1,721,372 research outputs found
Management of a Fractured, Nonremovable Implant: A Clinical Report With a 12-Month Follow-Up
Full text linkAbstract
Implant failures could be due to biological or mechanical factors, which also include fracture of the fixture. The present report presents a case of a single fractured implant placed in the left mandibular molar region. Since the residual portion of the fixture was perfectly osseointegrated with no signs of peri-implantitis, and in direct contact with the roof of the inferior alveolar nerve canal, it was decided to treat the patient with a short implant positioned on top of the fractured, and not removing the fractured implant. Clinical and radiographical follow-up was performed for 12 months after loading. Periimplant soft tissues healing and implant osseointegration were achieved 6 months after implant placement; at the end of the follow-up a periimplant bone remodeling of 0.3 mm was observed. In conclusion, short implants could be taken into consideration as a treatment option in cases of nonremovable implants and sufficient residual bone height
Bilateral diffuse gingival enlargement in a patient with type 1 neurofibromatosis
No full text[No abstract available
In vitro analysis with human bone marrow stem cells on titanium disks with different surface topographies
No full textThe aim of this study was to assess how surface topography can induce osteoblast differentiation in mesenchymal stem cells by analyzing the expression levels of bone related genes and mesenchymal stem cells marker. Thirty disk-shaped, commercially pure Grade 2 titanium samples (10 x 2 mm) with 3 different surface topographies (DENTSPLY-Friadent GmbH, Mannheim, Germany) were used in the present study: 10 Ti machined disks (control), 10 Ti sandblasted and acid etched disks (DPS) and 10 sandblasted and acid etched disks at high temperature (Plus). Samples were processed for real time Reverse Transcription-Polymerase Chain Reaction (RT–PCR) analysis.
By comparing machined and Plus disks quantitative real-time RT–PCR showed a significant reduction of the bone related genes osteocalcin (BGLAP) and osteoblast transcriptional factor (RUNX2). The comparison between sandblasted and Plus disks showed a slight induction of all the genes examined (RUNX2, ALPL, COL1A1, COL3A1, ENG, FOSL1, SPP1, and SP7); only the expression of BGLAP remained stable. The present study demonstrated that implant surface topography affects osteoblast gene expression. Indeed, Plus surface produces an effect on PB-hMSCs in the late differentiation stages. The obtained results contribute to the understanding of the molecular mechanism of implant osseointegration, the molecular events related to the differentiation of stem cells into osteoblasts and as a model for comparing dental implants with different surface topography
Sinus Augmentation with Phycogene Hydroxyapatite: Histological and Histomorphometrical Results after 6 Months in Humans
No full textBone regeneration with phycogene hydroxyapatite. a pilot histological and histomorphometrical study in rabbit tibia defects
No full textBone regeneration with phycogene hydroxyapatite. a pilot histological and histomorphometrical study in rabbit tibia defect
Histological and Synchrotron Radiation-Based Computed Microtomography Study of 2 Human-Retrieved Direct Laser Metal Formed Titanium Implants
Full text linkBACKGROUND:
The macroscopic structure of bone has been traditionally studied through x-ray radiography or x-ray tomography. However, the resolution limits of these techniques do not enable the reconstruction of the composite bone architecture at the nanometer level. Compared with histomorphometry, x-ray micro-CT has shown its efficiency in providing nondestructive and rapid 3D images and measurements on bone microstructure. Micro-CT higher resolution has been achieved with synchrotron radiation-based computed microtomography (SRμCT).
PURPOSE:
The aim of this study was a histological and SRμCT analysis of 2 porous titanium implants.
MATERIALS AND METHODS:
Two direct laser metal forming titanium implants were inserted in the posterior maxilla of a patient and retrieved after 2 months. One of these implants was treated to obtain thin ground sections, whereas the other underwent a SRμCT evaluation.
RESULTS:
The histological results, showing that the implant surface presented superficial debris and particle inclusions in the surrounding tissue close to the bone area, were confirmed by micro-CT investigations.
CONCLUSIONS:
SRμCT allowed high resolution with good sample penetration and depth of focus and an evaluation of the relative arrangement of structures that cannot be determined by 2D imaging
Peri-implant bone reactions around immediately loaded conical implants with different prosthetic suprastructures: Histological and histomorphometrical study on minipigs
No full textThe aim of this study was to evaluate peri-implant bone reactions around immediately loaded conical implants with metal and acrylic resin prosthetic restorations. Five splinted conical implants were inserted in each hemimandible of six minipigs at the alveolar crest level. Ten implants were inserted in each minipig. All the implants were immediately loaded. The implants were divided into a group with an acrylic resin prosthetic restoration and into another group with a metal prosthetic restoration. No postoperative complications or deaths of the minipigs occurred. All minipigs were killed after 3 months. No implant was lost. A total of 60 implants were retrieved and processed to obtain thin ground sections. Histology and histomorphometry showed the presence of compact, mature bone around all the implants. Bone was in close contact with the implant surface starting from the first or second implant threads. A high quantity of mineralized bone was present around immediately loaded conical, root form implants. No differences in the peri-implant bone response were found in the groups with different prosthetic reconstructions. © 2009 Springer-Verlag
Regenerative properties of collagenated porcine bone grafts in human maxilla: demonstrative study of the kinetics by synchrotron radiation microtomography and light microscopy
No full textObjectives: Recently, it has been reported that heterologous biomaterials, where the collagen matrix is preserved, seem to facilitate blood clotting and the subsequent invasion of repairing and regenerative cells. This study aimed at evaluating the healing of human extraction sockets grafted with a collagenated cortico-cancellous porcine bone (mp3®, OsteoBiol®, Tecnoss®, Giaveno, Italy) by Synchrotron Radiation X-ray microtomography (microCT) and histology in order to have a 3D quantitative characterization over time.
Materials and Methods: Ridge preservation with porcine bone and collagen membrane was performed on 21 patients using a flapless approach and a secondary soft tissue closure. At the time of implant placement, 6 bone samples were harvested, two in the 3-month group, two in the 6-month group, one in the 12-month group post-surgery, and evaluated by microCT and histology.
Results: MicroCT revealed that in the grafted sites there was a greater number of trabeculae, although they appeared thinner than in the control sites (spontaneously healed sockets); these trabeculae homogenously filled the defects, suggesting an improved strength of the socket. Histology showed that over time the amount of biomaterial decreased and the newly formed bone increased, whilst less dense bone with wider marrow spaces was detected in the control sample, supporting Synchrotron findings.
Conclusions: The morphometric data converge to indicate the suitability of porcine bone for the preservation of post-extraction sockets.
Clinical Relevance: The use of mp3 is encouraged to preserve and heal sockets
A Histomorphometric Comparison of Anorganic Bovine Bone (ABB) and Calcium Sulphate (CaS) Used in Sinus Augmentation Procedures: A Study in Sheep
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