225 research outputs found
Clinical management of a peri-implant giant cell granuloma
Purpose. Implant therapy plays an important role in contemporary dentistry with high rates of long-term success. However, in recent years, the incidence of peri-implantitis and implant failures has significantly increased. The peripheral giant cell granuloma (PGCG) rarely occurs in peri-implant tissues and it is clinically comparable to the lesions associated with natural teeth. Therefore, the study of possible diseases associated with dental implants plays an important role in order to be able to diagnose and treat these conditions. Materials and Methods. This report described a 60-year-old Caucasian male who presented a reddish-purple pedunculated mass, of about 2 cm in diameter, associated with a dental implant and the adjacent natural tooth. Results. An excisional biopsy was performed and the dental implant was not removed. Histological examination provided the diagnosis of PGCG. After 19-month follow-up, there were no signs of recurrence of peri-implantitis around the implant. Conclusion. The correct diagnosis and appropriate surgical treatment of peri-implant giant cell granuloma are very important for a proper management of the lesion in order to preserve the implant prosthetic rehabilitation and prevent recurrences
Childhood overweight-obesity and periodontal diseases: is there a real correlation?
Objective. The association between obesity and periodontitis has been extensively investigated in adults but not in young people. The aim of this study was to examine the association between overweight-obesity and periodontal disease in pediatric subjects.
Methods. Controlled cross-sectional study involving 100 school children of both gender (50 M and 50 F) between 7 and 12 years of age (mean age 9,19 +/- 1,57). Two groups were formed based on Body Mass Index value: test group with BMI >= 25 Kg/m(2) and control group with BMI <= 24 Kg/m(2). Diet intake and oral hygiene habits were recorded by a specific questionnaire and the periodontal clinical parameters were evaluated.
Results. The periodontal examination in the control group revealed a full-mouth plaque score (FMPS) value equal to 21.86% against 50.08% in the group of patients overweight/obese; the full-mouth bleeding score (FMBS) in the control group amounted to 12.7% against 26.24% of test group. No patient in either group included in the study presented a probing pocket depth (PPD) >= 3, so a significant difference regarding this value was not found. Regarding the frequency and quantity of food consumption, the number of obese patients who did not follow a balanced diet largely exceeded the number of normal-weight patients (70 versus 20%).
Conclusions. These results focus the attention on the negative impact of obesity on gingival health in young subjects, probably due to a combination of metabolic and inflammatory profiles and the result of a careless attitude towards prevention diseases of the oral cavit
Asymmetry at LHC for an U(1)' anomalous extension of MSSM
The measurement of the forward-backward asymmetry at LHC could be an
important instrument to pinpoint the features of extra neutral gauge particles
obtained by an extension of the gauge symmetry group of the standard model. For
definitiveness, in this work we consider an extension of the gauge group of the
Minimal Supersymmetric Standard Model by an extra anomalous U(1) gauge symmetry
(MiAUMSSM). We focus on pp -> e+e- at LHC and use four different definitions of
the asymmetry obtained implementing four different cuts on the directions and
momenta of the final states of our process of interest. The calculations are
performed without imposing constraints on the charges of the extra Z's of our
model, since the anomaly is cancelled by a Green-Schwarz type mechanism. Our
final result is a fit of our data with a polynomial in the charges from which
to extract the values of the charges given the experimental result.Comment: 10 pages, 12 figure
Potential use of human periapical cyst-mesenchymal stem cells (hPCy-MSCs) as a novel stem cell source for regenerative medicine applications
Mesenchymal stem cells (MSCs) are attracting growing interest by the scientific community due to their huge regenerative potential. Thus, the plasticity of MSCs strongly suggests the utilization of these cells for regenerative medicine applications. The main issue about the clinical use of MSCs is related to the complex way to obtain them from healthy tissues; this topic has encouraged scientists to search for novel and more advantageous sources of these cells in easily accessible tissues. The oral cavity hosts several cell populations expressing mesenchymal stem cell like-features, furthermore, the access to oral and dental tissues is simple and isolation of cells is very efficient. Thus, oral-derived stem cells are highly attractive for clinical purposes. In this context, human periapical cyst mesenchymal stem cells (hPCy-MSCs) exhibit characteristics similar to other dental-derived MSCs, including their extensive proliferative potential, cell surface marker profile and the ability to differentiate into various cell types such as osteoblasts, adipocytes and neurons. Importantly, hPCy-MSCs are easily collected from the surgically removed periapical cysts; this reusing of biological waste guarantees a smart source of stem cells without any impact on the surrounding healthy tissues. In this review, we report the most interesting research topics related to hPCy-MSCs with a newsworthy discussion about the future insights. This newly discovered cell population exhibits interesting and valuable potentialities that could be of high impact in the future regenerative medicine applications
On a Stackelberg Subset Sum Game
This contribution deals with a two-level discrete decision problem, a
so-called Stackelberg strategic game: A Subset Sum setting is addressed with a
set of items with given integer weights. One distinguished player, the
leader, may alter the weights of the items in a given subset , and
a second player, the follower, selects a solution in order to
utilize a bounded resource in the best possible way. Finally, the leader
receives a payoff from those items of its subset that were included in the
overall solution , chosen by the follower. We assume that the follower
applies a publicly known, simple, heuristic algorithm to determine its solution
set, which avoids having to solve NP-hard problems.
Two variants of the problem are considered, depending on whether the leader
is able to control (i.e., change) the weights of its items (i) in the objective
function or (ii) in the bounded resource constraint. The leader's objective is
the maximization of the overall weight reduction, for the first variant, or the
maximization of the weight increase for the latter one. In both variants there
is a trade-off for each item between the contribution value to the leader's
objective and the chance of being included in the follower's solution set.
We analyze the leader's pricing problem for a natural greedy strategy of the
follower and discuss the complexity of the corresponding problems. We show that
setting the optimal weight values for the leader is, in general, NP-hard. It is
even NP-hard to provide a solution within a constant factor of the best
possible solution. Exact algorithms, based on dynamic programming and running
in pseudopolynomial time, are provided. The additional cases, in which the
follower faces a continuous (linear relaxation) version of the above problems,
are shown to be straightforward to solve.Comment: 13 pages, 1 figur
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