Periodontal and gingival changes amongst pregnant women in Lagos, Nigeria

Objective: To assess the periodontal and gingival changes during different stages of pregnancy among women in a Nigerian Teaching Hospital. Method : Fifty three pregnant women attending the ante-natal clinic of the Lagos University Teaching Hospital, (LUTH), were included in the study while, 53 non- pregnant with mean age 29.40 ± 3.8years, and apparently healthy women with mean age 30.96 ±2.3years served as the control. Periodontal and oral hygiene status were assessed using the Community Periodontal Index of Treatment Needs (CPITN) and the Simplified Oral Hygiene (OHI-S) Indices respectively. Result: There were a higher number of sextants with gingival bleeding and shallow pockets among the pregnant women in the 2nd and 3rd trimesters of pregnancy compared to that of the non-pregnant women. The number of sextants with gingival bleeding and shallow pocket however reduced post partum. Thus, in the pregnant women the mean number of sextants with gingival bleeding was 0.9 in 1st trimester, 1.4 in the 2nd trimester, 1.0 in the 3rd trimester and 0.1 postpartum. The mean number of sextants with pocket (code 3) was 0.1 in the 1st trimester, 0.4 in the 2nd trimester, 0.3 in the in 3rd trimester & 0.1 postpartum. Whereas in the non- pregnant group, the mean no of sextants with gingival bleeding was 0.6 at the 1st examination ,0.5 at the 2nd examination and 0.4 at the 3rd examinations and the mean number of sextants with pocket was 0.1at the 1st examination, 0.2 at the 2nd and 3rd examination. The mean OHI-S score of pregnant women increased from 2.36 ± 0.91 at the beginning of the study to 3.03±0.72 at the end of the study. While the score of the control group increased from 2.06±1.1 to 2.65±0.99. Conclusion: The OHI-S score, gingival bleeding and pockets were higher in the pregnant than in the non –pregnant women. It is suggested that pregnant women should have routine dental check-up and early management of periodontal disease through adequate plaque control

The associations of malaria parasite and ABO blood groups with aggressive periodontitis in Nigerians - a preliminary study

Objective: Aggressive Periodontitis (AgP) is a rare form of periodontitis which has been associated with aetiological factors including genetic predisposition, Aggregatibacter actinomycetemcomitans, and blood group B. It seems to have a racial predisposition being more common among blacks, particularly people of West African origin. The role of endemic factors such as malaria is yet to be investigated in AgP. The aim of this study was to explore the associations of malaria parasites and ABO blood groups with aggressive periodontitis. Method: A preliminary case-control study on localized aggressive periodontitis patients and age and gender matched controls. Microbiological and hematological tests were performed to determine the presence of malaria parasites and ABO blood groups respectively. Result: Eight LAgP patients and 9 age and gender-matched controls were seen. Six patients were positive for Plasmodium Falciparum malaria parasite, compared with 2 controls. This difference was statistically significant (p=0.044). The prevalence of malaria infection was not significantly associated with age (p = 0.44) or gender (p = 0.34) of the subjects. Conclusion: This preliminary study showed a high prevalence of malaria parasites among patients with aggressive periodontitis. Malaria infection may be associated with AgP. Studies with larger sample sizes may be needed to further investigate the relationship between aggressive periodontitis and malaria infection

Relationship of oral hygiene status and practices with oral lesions in a group of HIV positive patients in Lagos, Nigeria

Objective: The oral health of HIV positive patients may be compromised because of their depressed immunity and may increase their risk of developing some oral lesions. This study was carried out to assess the relationship of the oral hygiene status and practices with oral lesions in HIV positive patients at a dedicated HIV clinic in Nigeria. Method: A cross sectional study of adult HIV positive patients aged 18 years and above at the HIV outpatient clinic of the Lagos University Teaching Hospital. Data on age, gender, marital status, level of education and oral hygiene practices were collected. Their CD4 counts were recorded. Oral examination was carried out on all patients to assess their oral hygiene status using the Simplified Oral Hygiene Index. Oral lesions were recorded when present. Result: A total of 134 HIV positive patients were seen, most (71.6%) of whom had never visited a dentist. The mean oral hygiene index (OHI-S) score of the patients was 1.85 and 55.2% had a fair oral hygiene status. The majority (77.6%) cleaned their teeth once daily. Oral candidiasis and linear gingival erythema (LGE) were the two most prevalent oral lesions being 26.1% and 11.2% respectively. The mean oral hygiene index (OHI-S) score was higher in males [2.10] compared with females [1.71] (p<0.05), in patients who had never visited the dentist [1.99] compared with those who had visited the dentist previously [1.49] (p<0.05) and in patients with linear gingival erythema compared with those without the lesion (p< 0.05).The CD4 + Tlymphocyte count was not associated with the OHI-S (p>0.05). Conclusion: Poorer oral hygiene was significantly associated with male gender, no previous dental visits and linear gingival erythema lesions in the HIV positive patients in this study. Regular oral health education programmes should be incorporated into the treatment protocol of HIV positive patients at the HIV clinic to improve their overall health status

Diagnostic and treatment dilemma of gingival enlargement: a report of 3 cases

Gingival enlargement is a common feature of periodontal disease which is occasionally associated with medication use for systemic conditions such as hypertension and epilepsy. However, other local and systemic factors have been implicated in the aetiopathogenesis of this condition which could pose diagnostic and therapeutic challenge for clinicians. This paper presents the management of three cases of gingival enlargement recently seen at the Dental Centre of the Lagos University Teaching Hospital, Lagos. The association of unusual secondary aetiological factors is emphasized

Stabilized lasers for advanced gravitational wave detectors

Second generation gravitational wave detectors require high power lasers with more than 100 W of output power and with very low temporal and spatial fluctuations. To achieve the demanding stability levels required, low noise techniques and adequate control actuators have to be part of the high power laser design. In addition feedback control and passive noise filtering is used to reduce the fluctuations in the so-called prestabilized laser system (PSL). In this paper, we discuss the design of a 200 W PSL which is under development for the Advanced LIGO gravitational wave detector and will present the first results. The PSL noise requirements for advanced gravitational wave detectors will be discussed in general and the stabilization scheme proposed for the Advanced LIGO PSL will be described

Participatory Militias: An Analysis of an Armed Movement's Online Audience

Armed groups of civilians known as "self-defense forces" have ousted the powerful Knights Templar drug cartel from several towns in Michoacan. This militia uprising has unfolded on social media, particularly in the "VXM" ("Valor por Michoacan," Spanish for "Courage for Michoacan") Facebook page, gathering more than 170,000 fans. Previous work on the Drug War has documented the use of social media for real-time reports of violent clashes. However, VXM goes one step further by taking on a pro-militia propagandist role, engaging in two-way communication with its audience. This paper presents a descriptive analysis of VXM and its audience. We examined nine months of posts, from VXM's inception until May 2014, totaling 6,000 posts by VXM administrators and more than 108,000 comments from its audience. We describe the main conversation themes, post frequency and relationships with offline events and public figures. We also characterize the behavior of VXM's most active audience members. Our work illustrates VXM's online mobilization strategies, and how its audience takes part in defining the narrative of this armed conflict. We conclude by discussing possible applications of our findings for the design of future communication technologies.Comment: Participatory Militias: An Analysis of an Armed Movement's Online Audience. Saiph Savage, Andres Monroy-Hernandez. CSCW: ACM Conference on Computer-Supported Cooperative Work 201

Angle of Repose and Angle of Marginal Stability: Molecular Dyanmics of Granular Particles

We present an implementation of realistic static friction in molecular dynamics (MD) simulations of granular particles. In our model, to break contacts between two particles, one has to apply a finite amount of force, determined by the Coulomb criterion. Using a two dimensional model, we show that piles generated by avalanches have a {\it finite} angle of repose $\theta_R$ (finite slopes). Furthermore, these piles are stable under tilting by an angle smaller than a non-zero tilting angle $\theta_T$, showing that $\theta_R$ is different from the angle of marginal stability $\theta_{MS}$, which is the maximum angle of stable piles. These measured angles are compared to a theoretical approximation. We also measure $\theta_{MS}$ by continuously adding particles on the top of a stable pile.Comment: 14 pages, Plain Te

Stabilized high-power laser system for the gravitational wave detector advanced LIGO

An ultra-stable, high-power cw Nd:YAG laser system, developed for the ground-based gravitational wave detector Advanced LIGO (Laser Interferometer Gravitational-Wave Observatory), was comprehensively characterized. Laser power, frequency, beam pointing and beam quality were simultaneously stabilized using different active and passive schemes. The output beam, the performance of the stabilization, and the cross-coupling between different stabilization feedback control loops were characterized and found to fulfill most design requirements. The employed stabilization schemes and the achieved performance are of relevance to many high-precision optical experiments

Dynamics and stress in gravity driven granular flow

We study, using simulations, the steady-state flow of dry sand driven by gravity in two-dimensions. An investigation of the microscopic grain dynamics reveals that grains remain separated but with a power-law distribution of distances and times between collisions. While there are large random grain velocities, many of these fluctuations are correlated across the system and local rearrangements are very slow. Stresses in the system are almost entirely transfered by collisions and the structure of the stress tensor comes almost entirely from a bias in the directions in which collisions occur.Comment: 4 pages, 3 eps figures, RevTe