Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2016  |  Volume : 4  |  Issue : 1  |  Page : 13-18

Prevalence of dental caries and pattern of sugar consumption among junior secondary school students in Northcentral Nigeria


1 Department of Oral Surgery, Dental Clinic, University of Ilorin, Ilorin, Nigeria
2 Department of Dental and Maxillofacial Surgery, University of Ilorin Teaching Hospital, Ilorin, Nigeria
3 Department of Oral Biology and Oral Pathology, Faculty of Dental Science, College of Medicine, University of Lagos, Lagos, Nigeria
4 Department of Restorative Dentistry, Faculty of Dentistry, College of Medicine, University of Ibadan/University College Hospital, Ibadan, Nigeria
5 Department of Dental and Maxillofacial Surgery, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria
6 Department of Surgery, College of Health Sciences, Usmanu Danfodiyo University Sokoto, Sokoto, Nigeria

Date of Web Publication2-Jul-2018

Correspondence Address:
Dr. Ramat Oyebunmi Braimah
Department of Dental and Maxillofacial Surgery, Usmanu Danfodio University Teaching Hospital, Sokoto, Sokoto State
Nigeria
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/njecp.njecp_19_16

Rights and Permissions
  Abstract 


Aim: The aim of the study was to determine the prevalence of dental caries among 12-year-old JSS pupils in the local government and the correlation with refined carbohydrate consumption pattern. Patients and Methods: A dental survey (The World Health Organization [WHO] “pathfinder” survey) was conducted utilizing five private junior secondary schools (JSS) and ten public JSS with pupils of JSS 1–3. These schools were chosen by a simple random sampling from the five geographical areas of the local government. All participants had dental examination for oral hygiene and dental caries experience using the decayed (D), missing (M), filled (F), and treated (T) teeth (DMFT) codes, respectively. Results: A total number of 394 JSS pupils were examined in Ilorin West Local Government Area of Kwara State. A low caries prevalent level of 34% (DMFT ≥1) was observed. The mean DMFT for the study population was 0.69 (+1.2). This is better than the WHO. maximum of 3DMFT by the age of 12 years. The mean DMFT for male pupils was 0.66 (+1.2) and for female 0.72 (+1.2) (P = 0.592). This observed difference was not statistically significant. However, the mean DMFT for public schools was 0.80 (+1.3) and for private schools, it was 0.36 (+0.83) (P = 0.00104). This observed difference was statistically significant. There appears to be no statistically significant association between DMFT and frequency of consumption of confectionaries generally. Conclusion: There is a higher caries level among students in public secondary schools compared to those in private secondary schools in the local government.

Keywords: Dental caries, oral health, prevalence, schools, students, sugar


How to cite this article:
Kalejaiye HA, Adeyemi MF, Akinshipo A, Sulaiman AO, Braimah RO, Ibikunle AA, Taiwo AO. Prevalence of dental caries and pattern of sugar consumption among junior secondary school students in Northcentral Nigeria. Niger J Exp Clin Biosci 2016;4:13-8

How to cite this URL:
Kalejaiye HA, Adeyemi MF, Akinshipo A, Sulaiman AO, Braimah RO, Ibikunle AA, Taiwo AO. Prevalence of dental caries and pattern of sugar consumption among junior secondary school students in Northcentral Nigeria. Niger J Exp Clin Biosci [serial online] 2016 [cited 2018 Jul 19];4:13-8. Available from: http://www.njecbonline.org/text.asp?2016/4/1/13/235804




  Introduction Top


Oral diseases, especially dental caries and periodontal disease are serious public health problem worldwide.[1],[2],[3] Several studies from Nigeria and other developing countries have implicated dental caries as the major determinants of pain, swelling, infections, loss of sleep, disturbance of mastication, reduction in quality of life, tooth loss, and sometimes death.[2],[3],[4],[5] This also has been identified in school children as a major cause of public health challenge.[2] The adoption of preventive strategies, especially in schools would help to reduce these negative impacts and help to inculcate good oral hygiene among this vulnerable section of the population.[2],[6]

Researches indicate that proper implementation of recommended primary prevention, especially in children of schoolgoing age is predicated on reliable database.[1],[2],[6] However, there is a paucity of data on the prevalence of dental caries among junior secondary school (JSS) children in our region to facilitate planning of proper interventions for prevention of dental caries. To the best of our knowledge, this is the first of such study from our center and the Northcentral region.

Hence, the purpose of this study is to determine the prevalence of dental caries and consumption of refined carbohydrate among 12-year-old JSS in our local government area (LGA).


  Patients and Methods Top


This was a population-based cross-sectional study carried out between January 2004 and December 2004. A standardized questionnaire was used to assess the pattern of sugar consumption and oral hygiene practices of the participants. It was designed by the principal investigator with inputs from other coinvestigators so as to aid minimal interviewing.

Study location

The study was conducted in Ilorin West LGA of Kwara State. According to the National Population Commission (NPC), Kwara State has an estimated 1991 population figure of 1.6 million people. Using an annual growth rate of Nigeria, which is currently 2.9%, the 2004 population is projected at 2.32 m people. There are 16 LGAs in Kwara state altogether. The LGA created in 1991 out of the former Ilorin Local Government. The LGA has a 1991 population figure of 184,541 inhabitants (NPC, 1991). With an annual growth rate of 2.9%, the 2004 population is projected to be 267,604 inhabitants. The LGA. covers an area of 54.2 km 2 (Public relation officer (PRO) of the local government). There are four districts in the local government and each has its historical antecedents. There are Alanamu, Ajikobi, MagajiNgeri, and Wara/Osin/Egbejila (information unit of Ilorin West LGA). There are 12 political wards in the local government. The predominant ethnic groups are the Yoruba. Islam and Christianity are the two major religions practiced by the people. The main languages of communication are Yoruba and English. The people are mostly civil servants while others are engaged in craftwork, farming, trading, and other private business. There are several health facilities in the local government. The local government owns some and some are owned by the state while some are privately owned. The University of Ilorin Teaching Hospital is situated in this local government. The Government Dental Center owned by the state is located within the same premises as the Teaching Hospital. There are four private dental clinics within the LGA.

Sampling frame

The total number of public schools in Ilorin West LGA is 17. The schools in Ilorin West Local Government were stratified into two public and private. There are 14 registered private secondary schools in the local government according to the Statistics unit Kwara State Ministry of Education.

The LGA has a total student population of 23,896 as at the end of year 2003 with 12,621 in JSS arm. This represents 18.8% of the total students' population in Ilorin. About 30.3% of JSS student are 12-year-old (Statistics Unit, Kwara State Ministry of Education). This translates to a simple population of 3824.

Sampling method

A multistage cluster sampling technique was used for the survey. Six public schools were selected through simple random sampling by balloting technique, while two private schools were also selected through the same technique. Each arm of JSS 1–3 was used as a cluster. An arm in each class was selected by simple random sampling. In other words, an arm was chosen from JSS 1, another arm from JSS II another arm from JSS III. These arms are generally where we expect the 12-year-old students to aggregate. The number of students in each chosen cluster of JSS class was sampled. The selected students were asked to seat in a vacant class or school hall where available. The sample interval was 5 and the first student to be included in the sample was chosen randomly by asking any of the students to pick one out of five pieces of paper numbered 1–5. If the number 3 is picked, then every 5th student was included in the sample starting with student number 3 on until ten students were selected. The numbers selected would then be 3, 8, 13, 18, 23, 28, 33, 43, and 48.

Sample selection

Before the visit, community leaders, parents, teachers, and the school authorities were informed of the proposed study, their consent sought and they were encouraged to mobilize participants from their locality for the study. With the assistance of the principal and teachers of the selected schools, the list of 12-year-old students was obtained (sample population). Participants were sequentially recruited based on the following criteria: must be 12-year-old as at last birthday, should reside in the LGA, must be in secondary located in the locality, and must be willing to participate in the study. Participants below or above 12-year-old, not in secondary school in the locality or who were unwilling to participate in the study were excluded.

Data collection

The decayed (D), missing (M), filled (F), and treated (T) teeth (DMFT) index was used to assess the caries activity. The DMFT is a means to numerically express the caries prevalence and are obtained by calculating the number of DMFT. It was calculated for 28 teeth since the last molars would not erupt until about the age of 18 years. The sum of the three figures formed the DMFT score. A DMFT score of 3+2+7 = 12 means that three teeth are decayed; two teeth are missing while seven teeth have been filled. For a 12-year-old with a maximum number of 28 teeth, it also means that 16 teeth are intact.

The instruments used were plane mouth mirror and sharp dental probe (for exploration of tooth surface). The other instrument used was a structured questionnaire. The questionnaire was pretested to ensure simplicity and ease of understanding by the participants. Appropriate changes were made to the questionnaire before data collection. A chemist also tested some “pure water” samples for the presence or absence of fluoride. This was done to find out if some pupils had access to fluoride other than from toothpaste and which in turn might affect their caries status.

Demographic data were obtained from the students after which the students were examined. Selected students were examined seated on an ordinary seat back chair and natural light source and following the World Health Organization (WHO) criteria for assessing dental caries.[7] Neither the use of radiography nor the use of fiber optics for caries detection was practicable in this study due to logistics, risk, cost, and time. Examination was carried out in an orderly manner from one tooth or tooth space to another tooth. Some teachers in the selected schools were trained and were requested to help administer the questionnaire. The DMFT index observed by the researcher was also recorded. A day was set aside for each selected school to prevent minimal disruption of their activities.

Data instrument

A structural interview was conducted for each of the respondents. The assistance of the class teacher for each arm of JSS class was sought in this regard. The reason is that some questions were open-ended while some were close-ended. There were questions on sex, oral hygiene habits and behavior, dietary habits, and past dental history if any. This was followed by the examination of their dentition for dental caries.

Diagnostic criteria

A tooth was considered present in the mouth if any part of it was visible. If a permanent and a milk tooth occupied the same space, the status of the permanent tooth only was recorded. A tooth was considered carious if it had an unmistakable cavity. The dental probe was used to confirm visual presence of caries on the occlusal, buccal, and lingual surface. Where there was any iota of doubt, caries was not recorded, if a tooth had both a carious lesion and a filling. It was charted carious. This is the standard prescribed by the WHO.[7]

Ethical considerations

Permissions to conduct the study were obtained from the LGA educational authority and letters of introduction were obtained from the Department of Epidemiology and Community Health to the selected schools. The researchers explained to all the study participants the scope, aims, and objectives of the study as well as their voluntary rights to participate or withdraw from the study with no penalty. All study participants gave verbal consent and were assured that their confidentiality would be maintained.

Data analysis

Data analysis was done after a careful compilation of data. Data entry and analysis was done using EPI info computer program. Univariate analysis was carried out; means and standard deviation were computed for quantitative variables and frequency distributions generated for qualitative variables. Bivariate analysis to identify associations between dependent variables of DMFT and sugar consumption with independent variables of gender and schools type (i.e., public or private) of the study participants was also carried out. The Student t-test was used to compare differences in DMFT. The Chi-square test was used for comparing proportions. Level of significance was considered at P ≤ 0.05.


  Results Top


A total number of 394 12-year-old pupils were seen in the study. A total of 199 (50.50%) were males, while 195 (49.50%) were females. Of the 394 pupils seen, 296 (75.13%) were drawn from public schools, while 98 (24.87%) were drawn from private schools.

Two hundred and sixty (66.00%) were caries-free (DMFT = 0) while 134 had caries indicating a prevalence of 34% (DMFT > 0).

The mean DMFT for the study population was 0.69 ± 12. The mean DMFT for males was 0.66 ± 12 and for females 0.72 ± 12. This observed different is not statistically significant (P = 0.592). The mean DMFT for public schools was 0.80 ± 1.3 while that for private schools was 0.36 ± 0.83 [Table 1] and [Table 2]. This observed difference is statistically significant (P = 0.0014). The public schools have DMFT of 38.5% compared to private schools where only 20 (20.41%) have DMFT.
Table 1: Cross tabulation of decayed, missing, filled, teeth and frequency of consumption of confectioneries among public school pupils

Click here to view
Table 2: Cross tabulation of decayed, missing, filled teeth and frequency of consumption of confectioneries private school pupils

Click here to view


Dietary habits of the respondents revealed that 89.5% of the pupils eat thrice daily. Majority (71.1%) also eats in-between meals. About 15% of the respondents claim that they eat biscuits and sweet everyday, 28% twice weekly and 57% eat biscuits and sweet once in a while. In this study, there appears to be no statistically significant association between DMFT and frequency of consumption of confectionaries generally (P = 0.8).


  Discussion Top


The finding in this study compares favorably to similar recent studies by Okeigbemen [8] from South-South Nigeria where 33% caries prevalence was reported among 12–15-year-old school children and Pitts et al.[9] among 12-year-olds in England and Wales is 38%. In contrast, the prevalence of dental caries seen in this study is twice that seen in the study of Umesi and Savage [10] in 2002 who reported a caries prevalence of 17% among 12-year-old Nigerians in Lagos, Southwest Nigeria. According to the WHO,[11] a prevalence of 20% dental caries in a population is acceptable.

The 67% caries-free level seen in this study is <98% caries-free level observed in some Nigerian participants by Sheiham [12] and 83% in 12-year-old children obtained by Umesi and Savage [10] in Lagos. The minor variation in prevalence of dental caries in different parts of the world may not be as wide as previously thought among different geographical boundaries.[13] The lower prevalence in both earlier studies [10],[14] could be due to their lower sample size compare to this present study.

The activity of dental caries seen in this study is very low. The mean DMFT for the study population was 0.69 ± 1.2. This is comparable to a mean DMFT of 0.73 reported by Okeigbemen.[8] The mean DMFT of 0.69 seen in this study is also within the range of the mean DMFT seen across England and Wales by Pitts et al.[9] The mean DMFT obtained in this study is however higher than that obtained by Umesi and Savage.[10] Some other studies reported a mean DMFT of 2.8 and 5.6.[15],[16] The WHO [17] desires a maximum of DMFT of 3 at age 12 years by the year 2000. The mean DMFT of 0.69 ± 1.2 obtained in this study is therefore an indication of low caries prevalence.

While noting that neither the public water supplies to Ilorin metropolis nor the samples of “pure water” tested has fluoride, the use of fluoride-containing toothpaste by the respondents could be responsible for the low caries prevalence and severity seen in this study. As far back as 1938, Dean [18] has documented the role of fluoride in the prevention of dental caries. The same fact has also been confirmed by some other studies.[1],[2],[19],[20],[21]

In some studies,[22],[23],[24] it was observed that females tend to have higher caries prevalence compared to their male counterparts. In this study, there is no observed difference between the two genders in caries level. Another study [14] however revealed a higher prevalence in males (0.25) compared to females (mean DMFT 0.92). One significant observation seen in this study is that the mean DMFT in public schools is greater than that of private schools. This observed difference is highly statistically significant. This is in contrast to another study [14] where a higher prevalence of dental caries was seen among 12–15-year-old private schools pupils (1.23) compared to public schools (0.83).

It used to be observed that since consumption of confectioneries is associated with dental caries, parents of high socioeconomic classes who can afford to send their children to private schools would also indulge them by buying confectioneries for them or give them the money to do so. This was thought to be responsible for higher caries prevalence among private school pupils seen in some studies.[9],[12],[17],[23],[25],[26] The high prevalence of dental caries among public schools in this study could be due to a variety of factors. First, the economic situation in the country is getting worse. This means there might be less money to spare for confectioneries by public school pupils in the sample population compared with that of private schools. As reported by Carlos,[27] mechanical removal of dental plaque by those that can invest the necessary time and effort results in lower caries prevalence. In addition, better monitoring and strict adherence to movement in and outside the school premises during school hours among private schools as observed during the study may be responsible. This might reduce the tendency of between meals eating. However, Ripa et al.[28] asserted that there is no significant relationship between the oral hygiene of teenage children and their caries scores.

About 71.1% respondents eat in-between meals. This is hardly surprising since most schools organize private lessons and preparatory classes for their pupils. Parents who could not package lunch for their wards would have to make do with snacks. In this study, however, there is no statistically significant association between frequency of consumption of confectioneries and DMFT among public and private school pupils which is in disagreement with several works.[9],[12],[17],[26],[29],[30] Dental caries is a multifactorial disease,[1] other factors such as oral hygiene habits and use of fluoride toothpaste may be responsible for lack of association between consumption of confectioneries and severity of dental caries.

Only 19.7% of the respondents in this study claimed that they have visited the dentist before. In a study by Umesi and Savage,[10] only 10% of this study population has also been to the dentist before. These could also be due to apathy or ignorance on the importance of routine visits to the dentist. This could also be a reflection of low availability of functional dental services in locality.

The care index (FT/DMFT ×100) is an indication of the restorative care of those who are suffering from dental caries. It therefore has to be viewed in conjunction with DMFT. These results are of interest in the provision of dental services to these age groups. In this study, the care index is just 1.5%. This figure is too low compared to that of 12-year-old pupils in England who recorded a care index of 48% 18- and 14-year-olds in Wales who recorded a care index of 58%.

The limitations of this study include reliance on self-reported information from the participant which might be subject to information and recall bias. Moreover, the lack of radiological facilities to detect incipient and proximal caries which might have lead to underdetection of the caries activity, thus, contributing to the low prevalence level of caries reported in the study.


  Conclusion Top


The current study demonstrated a low prevalence of dental caries and sugar consumption among this cohort. However, the study suggests that there is no association between frequency of consumption of confectioneries and DMFT among public and private school pupils but showed a higher caries level among those in public schools compared to those in private school. Hence, we recommend oral health promotion for these students in public secondary school.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Petersen PE, Bourgeois D, Ogawa H, Estupinan-Day S, Ndiaye C. The global burden of oral diseases and risks to oral health. Bull World Health Organ 2005;83:661-9.  Back to cited text no. 1
[PUBMED]    
2.
Taiwo OA, Sulaiman AO, Obileye MF, Akinshipo A, Uwumwonse AO, Soremi OO. Patterns and reasons for childhood tooth extraction in Northwest Nigeria. J Pediatr Dent 2014;2:83-7.  Back to cited text no. 2
  [Full text]  
3.
Taiwo OA, Alabi OA, Yusuf OM, Ololo O, Olawole WO, Adeyemo WI, et al. Reasons and pattern of tooth extraction among patients presenting at a Nigerian semi-rural specialist hospital. Nig Q J Hosp Med 2012;22:200-4.  Back to cited text no. 3
    
4.
Oginni FO. Tooth loss in a sub-urban Nigerian population: Causes and pattern of mortality revisited. Int Dent J 2005;55:17-23.  Back to cited text no. 4
[PUBMED]    
5.
Lesolang RR, Motloba DP, Lalloo R. Patterns and reasons for tooth extraction at the Winterveldt clinic: 1998-2002. SADJ 2009;64:214-5, 218.  Back to cited text no. 5
[PUBMED]    
6.
Folayan MO, Chukwumah NM, Onyejaka N, Adeniyi AA, Olatosi OO. Appraisal of the national response to the caries epidemic in children in Nigeria. BMC Oral Health 2014;14:76.  Back to cited text no. 6
[PUBMED]    
7.
Clark CA, Fintz JB, Taylor R. Effects of the control of plaque on the progression of dental caries: Results after 19 months. J Dent Res 1974;53:1468-74.  Back to cited text no. 7
[PUBMED]    
8.
Okeigbemen SA. Dental Caries Experience Among 12-15 Year Old School Children in Egor, Nigeria: Report of a Local Survey and Campaign. SvenskaMassan: General Session of the International Association for dental Research; 2003. p. 25-8.  Back to cited text no. 8
    
9.
Pitts NB, Boyles J, Nugent ZJ, Thomas N, Pine CM. The dental caries experience of 11-year-old children in Great Britain. Surveys coordinated by the British association for the study of community dentistry in 2004/2005. Community Dent Health 2006;23:44-57.  Back to cited text no. 9
[PUBMED]    
10.
Umesi DC, Savage KO. Dental caries status and treatment needs in 12-year-old Nigerians. Niger J Community Med Prim Health Care 2002;14:6.  Back to cited text no. 10
    
11.
World Health Organization. Oral Health Surveys Basic Methods. WHO/Area Country Profile Programme, WHO Headquarters, Oral Health Programm (NPH), WHO Collaborating Center, Malmo University. 4th ed. Sweden; World Health Organization; 1997. p. 39-44.  Back to cited text no. 11
    
12.
Sheiham A. The prevalence of dental caries in a Nigerian population. BDJ 1967;23:144-8.  Back to cited text no. 12
    
13.
Bitten RH, Perrot GS. Summary of physical findings on men drafted in world war. Public Health Rep 1941;56:4162.  Back to cited text no. 13
    
14.
Noah OM. The prevalence and distribution of dental caries and state of oral cleanliness in 5-years-old Ibadan Primary School Children. Niger Dent J 1984;5:44-51.  Back to cited text no. 14
    
15.
Jeboda SO. Dental caries. Niger Med Pract 1983;5:5-9.  Back to cited text no. 15
    
16.
Burt BA, Eklund SA. Dentistry, Dental Practice and the Community. 5th ed. Philadelphia, Pennsylvania: W.B. Saunders; 1999. p. 317-9.  Back to cited text no. 16
    
17.
WHO. Oral health country/Area programme, Oral disease prevalence in Zambia. Chitu Tembo Dent J 1987;2:10-2.  Back to cited text no. 17
    
18.
Dean HT. Endemic fluorosis and its relation to dental caries. Public Health Rep (New York) 1938;53:1443-52.  Back to cited text no. 18
    
19.
Dean HT. On the epidemiology of fluorine and dental caries. In: Gies WJ, editors. Fluorine in Dental Public Health. New York: New York Institute of Clinical Oral Pathology; 1945. p. 19-30.  Back to cited text no. 19
    
20.
Public Health Service. Public Health Service Drinking Water Standards – Revised 1962. Publication No 956. Washington DC: US Department of Health, Education and Welfare, PHS; 1962. p. 233.  Back to cited text no. 20
    
21.
National Research Council. Health Effect of Ingested Fluoride. Washington DC: National Academy Press; 1993.  Back to cited text no. 21
    
22.
Featherstone JD. Prevention and reversal of dental caries: Role of low level fluoride. Community Dent Oral Epidemiol 1999;27:31-40.  Back to cited text no. 22
[PUBMED]    
23.
Centers for Disease Control and Prevention. Achievements in public water fluoridation, 1900-1999: Fluoridation of drinking water to prevent dental caries. MMWR Morb Mortal Wkly Rep 1999;48:993-40.  Back to cited text no. 23
    
24.
Mann J, Cohen HS, Fisher R, Tamari I, Berg RG, Fischman SL, et al. Prevalence of dental caries among Ethiopian emmigrants. Int Dent J 1994;44:480-4.  Back to cited text no. 24
    
25.
Adegbembo AO. Relationship between Urbanism, diet and Population and Development. Syntheses de Research Aches; 1996. Available from: http://www.uaps.org/journal/synthesis.html.[Last accessed 2016 Aug 16].  Back to cited text no. 25
    
26.
Amaratunge A, Paulson S, Lind PO. Dental caries in a group of school children in Kandy, Srilanka. Acta Dent Scar 1980;38:263-8.  Back to cited text no. 26
    
27.
Carlos JP. Plaque prevention and removal by personal oral hygiene. In: Prevention and Oral Health. DHEW Pub No (NH) 74-707. Washington, DC: GPO; 1974. p. 31-4.  Back to cited text no. 27
    
28.
Ripa LW, Barenie JT, Leske GS. The relationship between oral hygiene and dental health. An epidemiological survey. N Y State Dent J 1977;43:530-5.  Back to cited text no. 28
[PUBMED]    
29.
Burt BA. Influences for change in the dental health status of populations: An historical perspective. J Public Health Dent 1978;38:272-88.  Back to cited text no. 29
[PUBMED]    
30.
Adegbembo AO, el-Nadeef MA, Adeyinka A. National survey of dental caries status and treatment needs in Nigeria. Int Dent J 1995;45:35-44.  Back to cited text no. 30
[PUBMED]    



 
 
    Tables

  [Table 1], [Table 2]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
   Abstract
  Introduction
  Patients and Methods
  Results
  Discussion
  Conclusion
   References
   Article Tables

 Article Access Statistics
    Viewed34    
    Printed2    
    Emailed0    
    PDF Downloaded16    
    Comments [Add]    

Recommend this journal