El tratamiento de la información cualitativa

Department of Oral Pathology, Faculty of Dental Sciences, University of Peradeniya

More than 50% of patients with squamous cell carcinoma of the oral cavity have lymph node metastases and histological confirmation of metastatic disease is considered the most important prognostic factor. Among the patients with a clinically negative neck, the incidence of occult metastases varies with the site, size and thickness of the primary tumour. The TNM (Tumour/ Node/ Metastasis) staging system allows clinicians to categorise tumours of the head and neck region to assist with the assessment of disease status, management and prognosis. Management of clinically negative neck is debatable in patients with oral squamous cell carcinoma (OSCC). Although various therapeutic approaches are available, the data supporting any particular strategy do not appear to be consistent.

The stage of oral cancer is one of the main prognostic indicators. The main aim of this study was to evaluate the relationship between stage of tumour and the level of nodal metastasis and to analyse the relationship between primary site, pattern of invasion and extra capsular spread with the stage of tumour.

During the study period of 1999-2008, 292 patients of OSCC with neck dissections were included in the study. Clinical details including the clinical stage of the tumour and histopathological features such as level of differentiation, nodal status and pattern of invasion were assessed. The M: F ratio was 2.8:1. The age ranged from 24 to 86 years (mean age of 57.8±9.98 SD years). The commonest primary site was buccal mucosa followed by tongue. There were 123, 144 and 25 cases of well differentiated, moderately differentiated and poorly differentiated cancers, respectively. Of the 292 patients, 110 cases showed microscopically positive nodes and 80 of them showed extracapsular invasion. Almost all stage 1 and 2 tumours showed negative nodes and all cases of stage 3 and stage 4 tumours showed lymph node metastasis and this association was statistically significant for each site (P < 0.001; chi-square test). There was a significant association between the stage of the tumour and extracapsular invasion (P < 0.001; chi-square test). Pattern of invasion was another reproducible prognostic marker which showed a significant relationship with metastasis and extracapsular invasion (P < 0.001, chi-square test).

In conclusion, the present study provides valuable information with regard to treatment plan for patients with clinical stage 1 and 2 tumours (T1N0, T2N0). Tumours with stage 3 and 4 with pattern of invasion III or IV appears to be reliable predictors of metastasis and can be used as a tool to decide management of neck nodes. Therefore, clinical stage of the tumour should be regarded as a key factor in deciding the treatment of neck nodes in OSCC.

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

66

Oro-Facial Features, Related Medical Problems and the Level of Dental Caries in a Group of Children with Down Syndrome

E.M.S.A. Edirisooriya, R.L. Wijeyeweera, and E.M.U.C.K. Herath

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

Down Syndrome (DS) is a genetic disorder with severe growth and intellectual impairment, which results from the presence of an extra chromosome 21. Although genetic disorders are rare, DS is relatively common with an incidence of 1:700 to 1:1000. Among the range of clinical manifestations, which depend on the variable expression of the genetic mutation, some features are characteristic to DS. A majority of these appear in the oro-facial region either extra-orally such as narrow palpebral fissures or intra-orally such as macroglossia.

Children with DS belong to a large group of patients who need special dental care. This is not only due to their apparent inability to comprehend, but also due to other complications such as cardiac pathologies and impaired immunity, which have serious implications to the choice and execution of treatment. Dental caries incidence was earlier reported to be less in children with DS compared to that of healthy children. This has been attributed to the spacing between teeth and increased salivary Immunoglobulin A levels. Contrary findings have been reported in a more recent study that discovered the level of dental caries of DS children to be higher compared to that of normal children.

The main objectives of this study were to assess the level of dental caries and other intra-oral features, and the common medical problems of DS children and to assess the association of three of the known risk factors for development of DS, i.e., advanced maternal age, having a sibling with DS and consanguineously married parents. This study group consisted of all children with DS, from two special schools in the Kandy district, who met specific selection criteria. The data were collected using cross calibrated examiners after acquiring written proxy consents from parents. Subsequently, results were presented using descriptive statistics.

From the sample, 88% of children had at least one tooth with caries. This is in agreement with current trends in caries patterns that had been observed in DS children. DMFT and dmft indices were 3.25 and 6.7, respectively and were clearly high, compared to those of normal children which were 0.9 and 3.5, respectively (National Oral Health survey 2003). High percentage of children with untreated caries also indicates less attention to dental care of this group of children. Congenital cardiac or thyroid problems were observed in approximately 50% of the sample and all the participating children demonstrated macroglossia or ‘relative macroglossia’. Seventy perecent of DS children in this sample were born to mothers who were over 35 years of age, and only 8% were from consanguineously married parents.

Higher DMFT and dmft values and high occurrence of medical problems in DS children demand early intervention for prevention of dental caries and special precautions in management procedures.

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

67

A Survey on Tobacco Use and Awareness on Tobacco Related Health Hazards among Teenage Students

B.M.H.S.K. Banneheka1, M.S.M. Kularatne2 and W.M. Tilakaratne1

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

2

Ministry of Health, Sri Lanka

According to the World Health Organization (WHO), tobacco use is one of the major preventable causes of premature deaths and disease in the world. In Sri Lanka, tobacco is consumed in two forms: smoking and chewing. Chewing tobacco is used mainly as a complement to betel chewing. Smoking is mainly practiced in the form of cigarettes, beedi, and cigars. The aim of this study was to identify the tobacco habits and awareness on tobacco related health hazards in school children of 15-18 years of age.

A group of 763 students (290 males and 473 females), aged between 15-18 years, studying in randomly selected schools from the Theldeniya education zone participated in the study. Data was collected using a self administered questionnaire with both open ended and multiple choice type questions.

Among the sample, 20.8% (159 students) had used tobacco products at least once which included 40% male (116) and 9.1% females (43) students. The gender difference was statistically significant (p < 0.001). Among the male students who use tobacco products, 56.9% chewed tobacco with betel leaves while 24.1% were smokers. Another 16.1% were using both forms of tobacco and all the female users were tobacco chewers. Accordingly, when the total sample was considered, 16.8% chewed tobacco leaves while 6.2% were smokers. All smokers were males. The relationship between the gender and the type of tobacco products used, was statistically significant (p < 0.001). Elders in the family who use tobacco were the main influence for the children to start using them (56%). Friends also had strong impact on the boys (41%) but not much on the girls. Boys were almost equally interested in pleasure (48%) and experimenting (47%) while using tobacco products, whereas girls were mostly experimenting (84%). Stress relief and/ or peer pressure did not seem to be an important factor among the current study sample. All students were able to name at least one tobacco related health problems.

When the total sample was considered 52.9% did not have any family members using tobacco products. However, when only the tobacco users were considered, it was 81.1%. This relationship was statistically highly significant (p < 0.001). The type of tobacco products consumed by the family members appears to have an impact on the tobacco use by the children. When the tobacco using family members were considered, 87.2% chews it with the betel quid. Since betel chewing is considered as a habit associated with the Sri Lankan culture, it is not categorised as a bad or hazardous habit like smoking by many people. Instead, it may be even encouraged by some adults. It is also freely available in most of the households and there are no legal or social restrictions even for minors to acquire them. Therefore, these findings may be useful in implementing tobacco control policies in Sri Lanka.

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

68

Prevalence, Severity, Pattern of Dental Caries and Care Index of Six Year Old Primary School Children in a Semi Urban Area in Kandy, Sri Lanka

E.M.U.C.K. Herath1, B.G.T.L. Nandasena1, K. Perera2, A. Steepenson2, S.C. Ratnayake3, S. Sakuma4 and H. Miyazaki4

1

Faculty of Dental Sciences, University of Peradeniya

2

Faculty of Engineering, University of Peradeniya

3_{Medical Corps, Sri Lanka Army}

4_{Faculty of Dentistry, Graduate School of Medical and Dental Sciences, Niigata University,}

Japan

Dental caries is a significant health problem among Sri Lankan children and fluoride is the most important agent that can be used to control dental caries. The School based Fluoride Mouth Rinsing (SFMR) program is a world recognized economical dental caries preventive measure. The aim of the present study is to evaluate the prevalence, severity, and patterns of dental caries and care index of 6 year-old primary school children in a semi urban area in Kandy in order to implement a SFMR program.

This study group consisted of 410 children from six selected schools in Denuwara Educational Zonal, Kandy. The clinical oral examinations were carried out and the numbers of decayed, missing or filled teeth (DMFT/dmft index) or affected tooth surfaces (DMFS/dmfs index) were recorded. Care Index was adapted to assess the oral health care level of the population.

According to the study group, 32% children were caries-free, while the mean dmft was 3.5 (±0.36), mean dmfs was 6.78 (± 0.79) and mean DMFT was 0.02 (± 0.01) for the total sample. There was no statistically significant difference between males and females on the prevalence of caries. The decayed component of the dmft was 76.26% and the filled component was 10.74%. The Care Index which reflects the contribution made to the dmft by filled teeth (ft), of the present study was very low (10.61%) when compared to that of the British population (86.4%). Further, 11.8% of total sample showed Molar Incisor Hypomineralization (MIH). This suggests a high risk for demineralization of teeth in these children. In 1981, WHO and FDI (International Dental Federation) formulated an oral health goal for 5-6 year old children by year 2000, by which 50% of children would be caries free. However, our results indicate that we are far behind this goal even in 2010. Therefore, the necessity to develop preventive strategies such as SFMR program or water fluoridation or fluoride varnishing program is significant.

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

69

Denture Induced Stomatitis and Associated Factors in Patients Attending the Dental Hospital, Peradeniya, Sri Lanka

I.P Thilakumara1, P.R Jayasooriya2, J.A.M.S Jayatilake3, G.A.K.K. Abeypala1, R.L.P.R Liyanage2 and R.W Pallegama4

1

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

2

Department of Oral Pathology, Faculty of Dental Sciences, University of Peradeniya

3

Department of Oral Medicine and Periodontology, Faculty of Dental Sciences, University of Peradeniya

4

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

Denture induced stomatitis (DIS) is a common oral medical problem in the elderly denture wearers. Clinically, DIS is characterized by erythematic patches on the denture bearing mucosa in both jaws with a high predilection for maxilla. However, there is no consensus on the aetiological factors of DIS at present. Therefore, objectives of this study were to determine the factors associated with DIS, assess the feasibility of using the presence of hyphae in palatal smears and denture surfaces to diagnose Candida associated DIS and assess the oral and hand carriage of Candida by DIS patients.

Complete or Partial denture wearers (n=47) presented to the clinic with DIS from April to September 2011 were included in the study. An interviewer administered questionnaire was used to obtain socio-demographic data, medical and dental history, status of receiving post delivery instructions and denture and oral hygiene habits. Denture hygiene was assessed using modified Hoad-Reddic classification. Clinical type of DIS was recorded in Newton’s classification. A scraping from the palatal mucosa and a swab from the denture surface were obtained from each patient and stained with Periodic Acid Schiff stain to determine the presence of candidal hyphae. Concentrated oral rinse technique using 10 ml of sterile phosphate buffered saline was done in order to assess the oral yeast colonisation. Candidal hand carriage was assessed using fingerprints on a plate of Sabourad’s agar. Identification of Candida was done using colony characteristics and Gram’s stain.

There were 87.2% (n=41) Sinhalese, 6.4% (n=3) Tamils and 6.3% (n=3) Moors, out of which 89.4% (n=42) were female and 10.6% (n=5) were males. Their ages ranged from 31-80 years (mean = 56.91; SD = 10.07). Eighty three percent had received post delivery instructions. Unsatisfactory denture hygiene was observed in 70.2% of the upper dentures. Majority (66.0%) used dentures during sleep. Age of the current denture set varied from 1-41 years (Median = 10; Interquartile Range = 5-17). Most frequent clinical pattern of DIS was Newton type II (70.2%). Majority (57.7%) showed candidal hyphae on both palatal mucosa and denture. There were 55.3% (n=26) patients carrying Candida in oral cavity and in hands. The odds ratio for carrying Candida in hand by oral candidal carriers was 9.5.

Our observations are in agreement with a previous finding. The likelihood of carrying Candida in hand by an oral candidal carrier was very high. Factors such as denture hygiene, increased denture age and use during sleep may be associated with DIS. Denture hygiene was generally not satisfactory in majority in spite of high rate of receiving post delivery instructions.

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

70

Dental Practitioners’ Views on Adequacy of Undergraduate Training in Dental Laboratory Technology