1,721,008 research outputs found
Fracture toughness of a new generation of hybrid glass ceramic. the zi1conia rbnforced uthium siucate ceramic (ZLS)
No full textImmediate denture fabrication: a clinical report.
No full textThe aim of the present clinical report was to describe the use of a patient’s extensive fixed prosthesis, where the supporting teeth were hopeless, for fabricating an interim immediate complete denture. The present procedure was used to replicate the vertical dimension, phonetic and aesthetic of the existing fixed prostheses as part of an immediate denture and a final complete denture
Descriptive histological evaluation of bone regenerated around three different bone-substitute materials after sinus augmentation in humans
No full textThe relationship between time of re-tightening and preload loss of abutment screws for two different implant designs: an in-vitro study
No full textThe loosening of an abutment screw is one of the most frequent complications in implant-prosthetic rehabilitation, especially for single-crown cemented prostheses. This complication is due to several mechanical factors including type of connection, abutment-screw geometry, settling effects, and cyclical load. The purpose of the present in vitro study was to compare and associate different times of retightening with reductions in preload losses. We evaluated 40 internal hexagon dental implants and 40 external hexagon dental implants, with their related abutment screws. The implants were embedded in acrylic resin in cylindrical polyvinyl chloride tubes (26 mm diameter, 20 mm height). The abutments were fixed to the implants with screws to an initial torque of 35 Ncm using a digital torque meter with decimal precision. Two different types of connection were randomly divided in 4 subgroups of 10 samples each. One subgroup was used as control. The test groups underwent retightening to the same initial torque at increasing times from initial torque application for tightening of the abutment screws, to their retightening at 2 minutes, 5 minutes, and 10 minutes. The retightening time of 2 minutes shows significantly reduced preload loss. Randomized clinical trials are strongly required to provide clinicians with a beneficial standardized protocol of retightening that can be applied in routine clinical practice
Knife-tooth edge preparation: does the clinical outcome reflect hystological perspective?
No full textComparison of the primary stabilities of conical and cylindrical endosseous dental implants: an in-vitro study
No full textThe aim of this study is to determine the differences in primary stability between conical and cylindrical dental implants. The insertion and removal torques were the parameters used to measure the primary stability of the implants. Ten conical and cylindrical dental implants were positioned in polyurethane foam blocks to simulate bone density classes D1, D2, D3 and D4. The insertion and removal torques were quantified using a digital torque gauge. The maximum insertion torque and the maximum removal torque measured for the D1 and D4 synthetic bone were significantly higher for the conical implants than the cylindrical implants. In this in-vitro model, conical implants show significantly higher primary stability than cylindrical implants for the D1 and D4 synthetic bone classes
Human Histological evaluation of a new dental implant multisurface topography after four and eight weeks of healing on .
No full textAim:,
It has been demonstrated that the undersized osteotomy could improve the osseointegration process. To the author best knowledge there is no data in the literature treating the bone healing near dental implants with a multisurface topography using this protocol.
The present study aimed to histologically evaluate the performance of a new multisurface topography dental implant placed in humans after four and eight weeks of healing.
Materials and Methods:
Histological evaluation was performed on two multisurface topography dental implants of 4/3 x 10 mm inserted with a torque of 70 ± 10 Ncm. Both implants were retrieved through patients’ request to remove them due to “feeling of foreign body presence in their jaw”. Notwithstanding the patients were discouraged and informed about the risks of implants removal they insisted on their decision. However before removing, the patients agreed to sign an information consent form on the retrieved implants to be included in a study. One implant was retrieved after four weeks of healing while the other was retrieved eight weeks after. Both specimens were fixed in 10% buffered formalin at pH 7.1, dehydrated in an ascending series of alcohol rinsed and embedded in a glycolmethacrylate resin. After polymerization, the specimens were sectioned, along their longitudinal axis, with a high-precision diamond disc at about 80 μm, and ground down to about 30 μm with a custom built sawing and grinding apparatus. The evaluation was performed under brightfield light microscope, confocal scanning laser microscope (CSLM), and a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX).
Results: Histological findings showed after 4 weeks a BIC rate of 42.7 % with a high level of cellular activity near the implant surface associated to areas of newly formed bone. SEM evaluation showed osteoid seems directly laid-down over the implant surface. After 8 weeks the BIC rate was of 60.1 % with some area of bone remodelling process in action. The EDX investigation measured as weight % in five areas of each sample showed a Ca/P ratio of 0.9 ± 1.2% for implant retrieved after four weeks and 1.3 ± 0.2% for implant retrieved after eight weeks.
Conclusions: The histological results demonstrated that the new multisurface topography dental implants, when placed in undersized osteotomy sites, showed an adequate bone healing after only four weeks (42.7% of BIC). Moreover, EDX investigation demonstrate a predominance of immature bone matrix under mineralization process
Vascular network organization in posterior atrophic human mandible: a guide for an appropriate surgical approach
No full textBackground: The bone vascularity plays a key role for a successful surgical approach during implant placement on the posterior
atrophic lower jawbone. Although, some very old references are reported on animal studies, to the author best knowledge no
data are present in literature regarding this subject.
Aim/Hypothesis: The aim of this work was to evaluate the vascular arrangement in posterior, edentulous, atrophic mandibular
crests on humans
Evaluation of Fibrin Clot Attachment on Titanium Laser-Conditioned Surface Using Scanning Electron Microscopy
No full textThe study aimed to evaluate the effects of different titanium surface treatments on blood clot extension (bce)
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