Limitaciones Técnicas del Método de Conteo de Anulaciones del Cemento para Estimación de Edad. Hallazgos a Partir de Una Revisión con Búsqueda Sistemática / Technical Limitations of Cementum Annulation Count Method for age Estimation. Findings From A Scoping Review

En la última década, la odontología forense se ha enfocado en el desarrollo de metodologías para la estimación de edad (EE) debido a la gran demanda en procesos identificatorios. Entre esas técnicas, el conteo de anulaciones del cemento dental (TCA) ha ofrecido resultados promisorios, pero también contradictorios que han generado dudas sobre su precisión y confiabilidad. El objetivo de este trabajo fue caracterizar, establecer alcances, e identificar las limitaciones del conteo de TCA según los actuales estándares normativos y metodológicos. Se realizó una revisión con búsqueda sistemática del método de conteo de TCA para EE incluyendo estudios experimentales y notas técnicas en las bases PubMed/Medline, Scopus, Web of Science (WoS) y Embase. Se emplearon los términos "estimation", "age" y "cementum", con búsqueda manual complementaria en Google Scholar. Se excluyeron revisiones, estudios en colecciones arqueológicas, estudios radiológicos y cartas al editor. La búsqueda arrojó un total de 273 artículos, seleccionándose 27 que cumplieron con los criterios de inclusión. La mayoría de los estudios fueron publicados en Asia, particularmente en India (n=21). Sólo 6 artículos declararon el número total de individuos, tipos de diente y de cortes histológicos, siendo el premolar el más estudiado. Apenas dos artículos evaluaron la calidad de la muestra a analizar mediante legibilidad de los cortes obtenidos. El test más empleado para evaluar la precisión del método fue el coeficiente de correlación de Pearson (n=21). Estos hallazgos exponen la alta heterogeneidad reportada en las metodologías de EE mediante conteo por TCA, por lo que aún no existe un proceso estandarizado que abarque todas sus etapas y entregue resultados confiables siguiendo los estándares jurídicos actuales para la evidencia científica. Un mayor control de las limitaciones técnicas detectadas aumentará el valor como prueba en un contexto identificatorio legal o forense.

SUMMARY: In the last decade, forensic odontology has focused on the development of age estimation (AE) methodologies due to the great request in identification processes. Among these techniques, the tooth cementum annulation (TCA) count method has offered promising but also contradictory results, raising questions about its accuracy and reliability. The aim of this work was to characterize, establish the scope, and identify the limitations of the TCA count method according to the current normative and methodological standards. A scoping review was carried out for TCA count methods for AE, including experimental studies and technical notes in the PubMed/Medline, Scopus, Web of Science (WoS) and Embase databases. The terms "estimation", "age" and "cementum" were used, with a complementary manual search in Google Scholar. Reviews, studies in archaeological collections, radiological studies and letters to the editor were excluded. The search yielded a total of 273 articles, selecting 27 of them that met the inclusion criteria. Most of the studies were published in Asia, particularly India (n=21). Only 6 articles declared the total number of individuals, types of teeth, and histological sections, with the premolar being the most studied. Only two articles evaluated the quality of the sample to be analyzed through the legibility of the cuts obtained. The most widely used test to assess the precision of the method was the Pearson correlation coefficient (n=21). These findings expose the high heterogeneity reported in EE methodologies by counting TCA, so there is still no standardized process that covers in all its stages and delivers reliable results following current legal standards for scientific evidence. More control of the detected technical limitations will increase the value as evidence in a legal or forensic identification context.

Glycogen synthase kinase 3 inhibition enhances mineral nodule formation by cementoblasts in vitro

Abstract This study aimed to investigate whether GSK-3 inhibition (CHIR99021) effectively promoted mineralization by cementoblasts (OCCM-30). OCCM-30 cells were used and treated with different concentrations of CHIR99021 (2.5, 5, and 10 mM). Experiments included proliferation and viability, cellular metabolic activity, gene expression, and mineral nodule formation by Xylene Orange at the experimental time points. In general, CHIR99021 did not significantly affect OCCM-30 viability and cell metabolism (MTT assay) (p > 0.05), but increased OCCM-30 proliferation at 2.5 mM on days 2 and 4 (p < 0.05). Data analysis further showed that inhibition of GSK-3 resulted in increased transcript levels of Axin2 in OCCM-30 cells starting as early as 4 h, and regulated the expression of key bone markers including alkaline phosphatase (Alp), runt-related transcription factor 2 (Runx-2), osteocalcin (Ocn), and osterix (Osx). In addition, CHIR99021 led to an enhanced mineral nodule formation in vitro under both osteogenic and non-osteogenic conditions as early as 5 days after treatment. Altogether, the results of the current study suggest that inhibition of GSK-3 has the potential to promote cementoblast differentiation leading to increased mineral deposition in vitro.

Using histological staining techniques to improve visualization and interpretability of tooth cementum annulation analysis / Uso de técnicas de tinción histológica para mejorar la visualización y la interpretación del análisis de la anulación del cemento dental

SUMMARY: The aim of the present study was to evaluate the effect of different staining techniques on applicability and accuracy of tooth cementum annulation (TCA) method. Nine decalcination techniques, 8 dehydration protocols and 8 different techniques were applied in 3 teeth from the persons of a known age. Black and white, and color images of histological sections were captured. An x- ray was taken of each tooth and they were photographed. Researchers were asked to observe both black/white and color images of histological sections. Researchers were divided into two groups. The first group analyzed histological images only, and the second group had photos of teeth and X-rays. In the first group of observers (without X ray) the differences in age estimation between real and observed age were significant for 2 younger patients, but not for the oldest patient, where the observed and real values matched. Of the 6 raters, the assesments of the last 3 (that used x-ray images together with histological sections) did not differ significantly from the real values. Extensive analysis and multiple repetitions performed in the present investigation revealed that the most optimal method of decalcification for TCA method was EDTA II for a period longer than 14 days at a section thickness of 2-3mm, while the most optimal protocol for dehydration was number IV. When it comes to staining, the most optimal staining protocol used for the cemental lines visualization and counting was Crocein Scarlet/Acid Fuchsin staining and Toluidine blue staining used at semithin section. Additional use of preexperimental evaluation employing x-ray of analyzed teeth decreased the errors of age estimation.

RESUMEN: El objetivo del presente estudio fue evaluar el efecto de diferentes técnicas de tinción sobre la aplicación y precisión del método de anulación de cemento dental (TCA). Se usaron nueve técnicas de descalcinación, 8 protocolos de deshidratación y 8 técnicas diferentes en 3 dientes de personas de edad conocida. Se capturaron imágenes en blanco y negro y en color de cortes histológicos. Se tomó una radiografía de cada diente y se fotografiaron. Los investigadores observaron las imágenes en blanco y negro y en color de las secciones histológicas. Los investigadores se dividieron en dos grupos; el primer grupo analizó solo imágenes histológicas y el segundo grupo tenía fotografías de los dientes y las radiografías. En el primer grupo de observadores (sin rayos X) las diferencias en la estimación de la edad entre la edad real y la edad observada fueron significativas para 2 pacientes más jóvenes, pero no para el paciente de mayor edad, donde los valores observados y reales coincidieron. De los 6 evaluadores, las valoraciones de los 3 últimos (que utilizaron imágenes de rayos X junto con cortes histológicos) no difirieron significativamente de los valores reales. El análisis exhaustivo y las múltiples repeticiones realizadas en la presente investigación revelaron que el método de descalcificación más óptimo para el método TCA fue EDTA II durante un período superior a 14 días con un grosor de sección de 2-3 mm, mientras que el protocolo óptimo para la deshidratación fue el número IV. En lo que respecta a la tinción, el protocolo de tinción más óptimo utilizado para la visualización y el recuento de las líneas de cemento fue la tinción con croceína escarlata / fucsina ácida y la tinción con azul de toluidina utilizada en la sección semifina. El uso adicional de la evaluación pre-experimental que emplea los rayos X de los dientes analizados disminuyó los errores de estimación de la edad.

Effects of cone beam computed tomography measurement of maxillary anterior teeth on implant success and patient satisfaction of maxillary anterior teeth / 中国基层医药

Objective:To investigate the effects of cone beam computed tomography measurement of maxillary anterior teeth on implant success and patient satisfaction of maxillary anterior teeth.Methods:120 patients who underwent maxillary anterior teeth implantation in Hangzhou Dental Hospital from October 2017 to October 2019 were included in this study. They were randomly assigned to receive either conventional maxillary anterior teeth implantation (control group, n = 60) or cone beam computed tomography measurement of maxillary anterior teeth and maxillary anterior teeth implantation (study group, n = 60). The implant success rate was compared between the two groups. Alveolar bone thickness and ISQ value immediately, 3 and 12 months after implantation as well as patient satisfaction were compared between the two groups. Results:Implant success rate in the observation group was significantly higher than that in the control group [96.67% (58/60) vs. 85.00% (51/60), χ2 = 4.904, P < 0.05]. In the observation group, alveolar bone thickness at 3 and 12 months after implantation was (1.53 ± 0.05) mm and (1.78 ± 0.12) mm, respectively, which was significantly higher than that in the control group [(1.46 ± 0.04) mm, (1.64 ± 0.10) mm, t = 9.839, 8.066, both P < 0.001]. In the observation group, ISQ value at 3 and 12 months after implantation was (76.83 ± 5.49) and (82.91 ± 4.85), respectively, which was significantly higher than that in the control group [(67.81 ± 4.61), (74.18 ± 5.21), t = 11.324, 11.038, both P < 0.001). Total satisfaction rate in the observation group was significantly higher than that in the control group [95.00% (57/60) vs. 81.67% (49/60), χ2 = 5.175, P < 0.05]. Conclusion:Cone beam computed tomography measurement of maxillary anterior teeth can help increase implant success rate and patient satisfaction.

Displasia cemento-óssea florida: relato de dois casos tratados por diferentes abordagen / Florid cemento-osseous dysplasia: report of two cases treated with different approaches

Objetivo: relatar dois casos de displasia cemento-óssea florida, descrevendo a evolução clínico-radiográfica ao longo de 5 anos em um paciente assintomático e a abordagem cirúrgica em um caso sintomático. Relato de caso 1: paciente, melanoderma, sexo feminino, 56 anos de idade, encaminhada ao Serviço de Cirurgia Bucomaxilofacial da Universidade Federal da Bahia, por cirurgião-dentista clínico que notou alterações imagiológicas em radiografia panorâmica de rotina. Apesar da importante extensão da lesão em maxila e mandíbula, não havia qualquer sintoma ou sinal clínico de infecção. A paciente foi acompanhada durante 5 anos, com exames de imagem bianuais e medidas clínicas profiláticas. Relato de caso 2: paciente, melanoderma, sexo feminino, 57 anos, apresentou-se ao ambulatório de cirurgia queixando-se de atraso em cicatrização após remoção de um dente. A radiografia panorâmica e a tomografia computadorizada, em conjunto com dados clínicos, permitiram o diagnóstico de displasia cemento-óssea florida com infecção secundária. A paciente foi abordada por meio de osteotomia em região do defeito em mandíbula. A análise microscópica do espécime obtido confirmou a alteração displásica cementoide. Os sinais e sintomas regrediram e a paciente segue em acompanhamento. Considerações finais: a displasia cemento-óssea florida, portanto, é uma doença pouco frequente, cujas manifestações podem demandar diferentes abordagens. É importante o domínio clínico do cirurgião-dentista, uma vez que o diagnóstico equivocado pode guiar a escolhas terapêuticas com resultados insatisfatórios. (AU)

Objective: the objective of this article is to report two cases of florid cemento-osseous dysplasia describing the clinical-radiographic evolution over 5 years in an asymptomatic patient and the surgical approach in a symptomatic one. Case report 1: patient, melanoderma, female, 56 years old, referred to the service by a clinical Dentist who noticed imaging alterations in a routine panoramic radiography. Despite the important extension of the maxillary and mandibular lesion, there was no clinical sign or symptom of infection. The patient has been followed for 5 years with biannual imaging exams and prophylactic clinical measures. Case report 2: patient, melanoderma, female, 57 years old, presented to the surgery outpatient complaining of delay in healing after removal of a tooth. Panoramic X-ray and Computed Tomography together with clinical data allowed the diagnosis of florid cemento-osseous dysplasia with secondary infection. The patient was approached through osteotomy in the region of the mandible defect. The microscopic analysis of the specimen confirmed the dysplastic cementenoid alteration. Signs and symptoms regressed and the patient is in follow up. Final considerations: florida cementoosseous dysplasia is an infrequent disease, whose manifestations may require different approaches. The clinical domain of the Dentist is important, since misdiagnosis can lead to therapeutic choices with unsatisfactory results. (AU)

Application of biological factor in cementum regeneration / 中华口腔医学杂志

At the present day, curettage and periodontal surgery comprise the main strategy for the treatment of periodontitis, however, these methods are limited in regenerating cementum. It has been found that some biological factors such asenamel matrix derivative (EMD), transforming growth factor-β (TGF-β) and insulin-like growth factor (IGF) could promote cementum regeneration. In the cementum regenerationstudies, there has been a lack of criteria to distinguish cementum from alveolar bone and other types of cementum. Therefore, this article will briefly review the biological factors that affect the cementum regeneration and the molecular markers used to judge the regenerating cementum.

Preparation of lithium-doped poly-glycerol sebacate scaffold and its properties / 吉林大学学报(医学版)

Objective:To prepare the lithium-doped poly-glycerol sebacate (PGS-Li) scaffold using the specific effects of lithium ions and the excellent performance of PGS, and to provide the basis for its application prospects in cementation tissue engineering scaffold.Methods:The scaffolds were divided into two groups.The PGS-Li scaffolds prepared by adding lithium phosphate during the PGS cross-linking process were used as PGS-Li group, and the PGS scaffolds synthesized by the equal-purification of sebacic acid and glycerol were used as PGS group.The molecular weights of the scaffolds in two groups were determined by gel permeation chromatography.The structures of the scaffolds in two groups were analyzed by fourier transform infrared spectroscope.The surface morphology and the porosities and the pore sizes of the scaffolds in two groups were observed by scanning electron microscope.X-ray photoelectron (XPS) spectroscope and inductively coupled plasma optical emission spectrometer were used to determine the Li ion contents in the scaffolds in two groups.Thermogravimetric analyzer was used to analyze the thermal stabilities of the scaffolds in two groups.Contact angle measuring instrument was used to compare the hydrophilicities of the scaffolds in two groups.In vitro weight loss test was used to determine the degradation rates of the scaffolds in two groups.The OCCM-30cells were divided into experimental group (added with PGS-Li scaffold extract) , PGS group (added with PGS scaffold extract) and blank control group (added with DMEM culture medium) .MTT assay was used to detect the proliferation activities of cells in various groups at different time (24, 48and 72h) ;the cell morphology was observed by calcein-AM staining.Results:The gel permeation chromatography results showed that the molecular weight of the PGS-Li scaffold was slightly larger than that of the PGS scaffold.The specific absorption peak of phosphate was detected in the fourier infrared spectrum of the PGS-Li scaffold.The scaffolds in two groups had irregular three-dimensional network structures under scanning electron microscope, and the pore size was 20-160μm, the porosity of PGS scaffold was (53.92±2.18) ％, and the porosity of PGS-Li scaffold was (53.58±1.73) ％, there was no statistical difference between two groups (P＞0.05) .The XPS results showed that a peak appeared at 54.9eV in PGS-Li group, which coincided with the Li 1s binding energy, while the inductively coupled plasma emission spectrometer results showed that the Li ion content in the PGS-Li scaffold was 0.084％.The thermogravimetric analysis results showed that PGS-Li scaffolds began to degrade at a higher temperature and ceased at a lower temperature compared with PGS scaffolds.The contact angle measurement results indicated that both the materials were hydrophilic materials;the contact angle of PGS scaffold meterial was 78.26°±2.00°, and the contact angle of the PGS-Li scaffold material was 69.78°±1.15°;there was statistical difference between two groups (P＜0.05) .The in vitro degradation experiments showed that the degradation rate of PGS-Li scaffolds was faster than that of PGS scaffolds.The proliferation activity of OCCM-30cells in PGS-Li group had no significant difference compared with PGS group and blank control group (P＞0.05) .The calcein-AM staining results showed the green fluorescence in the OCCM-30cells in PGS and PGS-Li groups, and there were no significant changes in the morphology of cementoblasts.Conclusion:PGS-Li scaffolds have similar composition and structure to PGS scaffolds, and have better performance in hydrophilicity and thermal stability.PGS-Li scaffolds have no effect on the proliferation of cementoblasts and have broad application prospects in cementum tissue engineering.

Isolation and characterization of a human cementocyte-like cell line, HCY-23

Abstract Cementum is the mineralized tissue covering the tooth root that functions in tooth attachment and post-eruptive adjustment of tooth position. It has been reported to be highly similar to bone in several respects but remains poorly understood in terms of development and regeneration. Here, we investigate whether cementocytes, the residing cells in cellular cementum, have the potential to be protagonist in cementum homeostasis, responding to endocrine signals and directing local cementum metabolism. Cells from healthy erupted human teeth were isolated using sequential collagenase/EDTA digestions, and maintained in standard cell culture conditions. A cementocyte-like cell line was cloned (HCY-23, for human cementocyte clone 23), which presented a cementocyte compatible gene expression signature, including the expression of dentin matrix protein 1 ( DMP1 ), sclerostin ( SOST ), and E11/gp38/podoplanin ( E11 ). In contrast, these cells did not express the odontoblast/dentin marker dentin sialoprotein ( DSPP ). HCY-23 cells produced mineral-like nodules in vitro under differentiation conditions, and were highly responsive to inorganic phosphate (Pi). Within the limits of the present study, it can be concluded that cementocytes are phosphate-responsive cells, and have the potential do play a key role in periodontal homeostasis and regeneration.

Microtensile bond strength of root canal dentin treated with adhesive and fiber-reinforced post systems

Abstract Nowadays, demand for esthetic restorations has risen considerably; thus, nonmetal esthetic posts made of either high-strength ceramics or reinforced resins, such as fiber-reinforced resin posts, have become more and more popular. Important characteristics of fiber-reinforced posts involve a modulus of elasticity similar to dentin and their ability to be cemented by an adhesive technique. A total of 36 maxillary incisors were divided into four groups. In this study, four adhesively luted fiber-reinforced (glass fiber, quartz glass fiber, zirconia glass fiber and woven polyethylene fiber ribbon) post systems were used. Post spaces were prepared by employing drills according to the protocol established for each group, and each post was adhesively luted with one of three adhesive systems. Three segments per root apical to the cementoenamel junction (CEJ) were obtained by sectioning the root under distilled water with a carbon spare saw. The samples (total of 108 sections) were 2.0±0.1 mm in thickness and they were stored individually in black film canisters with sterile distilled water. In order to determine the bond strength, the bonding area of each specimen was measured, and specimens were attached to a device to test microtensile strength at a speed of 1 mm/min. The analyses revealed no statistically significant differences between the adhesive systems and fiber-reinforced posts. (P> 0.05). However, the coronal portion of the root dentin had the highest bond strength. Adhesive systems used along with fiber-reinforced resin posts demonstrated reliable bonding.

Hipercementosis, una alteración de la estructura dentaria: recopilación bibliográfica / Hypercementosis, an alteration of the dental structure: bibliographic compilation

La hipercementosis se presenta como depósitos de cemento en la raíz de uno o más dientes. Siendo más frecuente en dientes que están sometidos a fuerzas de oclusión, particularmente en pacientes con enfermedad de Paget. El aumento de cemento se depositará en una banda que se encuentra situada alrededor del tercio apical de la raíz, es de ayuda útil realizar una evaluación radiográfi ca antes de una extracción dental (AU)

Hypercementosis occurs as cement deposits in the root of one or more teeth. Being more frequent in teeth that are subjected to occlusion forces or in patients with Paget's disease. The cement increase can be deposited in a band that can be found near the apical third of the root, it is a dental aid that a radiographic evaluation is made before a dental extraction (AU)

Análisis de las posibles interfases producidas en la fijación de postes de fibra de vidrio a la estructura dentaria / Analysis of the possible interfaces produced in the fixation of glass fiber posts to the tooth structure

En este trabajo se analizó el comportamiento de las posibles interfases producidas por algunos medios de fijación en la cementación de postes de fibra de vidrio. Para ello recurrimos a dos experimentos: Visualización microscópica de las posibles interfases y el análisis de la penetración de un colorante en la interfase del complejo dentina/ medio de fijación ­ poste de fibra de vidrio. Se conformaron tres grupos de diez unidades experimentales para cada experimento respectivamente. Los materiales con los que se trabajó presentan algún tipo de adhesión a la estructura dentaria. Ellos son el Cemento de Ionómero vítreo convencional, Cemento de resina con adhesivo dentinario y Cemento resinoso autoacondicionante. Con esta investigación se espera poder determinar cuál es el medio de fijación que posibilite la menor interfase en el complejo dentina-medio de fijación- poste de fibra de vidrio (AU)

In this work the behavior of the possible interfaces produced by some fixation media in the cementation of fiberglass poles was analyzed. To do this we used two experiments: Microscopic visualization of the possible interfaces and the analysis of the penetration of a dye in the interface of the dentin complex / fixation medium - glass fiber post. Three groups of ten experimental units were formed for each experiment, respectively. The materials with which they were worked present some type of adhesion to the dental structure. They are conventional Vitreous Ionomer Cement, Resin Cement with Dentin Adhesive and Self-Adhesion Resin Cement. With this research it is expected to be able to determine which is the fixation medium that allows the smallest interface in the dentine complex-fixation medium-fiber glass post (AU)

Effects of platelet-rich plasma on tooth replantation in dogs: a histologic and histomorphometric analysis

PURPOSE: The purpose of this study was to evaluate the effects of platelet-rich plasma (PRP) on periodontal healing of replanted root surfaces in dogs histologically and histomorphometrically. METHODS: A total of 36 roots of mandibular incisors and premolars from 6 mongrel dogs were used. The roots were randomly divided into 3 groups: 1) a positive control group (n=12), in which the periodontal ligament (PDL) and cementum were retained and the roots were soaked in saline; 2) a negative control group (n=12), in which the PDL and cementum were removed and the roots were soaked in saline; and 3) an experimental group (n=12), in which the PDL and cementum were removed and the roots were soaked in PRP. After soaking the root surfaces, the extracted roots were replanted into the extraction sockets. The roots were covered using a coronally repositioned flap RESULTS: Histologically, irregular-thickness PDL-like and cementum-like tissues were observed in the 4-week experimental group and the positive control group. PDL-like tissue and cementum-like tissue with a more uniform thickness were observed at 8 weeks. In the negative control group, PDL-like tissue and cementum-like tissue were rarely found, and root resorption and ankylosis were observed. In the cross-sectional histomorphometric analysis, the experimental group demonstrated a higher rate of formation of cementum-like tissue and a lower tooth ankylosis rate than the positive and negative control groups at 4 and 8 weeks. Although there was a significant difference in the tooth ankylosis rate and the formation of cementum-like tissue across the 3 groups (P 0.017). CONCLUSIONS: Applying PRP to root surfaces during tooth replantation in dogs can reduce tooth ankylosis and increase PDL-like and cementum-like tissue formation.

Progress in the diagnosis of florid cemento-osseous dysplasia / 中华口腔医学杂志

Florid cemento-osseous dysplasia (FLCOD) is a rare, extensive bone metabolism disorder, which occurs only in the jaw bone. It is usually asymptomatic for a long time and discovered incidentally during a radiological examination. The characteristics of FLCOD in the initial stages are similar to those of periapical granuloma or jaw cyst, which may lead to misdiagnosis. After the lesion is mature, the imaging findings show that radiopaque with a thin radiolucent peripheral halo, which is crucial for the diagnosis of FLCOD, but other jaw lesions have similar imaging findings. Due to the poor blood supply of the lesion, the alveolar bone of root apices of vital teeth is slow to heal after trauma, increasing the chance of infection, which can lead to the osteomyelitis of the jaws and emerge sequestrum. This paper reviews the aspects of pathogenesis, clinical characteristics, diagnosis, differential diagnosis and treatment.

Topical application of bFGF on acid-conditioned and non-conditioned dentin: effect on cell proliferation and gene expression in cells relevant for periodontal regeneration

Abstract Periodontal regeneration is still a challenge in terms of predictability and magnitude of effect. In this study we assess the biological effects of combining chemical root conditioning and biological mediators on three relevant cell types for periodontal regeneration. Material and Methods: Bovine dentin slices were conditioned with 25% citric acid followed by topical application of basic fibroblast growth factor (bFGF, 10 and 50 ng). We used ELISA to assess the dynamics of bFGF release from the dentin surface and RT-qPCR to study the expression of Runx2, Col1a1, Bglap and fibronectin by periodontal ligament (PDL) fibroblasts, cementoblasts and bone marrow stromal cells (BMSC) grown onto these dentin slices. We also assessed the effects of topical application of bFGF on cell proliferation by quantification of genomic DNA. Results: Acid conditioning significantly increased the release of bFGF from dentin slices. Overall, bFGF application significantly (p<0.05) increased cell proliferation, except for BMSC grown on non-conditioned dentin slices. Dentin substrate discretely increased expression of Col1a1 in all cell types. Expression of Runx2, Col1a1 and Fn was either unaffected or inhibited by bFGF application in all cell types. We could not detect expression of the target genes on BMSC grown onto conditioned dentin. Conclusion: Acid conditioning of dentin improves the release of topically-applied bFGF. Topical application of bFGF had a stimulatory effect on proliferation of PDL fibroblasts, cementoblasts and BMSC, but did not affect expression of Runx2, Col1a1, Bglap and fibronectin by these cells.

Cemento dental: aspectos atuais de interesse para o clínico / Dental cementum: current aspects to the clinicians

Embora tenha havido avanço no entendimento da homeostase do cemento dental, o papel deste tecido e sua biologia permanecem não completamente elucidados. Este estudo buscou fornecer informações sobre os conhecimentos mais recente relacionados à biologia do cemento dental, com o objetivo de discutir o papel exercido por este tecido em condições não fisiológicas nos tecidos periodontais. Devido aos avanços na exploração do tecido ósseo, que compartilha diversas características similares, a pesquisa abrangente sobre o cemento dental tem sido encorajada, a fim de esclarecer a função completa deste tecido na homeostase periodontal e regeneração. Desta forma, no presente trabalho, sempre que possível será feito um paralelo entre osso alveolar e cemento dental. O desenvolvimento de metodologias e técnicas celulares e moleculares avançadas possibilitou um melhor entendimento do comportamento do cemento em situações diversas, como quando em situações patológicas, como a doença periodontal, e até mesmo frente à regeneração tecidual. Ademais, estudos clínicos e em modelo animal demonstraram resultados em relação à formação de cemento em abordagens regenerativas. No entanto, sugere-se que estudos posteriores possam contribuir para um melhor conhecimento sobre o cemento e o perfil celular dos cementoblastos e cementócitos, bem como suas interações para fornecer novos insights para o desenvolvimento de terapias eficientes e mais previsíveis para regeneração dos tecidos periodontais. Apesar dos avanços dos estudos clínicos e laboratoriais, pôde-se concluir que inúmeras questões referentes à biologia do cemento permanecem não esclarecidas.

Although some progress has been made to understand dental cementum homeostasis, its role and biology remains not completely elucidated. This study aimed to provide information on the recent knowledge related to the dental cementum biology, in order to discuss the role of this tissue in physiological and non-physiological conditions in the periodontal tissues. Due to advances in the exploration of bone tissue, which shares several similar features, comprehensive research on dental cementum has been encouraged in order to clarify the complete function of this tissue in periodontal homeostasis and regenerative approach. Novel methodologies and advanced cellular and molecular techniques provided better understanding of cementum in different circumstances, as pathological situations such as periodontal disease and even tissue regeneration. In addition, clinical and animal model designs show positive outcomes to cementum formation in regenerative approaches, however, it is suggested that further studies may contribute to better understand cementum tissue and cementoblasts and cementocytes profile, as well as their interactions, providing new insights to develop efficient and more predictable therapies for periodontal tissue regeneration. Despite advances in clinical and laboratory studies, it can be concluded that many questions regarding the cementum biology remain unclear.

Cementoblastoma benigno: relato de caso / Benign Cementoblastoma: Case Report

O cementoblastoma benigno ou cementoma verdadeiro é uma neoplasia odontogênica benigna. Acredita-se que essa lesão é a única neoplasia verdadeira do cemento. Ela apresenta incidência entre 1 e 6,2% dentre os tumores odontogênicos, o que vem a tornála rara. Sendo assim, o objetivo do presente trabalho foi relatar o caso clínico de uma paciente com diagnóstico de cementoblastoma benigno, enfatizando as peculiaridades desse tumor, a importância do diagnóstico correto e o estabelecimento de um tratamento adequado, bem como ressaltar a importância da proservação do caso.

Benign cementoblastoma or true cementoma is a benign odontogenic tumour. It is believed that this lesion presents the unique true cementum neoplasm. It is a rare lesion comprising 1 to 6,2% of odontogenic tumours. Therefore, the objective of this study was to report the case of a patient diagnosed with benign cementoblastoma, emphasizing the peculiarities of this tumor, the importance of correct diagnosis and appropriate treatment setting, as well as underscoring the importance of proactive observation.

Effects of Er,Cr:YSGG laser on the root surface of periodontitis and healthy teeth / 北京大学学报(医学版)

Objective:To evaluate the effects of Er,Cr:YSGG laser on the root surface of periodontally involved teeth and healthy teeth,concerning the microstructure and the roughness.Methods:Eight freshly extracted teeth due to severe periodontitis and eight freshly extracted teeth due to orthodontic rea-sons or being third molar were chosen in this study.The root surface of each tooth was divided into four areas,and received four treatment methods:no treatment (control group );root planing with Gracey scaler for 30 seconds;irradiation by the lower power Er,Cr:YSGG laser;irradiation by the higher power Er,Cr:YSGG laser.Four periodontally involved teeth and four healthy teeth were used for the evaluation of microstructure using scanning electron microscope (SEM).The other four periodontitis teeth and four healthy teeth were used for the evaluation of roughness (Ra value )using 3 D profiler.Results:Smear layer was found on the teeth scaled by Gracey scaler,while the teeth irradiated by Er,Cr:YSGG laser demonstrated a melting surface with less smear layer.In the periodontitis teeth irradiated by the higher power,opening dentinal tubules could be observed.For the periodontally involved teeth,the Ra values of groups 1 to 4 were (237.4 ±20.0)nm,(1 35.7 ±1 1 .9)nm (P=0.01 ),(463.6 ±49.3)nm (P<0.001 )and (486.0 ±59.0)nm (P<0.001 )respectively.For the healthy teeth,the Ra values of groups 1 to 4 were (1 91 .4 ±44.5)nm,(1 31 .6 ±21 .5)nm (P=0.482),(463.7 ±34.6)nm (P<0.001 )and (470.3 ±1 21 .3)nm (P<0.001 )respectively.Conclusion:Er,Cr:YSGG laser can affect the microstructure of the cementum of the periodontitis teeth and healthy teeth.Irradiation by the Er,Cr:YSGG laser resulted in a melting surface with less smear layer and increased the roughness in the surface of root.

Understanding of Cementum Formation by the Wnt/β-Catenin Signaling / 치위생과학회지

Periodontal disease is one of the major dental diseases. Currently, various methods are used for healing and successful regeneration of periodontal tissue damaged by periodontal disease. The periodontal ligament and alveolar bone have received considerable interest for use in periodontal tissue regeneration and induction. However, as the functions of the factors required for tooth attachment and key regulatory factors for periodontal tissue regeneration in the cementum have recently been identified, interest in cementum formation and regeneration has increased. Dental cementum forms in the late phase of tooth development because of the reciprocal regulatory interaction between cervical loop epithelial cells and surrounding mesenchymal cells, which is regulated by various gene signaling networks. Many attempts have been made to understand the regulatory factors and cellular and molecular mechanisms associated with new cementum formation. In this paper, we reviewed the study outcomes to date on the regulatory factors that induce cementum formation and regeneration, focusing on understanding the roles and functions of Wnt signaling in the regulation of cementum formation. In addition, we aimed to obtain information on the useful reciprocal regulatory factors that mediate cementum formation and regeneration through a series of molecular mechanisms.

Effect of ERK1/2 signal pathway on the expression of OPG/RANKL in cementoblasts under stress stimulation / 解放军医学杂志

Objective To explore the effect of extracellular signal regulated kinase (ERK1/2) on the expression of osteoprotegerin/receptor activator of nuclear factor kB ligand (OPG/RANKL) in cementoblasts under mechanical tensile stress stimulation. Methods Using Flexcell FX4000T tension loading system and the ERK1/2-specific inhibitor PD98059, cementoblasts OCCM30 were randomly divided into four groups: group A (without loading and inhibitor), group B (without loading but inhibitor), group C (loading but without inhibitor), and group D (with both loading and inhibitor). The phosphorylation level of ERK1/2 was measured by Western blotting after 5, 15, 30 and 60min loading. OPG and RANKL mRNA were analyzed with fluorescent quantitative RT-PCR after 12h loading. Results Mechanical tensile stress activated ERK1/2 signal pathway of group C rapidly, and the P-ERK1/2 levels were significantly higher in group C than in group A at 5, 15 and 30min (P<0.05), then the P-ERK1/2 level of group C resumed to similar level of group A at 60min. The P-ERK levels of group B and D were significantly reduced by inhibitor PD98059. Tension stress up-regulated the expression of RANKL mRNA, and down-regulated the expression of OPG mRNA in OCCM30, the RANKL/OPG ratio increased after tension loading. With PD98059, the expression of RANKL mRNA decreased, that of OPG mRNA increased, and the RANKL/OPG ratio decreased (P<0.05). Conclusion ERK1/2 may be a signal transduction pathway for the regulation of OPG and RANKL expression after tension stress loading, but it is not the only one of activation pathways, and there maybe other common signal pathways involved in the regulation of OPG and RANKL expression.

Influência do plasma rico em plaquetas derivado do aspirado de medula óssea na cicatrização de defeitos periodontais: estudo histológico, histométrico e imunoistoquímico em ratos / Influence of platelet-rich plasma derived from bone marrow aspirate on the healing of periodontal fenestration defects: a histologic, histometric and immunohistochemical study in rats

Este estudo avaliou a influência do plasma rico em plaquetas derivado do aspirado de medula óssea (PRP-bma) na cicatrização de defeitos de fenestração periodontal (PFD) em ratos. PFD foram criados cirurgicamente na mandíbula de 40 ratos. Os animais foram divididos randomicamente em 2 grupos: C e PRP-bma – os defeitos foram preenchidos com coágulo sanguíneo ou PRP-bma, respectivamente. Os animais foram submetidos à eutanásia aos 10 ou 30 dias pós-operatórios. Foram realizadas análises histológica, histométrica e imunoistoquímica. A porcentagem de novo osso (NB), densidade do novo osso formado (DNB), novo cemento (NC) e extensão do defeito remanescente (ERD) foram avaliados histometricamente. Foram realizadas reações imunoistoquímicas para detecção de antígeno nuclear de proliferação celular (PCNA), sialoproteína óssea (BSP), osteocalcina (OCN) e fosfatase ácida resistente ao tartarato (TRAP). Células imunomarcadas foram quantificadas. Os dados foram analisados estatisticamente (ANOVA; Tukey, P < 0,05). Aos 10 dias, os grupos C e PRP-bma apresentaram quantidades similares de NB e DNB, e não foi observada formação de NC. Aos 30 dias, os grupos C e PRP-bma apresentaram quantidades similares de NB e DNB; o Grupo PRP-bma mostrou significativa formação de NC, com fibras colágenas inseridas obliquamente ou perpendicularmente à superfície radicular, sendo que nenhum espécime do Grupo C apresentou formação de NC. O Grupo PRP-bma apresentou um número significativamente maior de células PCNA-postivas (aos 10 dias) e BSP-positivas (aos 10 e 30 dias) que o Grupo C. Não foram observadas diferenças significativas no número de células OCN-positivas ou TRAP-positivas entre os grupos aos 10 ou 30 dias. Pode-se concluir que o PRP-bma promoveu formação de NC com ligamento periodontal funcional...

This study evaluated the influence of platelet-rich plasma derived from bone marrow aspirate (PRP-bma) on the healing of periodontal fenestration defects (PFD) in rats. PFD were surgically created in the mandible of 40 rats. The animals were randomly divided into 2 groups: C and PRP-bma – defects were filled with blood clot or PRP-bma, respectively. Animals were euthanized at either 10 or 30 days post-operative. Histologic, histometric and immunohistochemical analyses were performed. Percentage of new bone (NB), density of newly formed bone (DNB), new cementum (NC) and extension of remaining defect (ERD) were histometrically evaluated. Proliferating cell nuclear antigen (PCNA), bone sialoprotein (BSP), osteocalcin (OCN), and tartrate-resistant acid phosphatase (TRAP) immunohistochemical staining were performed. Immunolabeled cells were quantified. Data were statistically analyzed (ANOVA; Tukey, P < 0.05). At 10 days, groups C and PRP-bma presented similar amounts of NB and DNB, NC formation was not observed. At 30 days, groups C and PRP-bma presented similar amounts of NB and DNB; Group PRP-bma showed significant NC formation, with collagen fibers inserted obliquely or perpendicularly to the root surface, while NC formation was not observed in any Group C specimen. Group PRP-bma presented a significantly higher number of PCNA-positive (at 10 days) and BSP-positive cells (at 10 and 30 days) than Group C. No significant differences in the number of either OCN-positive or TRAP-positive cells were observed between groups at 10 or 30 days. It can be concluded that PRP-bma promoted NC formation with a functional periodontal ligament...