The mineralizing effect of zinc oxide-modified hydroxyapatite-based sealer on radicular dentin.

OBJECTIVE: The aim of this study was to evaluate the remineralization ability of three endodontic sealer materials at different root dentin regions. MATERIAL AND METHODS: Cervical, medial, and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin-based canal sealer, AH Plus; and gutta-percha. Remineralization, at the inner and outer zones of dentin disk surfaces, was studied by nanohardness (Hi) and Raman analysis. Nanoroughness and collagen fibrils width measurements were performed. Numerical data, at 24 h or 12 m, were analyzed by ANOVA and Student-Newman-Keuls (p < 0.05). RESULTS: At the outer and inner zones of the cervical dentin treated with oxipatite, the highest Hi after 12 m of immersion was achieved. The same group showed the highest intensity of phosphate peak, markers for calcification and crystallinity. Nanoroughness was lower and fibril diameter was higher at the inner zone of the dentin treated with oxipatite. Dentin mineralization occurred in every region of the root dentin treated with oxipatite and calcypatite, especially at the inner zone of the dentin after 12 m. CONCLUSIONS: Oxipatite reinforced the inner root zone at any third of the radicular dentin, by increasing both nanohardness and remineralization. When using calcypatite, the highest nanohardness was found at the apical third of the inner root dentin, but the lowest mechanical performance was obtained at the cervical and the medial thirds of the roots. Therefore, application of oxipatite as sealing cement of root canals is recommended. CLINICAL RELEVANCE: Oxipatite, when used as an endodontic sealing material, strengthens radicular dentin.

Hydroxyapatite-based cements induce different apatite formation in radicular dentin.

OBJECTIVE: To investigate crystallinity and ultrastructure of the formed hydroxyapatite at radicular cervical and apical dentin after being treated with three different canal sealers. METHODS: Cervical and apical root dentin surfaces were treated with two experimental hydroxyapatite-based sealers, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite) and an epoxy resin-based canal sealer (AH Plus); gutta-percha without sealer was included as control. Dentin surfaces were studied by X-ray diffraction and transmission electron microscopy through selected area diffraction and bright-field imaging after 24h and 12m of storage. RESULTS: Root cervical dentin treated with calcypatite and oxipatite produced poor crystallinity of new minerals, wide amorphous phase and non-stoichiometry. Reflections at the 002 plane and the corresponding diffraction rings attained lower values in the Scherrer equation and the Scherrer-Wilson equation in samples treated with both HAp-based sealers than in specimens without sealer or with AH Plus. At root cervical dentin treated with calcypatite, shorter and wider crystallite size formations and lower crystals grain size were found, if compared to those encountered at oxipatite treated dentin. Oxipatite attained improved crystallographic atomic order and less structural variation in both distances and angles. Apical dentin treated with oxipatite attained preferred grain orientation with polycrystalline lattices. SIGNIFICANCE: The immature crystallites formed in dentin treated with calcypatite and oxipatite will account for high hydroxyapatite solubility and remineralizing activity. New polycrystalline formations encountered in apical dentin treated with oxipatite may also produce high mechanical performance.

A zinc oxide-modified hydroxyapatite-based cement favored sealing ability in endodontically treated teeth.

OBJECTIVES: To evaluate the effectiveness of different endodontic canal sealers for dentin permeability reduction and to determine the viscoelastic performance of root dentin after their application. METHODS: Cervical, medial and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin- based canal sealer, AH Plus; and gutta-percha. Root dentin was evaluated for fluid filtration. Field emission scanning electron microscopy, energy dispersive analysis, AFM, Young's modulus and Nano-DMA analysis were also performed, at the inner and outer zones of dentin. RESULTS: Dentin treated with oxipatite showed the lowest microleakage among groups with hermetically sealed tubules and zinc-based salt formations. Samples treated with oxipatite showed the highest Ei at the cervical dentin third among groups, at 6 m of storage. Oxipatite promoted the highest complex modulus and tan delta values at the inner zone of both cervical and medial root dentin. Calcypatite favored the lowest tan delta outcomes at the inner zone of apical dentin at 6 m. CONCLUSIONS: Specimens treated with oxipatite showed the highest sealing ability, based on the highest Young's modulus and dentin mineralization, achieved by closing dentinal tubules, voids and pores that reinforced the inner zone of root dentin. The homogeneity of viscoelastic properties among the different root dentin thirds favored the energy dissipation without creating zones of stress concentration and micro-cracking which would have challenge micropermeability. Thereby, among the tested materials oxipatite is proposed as canal filling material and sealer in endodontics. CLINICAL SIGNIFICANCE: Oxipatite could be considered a good candidate for root canal filling material and sealer due to its improved long-term sealing ability and to the advanced remineralization, and so to the enhanced energy dissipation achieved at the inner zone of the radicular dentin.

A zinc-doped endodontic cement facilitates functional mineralization and stress dissipation at the dentin surface

BACKGROUND: The purpose of this study was to evaluate nanohardness and viscoelastic behavior of dentin surfaces treated with two canal sealer cements for dentin remineralization. MATERIAL AND METHODS: Dentin surfaces were subjected to: I) 37% phosphoric acid (PA) or II) 0.5 M ethylenediaminetetraacetic acid (EDTA) conditioning prior to the application of two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite), respectively. Samples were stored in simulated body fluid during 24 h or 21 d. The intertubular and peritubular dentin were evaluated using a nanoindenter to assess nanohardness (Hi). The load/displacement responses were used for the nano-dynamic mechanical analysis to estimate complex modulus (E*) and tan delta (δ). The modulus mapping was obtained by imposing a quasistatic force setpoint to which a sinusoidal force was superimposed. AFM imaging and FESEM analysis were performed. RESULTS: After 21 d of storage, dentin surfaces treated with EDTA+calcypatite, PA+calcypatite and EDTA+oxipatite showed viscoelastic discrepancies between peritubular and intertubular dentin, meaning a risk for cracking and breakdown of the surface. At both 24 h and 21 d, tan δ values at intertubular dentin treated with the four treatments performed similar. At 21 d time point, intertubular dentin treated with PA+oxipatite achieved the highest complex modulus and nanohardness, i.e., highest resistance to deformation and functional mineralization, among groups. CONCLUSIONS: Intertubular and peritubular dentin treated with PA+oxipatite showed similar values of tan δ after 21 d of storage. This produced a favorable dissipation of energy with minimal energy concentration, preserving the structural integrity at the dentin surface

COLOCACIÓN DE IMPLANTE DENTAL CON RELLENO ÓSEO BIOGRAFT-G® EN HUESO CON TRAUMA DENTOALVEOLAR. REPORTE DE CASO / PLACEMENT OF DENTAL IMPLANTS WITH OSSEOUS FILLER (BIOGRAFT-G®) IN BONE WITH DENTAL ALVEOLAR TRAUMA. CASE REPORT

En la actualidad, para el odontólogo resulta un gran desafío poder restaurar la apariencia natural y la anatomía de dientes perdidos. En este trabajo se realiza el reporte de un caso clínico donde se restituye el incisivo central superior derecho, a causa de traumatismo dentomaxilofacial, por un implante Leader® combinado con el relleno óseo Biograft-G®. Se trata de una paciente de 19 años atendida en la consulta multidisciplinaria del Centro Nacional de Estomatología, La Habana, Cuba. La paciente portaba prótesis inmediata a causa de la pérdida del diente 11 por fractura de corona y raíz, con defecto óseo vestibular. A la paciente le ocurría fractura frecuente de la prótesis, viéndose afectada desde el punto de vista estético, social, psicoafectivo y funcional. Después de una evaluación multidisciplinaria y el consentimiento de la paciente, se procedió a la cirugía mediante la técnica de colgajo, colocación de implante Leader® y relleno con Biograft-G® para regenerar el defecto óseo, devolver contorno vestibular y lograr una rehabilitación definitiva. Con este tratamiento, la paciente obtuvo los resultados estéticos y funcionales deseados.

Today is a challenge to restore the natural appearance and anatomy of extracted teeth. In this paper we present a clinical case in which the right upper central incisor is restored, due to the presence of a dentomaxillofacial trauma, through a Leader® implant combined with Biograft-G® bone filler. The patient is a 19 year woman treated in the multidisciplinary consultation of the National Center of Stomatology, Havana, Cuba. The patient had an immediate prosthesis due to a fracture of the crown and root, with vestibular bone defect. The patient frequently fractured the prosthesis, which affected her in terms of aesthetics, social, psychological and functional incorporation. After a multidisciplinary evaluation and the patient's consent, the surgery was performed using the flap technique, the placement of the Leader® implant and the filling with Biograft-G® to regenerate the bone defect, to recover the vestibular contour and to achieve a definitive rehabilitation. With this treatment, the patient obtained the desired aesthetic and functional results.

Experiencias en la aplicación de biomateriales en cirugía maxilofacial / Experiencies in the application of biomaterials in maxillofacial surgery

Se realizó un estudio prospectivo longitudinal para demostrar la efectividad del Apafill-G, HAP-2000 y Tisuacryl, biomateriales obtenidos en Cuba para el empleo de implantes óseos en lesiones osteolíticas maxilofaciales, como relleno de la cavidad ósea y en el cierre de heridas faciales y de la mucosa bucal originadas por trauma o tratamiento quirúrgico, con la finalidad de que estos sean de conocimiento y utilidad en las instituciones, servicios estomatológicos y sus especialidades. Un total de 389 pacientes fueron tratados quirúrgicamente. El biomaterial más usado fue el Tisuacryl, seguido por Apafill-G y HAP 2000. Los tratamientos quirúrgicos que predominaron fueron las extracciones múltiples, plastias auriculares, irregularidad ósea maxilar y mandibular, dientes retenidos y cirugía periapical. Los pacientes tratados quirúrgicamente evolucionaron de forma satisfactoria clínica y radiográficamente. Se concluyó que la aplicación de estos biomateriales producidos en Cuba en el cierre de heridas de los tejidos blandos y relleno de cavidades óseas, constituye una alternativa de tratamiento en cirugía bucal y maxilofacial; la hidroxiapatita cubana (Apafill-G y HAP-2000) utilizada en este estudio posee una alta biocompatibilidad y biofuncionabilidad, por lo que constituye un material implantológico ideal. No se reportaron reacciones adversas en los pacientes estudiados

Experiencias en la aplicación de biomateriales en cirugía maxilofacial / Experiencies in the application of biomaterials in maxillofacial surgery

Se realizó un estudio prospectivo longitudinal para demostrar la efectividad del Apafill-G, HAP-2000 y Tisuacryl, biomateriales obtenidos en Cuba para el empleo de implantes óseos en lesiones osteolíticas maxilofaciales, como relleno de la cavidad ósea y en el cierre de heridas faciales y de la mucosa bucal originadas por trauma o tratamiento quirúrgico, con la finalidad de que estos sean de conocimiento y utilidad en las instituciones, servicios estomatológicos y sus especialidades. Un total de 389 pacientes fueron tratados quirúrgicamente. El biomaterial más usado fue el Tisuacryl, seguido por Apafill-G y HAP 2000. Los tratamientos quirúrgicos que predominaron fueron las extracciones múltiples, plastias auriculares, irregularidad ósea maxilar y mandibular, dientes retenidos y cirugía periapical. Los pacientes tratados quirúrgicamente evolucionaron de forma satisfactoria clínica y radiográficamente. Se concluyó que la aplicación de estos biomateriales producidos en Cuba en el cierre de heridas de los tejidos blandos y relleno de cavidades óseas, constituye una alternativa de tratamiento en cirugía bucal y maxilofacial; la hidroxiapatita cubana (Apafill-G y HAP-2000) utilizada en este estudio posee una alta biocompatibilidad y biofuncionabilidad, por lo que constituye un material implantológico ideal. No se reportaron reacciones adversas en los pacientes estudiados(AU)

Síntesis de heridas bucofaciales con aplicación de tisuacryl / Synthesis of buccofacial wounds with application of tisuacryl

El empleo de adhesivo tisular tisuacryl para la síntesis de heridas bucomaxilofaciales favorece la hemostasia, nutrición, cicatrización de los bordes de la herida, rápida recuperación del tejido, disminución del edema y evita complicaciones como infección y reacción del tejido a cuerpo extraño. Se realizó la síntesis de heridas quirúrgicas o traumáticas sin necesidad de aplicar sutura a 171 pacientes que acudieron al Servicio de Cirugía Maxilofacial del Hospital General Clinicoquirúrgico Docente Aleida Fernández Chardiet de Güines, mediante un ensayo clínico fase III, de extensión terapéutica, multicéntrico, no controlado. Las técnicas quirúrgicas bucales fueron predominantes, la longitud de la herida fue de 6 cm en el (39 por ciento) de los casos. Los pacientes recibieron el tratamiento de forma ambulatoria y estuvieron conformes con los resultados obtenidos. Se evitó la acumulación en las heridas de suciedades, sudor, saliva y restos de alimentos, como ocurre cuando se emplean hilos de sutura y se logró la oclusión hermética de la herida. Se recomienda el uso del tisuacryl en heridas de los atletas. Se logran excelentes resultados cosméticos. El paciente no refiere las molestias ocasionadas por el material de sutura(AU9

The use of tisuacryl tissue adhesive for the synthesis of buccomaxillofacial wounds favors hemostasis, nutrition and cicatrization of the wound edges, fast recovery of the tissue, reduction of the edema and prevents complications such as infection and histic reaction to foreign body. The synthesis of surgical or traumatic wounds was performed without applying suture among 171 patients that attended the Maxillofacial Surgery Service of "Aleida Fernández Chardiet" General Clinical and Surgical Hospital, in Güines, by an uncontrolled multicenter stage III clinical trial of therapeutic extension. The buccal surgical techniques predominated and the length of the wound was of 6 cm (39 por ciento). The patients received ambulatory treatment and were satisfied with the results. The accumulation of dirtiness, sweat, saliva and food debris in the wounds, as it occurs when suture thread are used, was avoided. The hermetic occlusion of the wound was attained. The use of tisuacryl is recommended for athletes' wounds. Excellent cosmetic results are achieved. The patient does not refer to the annoyances caused by the suture material(AU)

Síntesis de heridas bucofaciales con aplicación de tisuacryl / Synthesis of buccofacial wounds with application of tisuacryl

El empleo de adhesivo tisular tisuacryl para la síntesis de heridas bucomaxilofaciales favorece la hemostasia, nutrición, cicatrización de los bordes de la herida, rápida recuperación del tejido, disminución del edema y evita complicaciones como infección y reacción del tejido a cuerpo extraño. Se realizó la síntesis de heridas quirúrgicas o traumáticas sin necesidad de aplicar sutura a 171 pacientes que acudieron al Servicio de Cirugía Maxilofacial del Hospital General Clinicoquirúrgico Docente "Aleida Fernández Chardiet" de Güines, mediante un ensayo clínico fase III, de extensión terapéutica, multicéntrico, no controlado. Las técnicas quirúrgicas bucales fueron predominantes, la longitud de la herida fue de 6 cm en el 39 (por ciento) de los casos. Los pacientes recibieron el tratamiento de forma ambulatoria y estuvieron conformes con los resultados obtenidos. Se evitó la acumulación en las heridas de suciedades, sudor, saliva y restos de alimentos, como ocurre cuando se emplean hilos de sutura y se logró la oclusión hermética de la herida. Se recomienda el uso del tisuacryl en heridas de los atletas. Se logran excelentes resultados cosméticos. El paciente no refiere las molestias ocasionadas por el material de sutura(AU)