1,721,002 research outputs found
Consensus conference on immediate loading: the single tooth and partial edentulous areas.
No full textClear cell odontogenic carcinoma.report of a case with lymph node and pulmonary metastases.
No full textThe authors present a case of a rare type of odontogenic tumour, recently described as 'clear cell odontogenic tumour'. The patient died 5 years after the initial diagnosis with lymph node and diffuse pulmonary metastases. This fact can support the view that this tumour, histologically characterised by the presence of cells with a clear cytoplasm, can behave in an aggressive way and has true metastatic potential, despite the absence of malignant cellular features
Immediately loaded FBR-coated Pitt-Easy Bio-Oss implants. A histologic evaluation in 3 patients after 8-12 weeks of function
No full textClodronate combined with a surfactant (Tween 20) does not improve osseointegration: a rabbit immunohistomorphometric study.
No full textAbstract
Biphosphonates are compounds that inhibit bone reabsorption mediated by osteoclasts or the progression of periodontal disease independent on the host response to pathogenic bacteria that colonize the tooth surface. The use of biphosphonates in oral implantology is still in the experimental stage. The aim of this study is to evaluate the efficacy of a non-aminobiphosphonate combined with a surfactant to increase the ability of the drug to link to the implant and bone surfaces in the development of osseointegration in rabbits. Smooth titanium implants were devised to be used on rabbit femurs. A topical administration of clodronate combined with the surfactant (Tween 20) at different concentrations was made on the implant surface and in the implant site to increase the bone and implant adhesiveness. Placebo was given to the control group. New Zealand rabbits were used and sacrificed by CO2 after 8 weeks from the implantations. A histologic and histomorphometric analysis was carried out. Results did not show significant difference between the tests and the placebo groups. Our data are different from other similar studies obtaining statistically significant differences. These differences could depend on the efficacy of the drug used and on the procedure of application of the drug on the implant. This study demonstrates poor efficacy of clodronate applied topically to the implant and implant site during surgery to increase the percentage of osseointegration in the implant. Further studies using different fixation techniques of the drug may be necessary to confirm the present data
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
The Effects of High Insertion Torque Versus Low Insertion Torque on Marginal Bone Resorption and Implant Failure Rates: A Systematic Review With Meta-Analyses
No full textOBJECTIVES: The aim was to analyze the data about the effects on marginal bone
resorption and implant failure rates between implants inserted with high or low
insertion torque values.
MATERIALS AND METHODS: A systematic literature search until July 2015 was
conducted. Data were summarized qualitatively in descriptive tables and
quantitatively by performing random effects meta-analyses of effect sizes (ESs)
for bone resorption and bone-to-implant contact (BIC) and relative risks (RRs)
for implant failures. Risk of bias assessments were performed using the Cochrane
tool for human studies and the SYRCLE's tool for animal studies.
RESULTS: Four studies in humans and 6 quasirandomized animal studies were
included. A total of 591 implants were evaluated qualitatively: 348 installed
with high insertion torque (>25 Ncm, up to 176 Ncm) and 243 implants inserted
with low torque values (<30-35 Ncm). No significant differences were detected for
bone resorption (ES, 0.13; 95% confidence interval [CI], -0.12 to 0.38 in human
studies; ES predictive interval from 35.03 to 34.50 in animal studies), implant
failure (RR, 0.39; 95% CI, 0.01-20.77 in human studies; RR, 2.05; 95% CI,
0.19-21.71 in animal studies), or BIC (ES predictive interval from -3.84 to 5.13
in animal studies).
CONCLUSION: The current review indicated that there is no significant difference
in marginal bone resorption and implant failure rate between implants inserted
with high or low insertion torque values
Phosphatic ceramic systems in contact with bone tissue: biochemical links and reabsorblility degree on granules
No full textHigh Versus Low Implant Insertion Torque: A Histologic, Histomorphometric, and Biomechanical Study in the Sheep Mandible
No full textThe purpose of this study was to analyze, in an animal model, the histologic and biomechanical phenomena at the bone-implant interface of implants inserted with high torque (HT) as compared to low torque (LT) during the first 6 weeks of healing. Forty tapered-screw-form implants were placed in five hybrid sheep. The implant sites were placed in the mandible, using an extraoral approach; four were placed with HT (test: mean 110 Ncm) on one side and four were placed with LT (control: mean 10 Ncm) on the contralateral side. After 1, 2, 3, 4, and 6 weeks of healing, removal torque testing and resonance frequency analysis were performed and the animals were sacrificed for histologic examination. Implants from the HT group showed significantly higher bone apposition than implants from the LT group at all examined healing times. Similarly, removal torque was consistently higher for the HT as compared to the LT group. A significant loss of primary stability in the HT group was evident 7 days after placement. Implants from the LT group achieved a significant increase in stability after 4 weeks. Resonance frequency analysis was unable to detect these histologic and biomechanical modifications of the bone-implant complex. The results of the study showed that high implant insertion torque in dense cortical bone does not induce bone necrosis or implant failure, but it does increase the primary stability of implants, which is extremely important in immediate loading protocols
Histologic and Biomechanical Evaluation of the Effects of Implant Insertion Torque on Peri-Implant bone Healing
No full textVedasi l'allegat
Bone loss around immediately loaded transitional implants: histologic and microcomputed tomographic analysis – a case report
No full textImmediate loading of dental implants can significantly decrease treatment time
and thus result in an increase in patient acceptance. However, there is still a need
to investigate whether an implant in which primary stability is achieved can be
immediately loaded without the formation of connective fibrous tissue at the interface.
Three transitional implants were placed in an edentulous mandible: two implants
loaded immediately and one left unloaded. All transitional implants were retrieved
after a period of 12 weeks to perform qualitative and quantitative analysis of the
peri-implant tissue and bone-implant interface. Bone biopsy specimens containing
the transitional implant were analyzed using microcomputed tomography (micro-
CT). Subsequently, the same samples were analyzed using standard undecalcified
histology. Micro-CT analysis showed that bone tissue was slightly detached from
the surface of the loaded implant. Histology demonstrated the presence of a soft
tissue layer inside the socket. Morphometric values of total bone volume, boneimplant
contact, and bone connectivity were higher for the unloaded implant, which
appeared to be covered by an almost continuous layer of bone. Micro-CT evaluation
of some morphometric parameters and histologic results pertaining to small-diameter
transitional implants showed that uncontrolled loading may produce untoward effects
on peri-implant bone healing
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