7,314 research outputs found
Implant survival and success rates in patients with risk factors: results from a long-term retrospective study with a 10 to 18 years follow-up
OBJECTIVE:
Risk factors for implant therapy are represented by all general and local conditions that through various mechanisms can increase either short-term and long-term failure risk. The aim of this study is to assess the implant survival and implant success rates with single and multiple risk factors.
PATIENTS AND METHODS:
To address the research purpose, a retrospective cohort study was designed and implemented, including a sample of 225 patients with a total of 871 implants placed. The following risk factors were considered: smoking, bruxism, bone augmentation procedures and the presence of load risk (implants with crown/implant relation > 0.8; angulation > 25°; presence of cantilever). Follow-up ranged from 10 years to 18 years (average follow-up 13.6 years). Failures were subdivided into short-term failures, before the prosthetic phase, and long-term failures, after definitive prosthesis. The success criteria published by Albrektsson and Zarb were adopted. A Cox proportional hazard regression model was used to calculate hazard ratio, with a statistically significant p-value <0.05.
RESULTS:
Out of the 871 implants placed, 138 did not meet the success criteria, (success rate 84.16%), sixty (43.47%) were classified as "early failure" and seventy-eight as "late failure" (56.53%). A total of 70 dental implants were removed, with a survival rate of 91.96%.
CONCLUSIONS:
The presence of a single risk factor does not imply a marked increase of failure risk. Among the analyzed factors, the one that proved to be the most dangerous was bruxism, even when presented as the only risk factor. Bruxism with load risk proved to be the most dangerous association (success rate 69.23%) and could be included among the absolute contraindications for implant treatment
A randomized clinical trial about presence of pathogenic microflora and risk of peri-implantitis: comparison of two different types of implant-abutment connections
OBJECTIVE:
The aim of this in vivo study was to evaluate two different types of implant-abutment connections: screwed connection and cemented connection, analyzing peri-implant bacteria microflora as well as other clinical parameters.
PATIENTS AND METHODS:
Twenty implants were selected, inserted in 20 patients, 10 with a screwed implant-abutment connection (Group 1) and 10 with a cemented implant-abutment connection (Group 2). The peri-implant microflora was collected, after at least 360 days from the prosthetic rehabilitation, using paper points inserted in peri-implant sulcus for 30 s. Polymerase chain reaction (PCR) Real-time analyzed the presence of 9 bacteria periodontal-pathogens and Candida albicans.
RESULTS:
Our findings showed that bacteria colonized all Groups analyzed, the average bacterial count was 3.7 E +08 (±1.19) in Group 1, compared to 2.1 E +08 (±0.16) in Group 2; no statistically significant differences were observed (p>0.0.5). In Group 1, however, bacterial colonization of peri-implant sulci was over the pathogenic threshold for 5 bacteria, indicating a high-risk of peri-implantitis. Also in Group 2, results showed a microflora composed by all bacteria analyzed but, in this case, bacterial colonization of peri-implant sulci was over the pathogenic threshold for only 1 bacterium, indicating a lower risk of peri-implantitis. Moreover, clinical parameters (PPD > 3 mm and m SBI > 0) confirmed a greater risk of peri-implantitis in Group 1 compared to Group 2 (p<0.05).
CONCLUSIONS:
We concluded that, also after only 360 days, implants with screwed connection showed a higher risk of peri-implantitis that implants with cemented connection
Monolithic zirconia and digital impression: case report
The aim of this study is to present a clinical case of a full arch prosthetic rehabilitation on natural teeth, combining both digital work-flow and monolithic zirconi
Confocal laser scanning microscope, raman microscopy and western blotting to evaluate inflammatory response after myocardial infarction
Cardiac muscle necrosis is associated with inflammatory cascade that clears the infarct from dead
cells and matrix debris, and then replaces the damaged tissue with scar, through three overlapping phases: the
inflammatory phase, the proliferative phase and the maturation phase.
Western blotting, laser confocal microscopy, Raman microscopy are valuable tools for studying the inflammatory
response following myocardial infarction both humoral and cellular phase, allowing the identification and
semiquantitative analysis of proteins produced during the inflammatory cascade activation and the topographical distribution
and expression of proteins and cells involved in myocardial inflammation. Confocal laser scanning microscopy
(CLSM) is a relatively new technique for microscopic imaging, that allows greater resolution, optical sectioning of the
sample and three-dimensional reconstruction of the same sample. Western blotting used to detect the presence of a specific
protein with antibody-antigen interaction in the midst of a complex protein mixture extracted from cells, produced
semi-quantitative data quite easy to interpret. Confocal Raman microscopy combines the three-dimensional optical resolution
of confocal microscopy and the sensitivity to molecular vibrations, which characterizes Raman spectroscopy.
The combined use of western blotting and confocal microscope allows detecting the presence of proteins in the sample
and trying to observe the exact location within the tissue, or the topographical distribution of the same. Once demonstrated
the presence of proteins (cytokines, chemokines, etc.) is important to know the topographical distribution, obtaining in this
way additional information regarding the extension of the inflammatory process in function of the time stayed from the
time of myocardial infarction. These methods may be useful to study and define the expression of a wide range of inflammatory
mediators at several different timepoints providing a more detailed analysis of the time course of the infarct
Cost and Schedule Monitoring of Industrial Building Projects : Case Study
Performance measurement is a helpful tool for taking corrective actions and controlling a project as far as this enables accurate time and cost forecasts during the first stages of the construction effort when the management team still has opportunities to make adjustments. This paper overcomes the dilemma of practicability and predictability of traditional estimates at completion based on early progress measurement by presenting the empirical results from the construction project of an industrial facility. The case may be a reference practice for assessing time and cost performance measurement of any building, whose layout can be reasonably partitioned into repeatable portions. In such circumstances, an effectively-managed traditional earned value method and appropriate metrics for computing performance provide project managers with accurate forecasts as useful tools for successful project management and contro
Histological and immunohistochemical evaluation of mandibular bone tissue regeneration
The purpose of the study was to perform an immunohistochemical and histological evaluation of samples taken from different bone regeneration procedures in atrophic human mandible. 30 patients (15 men and 15 women, age range of 35-60 years), non-smokers, with good general and oral health were recruited in this study and divided into three groups. The first group included patients who were treated with blood Concentration Growth Factors (bCGF), the second group included patients who were treated with a mixture of bCGF and autologous bone, while the third group of patients was treated with bCGF and tricalcium phosphate/hydroxyapatite (TCP-HA). Six months after the regenerative procedures, all patients undergone implant surgery, and a bone biopsy was carried out in the site of implant insertion. Each sample was histologically and immunohistochemically examined. Histological evaluation showed a complete bone formation for group II, partial ossification for group I, and moderate ossification for group III. Immunohistochemical analysis demonstrated a statistically significant difference between the three groups, and the best clinical result was obtained with a mixture of bCGF and autologous bone
Combined NMDA Inhibitor Use in a Patient With Multisubstance-induced Psychotic Disorder
This document is an Accepted Manuscript reprinted from Journal of Addiction Medicine, Vol. 12 (3): 247-251, May 2018, with permission of Kluwer Law International. Under embargo until 1 May 2019. The Version of Record is available online at DOI: https://doi.org/10.1097/ADM.0000000000000390: Novel psychoactive substance use is a major social concern. Their use may elicit or uncover unpredictably as yet undescribed clinical pictures. We aimed to illustrate a multisubstance use case indistinguishable from paranoid schizophrenia, so to alert clinicians on possibly misdiagnosing substance-induced psychotic disorders. CASE REPORT: We describe a case of a 32-year-old man who started at 18 years with cannabinoids and ketamine, and is currently using N-methyl-D-aspartate (NMDA) antagonists. At age 23, he developed social withdrawal after being assaulted by a stranger, but did not consult psychiatrists until age 26; during this period, he was using internet-purchased methoxetamine and ketamine, and was persecutory, irritable, suspicious, and insomniac and discontinued all received medical prescriptions. He added dextromethorphan to his list of used substances. At age 31, while using phencyclidine, and, for the first time, methoxphenidine, he developed a religious delusion, involving God calling him to reach Him, and the near-death experiences ensured by NMDA antagonists backed his purpose. He received Diagnostic and Statistical Manual of Mental Disorders, 5th Edition diagnosis of multisubstance-induced psychotic disorder and was hospitalized 8 times, 6 of which after visiting the emergency room due to the development of extreme anguish, verbal and physical aggression, and paranoia. He reportedly used methoxphenidine, methoxyphencyclidine, ethylnorketamine, norketamine, and deschlorketamine, to achieve near-death experiences, and eventually to reach God in heavens. CONCLUSIONS: This case points to the need for better control of drugs sold on the internet. It also illustrates that people using NMDA antagonists may present clinical pictures indistinguishable from those of major psychoses and are likely to be misdiagnosed.Peer reviewe
Refined Algebraic Quantization in the oscillator representation of SL(2,R)
We investigate Refined Algebraic Quantization (RAQ) with group averaging in a
constrained Hamiltonian system with unreduced phase space T^*R^4 and gauge
group SL(2,R). The reduced phase space M is connected and contains four
mutually disconnected `regular' sectors with topology R x S^1, but these
sectors are connected to each other through an exceptional set where M is not a
manifold and where M has non-Hausdorff topology. The RAQ physical Hilbert space
H_{phys} decomposes as H_{phys} = (direct sum of) H_i, where the four subspaces
H_i naturally correspond to the four regular sectors of M. The RAQ observable
algebra A_{obs}, represented on H_{phys}, contains natural subalgebras
represented on each H_i. The group averaging takes place in the oscillator
representation of SL(2,R) on L^2(R^{2,2}), and ensuring convergence requires a
subtle choice for the test state space: the classical analogue of this choice
is to excise from M the exceptional set while nevertheless retaining
information about the connections between the regular sectors. A quantum theory
with the Hilbert space H_{phys} and a finitely-generated observable subalgebra
of A_{obs} is recovered through both Ashtekar's Algebraic Quantization and
Isham's group theoretic quantization.Comment: 30 pages, REVTeX v3.1 with amsfonts. (v4: Published version.
Keraring intrastromal segment depth measured by spectral-domain optical coherence tomography in eyes with keratoconus
On Unconditionally Secure Distributed Oblivious Transfer.
This paper is about the Oblivious Transfer in the distributed model proposed by M.
Naor and B. Pinkas. In this setting a Sender has n secrets and a Receiver is interested
in one of them. During a set up phase, the Sender gives information about the secrets to
m Servers. Afterwards, in a recovering phase, the Receiver can compute the secret she
wishes by interacting with any k of them. More precisely, from the answers received she
computes the secret in which she is interested but she gets no information on the others
and, at the same time, any coalition of k − 1 Servers can neither compute any secret nor
figure out which one the Receiver has recovered.
We present an analysis and new results holding for this model: lower bounds on
the resources required to implement such a scheme (i.e., randomness, memory storage,
communication complexity); some impossibility results for one-round distributed oblivi-
ous transfer protocols; two polynomial-based constructions implementing 1-out-of-n dis-
tributed oblivious transfer, which generalize and strengthen the two constructions for
1-out-of-2 given by Naor and Pinkas; as well as new one-round and two-round distributed
oblivious transfer protocols, both for threshold and general access structures on the set
of Servers, which are optimal with respect to some of the given bounds. Most of these
constructions are basically combinatorial in nature
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