treated teeth, contributing to a pedagogic tool for the root anatomy awareness. Using 10% Formic Acid on root canal-treated teeth and 5% Nitric Acid on root canal not treated teeth, with transparency achieved by using Methyl Salicylate, showed better visual results on anatomy and endodontic filling

MiR⁃31 Promotes the Proliferation and Migration of Human Dental Pulp Mesenchymal Stem Cells / 中国生物化学与分子生物学报

Pulpitis and periapical inflammation are two common diseases in stomatology today. Existing treatment options primarily include root canal therapy and pulp revascularization, which can effectively control inflammation and preserve the affected tooth while also causing permanent deactivation of the pulp tissue, structural failure, and secondary infection. In recent years, research on dental pulp regeneration has progressively entered the public consciousness because of tissue engineering technology that combines stem cells and biomaterials. Due to their multi⁃differentiation and high proliferation, dental pulp stem cells (DPSCs) isolated from permanent or deciduous teeth have emerged as a significant stem cell source for dentin or pulp tissue regeneration. However, the number and survival time of live cells in the dam⁃ aged area are impacted, which significantly limits the efficacy of stem cells since they are unable to efficiently be recruited to the injured area. The ability of DPSCs to migrate and multiply must therefore be enhanced. This study sought to determine if miR⁃31 (miR⁃31) may significantly enhance the proliferative and migratory capacities of DPSCs. The tissue block enzyme digestion method was used to successfully separate and culture DPSCs from dental pulp tissues, and the miR⁃31 levels in dental pulp tissues and DPSCs from normal and inflammatory teeth were compared. The results of real⁃time fluorescence quanti⁃ tative PCR (RT⁃qPCR) revealed that the expression level of miR⁃31 in dental pulp tissues and DPSCs from inflammatory teeth was significantly lower when compared to the control group (P<0. 05). Interfer⁃ ence and over⁃expression of miR⁃31 expressions in DPSCs were specifically divided into three groups: the NC group, the miR⁃31 agomir (over⁃expressed) group and the miR⁃31 antagomir (inhibitor) group. RTq⁃PCR results showed that the transfection was successful (P<0. 001). The results of CCK⁃8, wound⁃ healing, and Transwell migration experiments showed that overexpression of miR⁃31 successfully improved the proliferation and migration abilities of DPSCs compared with the control group (P<0. 05). Further⁃ more, Western blotting analysis revealed that miR⁃31 overexpression increased the expression of important migratory proteins, including CXC chemokine receptor type 4 (CXCR4) and matrix metalloproteinase2 (MMP2), as well as key proliferation proteins Ki67 and proliferating cell nuclear antigen (PCNA) (P< 0. 05). This study demonstrates that miR⁃31 can effectively boost the proliferation and migratory ability of DPSCs, providing strong theoretical support for the increased use of DPSCs in regenerative medicine.

Research progress on in vivo models for stem cell-based pulp regeneration / 口腔疾病防治

@#Basic research on pulp regeneration requires in vivo experiments. The PubMed database was searched for in vivo models of stem cell-based pulp regeneration using the following keywords: "pulp regeneration", "stem cell" and "animal model". The retrieved models were classified into ectopic, semiorthotopic and orthotopic regeneration models and their characteristics and clinical values were reviewed. This literature review indicated that the ectopic regeneration model is the most widely used model for the simple steps. However, this model does not accurately capture clinical situations. The semiorthotopic regeneration model, which is an improvement of the ectopic regeneration model, can create a more realistic regeneration environment. The orthotopic regeneration model can simulate clinical procedures that more closely resemble application, but it is less commonly used for difficult operations and long experimental periods. The applicability of the above three animal models depend on the stage of the animal experiment: the ectopic regeneration model is suitable to test the regenerative effect and biocompatibility of the implant complex; the semiorthotopic regeneration model is suitable to more persuasively evaluate the regeneration effect of the implant complex; and the orthotopic regeneration model is suitable to confirm the regeneration effect and practicability of the regenerative implant complex prior to clinical study.

Progress on the cell therapy strategy of mesenchymal stem cells / 口腔疾病防治

@#Cell therapy based on mesenchymal stem cells (MSCs) has been a hot research topic in recent years, including the traditional cell therapy strategy based on living cells and the new cell-free therapy strategy based on soluble proteins or bioactive molecules such as extracellular vesicles (EVs). At present, MSC-induced cells have mature functions and specific structures, and insitu transplantation combined with biomaterials or organic technology has greatly improved the settlement rate and function. On the other hand, as the large-scale culture technique and EVs separation technique evolve, it is possible to obtain a large number of pure EVs, and EVs are gradually becoming a hot spot of current research. An increasing number of studies have shown that the therapeutic effect of MSCs not only occurs by implantation and differentiation but also manifests as the paracrine effect of MSCs. In this review, we discuss the emerging outcomes of cell therapies and acellular therapies to alleviate these pathological conditions.

Effect of stem cell factor on the angiogenic ability of cocultured DPSCs and HUVECs / 口腔疾病防治

Objective@#To study the effect of stem cell factor (SCF) on the angiogenic ability of cocultured dental pulp stem cells (DPSCs) and human umbilical vein endothelial cells (HUVECs).@*Methods @#This study has been reviewed and approved by the Ethics Committee. The experiment was split into the HUVECs, SCF+HUVECs, DPSCs+HUVECs, and SCF+DPSCs+HUVECs groups. A mixture of SCF and culture medium was used to prepare a mixed culture medium with an SCF concentration of 100 ng/mL. In vitro coculture of DPSCs and HUVECs was performed at a 1∶5 ratio. CCK-8 proliferation assay was used to observe the proliferative capacity of cells in each group on days 1, 3, 5, and 7. Wound healing and Transwell migration assays were used to detect the effect of SCF on cell migration under either direct or indirect coculture conditions, respectively. In vitro angiogenesis experiments were performed to detect the angiogenic capacity of the cells in each group. The vascular endothelial growth factor A (VEGFA) concentration in the cell culture supernatant was detected using ELISAs, and the protein expression levels of CD31, CD34, and VEGFA were detected using Western blot analysis. @*Results @# Wound healing and Transwell migration experiments showed that SCF significantly promoted the migration of cocultured DPSCs and HUVECs (P<0.05). The in vitro angiogenesis experiment showed that the number of branches and the total length of branches of tubular structures in the SCF+DPSCs+HUVECs group were significantly greater than those of the other groups (P<0.05), and the expression levels of the vascular-related proteins CD31, CD34, and VEGFA in this group were greater (P<0.01). @*Conclusion @# SCF can enhance the migration and in vitro angiogenesis of cocultured DPSCs and HUVECs.

LED red light up-regulates MAPK signal to promote osteogenic/odontogenic differentiation of human dental pulp stem cells in an inflammatory environment / 口腔疾病防治

Objective @#To study the effect of light-emitting diode (LED) red light on the osteogenic/odontogenic differentiation of human dental pulp stem cells (hDPSCs) and its mechanism were discussed. @*Methods@#This study has been reviewed and approved by the Ethics Committee. hDPSCs were cultured by tissue block enzyme digestion. The proliferative capacity of hDPSCs was detected by the CCK-8 at days 1, 3, 5 and 7 under stimulation with 0, 1, 5 and 10 μg/mL lipopolysaccharide (LPS), and the LPS stimulatory concentration was screened. The CG group (mineralization induction), LPS+CG group, and LPS+CG+ (2, 4, 6, 8, and 10 J/cm2) LED red light groups were set. On day 7, alkaline phosphatase (ALP) staining and ALP activity were determined. Relative expression levels of the ALP, osterix (OSX), dentin matrix protein-1 (DMP-1) and dentin sialophosphoprotein (DSPP) genes were measured by qRT-PCR. On day 21, alizarin red staining and calcium nodule quantitative determination were performed to screen the best light energy. The LPS+CG group and LPS+CG+LED group (optimal energy) were set up, and the secretion and expression levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were detected by ELISAs on days 1, 3, 5 and 7. The relative expression levels of the extracellular regulated protein kinases 1/2 (ERK1/2), p38, c-Jun N-terminal kinase (JNK), and extracellular regulated protein kinases 5 (ERK5) proteins and their phosphorylated proteins in the MAPK signaling pathway were detected by Western blots. After the pathway was blocked, the relative expression levels of the ALP, OSX, DMP-1, and DSPP proteins after LED red light irradiation on day 7 were detected by Western blots.@*Results@# CCK-8 assays showed that the proliferation of hDPSCs induced by 10 μg/mL LPS was lower than that of the 0, 1, and 5 μg/mL groups on the 5th and 7th days (P<0.05), and 10 μg/mL was selected as the LPS stimulatory concentration in the follow-up experiment. ALP staining, ALP activity, gene expression levels of ALP, OSX, DMP-1 and DSPP and calcium nodule quantification in the LPS+CG+4 J/cm2 group were higher than those in the other treatment groups (P<0.05). 4 J/cm2 LED red light had the strongest ability to promote osteogenic/odontogenic differentiation and was used as the LED light energy density in subsequent experiments. ELISA showed that the secretion and expression levels of TNF-α and IL-1β in the LPS+CG+LED group were lower than those in the LPS+CG group on the 5th and 7th days (P<0.05). Western blot analysis showed that 4 J/cm2 LED red light promoted the expression levels of the p-ERK1/2, p-p38, p-JNK and p-ERK5 proteins. After the MAPK pathway was blocked, the expression levels of the ALP, OSX, DMP-1, and DSPP proteins in the LPS+CG+LED+U0126 (ERK1/2 inhibitor), SP600125 (JNK inhibitor), and BIX02189 (ERK5 inhibitor) groups were lower than those in the LPS+CG+LED group (P<0.001). The protein expression levels of ALP, OSX and DMP-1 in the LPS+CG+LED+SB203580 (p38 inhibitor) group were not significantly different from those in the LPS+CG+LED group (P>0.05).@*Conclusion@#In inflammatory conditions, LED red light promotes osteogenic/odontogenic differentiation of hDPSCs. This effect may be attributed to enhancement of the ERK1/2, JNK, and ERK5 signaling pathways, which reduces the production of the inflammatory cytokines TNF-α and IL-1β.

Effect of angiopoietin 4 on odontogenic differentiation of dental pulp stem cells / 口腔疾病防治

Objective @# To investigate the effects of angiopoietin 4 (ANGPT4) on the odontogenic differentiation of human dental pulp stem cells. @* Methods @#This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. Human premolars were fixed, decalcified, dehydrated, embedded, and sectioned. Immunofluorescence staining was used to observe the expression and localization of ANGPT4. Human dental pulp stem cells (hDPSCs) were isolated and cultured in vitro. The growth state and morphology of hDPSCs were observed under an inverted phase contrast microscope. The expression of cell surface-related molecular markers was detected by flow cytometry. Alkaline phosphatase and alizarin red S staining were used to detect the odontogenic differentiation potential of hDPSCs. Oil-red O staining was used to detect the adipogenic differentiation potential of hDPSCs. RNA was extracted from hDPSCs at different time points after odontogenic induction, and RT-qPCR was used to analyze the mRNA expression of ANGPT4 and odontogenic-related genes during the odontogenic differentiation of hDPSCs in vitro. siRNA gene silencing technology was used to silence the expression of ANGPT4 in hDPSCs, and the silencing efficiency was detected by RT-qPCR and Western Blot. After silencing ANGPT4 in hDPSCs for 24 h, odontogenic induction was performed. Alkaline phosphatase and alizarin red S staining were performed on the 7th and 14th of induction to detect the odontogenic differentiation ability of hDPSCs after silencing ANGPT4@*Results @# Immunofluorescence staining of human premolars showed that ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone. hDPSCs were in good condition after 14 days of isolation and culture. Under the microscope, multiple cell colonies were observed, and the cell morphology was uniform and long spindle-shaped. The results of flow cytometry showed that hDPSCs expressed mesenchymal stem cell markers CD105 (90.42%) and CD90 (97.15%), but did not express hematopoietic cell markers CD45 (0.01%) and CD34 (0.08%). After odontogenic and adipogenic induction of hDPSCs, alkaline phosphatase staining, alizarin red S staining and oil red O staining were positive. The results of RT-qPCR after the odontogenic induction of hDPSCs showed that ANGPT4 was highly expressed on the 5th, 7th, 11th and 14th days of differentiation of hDPSCs (P<0.05), with the highest expression level on the 5th day. After hDPSCs were transfected with si-ANGPT4, the expression of ANGPT4 mRNA and protein was significantly down-regulated (P<0.05). The results of alkaline phosphatase staining showed that ALP staining intensity and area in the si-ANGPT4 group were significantly lower than those in the negative control. Alizarin red S staining showed that the formation of calcium nodules in the si-ANGPT4 group was significantly lower than that in the negative control.@* Conclusion@#ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone of human premolars. ANGPT4 may be a factor to promote the odontogenic differentiation of hDPSCs.

Advances in the study on cytokines related to dental pulp regeneration / 口腔医学

@#With the development of molecular biology, biomaterials and tissue engineering, regenerative treatment of pulpal and periradicular diseases is facing new opportunities. At present, a large number of studies on dental pulp regeneration reveal that cytokines are essential for promoting migration, proliferation and osteogenic differentiation of dental pulp stem cells. In this paper, we review several kinds of cytokines related to dental pulp regeneration, and analyze their roles and regulatory mechanisms in dental pulp regeneration.

Prognóstico pulpar após lesões por luxação em dentes permanentes: uma análise de riscos competitivos / A retrospective cohort study of pulp prognosis in luxated permanent teeth: a competing risk analysis

As lesões por luxação representam o grupo de lesões traumáticas dento-alveolares (LTDA) caracterizadas pelo dano simultâneo ao feixe vásculo-nervoso periapical e estruturas de sustentação dentária, em diferentes graus de complexidade, dependendo da força e direção do impacto. A patogenia das alterações pulpares decorrentes das luxações é resultado da extensão da lesão do feixe vásculo-nervoso apical e de sua capacidade de reparo, que determinam os seguintes desfechos para a polpa: manutenção da vitalidade pulpar, manutenção da vitalidade pulpar com obliteração da cavidade pulpar (OCP) ou a necrose pulpar. Entretanto, o processo de reparo pulpar pode envolver fenômenos intermediários cujos sinais e sintomas se modificam ao longo do período de acompanhamento até um diagnóstico definitivo. Sendo assim, do ponto de vista clinico, o tempo até a observação destas respostas, bem como seus fatores determinantes, representa uma informação tão importante quanto o próprio desfecho, pois tem influência direta na tomada de decisão sobre as condutas clinicas mais adequadas. A presente pesquisa consistiu num estudo clínico longitudinal retrospectivo com o objetivo de avaliar o prognóstico pulpar de dentes permanentes portadores de lesões por luxação, seu padrão cronológico e fatores determinantes, entre os pacientes atendidos na Clínica de Traumatismos Dentários da Faculdade de Odontologia da Universidade Federal de Minas Gerais no período de 2014 a 2022. Foram analisados prontuários de 224 pacientes com 427 dentes permanentes portadores de luxações, acompanhados por um período mediano de 1,4 anos (variação de 11 dias a 6,9 anos). O padrão de resposta pulpar foi classificado como manutenção da vitalidade pulpar, OCP e necrose pulpar através da avaliação clínica e radiográfica. Uma análise de sobrevivência utilizando-se o modelo de riscos competitivos foi realizada e curvas de função de incidência acumulada (FIA) foram construídas para se avaliar as taxas de cada um dos desfechos pulpares utilizando-se o estimador de Aalen-Johansen. O efeito de variáveis independentes, incluindo sexo, idade do paciente no momento do trauma, estágio de desenvolvimento radicular, grupo dentário, tipo de luxação, presença de fratura coronária concomitante e prescrição de antibioticoterapia sistêmica (ATS), foi avaliado utilizando-se um modelo multivariado de Cox causa-específico. Os dados foram analisados no programa estatístico R (versão 4.0.4, Viena, Áustria, 2021). Os resultados demonstraram manutenção da vitalidade pulpar em 38,2% da amostra (163 dentes), necrose pulpar em 28,1% (120 dentes) e OCP em 12,9% da amostra (55 dentes). O tempo mediano para o diagnóstico de necrose pulpar foi de 3 meses, enquanto o tempo para vitalidade pulpar foi de 8 meses e para OCP foi de 16 meses A probabilidade de manutenção de vitalidade pulpar diminuiu significativamente com a ocorrência de fraturas coronárias de esmalte e dentina concomitantes (HR 0,38 IC 95% [0,2 ­ 0,8] p = 0,006). A taxa de necrose pulpar foi significativamente menor em dentes com forame apical amplo (HR 0,62 IC 95% [0,4 ­ 0,96] p = 0,03) mas aumentou significativamente em dentes com luxações associadas às fraturas coronárias (HR 4,0 IC 95% [2,6 - 6,1] p = 0,001) e em dentes portadores de luxações intrusivas (HR 2,3 IC 95% [1,2 - 4,1] p = 0,007). Dentes portadores de luxações laterais ou extrusivas (HR 3,0 IC 95% [1,3 ­ 6,9] p = 0,001) ou com forame amplo (HR 2,4 IC 95% [1,2 ­ 4,7] p=0.01) apresentaram as maiores taxas de OCP.

Luxation injuries are a group of traumatic dental injuries (TDI) that involve damage to both the pulp and periodontium, with different degrees of complexity. Pulp damage results from injury to the apical neuro-vascular bundle and, depending on the repair potential, may result in the following outcomes: maintenance of pulp vitality, maintenance of pulp vitality with pulp canal obliteration (PCO) or pulp necrosis. However, the pulp healing process may involve intermediate and reversible phenomena whose signs and symptoms mimic pulp necrosis, rendering the timing of these events critical for decision-making during the follow-up period. The present study consisted in a retrospective cohort to evaluate the pulpal prognosis of luxated permanent teeth, its chronological pattern and predictive factors, among patients treated at the Dental Trauma Clinic of the Federal University of Minas Gerais, from 2014 to 2021. Records of 224 patients with 427 permanent teeth with luxations, followed up for a median period of 1.4 years (ranging from 11 days to 6.9 years) were analysed. Pulp outcomes - maintenance of pulp vitality, PCO and pulp necrosis were defined trough clinical and radiographic evaluation. A competing risk survival analysis was performed and cumulative incidence function (CIF) curves were build using the Aalen-Johansen estimator to assess the rates of each of the pulp outcomes during the follow-up period. The effect of independent variables including patient's gender and age at the time of trauma, tooth group and stage of root development, type of luxation, concomitant injuries, systemic antibiotic therapy (SAT) prescription, was evaluated using a cause-specific Cox regression model. Data were analysed in the R statistical program (version 4.0.4, Vienna, Austria, 2021). The results showed maintenance of pulp vitality in 38.2% of the sample (163 teeth), pulp necrosis in 28.1% (120 teeth) and OCP in 12.9% of the sample (55 teeth). The median time for the diagnosis of pulp necrosis was 3 months, while the time for pulp vitality was 8 months and for PCO was 16 months. The hazards of pulp vitality significantly decreased with the occurrence of concomitant coronal fractures (HR 0 .38 95% CI [0.2 ­ 0.8] p = 0.006). The hazards of pulp necrosis was significantly lower in teeth with a wide apical foramen (HR 0.62 95% CI [0.4 ­ 0.96] p = 0.03) but increased significantly in teeth with luxations associated with crown fractures (HR 4.0 CI 95% [2.6 - 6.1] p = 0.001) and in teeth with intrusive displacement (HR 2.3 CI 95% [1.2 - 4.1] p = 0.007). Teeth with lateral or extrusive luxations (HR 3.0 CI 95% [1.3 ­ 6.9] p = 0.001) or with a wide foramen (HR 2.4 CI 95% [1.2 ­ 4.7] p =0.01) showed the highest rates of PCO.