Modification of polyetheretherketone (PEEK) physical features to improve osteointegration / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Polyetheretherketone (PEEK) has been widely applied in orthopedics because of its excellent mechanical properties, radiolucency, and biocompatibility. However, the bioinertness and poor osteointegration of PEEK have greatly limited its further application. Growing evidence proves that physical factors of implants, including their architecture, surface morphology, stiffness, and mechanical stimulation, matter as much as the composition of their surface chemistry. This review focuses on the multiple strategies for the physical modification of PEEK implants through adjusting their architecture, surface morphology, and stiffness. Many research findings show that transforming the architecture and incorporating reinforcing fillers into PEEK can affect both its mechanical strength and cellular responses. Modified PEEK surfaces at the macro scale and micro/nano scale have positive effects on cell-substrate interactions. More investigations are necessary to reach consensus on the optimal design of PEEK implants and to explore the efficiency of various functional implant surfaces. Soft-tissue integration has been ignored, though evidence shows that physical modifications also improve the adhesion of soft tissue. In the future, ideal PEEK implants should have a desirable topological structure with better surface hydrophilicity and optimum surface chemistry.

Instalación de implante y reparación de tabla ósea vestibular / Implant Setting and Vestibular Bone Board Repair

ABSTRACT Background: The occurrence of a vestibular bone lamina dehiscence of a fresh alveolus becomes a challenge for rehabilitation treatment of dental implants. Objective: To evaluate prosthetic treatment and stability of periimplant soft tissues in an alveolus with advanced oral bone resorption immediately after extraction, by using single fixed prostheses on a dental implant. Case presentation: A 29-year-old female patient, without systemic disease, completely toothed, with a thick-scalloped gingival biotype, attended the clinic and her main reason for consultation was not being aesthetically satisfied with her right upper central incisor. Radiographic examination showed advanced oral bone loss, secondary to an infection of the root of the right upper central incisor. In a first surgical phase, the right central incisor was extracted using a traumatic technique with periotomes, and a dental implant was placed. A resorbable membrane was adapted to the vestibular defect and the particulate cortical bone allograft was then compacted into the site in order to fill the space between the collagen membrane and the dental implant. A screw-retained provisional restoration was performed using the extracted natural tooth. The emergence profile was established simply by adding fluid composite resin, until the desired contours were achieved. Radiological and clinical follow-up at six months showed favorable implant evolution. No mechanical or biological complications were observed during this observation period. The oral gingival margin was in a correct position. Conclusion: This technique allowed predictable aesthetic-functional outcomes and soft tissue stability in a thick-scalloped gingival biotype with a single fixed prosthesis.

RESUMEN Antecedentes: La presencia de una dehiscencia de la lámina ósea vestibular de un alveolo fresco se convierte en un desafío en el tratamiento de la rehabilitación con implantes dentales. Objetivo: Evaluar el tratamiento protésico y la estabilidad de los tejidos blandos periimplantarios en un alveolo con reabsorción ósea bucal avanzada inmediatamente posterior a una extracción, mediante el uso de prótesis fijas unitaria sobre implante dental. Presentación del caso: Una paciente de 29 años de edad, sin enfermedad sistémica, completamente dentada, con un biotipo gingival festoneado grueso, asiste a la clínica y su principal motivo de consulta fue no estar conforme estéticamente en su incisivo central superior derecho. El examen radiográfico mostró la presencia de una pérdida ósea bucal avanzada, secundaria a una infección de la raíz del incisivo central superior derecho. En una primera fase quirúrgica, se extrajo el incisivo central derecho utilizando una técnica atraumática usando periótomos y se colocó un implante dental. Se adaptó una membrana reabsorbible al defecto vestibular y después se compactó el aloinjerto de hueso cortical particulado en el sitio para llenar el espacio entre la membrana de colágeno y el implante dental. Se realizó una restauración provisional atornillada utilizando el diente natural extraído. El perfil de emergencia se estableció simplemente agregando resina compuesta fluida, hasta que se lograron los contornos deseados. El seguimiento radiológico y clínico a los 6 meses mostró una evolución favorable del implante. No se observaron complicaciones mecánicas ni biológicas durante este periodo de observación. El margen gingival bucal estaba en una posición correcta. Conclusión: Esta técnica permitió resultados estéticos-funcionales predecibles y estabilidad de los tejidos blandos en un biotipo gingival festoneado grueso con una única prótesis fija.

Experimental study on the transforming growth factor β3 combined with dental pulp stem cells in early bone integration of implant / 中华口腔医学杂志

To establish the experimental model of rabbit mandibular anterior implant repair and evaluate the effects of transforming growth factor (TGF)-β3 and dental pulp stem cells (DPSC) in promoting the bone integration of implant. The New Zealand rabbits were randomly divided into experimental group, control group and blank group (6 rabbits for each group) . In the experimental group, the implant area was filled with the mixture of TGF-β3, DPSC and Bio-oss powder. In the control group, the implant area was filled with the mixture of DPSC and Bio-oss powder. In the blank group, the implant area was filled with the mixture of phosphate buffer solution and Bio-oss powder. Eighteen New Zealand rabbits were sacrificed in 2 weeks after procedure. The treated alveolar bone tissue was observed. The bone tissue around the implant were estimated by HE staining, immunocytochemical staining and real-time quantitative PCR. The implants were no shedding nor loose. HE staining shows the blank group had a sparse trabecular bone and a small amount of blood vessel around the implant and no obvious new bone formation. The control group showed that the bone trabecula around the implant was sparse and slender, the osteoblasts were arranged linearly around the trabecular bone, a small amount of new bone formation was found around the implant. In the experimental group, there were more thick and dense trabecular bone around the implant, the surrounding osteoblasts were arranged in clusters. The osteoblasts were active and many new bone formed. Typical bone lacunae, bone cells and a large number of new blood vessels can be observed. Immunohistochemistry showed that the proportion of average positive area in the experimental group, control group, blank group were (24.6±5.3) %, (11.3±2.8) % and (7.6±3.8) % respectively. The expression of bone sialoprotein in experimental group were significantly higher than the other 2 groups(0.000). Real-time quantitative PCR results showed that the expression level of Runt-related transcription factor 2 (RUNX2), type Ⅰcollagen (COL-Ⅰ), alkaline phosphatase in the experimental group was higher than in the blank group. The expression level of RUNX2 and COL-Ⅰ in the experimental group was higher than that of the control group (0.023). TGF-β3 has potential to promote the transformation of DPSC into osteoblasts, which can promote the integration of bone around the implant.

Experimental study on the transforming growth factor β3 combined with dental pulp stem cells in early bone integration of implant / 中华口腔医学杂志

Objective@#To establish the experimental model of rabbit mandibular anterior implant repair and evaluate the effects of transforming growth factor (TGF)-β3 and dental pulp stem cells (DPSC) in promoting the bone integration of implant.@*Methods@#The New Zealand rabbits were randomly divided into experimental group, control group and blank group (6 rabbits for each group) . In the experimental group, the implant area was filled with the mixture of TGF-β3, DPSC and Bio-oss powder. In the control group, the implant area was filled with the mixture of DPSC and Bio-oss powder. In the blank group, the implant area was filled with the mixture of phosphate buffer solution and Bio-oss powder. Eighteen New Zealand rabbits were sacrificed in 2 weeks after procedure. The treated alveolar bone tissue was observed. The bone tissue around the implant were estimated by HE staining, immunocytochemical staining and real-time quantitative PCR.@*Results@#The implants were no shedding nor loose. HE staining shows the blank group had a sparse trabecular bone and a small amount of blood vessel around the implant and no obvious new bone formation. The control group showed that the bone trabecula around the implant was sparse and slender, the osteoblasts were arranged linearly around the trabecular bone, a small amount of new bone formation was found around the implant. In the experimental group, there were more thick and dense trabecular bone around the implant, the surrounding osteoblasts were arranged in clusters. The osteoblasts were active and many new bone formed. Typical bone lacunae, bone cells and a large number of new blood vessels can be observed. Immunohistochemistry showed that the proportion of average positive area in the experimental group, control group, blank group were (24.6±5.3) %, (11.3±2.8) % and (7.6±3.8) % respectively. The expression of bone sialoprotein in experimental group were significantly higher than the other 2 groups(P=0.000). Real-time quantitative PCR results showed that the expression level of Runt-related transcription factor 2 (RUNX2), type Ⅰcollagen (COL-Ⅰ), alkaline phosphatase in the experimental group was higher than in the blank group. The expression level of RUNX2 and COL-Ⅰ in the experimental group was higher than that of the control group (P=0.023).@*Conclusions@#TGF-β3 has potential to promote the transformation of DPSC into osteoblasts, which can promote the integration of bone around the implant.

Tratamiento implantológico en paciente con periodontitis agresiva asociada a diabetes mellitus. Reporte de caso clínico. Fase quirúrgica / Implant treatment for a patient with aggressive periodontitis associated to diabetes mellitus. Clinical case report. Surgical phase

La diabetes mellitus es una enfermedad crónica degenerativa que se caracteriza por un conjunto de trastornos metabólicos y la presencia de hiperglicemia. Al analizar el efecto de la diabetes sobre los implantes se ha demostrado una alteración en los procesos de remodelación ósea y una deficiente mineralización, que se traduce en una menor oseointegración. El objetivo de este estudio es describir el manejo quirúrgico e implantológico que se llevó a cabo para restablecer la función y estética de una paciente con estas condiciones sistémicas y periodontales. Los resultados de las preservaciones de reborde y elevaciones de piso de seno maxilar lograron un reborde adecuado para la colocación de los implantes por medio de una guía quirúrgica tomográfica para su posterior rehabilitación con prótesis fijas implantoretenidas. Como conclusión tenemos que el diagnóstico tardío de la periodontitis agresiva puede llevar al edentulismo en pacientes jóvenes lo que puede ser solucionado con los implantes endoóseos.

Diabetes mellitus is a chronic degenerative disease characterized by a set of metabolic disorders and presence of hyperglycemia. When analyzing the effect of diabetes on implants, bone remodeling process alteration and deficient mineralization have been observed: these factors result in poorer bone integration. The aim of the present study was to describe surgical and implant treatment conducted in order to re-establish function and esthetics of a patient's periodontal and general circumstances. Resulting ridge (flange) preservation as well as elevation of the maxillary sinus achieved a suitable flange to place implants, by means of a tomographic surgical guide in preparation for further rehabilitation of implant-supported prostheses. As a conclusion we might propose that late diagnosis of aggressive periodontitis can lead to edentulism in young patients, which could be solved with endo-osseous implants.

Rehabilitación protésica de órbita implantosoportada en paciente con secuela de meduloepitelioma teratoide maligno / Implant-supported orbit prosthetic rehabilitation in patient with malignant teratoid medulloepithelioma

La prótesis maxilofacial es «la especialidad odontológica que se dedica a la rehabilitación estética de las estructuras intraorales y extraorales por medios artificiales¼.¹ Una prótesis orbital es un dispositivo artificial que reemplaza la ausencia del ojo y sus anexos (párpados, pestañas y cejas). Ésta es una alternativa a la rehabilitación cuando la reconstrucción quirúrgica no sea viable, o se prefiere por el paciente. Hoy en día, con el avance de la investigación, podemos contar con el uso de los implantes de oseointegración, los cuales hasta el momento han evidenciado ser el medio de fijación óptimo en la rehabilitación protésica craneofacial. El caso clínico que se presenta corresponde a un paciente masculino con secuelas postquirúrgicas orbitofaciales de un carcinoma derivado del sistema nervioso central (meduloepitelioma teratoide maligno), que tiene como principal tratamiento la exenteración del globo ocular y áreas circunscritas que se encuentren afectadas, dejando un defecto orbitofacial, el cual se rehabilitó con una prótesis maxilofacial retenida por implantes integrados al hueso del reborde supraorbitario. El objetivo de este trabajo es dar a conocer el tipo de tratamiento integral que se da a un paciente con estos antecedentes, desde el diagnóstico de la afección, el tratamiento de la misma, así como la rehabilitación protésica del defecto resultante, con lo que se demuestra las ventajas del uso de implantes de oseointegración como medio de retención de la prótesis, y finalmente se observa cómo este tipo de rehabilitación incrementa la apariencia estética del paciente con secuelas quirúrgicas faciales, logrando su reintegración a la sociedad con más confianza y seguridad. Para lograr un tratamiento exitoso y brindarle al paciente el bienestar físico y mental, debemos trabajar en conjunto con un equipo multidisciplinario que resuelva el caso en su totalidad, para finalmente ofrecer los beneficios reales de la rehabilitación protésica con un medio de retención que ha sido, sin duda, una ventaja más que ofrecer para el paciente portador de la prótesis orbitaria. El uso de implantes ha tenido un gran impacto en estos pacientes, dándoles una favorable reintegración a la sociedad, disimulando sus defectos faciales y brindándoles comodidad y seguridad en el ejercicio de sus actividades cotidianas, sin el temor de un posible desprendimiento de su prótesis.

Maxillofacial prosthesis can be described as «the specialty in dental science devoted to the aesthetic rehabilitation by artificial means of intra-and extra-oral structures¼.¹ Orbit prostheses are artificial devices used to substitute the absence of the eye and annex structures (eyelids, lashes and eyebrows). They represent a rehabilitation alternative when surgical reconstruction is either unviable or not preferred by the patient. In our days, in the light of recent research advances, we can make use of bone-integrated implants. To this date they have proven to be the best fixation means in craniofacial prosthetic rehabilitation cases. The clinical case introduced in the present study is that of a male patient exhibiting postsurgical orbital-facial sequels after a carcinoma derived from the central nervous system (CNS) (malignant teratoid medulloepithelioma). Main treatment for this type of carcinoma is ocular globe and circumscribed affected areas exenteration. In this case, this procedure left an orbital-facial defect which was rehabilitated with a maxillofacial prosthesis, fixated to the supraorbital ridge by bone-integrated implants. The aim of the present study was to describe the comprehensive treatment administered to a patient exhibiting this kind of history, from the moment when the condition was diagnosed, its treatment, and the prosthetic rehabilitation of the resulting defect. This study shows the advantages obtained when using bone-integrated implants as a means for prosthesis retention. It is equally observed how this type of rehabilitation greatly improves the aesthetic appearance of patients afflicted with surgical facial sequels, thus achieving a more confident and self-assured reinsertion into society. In order to achieve successful treatment and offer mental and physical welfare to the patient we must work alongside a multi-disciplinary team, to comprehensively solve the case. We can then finally offer the real advantages of prosthetic rehabilitation with a retention means which has proved to be an additional advantage for patients wearing orbital prostheses. Implant usehas bornea great impact in these patients, fostering favorable reinsertion into society, since facial defects are dissimulated and patients can exhibit comfort and security in their day-to-day activities, without fear of a possible prosthesis displacement.

Interacción entre osteoblastos y superficies de titanio:: aplicación en implantes dentales / Interaction between osteoblasts and titanium surfaces: application in dental implants

La oseointegración de un implante dental está condicionada por el tipo de material del implante, su topografía superficial y el tipo de recubrimiento. Aunque son varios los materiales utilizados para la fabricación de implantes dentales, actualmente el titanio es el material de preferencia por a su comportamiento inerte al entrar en contacto con los tejidos biológicos. Como la topografía superficial influye en la adhesión y proliferación celular, los implantes dentales son sometidos a tratamientos que crean irregularidades superficiales en la escala micro y sub-micrométrica. Así mismo, recubrimientos basados en minerales de origen orgánico son utilizados para mejorar la deposición de hueso sobre el implante. El objetivo de este estudio es realizar el cultivo de células osteoblásticas sobre sustratos de Ti-6Al-4V con cuatro tipos de superficies típicamente usadas en implantes dentales para determinar cuál de ellas tiene mejor comportamiento en términos de adhesión celular, proliferación celular y biomineralización. Las células osteoblásticas fueron cultivadas durante 24 horas para el ensayo de adhesión y durante 1, 2, 5, 6 y 7 días para el ensayo de proliferación. La biomineralización fue evaluada caracterizando mediante stereo zoom y SEM los depósitos de mineral coloreados mediante la técnica de tinción con alizarina roja. La cuantificación de estos depósitos de mineralización se realizó utilizando una herramienta de procesamiento de imágenes. Los resultados obtenidos revelan que las superficies rugosas y con recubrimiento poseen mejor comportamiento. Ninguna de las superficies estudiadas tuvo carácter tóxico para las células y todas presentaron perfiles de adhesión celular, proliferación celular y biomineralización

The bone integration of dental implants is dependent of type of material of implant, its superficial topography and also by the type of coating. Although there are many the materials used for the manufacture of dental implants, currently the titanium is the choice material by its inert behavior when it contact with biological tissues. As the superficial topography influenced on cellular adhesion and proliferation, the dental implants underwent treatments creating superficial irregularities in the micro and sub-micrometric scale. Likewise, the coats based on organic-origin minerals are used to improve the bone deposition on implant. The aim of present paper is to carry out the osteoblasts cells culture on Ti-6AI-4V substrates using four different types surfaces typically used in dental implants to determine which of them have the better behavior in terms of cellular adhesion, cellular proliferation and biomineralization. The osteoblasts cells were cultivated during 24 hr for the adhesion assay and during 1, 2, 5, 6 and 7 days for the proliferation assay. The biomineralization was assessed by characterization with estereozoom and SEM of the mineral depots colored using dying technique with red alizarin. The quantization of these mineralization depots was performed using a tool of images processing. The results obtained showed that the rough surfaces and coated have a better behavior. None of the study surfaces had a toxic character for cells and all showed cellular adhesion profiles, cellular proliferation and biomineralization