Autotrasplante dental. Una opción terapéutica contrastada / No disponible

El autotrasplante dental es una técnica clínica clásica que desde su protocolización por la escuela escandinava en los años 50 del pasado siglo permite obtener de forma predecible excelentes resultados. Si bien la introducción de los implantes dentales llevó a un cierto ostracismo a los autotrasplantes, progresivamente se ha ido reincorporando al armamentario clínico habitual como excelente método para reponer dientes ausentes. El índice de fracasos es bajo cundo se sigue un protocolo clínico estricto, que en los últimos tiempos incorpora el uso de réplicas 3D para minimizar el tiempo extraoral del diente donante. El momento ideal para realizar un autotrasplante se da cuando el diente donante tiene formado entre 2/3 y ¾ de la raíz, lo que permite que esta complete su desarrollo y mantenga la vitalidad pulpar. No obstante, es también posible realizar autotrasplantes de dientes con ápice cerrado, si bien en estos casos es imperativo realizar el tratamiento de conductos. El comportamiento de un diente autotrasplantado es idéntico al de cualquier otro diente, permite el crecimiento del hueso, e incluso movimientos ortodóncicos. En caso de pérdida de dientes en sector estético en pacientes jóvenes el autotrasplante es la opción de elección siempre que sea posible disponer de un diente donante

No disponible

Apical Papilla Cells Are Capable of Forming a Pulplike Tissue with Odontoblastlike Cells without the Use of Exogenous Growth Factors.

INTRODUCTION: Dental pulp is a complex tissue with highly differentiated cells, which makes its reconstruction a challenging task. The apical papilla is an undifferentiated tissue considered as the remnant of the dental papilla that forms the dentin-pulp complex. Aiming to analyze morphologic features of the tissue formed in an in vivo pulp model, we used human apical papilla as a cell source without the use of exogenous growth factors. METHODS: A construct was built using newborn mice molar crowns treated with TrypLE (Fisher Scientific, Loughborough, UK) and EDTA. The crowns were filled with PuraMatrix (Corning Inc, Corning, NY) and a pool population of human apical papilla cells. As a control, we used crowns filled only with PuraMatrix and empty crowns. The constructs were transplanted under severe combined immunodeficient mice kidney capsules. Immunohistochemistry for lamin A, dentin sialophosphoprotein, and dentin matrix protein 1 was performed. RESULTS: Morphologic analysis of all transplanted crowns showed the formation of a loose connective tissue of variable cellularity with the presence of well-formed functional vessels. In the study group, lamin A-positive cells represented the majority of cells within the pulp chamber and a few cells in the vessel lining. We also found positivity for dentin sialophosphoprotein and dentin matrix protein 1, an indicator of odontoblast differentiation. CONCLUSIONS: In our study model, human transplanted apical papilla cells mixed with the host cells and formed a vascularized viable tissue, and these cells were able to differentiate into odontoblastlike cells without the use of exogenous growth factors.

Success Rate of Autotransplantation of Teeth With an Open Apex: Systematic Review and Meta-Analysis.

PURPOSE: The aim of the present study was to determine the success rate of autotransplanted permanent teeth with an open apex and to identify the most influential prognostic factors. MATERIALS AND METHODS: A systematic search of the MEDLINE, EMBASE, LILACS, and SciELO databases was conducted for January 1990 to August 2015. The study eligibility criteria were primary studies that had evaluated patients with autotransplantation with an open apex, with or without preparation of the socket, and a minimum of 12 months of follow-up. The principal outcome was the success rate of autotransplanted teeth with an open apex. Two of us independently performed the selection process and data extraction. The Effective Public Health Practice Project's Quality Assessment Tool was used for the quality assessment of the studies. The odds ratio (OR) was calculated, with the 95% confidence interval (CI). RESULTS: A total of 21 studies were included in the present analysis. Of the 21 studies, 10 were retrospective and 11 were prospective. All the studies were of weak methodologic quality. The overall success rate was 89.68%, the survival rate was 98.21%, and the mean follow-up period was 6 years, 3 months (standard deviation 5.81 years). Among the prognostic factors analyzed, the premolars had a lower failure risk than did the molars (OR, 0.46; 95% CI, 0.25 to 0.84). The stage of development of the root and the autotransplantation receptor site showed no statistically significant differences. CONCLUSIONS: The overall success rate and survival were high, despite the methodologic limitations of the included studies. Further study is needed of the prognostic factors that influence the success of autotransplantation with an open apex.

Differentiation of Apical Bud Cells in a Newly Developed Apical Bud Transplantation Model Using GFP Transgenic Mice as Donor.

Rodent mandibular incisors have a unique anatomical structure that allows teeth to grow throughout the lifetime of the rodent. This report presents a novel transplantation technique for studying the apical bud differentiation of rodent mandibular incisors. Incisal apical end tissue with green fluorescent protein from transgenic mouse was transplanted to wild type mice, and the development of the transplanted cells were immunohistologically observed for 12 weeks after the transplantation. Results indicate that the green fluorescent apical end tissue replaced the original tissue, and cells from the apical bud differentiated and extended toward the incisal edge direction. The immunostaining with podoplanin also showed that the characteristics of the green fluorescent tissue were identical to those of the original. The green fluorescent cells were only found in the labial side of the incisor up to 4 weeks. After 12 weeks, however, they were also found in the lingual side. Here the green fluorescent cementocyte-like cells were only present in the cementum close to the dentin surface. This study suggests that some of the cells that form the cellular cementum come from the apical tissue including the apical bud in rodent incisors.

Enriched trimethylation of lysine 4 of histone H3 of WDR63 enhanced osteogenic differentiation potentials of stem cells from apical papilla.

INTRODUCTION: Dental tissue-derived mesenchymal stem cells (MSCs) are a reliable cell source for dental tissue regeneration. However, the molecular mechanisms underlying their directed differentiation remain unclear, thus limiting their use. Trimethylation of lysine 4 of histone H3 (H3K4Me3) correlates with gene activation and osteogenic differentiation. We used stem cells from apical papilla (SCAPs) to investigate the effects of genomic changes in H3K4Me3 modification at gene promoter regions on MSC osteogenic differentiation. METHODS: ChIP-on-chip assays were applied to compare the H3K4Me3 profiles at gene promoter regions of undifferentiated and differentiated SCAPs. Alkaline phosphatase activity assay, alizarin red staining, quantitative analysis of calcium, the expressions of osteogenesis-related genes, and transplantation in nude mice were used to investigate the osteogenic differentiation potentials of SCAPs. RESULTS: In differentiated SCAPs, 119 gene promoters exhibited >2-fold increases of H3K4Me3; in contrast, the promoter regions of 21 genes exhibited >2-fold decreases of H3K4Me3. On the basis of enriched H3K4Me3 and up-regulated gene expression on the osteogenic differentiation of SCAPs, WDR63 may be a potential regulator for mediating SCAP osteogenic differentiation. Through gain-of-function and loss-of-function studies, we discovered that WDR63 enhances alkaline phosphatase activity, mineralization, and the expression of BSP, OSX, and RUNX2 in vitro. In addition, transplant experiments in nude mice confirmed that SCAP osteogenesis is triggered by activated WDR63. CONCLUSIONS: These results indicate that WDR63 is a positive enhancer for SCAP osteogenic differentiation and suggest that activation of WDR63 signaling might improve tissue regeneration mediated by MSCs of dental origin.

Autotrasplante de tercer molar por un primer molar con periodontitis apical refractaria al tratamiento endodóntico / Autologous third molar to a first molar apical periodontitis refractory to endodontic treatment

Propósito: El presente caso describe el autotrasplante de tercer molar inferior en lugar de un primer molar inferior con diagnóstico de periodontitis apical persistente. Resumen: Paciente mujer de 20 años de edad que presenta un primer molar inferior en el que se había realizado tratamiento de conductos y que presentaba periodontitis apical persistente, se consideró inviable el retratamiento de conductos y se realizó el autotrasplante del tercer molar inferior derecho al espacio alveolar dejado por el primero. Se evaluó clínica y radiográficamente por 2 años, en donde se observó obliteración de la cavidad pulpar, anquilosis alveolodentaria, ausencia de reabsorción radicular, condiciones funcionales, integración de tejidos blandos y ausencia de enfermedad periodontal

Purpose: This case report describes the autologous mandibular third molar instead of a lower first molar diagnosed with persistent apical periodontitis. Summary: Female patient, 20 years of age having a first lower molar with persistent apical periodontitis refractory endodontic treatment. Retreatment was considered nonviable autologous conduit and right lower third molar alveolar space left by the first was made. We evaluated clinical and radiographically for 2 years, where obliteration of the pulp cavity, alveolar- dental ankylosis, no root resorption, functional conditions, soft tissue integration and no periodontal disease was observed. Conclusion: Autologous transplantation is a decibel option to replace teeth with persistent apical periodontitis in young patients

Colgajo de reposición apical / Apically positioned flap

Se describe la técnica del colgajo de reposición apical desde el primer autor, Nabers en 1954, así como las modificaciones realizadas por Ariaudo y Tyrrel en 1957 y Friedman en 1962. También se presenta un caso clínico donde se describen los diferentes pasos de la cirugía de reposición apical. Por último, se hace una revisión evaluando la eficacia del colgajo de reposición apical en el tratamiento de la periodontitis (AU)

This paper describes the technique apically positioned flap since the first author Nabers in 1954 and also the modifications performed by Ariaudo and Tyrrell in 1957 and Friedman in 1962. Also a clinical case is presented where it can be observed the different steps of the apically positioned flap in clinical pictures. Afterwards some papers in which the efficacy of the apically positioned flap in the treatment of periodontitis are evaluated and described (AU)

Characterization of rat apical tissues in different root development stage.

In this study, we try to compare the histological characteristics and the odontogenic capability of apical tissues (AT) at different root development stages of rat molar teeth. AT of mandibular first molars from 8-day-old, 21-day-old, and 35-day-old Sprague-Dawley rats were selected as being representative of root-initiating, root-forming, and root-completing stages, respectively. Cell counting, flow cytometry assays, alkaline phosphatase activity, alizarin red staining, and reverse transcription polymerase chain reaction were performed to assess the proliferation and mineralization potential of apical tissue cells at different stages of root development in vitro. In vivo transplantation of apical tissue cells combined with ceramic bovine bone was used to characterize the differentiation capacity. It was shown that there was a structurally and functionally dynamic change in the apical tissue of developing tooth root of rats, of which the unique developmental potential will reduce gradually with the ending up of root development. The AT of root-initiating and root-forming stage exhibited much higher proliferation and tissue-regenerative capacity than those of root-completing stage. Our present results indicate that the apical tissue, with the sustainable developmental ability throughout almost the whole process of tooth development, can yet be regarded as a competent candidate source for root/periodontal tissues regeneration.