Preparation of an amino hybrid mesoporous silica-based nanotopography protective coating on a titanium implant surface and evaluation of its osteogenic effect / 口腔疾病防治

Objective@#To deposit degradable amino-hybrid mesoporous silica (AHMS) in situ on the surface of titanium nanotube (TNT) and explore its protective effect on nanomorphology and osteogenesis.@*Methods@#TNT and TNT@AHMS were sequentially prepared via an anodizing method: the oil-water two-phase method (experimental group) and the acid-etched titanium method [control group (Ti)]. The parameters for synthesis were explored by changing the silicon source dosage ratio (3∶1, 1∶1, 1∶3); the surface morphology was observed by scanning electron microscope(SEM), hydrophilicity was detected by Water Contact Angle Tester, elemental composition was detected by X-ray photoelectron spectroscopy (XPS); nanoindentation test and ultrasonic oscillator were used to observe the morphological holding effect as mechanical strength of TNT@AHMS in vitro; simulated immersion experiments in vitro was used to observe the degradation behavior of the material. the MC3T3-E1 cell line was used to observe the effect of cell adhesion, proliferation and differentiation on the material; and an SD rat femoral implant model and micro-CT were used to verify the protective effect and osseointegration effect of AHMS on TNT morphology.@*Results@#The morphologies of TNT and TNT@AHMS were successfully prepared, and the silicon source ratio was 1:3. SEM showed that the titanium nanotubes were uniformly covered with AHMS coating, and the mesoporous pore size was about 4 nm. After AHMS was incorporated, the surface of the material was hydrophilic (12.78°), the presence of amino groups (NH2-) was detected, the material was completely degraded within 12 h in vitro, and the active morphology of the TNT was re-exposed with a cumulative silicon release of 10 ppm. Nanoindentation test showed that TNT@AHMS exhibited more ideal surface mechanical strength. SEM revealed that TNT maintains its own morphology under the protection of AHMS, and the TNT group suffered severe exfoliation. In addition, the early adhesion and proliferation rates, ALP activity, and bone volume fraction of cells on the TNT@AHMS surface 4 weeks after implantation were significantly higher than those in the TNT group.@*Conclusion@#By depositing AHMS on the surface of TNT, the nanotopography can be protected. It not only prevents the active base topography from exerting subsequent biological effects but also further endows the material with the ability to promote bone regeneration, laying a foundation for the future development of nanotopography-modified titanium implants.

Comparative Assessment of Contact Osteogenesis at the Titanium Implant-Bone Junction in Male Rabbits with Dissimilar Femoral Defects / Evaluación Comparativa de la Osteogénesis de Contacto en la Unión entre el Hueso y el Implante de Titanio en Conejos Macho con Defectos Femorales Diferentes

SUMMARY: Traumatized bone tissue has the capacity to repair itself so that it eventually regains its almost original form, even in the case of artificially inserted implants. The process that stays at the base of the regeneration is represented by osteogenesis or remote osteogenesis. The major difference between the two types of bone formation is the location of the cement line, which is located on the surface of the implant for contact osteogenesis and on the surface of the bone defect for remote osteogenesis. The aim of the present study was to assess the contact osteogenesis in the case of inserted titanium screws in holes with diameters of 1.8 mm and 1 mm respectively. The obtained results show, in the case of the groove with 1.8 mm that the newly proliferated bone represents 73.85 % of the total area, while in the case of the groove with 1 mm in diameter the value of the newly proliferated bone is 26.15 %. In conclusion, the insertion of titanium screws by self-tapping into the hole smaller than the core of the screw is accompanied by bone proliferation by contact osteogenesis much more modest than in the case of insertion into the hole larger than the core of the screw.

El tejido óseo traumatizado tiene la capacidad de reparar en forma espontánea, de modo que eventualmente recupera su forma casi original, incluso en el caso de implantes insertados artificialmente. El proceso que queda en la base de la regeneración está representado por la osteogénesis u osteogénesis a distancia. La principal diferencia entre los dos tipos de formación ósea es la ubicación de la línea de cemento, que se encuentra en la superficie del implante para la osteogénesis de contacto y en la superficie del defecto óseo para la osteogénesis remota. El objetivo del presente estudio fue evaluar la osteogénesis de contacto en el caso de tornillos de titanio insertados en forámenes con diámetros de 1,8 mm y 1 mm respectivamente. Los resultados obtenidos muestran, en el caso del surco de 1,8 mm que el hueso neoproliferado representa el 73,85 % del área total, mientras que en el caso del surco de 1 mm de diámetro el valor del hueso neoproliferado es del 26,15 %. En conclusión, la inserción de tornillos de titanio por autorroscantes en el foramen menor que el núcleo del tornillo se acompaña de una proliferación ósea por osteogénesis de contacto mucho más modesta que en el caso de la inserción en el foramen mayor que el núcleo del tornillo.

Regulación de la implantología dental en México / Regulation of dental implantology in Mexico

Introducción: los implantes dentales se han convertido en uno de los tratamientos odontológicos con mayor demanda en todo el mundo, no sólo por el nivel máximo de funcionalidad y de estética, sino también debido a su estabilidad, osteointegración y facilidad en su rehabilitación. Es incierto si los implantes dentales se encuentran normados formalmente en México, lo que motiva a la revisión del estado actual. Objetivo: evidenciar el estado actual de la legislación de la práctica de la implantología dental en México a través de una revisión en la literatura. Material y métodos: revisión de las legislaciones existentes en México para la aplicación de implantes dentales y su contraparte en el mundo a través de la evaluación de normas expedidas en América y Europa. Resultados: se contabilizó un total de 17 escuelas de implantes dentales que cuentan con el reconocimiento de la Secretaría de Educación Pública, de las cuales tres son públicas y 14 privadas. Se presentó una discrepancia en los planes de estudio que va de 16 a 36 meses. Las escuelas no contaron con un aval normativo. Las normas internacionales para control de calidad y aplicación de la tecnología en implantes se ubicaron en Canadá, Estados Unidos, España, Reino Unido y Francia. Conclusiones: contar con un antecedente normativo establecido por los países de primer mundo y ausente en México permite evidenciar la necesidad de implementar una Norma Oficial Mexicana que regule la fabricación, distribución y almacenamiento de los implantes dentales en México. A la vez, la revisión sugiere que la Secretaría de Educación Pública norme los créditos mínimos necesarios en las instituciones educativas reconocidas para la formación de recursos humanos que ejercen la implantología dental (AU)

Introduction: dental implants have become one of the dental treatments with the highest demand in the world, not only because of the highest level of functionality and aesthetics, but also because of their stability, osseointegration and ease of rehabilitation. It is uncertain if dental implants are formally regulated in Mexico, which motivates the review of the current status. Objective: to demonstrate the current state of the legislation for the practice of dental implantology in Mexico through a review of the literature. Material and methods: review of the existing legislation in Mexico, for the application of dental implants and its counterpart in the world, through the evaluation of standards issued in America and Europe. Results: a total of 17 dental implant schools that have the recognition of the Ministry of Public Education were counted, of which 3 are public and 14 private. There was a discrepancy in the study plans that ranged from 16 to 36 months. Schools will not have regulatory backing. The international standards for quality control and application of technology in implants were located in Canada, the United States, Spain, the United Kingdom and France. Conclusions: having a normative antecedent established by the countries of the first world and absent in Mexico, allows to demonstrate the need for the implementation of an Official Mexican Standard, which regulates the manufacture, distribution and storage of dental implants in Mexico. At the same time, the review suggests that the Ministry of Public Education regulate the minimum necessary credits in recognized educational institutions, for the training of human resources that practice dental implantology (AU)

Angiogenic property of cobalt and calcium-phosphorus doped coating on titanium surfaces in vitro / 口腔疾病防治

Objective@# To investigate the effect of cobalt (Co) and calcium-phosphate (Ca/P) doped coating on titanium surfaces and their angiogenic effect.@*Methods @# Microarc oxidation (MAO) was used to prepare Co-Ca/P-doped and Co-doped coatings. Titanium (Ti) sheet without MAO treatment was used as control. Scanning electron microscopy (SEM) was used to observe the surface micromorphology of the coatings. Energy dispersive spectrometry (EDS) was also applied to detect the doped chemicals and their contents. Standard soaking solutions of these coatings were prepared using an endothelial cell medium (ECM) solution for subsequent angiogenesis experiments. Human umbilical vein endothelial cells (HUVECs) were cultured on Matrigel with ECM soaking solutions for 4 h and 8 h. The microvessels were observed under a microscope, and the number of microtubules and their interconnecting nodes were analyzed with Image J software. @*Results@# Co doped and Co-Ca/P-doped coatings were successfully prepared by MAO, which was demonstrated by both SEM observation and EDS analysis. SEM observation showed that irregular crystals of the above chemicals were present on both Co and Co-Ca/P-doped coatings, commonly with a diameter <2 μm. However, more crystals were observed on the Co-Ca/P coatings than on the Co coating, and the distribution of the crystals was more homogenous on the Co-Ca/P coatings. However, only polishing scratches were observed on the Ti sample surface. EDS analysis indicated that in contrast to only Co in the Co coating, Co, Ca and P were doped within the Co-Ca/P coating, and none of the three elements were observed on the Ti plate surface. The number of vascular rings and nodes formed by HUVECs in the extract of the Co-Ca/P group was significantly higher than that of the Co group (P<0.05), and the angiogenic effect of these two components was significantly better than that of the Ti group (P<0.05). @*Conclusion@#The Co-Ca/P coating exhibits good angiogenic properties in vitro and is valuable for the development of new titanium implants with high surface bioactivity.

The influence of haematogenous bone marrow on the early osseointegration of a titanium implant which penetrates the endosteum / La influencia de la médula ósea hematógena en la osteointegración temprana de un implante de titanio que penetra en el endostio

SUMMARY: The utility of metallic bio-medical implants in osseous or dental affections is irrefutable. The paper aims to test the tolerance of the bone marrow to titanium implants. Titanium implants were inserted in the femur of 11-months old rabbits. The implants penetrated the endosteum, half of their length getting into the haematogenous bone marrow. Seven days after the insertion we collected bone fragments containing the implant. The CT exam revealed a significant decrease in the density of the bone at the interface with the implant and a more discrete one aloof from the insertion area. The histologic exam after 7 days revealed osseous reparatory processes only in the endosteal area from where it expanded on the surface of the implant which was inside the marrow. The presence and intensity of the osseous reparatory processes after only seven days post-implant demonstrates that the marrow actively participates in bone regeneration and implants osseointegration.

RESUMEN: La utilidad de los implantes biomédicos metálicos en afecciones óseas o dentales es irrefutable. El documento tiene como objetivo probar la tolerancia de la médula ósea a los implantes de titanio. Se insertaron implantes de titanio en el fémur de conejos de 11 meses. Los implantes penetraron en el endostio y la mitad de su longitud penetró en la médula ósea hematógena. Siete días después de la inserción, recolectamos fragmentos de hueso que contenían el implante. El examen de TC reveló una disminución significativa en la densidad del hueso en la interfaz con el implante y una más discreta alejada del área de inserción. El examen histológico a los 7 días reveló procesos de reparación ósea solo en el área endóstica desde donde se expandió en la superficie del implante que estaba dentro de la médula. La presencia e intensidad de los procesos de reparación ósea después de solo siete días del implante demuestra que la médula ósea participa activamente en la regeneración ósea y en la osteointegración de los implantes.

Research progress on enhancing biological activity of titanium implants by chairside ultraviolet photofunctionalization / 口腔疾病防治

@#Excellent mechanical properties and biocompatibility resulted in titanium and titanium alloys being widely used in the medical field. However, the biological activity of atitanium surface will gradually fade with increasing exposure time, which affects its final osseointegration. As an effective surface modification method, ultraviolet (UV) photofunctionalization does not change the surface morphology of implants and is a suitable surface treatment for many brands of implants. This article summarizes the research progress on the effect of UV photofunctionalization technology on the characteristics of titanium surfaces, biological activity and implant osseointegration, as well as its current clinical applications. Studies have shown that the superhydrophilicity of the titanium surface and improved biological activity endowed by UV photofunctionalization can accelerate and enhance bone formation, resulting in a higher success rate of implant surgery. Therefore, UV photofunctionalization has great potential for clinical chairside applications.

Fabrication of rough surface on titanium using electrochemical treatment in NaCl electrolyte / 대한치과재료학회지

It is difficult to get sufficient roughness on titanium implant surface using traditional electrochemical treatments. In this study, we have developed a new method which provides a hybrid structured titanium surface having micro/nano roughness using electrochemical treatment in NaCl electrolyte and hydrothermal treatment. Titanium disks were anodically oxidized (ANO) in 0.15M NaCl electrolyte by applying positive electric pulses. The oxide compounds loosely attached to the surface were removed by ultrasonic cleaning (ANO group). These specimens were hydrothermally (HT) treated in an alkaline solution (ANO-HT group). ANO group showed the dimpled grain surfaces with a diameter of approximately 30 µm, and its roughness (Ra) was about 2.4 µm. The nano-sized crystallites which had an anatase TiO₂ crystalline structure were uniformly distributed on the surface of ANO-HT group. This group still retained high roughness (~2.7 µm) similar to ANO group and showed high hydrophilicity. Titanium surface with high roughness and hydrophilicity was fabricated using new electrochemical treating method and hydrothermal treatment. This surface modification method could be used for enhancing the osteoconductivity of the titanium implants.

Selective laser sintering and performances of porous titanium implants / 华西口腔医学杂志

OBJECTIVE@#This work aims to analyze the mechanical properties and biocompatibility of porous titanium (Ti) implants fabricated by selective laser sintering (SLS) and investigate the promotion of osseointegration by porous titanium implant combined with chitosan (CS)/hydroxyapatite(HA) composite coating.@*METHODS@#Ti6Al4V specimens were prepared, and CS/HA composite coating was fabricated on the surface of a portion of the specimens. The mechanical properties of the samples were observed by scanning electron microscope. MC3T3-E1 cells were cultured in vitro, and their biological properties in vitro were analyzed using live and dead viability cell staining method, methyl thiazolyl tetrazolium (MTT) staining, and alkaline phosphatase (ALP) level detection. The thread implant specimens were implanted in the femoral condyle of rabbits, and biological performance was evaluated in vivo.@*RESULTS@#Quasi-elastic gradient of porous specimens decreased with increasing porosity, and the quasi-elastic gradient were close to cortical and cancellous bone when the porosities were 30% and 70%. The specimens showed good biocompatibility. Combined with CS/HA coating, the implants promoted the proliferation and differentiation of MC3T3-E1 cells and facilitated the entry of bone tissue into pores and good osteogenesis.@*CONCLUSIONS@#The porous titanium implant exhibited favorable mechanical properties and biocompatibility. Combined with CS/HA coating, the implant exhibited bone inducibility, which leads to stable osteogenesis.

Osteogenic Nanofibrous Coated Titanium Implant Results in Enhanced Osseointegration: In Vivo Preliminary Study in a Rabbit Model

A titanium implant surface when coated with biodegradable, highly porous, osteogenic nanofibrous coating has shown enhanced intrinsic osteoinductive and osteoconductive properties. This coating mimics extracellular matrix resulting in differentiation of stem cells present in the peri-implant niche to osteoblast and hence results in enhanced osseointegration of the implant. The osteogenic nanofibrous coating (ONFC) consists of poly-caprolactone, gelatin, nano-sized hydroxyapatite, dexamethasone, ascorbic acid and beta-glycerophosphate. ONFC exhibits optimum mechanical properties to support mesenchymal stem cells and steer their osteogenic differentiation. ONFC was subjected to various characterization tests like scanning electron microscopy, Fourier-transform infrared spectroscopy, x-ray diffractometry, thermal degradation, biomineralization, mechanical properties, wettability and proliferation assay. In pre-clinical animal trials, the coated implant showed enhanced new bone formation when placed in the tibia of rabbit. This novel approach toward implant bone integration holds significant promise for its easy and economical coating thus marking the beginning of new era of electrospun osteogenic nanofibrous coated bone implants.

Local injection of exogenous nerve growth factor improves early bone maturation of implants / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of nerve growth factor (NGF) in the osteogenic action of implants and the maturation and reconstruction changes in bone tissues in the early stage of osseointegration.</p><p><b>METHODS</b>The mouse implant model was established by placing titanium in the femoral head of the mouse and locally injecting NGF in the implant zone. On 1, 2 and 4 weeks after operation, stain samples were collected from animals using hematoxylin-eosin (HE) staining and Masson staining. The effect of NGF on the bone maturation was compared at different time points of early stage osseointegration.</p><p><b>RESULTS</b>The results of HE and Masson staining indicated that the local injection of external NGF can up-regulate bone mass, amount of bone trabecula, and bone maturity in the mouse model. The mature bone rate in treatment group of 1 week and 4 weeks after operation were significantly higher than those in the control group (P<0.05).</p><p><b>CONCLUSIONS</b>NGF can shorten the period of bone maturation.</p>

Fabrication and in vitro biological safety of a novel functional coating on microarc-oxidized titanium / 实用口腔医学杂志

Objective:To fabricate and to study the surface morphology and biological safety of a novel coating on microarc-oxidized titanium.Methods:The novel functional coating was fabricated by cross-linking the double-layer nanoparticles loading rhBMP-2 and SDF-1 with gelatin on microarc-oxidation coating on titanium implant surface.The surface topography was observed and optimized,and the biological safety of the novel coating was primarily evaluated by cell toxicity test,oral mucosa stimulation test and hemolysis test in vitro.Results:The novel functional coating possesses excellent morphology.The coating showed the cytotoxicity of score 1 and no mucous membrane irritation,the hemolytic rate of the coating was 4.6％.Conclusion:The coating possesses good morphology and biological safety.

Early Osseointegration of Implants with Cortex-like TiO2 Coatings Formed by Micro-arc Oxidation: A Histomorphometric Study in Rabbits / 华中科技大学学报（医学）（英德文版）

In our previous studies,a novel cortex-like TiO2 coating was prepared on Ti surface through micro-arc oxidation (MAO) by using sodium tetraborate as electrolyte,and the effects of the coating on cell attachment were testified.This study aimed to investigate the effects of this cortex-like MAO coating on osseointegration.A sand-blasting and acid-etching (SLA) coating that has been widely used in clinical practice served as control.Topographical and chemical characterizations were conducted by scanning electron microscopy,energy dispersive X-ray spectrometer,X-ray diffraction,contact angle meter,and step profiler.Results showed that the cortex-like coating had microslots and nanopores and it was superhydrophilic,whereas the SLA surface was hydrophobic.The roughness of MAO was similar to that of SLA.The MAO and SLA implants were implanted into the femoral condyles of New Zealand rabbits to evaluate their in-vivo performance through micro-CT,histological analysis,and fluorescent labeling at the bone-implant interface four weeks after surgery.The micro-CT showed that the bone volume ratio and mean trabecular thickness were similar between MAO and SLA groups four weeks after implantation.Histological analysis and fluorescent labeling showed no significant differences in the bone-implant contact between the MAO and SLA surfaces.It was suggested that with micro/nanostructure and superhydrophilicity,the cortex-like MAO coating causes excellent osseointegration,holding a promise of an application to implant modification.

Numerical study of effects from interference fit in titanium implants on mandibular bone remodeling / 医用生物力学

Objective To investigate stress and bone density distribution changes in the mandible due to the interference fit in titanium dental implants for mandible reconstruction, and study the influence of interference magnitudes on mandibular bone remodeling. Methods Eight interference fit models with titanium implants were established by finite element method. Bone remodeling based on strain energy density (SED) algorithm was employed to investigate changes in stress and bone density of the mandible in the models during 36 months with inference magnitude of 5%, 10%, 15%, 20%, 25%, 30%, 35% and 40%, respectively. Results When the diameter of pilot hole was larger than the internal diameter of titanium screw, the increment of interference magnitude would gradually enhance the screw fixation at the bone titanium dental implant interface. However, once the magnitude of interference exceeded 30%, the increase in interference magnitude might weaken the screw fixation due to the failure and loss of bone. Conclusions The diameter of pilot hole equal to or slightly smaller than the internal diameter of titanium screw is recommended for mandibular reconstruction.

Preparation and cytotoxicity evaluation of cobalt doped nanotubular implant coating / 实用口腔医学杂志

Objective:To prepare a kind of titanium implant doped with cobalt and to study its cytotoxicity.Methods:The surface of the titanium was anodized to form TiO2 nanotube arrays.Different amount of cobalt was doped by hydrothermal treatment,which was controlled by tuning the hydrothermal treatment duration.The cytotoxicity of the cobalt doped nanotubular implant coating on bone marrow stromal cells (BMSCs)was measured by CCK-8.Results:The nanotubular implant coating with different amount of cobalt was fabricated.The proliferation of BMSCs was inhibited by the nanotubular morphology and cobalt doping.Samples formed by hydro-thermal treatment in 0.1 M cobalt acetate showed significantly cytotoxicity.Conclusion:Hydrothermal treatment of anodized titanium is an effective way for developing novel cobalt doped nanotubular implant coating.The proper dose of cobalt doping needs to be further investigated.

Selective laser melted titanium implants: a new technique for the reconstruction of extensive zygomatic complex defects / 대한악안면성형재건외과학회지

The restoration of extensive zygomatic complex defects is a surgical challenge owing to the difficulty of accurately restoring the normal anatomy, symmetry, proper facial projection and facial width. In the present study, an extensive post-traumatic zygomatic bone defect was reconstructed using a custom-made implant that was made with a selective laser melting (SLM) technique. The computer-designed implant had the proper geometry and fit perfectly into the defect without requiring any intraoperative adjustments. A one-year follow-up revealed a stable outcome with no complications.

Investigation of anodized titanium implants coated with triterpenoids extracted from black cohosh: an animal study

PURPOSE: The purpose of this study was to evaluate bone response to anodized titanium implants coated with the extract of black cohosh, Asarum Sieboldii, and pharbitis semen. MATERIALS AND METHODS: Forty anodized titanium implants were prepared as follows: group 1 was for control; group 2 were implants soaked in a solution containing triterpenoids extracted from black cohosh for 24 hours; group 3 were implants soaked in a solution containing extracts of black cohosh and Asarum Sieboldii for 24 hours; group 4 were implants soaked in a solution containing extracts of pharbitis semen for 24 hours. The implants from these groups were randomly and surgically implanted into the tibiae of ten rabbits. After 1, 2, and 4 weeks of healing, the nondecalcified ground sections were subjected to histological observation, and the percentage of bone-to-implant contact (BIC%) was calculated. RESULTS: All groups exhibited good bone healing with the bone tissue in direct contact with the surface of the implant. Group 2 (52.44 +/- 10.98, 25.54 +/- 5.56) showed a significantly greater BIC% compared to that of group 3 (45.34 +/- 5.00, 22.24 +/- 2.20) with respect to the four consecutive threads and total length, respectively. The BIC% of group 1 (25.22 +/- 6.00) was significantly greater than that of group 3 (22.24 +/- 2.20) only for total length. CONCLUSION: This study did not show any remarkable effects of the extract of black coshosh and the other natural products on osseointegration of anodized titanium implants as coating agents. Further studies about the application method of the natural products on to the surface of implants are required.

Endosseous implantation of calcium phosphate coated titanium implant prepared via micro-arc oxidation/electrochemical deposition / 中国组织工程研究

10.3969/j.issn.2095-4344.2013.25.002

A Comparison of the Biocompatibility of Titanium-Base Alloy According to Surface Treatments / 대한정형외과연구학회지

PURPOSE: Various surface treatments are developed and adopted to get a biological fixation by the osseointegration. An anodizing treatment, used on the surface treatment of aluminium, is applied to the surface treatment of the dental implant recently. The purpose of this study was to determine the biocompatibility and osseointegration of the titanium-base alloys according to 4 different surface treatments. MATERIALS AND METHODS: Cylindrical rods were made of titanium-base alloys, and treated with machining, grit-blasted, anodizing, and plasma spray as four groups. The rods were implanted into the femur of the 8 adult dogs. Two dogs were allocated as controls. At the postoperative 1month and 9months, the histological and push-out test was done. RESULTS: No specific systemic reactions in terms of complete blood cell count, blood chemistry, urinalysis were observed. There were no tissue necrosis, foreign body reaction, and inflammatory response to the implanted rods on the histological findings. A load-displacement curve was recorded to compare an interfacial shear strength between bone and metal, the values of the grit-blasted, anodizing, and plasma-spray groups were larger than that of machining group (p0.05). CONCLUSION: The surface treatment with anodizing would be options for artificial joint because of its lower manufacturing price and excellent biomechanical and osseointegration nature.

A comparison of bone bed preparation with laser and conventional drill on the relationship between implant stability quotient (ISQ) values and implant insertion variables

PURPOSE: The aim of this study was to investigate a comparison of implant bone bed preparation with Er,Cr:YSGG laser and conventional drills on the relationship between implant stability quotient (ISQ) values and implant insertion variables. MATERIALS AND METHODS: Forty implants were inserted into two different types of pig rib bone. One group was prepared with conventional drills and a total of 20 implants were inserted into type I and type II bone. The other group was prepared with a Er,Cr:YSGG laser and a total of 20 implants were inserted into type I and type II bone. ISQ, maximum insertion torque, angular momentum, and insertion torque energy values were measured. RESULTS: The mean values for variables were significantly higher in type I bone than in type II bone (P or = .05). The ISQ values were correlated with maximum insertion torque (P < .01, r = .731), total energy (P < .01, r = .696), and angular momentum (P < .01, r = .696). CONCLUSION: Within the limitations of this study, the effects of bone bed preparation with Er,Cr:YSGG laser on the relationship between implant stability quotient (ISQ) values and implant insertion variables were comparable to those of drilling.

Large cranial bone defect reconstructed by titanium implant of CAD/CAM / 中华医学美学美容杂志

Objective To explore a method of large cranial bone defect reconstructed by titanium implant with computer aided design(CAD)/computer aided manufacture(CAM)technique.Methods From April 2006 to June 2008,7 cases of cranial bone defect due to tumor and trauma were admitted.The data of skull bone defects were obtained by CT.The resin model was designed and manufactured with rapid prototyping technique.Results The CT data could be used by image software directly.The resin model was manufactured accurately by RP technique.The titanium implant design could be completed by CAD/CAM.7 patients achieved one stage healing.After a follow-up of 6 months to 1 year,cranial bone defect was reconstructed satisfactorily.Conclusion Individual design and repair of large cranial bone defect with CAD/CAM technique is worth extending application clinically.It is a quite ideal and very simple method for the surgical treatment of the cranial bone defect.