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

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.

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.

Retalho posicionado coronalmente sem incisões relaxantes, associado a enxerto de tecido conjuntivo, para tratamento de retrações gengivais múltiplas / Coronally positioned flaps without relaxing incisions associated with a connective tissue graft to treat multiple gingival recessions

A retração gengival é caracterizada como o deslocamento apical da margem gengival em relação à junção cemento/esmalte (JCE), possuindo como consequência a exposição da superfície radicular. Diversas técnicas já foram descritas na literatura científi ca como tratamento para este problema gengival e, geralmente, a técnica cirúrgica de recobrimento radicular a ser escolhida relaciona-se com as características clínicas do caso, preferência do operador, habilidade manual, classifi cação da retração gengival, dentre outros. No entanto, a literatura indica que, dentre os procedimentos disponíveis, a técnica de retalho posicionado coronalmente com o uso de enxerto de tecido conjuntivo subepitelial parece ser a mais promissora. O objetivo deste trabalho foi apresentar um relato de caso de recobrimento radicular, utilizando a técnica de Zucchelli & De Sanctis associada a enxerto de tecido conjuntivo para recobrimento de retrações gengivais múltiplas. Paciente do sexo feminino, com 24 anos de idade, sem relato de alterações sistêmicas e/ou alergias, não etilista e não fumante, procurou tratamento odontológico queixando-se de hipersensibilidade dentinária e comprometimento estético bucal. Os resultados observados permitiram concluir que a técnica descrita por Zucchelli & De Sanctis, associada ao enxerto de tecido conjuntivo subepitelial, permitiu reduzir a altura das retrações gengivais, assim como aumentar e melhorar a qualidade do tecido gengival, com completa resolução da hipersensibilidade dentinária e alto nível de satisfação estética.

Gingival retraction is characterized as the apical displacement of the gingival margin in relation to the cementitious enamel junction (JCE), with consequent exposure to the root surface. Several techniques have already been described in the scientifi c literature as treatment for this gingival problem, and the surgical technique of root coverage to be chosen is generally related to the clinical characteristics of the case, operator preference, manual ability, classifi cation of gingival retraction, among others. However, the literature indicates that among the available procedures, the coronally positioned fl ap technique with the use of subepithelial connective tissue graft seems to be the most promising technique. The objective of this work is to present a case report of root coverage using the Zucchelli & De Sanctis technique associated with a connective tissue graft to cover multiple gingival retractions. Patient 24 years old, female, with no reports of systemic alterations and/or allergies, non-alcoholic and non-smoker, sought dental treatment complaining of dentine hypersensitivity and aesthetic impairment. The results showed that the technique described by de Zucchelli & De Sanctis associated with the subepithelial connective tissue graft reduced the height of gingival retractions, as well as increase and improve gingival tissue quality, with complete resolution of dentin hypersensitivity and high level of aesthetic satisfaction.

Doença peri-implantar: Abordagens contemporâneas / Peri-implant disease: contemporary approaches

O uso de implantes dentários é considerado uma revolução na Odontologia moderna. Entretanto, um dos grandes desafios encontrados na Implantodontia é o processo de reabsorção óssea ao redor dos implantes, após sua colocação ou durante o uso. Esta revisão teve por objetivo discutir alguns avanços nas pesquisas científicas que utilizam parâmetros clínicos para classificação da doença peri-implantar. Diversos estudos na literatura demonstram que essas ferramentas podem promover uma melhor compreensão, tanto do cirurgião-dentista quanto dos pacientes que necessitam da utilização desses.

The use of dental implants is considered a revolution in modern dentistry. However, the great challenges found at implantodontology is the process of bone resorption around implants after placement or during use. This review aims to discuss some advances in scientific research that use clinical parameters to classify peri-implant disease. Several studies in the literature demonstrate these tools can promote a better understanding for both dental surgeons and patients in need of this.

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.