La entrevista a agentes implicados en la actividad industrial

1_{Faculty of Dental Sciences, University of Peradeniya}

2

Department of Basic Sciences, Faculty of Dental Sciences, University of Peradeniya

3

Department of Restorative Dentistry, Faculty of Dental Sciences, University of Peradeniya

4_{Royal Oman Air Force, Masirah Air Base, Sultanate of Oman}

The study of root and canal anatomy of teeth has clinical and anthropological significance. A number of studies have shown different trends in the shape and number of roots and canals of teeth among different populations. It has been reported that the mesiobuccal root of the maxillary first molar contains a double root canal system more often than a single canal. However, prevalence of such morphological variations for South Asian people has rarely been reported. The aim of this study was to determine the root and canal morphology of permanent maxillary first molars in a Sri Lankan population with special concern to the presence of a second canal in the mesiobuccal root.

One hundred and fourteen permanent maxillary first molars were washed immediately after extraction and stored in 10% formalin until the collection was completed. The teeth were boiled in 5% NaOH for five minutes and then cleaned with 10% NaOCl to remove organic debris on the surface. Any further deposits such as calculus and bone fragments were removed by scaling and polishing. Each specimen was examined visually under a quartz-halogen light with the aid of a hand lens. The root numbers of the molars were recorded. Vacuum injection protocol was used to inject the ink into the root canal system and make the tooth transparent in order to visualize the canal system. The cleared specimens were examined under a dissecting microscope at ×10 magnification. Vertucci’s classification was taken as the main reference during the evaluation of the samples. JMP (SAS Institute, Ver. 3) software was used for statistical analysis.

The commonest canal type in the mesiobuccal root was type IV (42.11%), followed by type II (24.56%) and type I (22.81%). The prevalence of the second canal in the mesiobuccal root was 77.20% and that in distobuccal root was 3.51%. Palatal root had only a single canal in 99.12% of the teeth. These findings signify that due consideration should be given by clinicians to find the second canal in the mesiobuccal root of upper first molar for successful root canal treatment of the permanent maxillary first molar tooth..

Proceedings of the Peradeniya University Research Sessions, Sri Lanka, Vol. 16, 24th _{November 2011}

61

Effect of Root Extracts of Pongamia pinnata on Cell Surface Hydrophobicity of

Candida spp.

H.M.D.K. Kanatiwela1,2, G.J. Panagoda3, C.L. Abayasekara1 and N.K.B. Adikaram 1

1

Department of Botany, Faculty of Science, University of Peradeniya

2

Postgraduate Institute of Science, University of Peradeniya

3

Division of Microbiology, Faculty of Dental Sciences, University of Peradeniya

Candida is a dimorphic fungus that causes opportunistic infections. Cell surface

hydrophobicity (CSH) of Candida plays an important role in the pathogenecity of the organism as it is a key factor for the adhesion of the candidal cell to the host tissue. Our previous findings revealed a significant anti-candidal activity of the root extract of plant

Pongamia pinnata (“karanda”/ “pongam”) which is popular in Sri Lankan traditional

medicine. Hence, this study aimed to evaluate the effect of root extracts of P. pinnata on CSH of Candida spp.

Root extract of P. pinnata was prepared using 75% ethanol and the extract was evaporated and freeze dried. CSH of five different candidal isolates (MIC were previously determined) were evaluated under five different concentrations [Minimum Inhibitory Concentrations (MIC), 1/2 x MIC, 1/4 x MIC and 1/8 x MIC] of the freeze dried extract. Data were analysed using analysis of variance (ANOVA) and means were separated by Tukey test at P<0.05.

Among the five isolates subjected to the assay, Candida dubliniensis was the most hydrophobic followed by Candida guilliermondii. The hydrophobic affinity of Candida

albicans (ATTC 90028 and the wild type strain) and Candida parapsilosis was relatively

low. The effect of P. pinnata on the CSH was concentration dependent. C. albicans (ATCC 90028), C. albicans (wild type) and C. dubliniensis, showed a significant reduction (P<0.05) in their CSH when treated with 1/8 MIC, which was the lowest concentration used in the study. Negative CSH were observed for C. guilliermondii at 1/4 MIC, while a negative CSH was observed for the other isolates when they were treated with 1/8 MIC. Negative CSH may be an indication of the hydrophilic behavior of the organism which makes the organism less virulent.

Capability of root extract of P. pinnata to influence CSH could be due to its potential in altering the surface characteristics of the organism. Its ability to make a significant reduction in the CSH at concentrations even below the MIC will assist the control of the pathogen instead of its complete inhibition. Since Candida is a commensal fungus, usage of sub-inhibitory concentrations will help maintain the balance of the host microflora while controlling pathogenicity of the organism. However, purification of the active compound of the root extract and evaluation of its effect on CSH of Candida spp. is needed.

The results suggest that root extract of P. pinnata, has a potential in reducing CSH of Candida spp, even below their MICs. This will result a reduction in the hydrophobic binding capacity of the organism when treated with the extract.

Proceedings of the Peradeniya University Research Sessions, Sri Lanka, Vol. 16, 24th _{November 2011}

62

Association between Plasma Lipid Levels and Periodontitis: A Preliminary Analysis

W.K.L. Perera1, E.A.A.P. Amaratunga2, W.C. Mohotty1, N.P.M. Perera1, S. Kularatne3, R. Sivakanesan4 and A. Tilakaratne1

1_{Department of Oral Medicine and Periodontology, Faculty of Dental Sciences,}

University of Peradeniya

2

General Hospital, Ampara

3

School of Medicine, Griffith University, Australia

4_{Department of Biochemistry, Faculty of Medicine, University of Peradeniya}

Hyperlipidaemia and periodontitis are both highly prevalent chronic diseases in the world population, with periodontal disease being the most prevalent adult oral health problem in Sri Lanka. Literature reveals a bidirectional relationship between periodontitis and some systemic illnesses including atherosclerotic cardiovascular diseases, metabolic diseases such as diabetes mellitus and dyslipidaemia. Dyslipidaemia is an established causative factor for atherosclerosis and cardiovascular diseases. Periodontitis could alter blood lipid metabolism, however treating periodontal infections improves the dyslipideamic status in patients. The objective of this study was to evaluate any possible relationship between presence of periodontitis and blood lipid levels.

This is an ongoing study in the Division of Periodontology, Faculty of Dental Sciences, University of Peradeniya. The study consisted of a ‘Test’ group of patients (n = 47) diagnosed with periodontitis according to the established diagnostic criteria, and an age and sex matched ‘Control’ group (n = 22) with individuals free of periodontitis who attended the clinic for dental consultations. Full mouth periodontal assessments were done by a well trained practitioner, following intra-examiner calibration. Their lipid profiles were assessed within three days following recruiting subjects and prior to commencing periodontal treatment or oral prophylaxis.

Results of the preliminary analysis showed that, there were significant increases in levels of Total-Cholesterol and Low-Density Lipoprotein Cholesterol in the test group compared to the control group (p < 0.013 and p < 0.007, respectively; Students t-test). This preliminary finding supports the already reported trend by similar research studies outside Sri Lanka to describe the association of hyperlipidemia and periodontitis.

Financial assistance by University of Peradeniya (Research Grant RG/2009/40/D) is acknowledged.

Proceedings of the Peradeniya University Research Sessions, Sri Lanka, Vol. 16, 24th _{November 2011}

63

A Descriptive Study of Amelogenesis Imperfecta including Syndromic Forms