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Year : 2012  |  Volume : 3  |  Issue : 3  |  Page : 106-111

A methodological pilot study on oral health of young, healthy males

1 Department of Cariology, Endodontology and Paedodontics, Institute of Dentistry, University of Oulu; Oulu University Hospital, Oulu, Finland
2 Department of Cariology, Endodontology and Paedodontics, Institute of Dentistry, University of Oulu, Oulu, Finland
3 Institute of Dentistry, University of Helsinki, Finland
4 Institute of Mathematical Sciences, University of Oulu, Finland
5 Centre For Military Medicine, Finnish Defence Forces, Finland

Date of Web Publication27-Nov-2012

Correspondence Address:
Vuokko Anttonen
Institute of Dentistry, University of Oulu
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Source of Support: The Finnish Dental Society in collaboration with Golgate Gaba awarded a grant to VA for this study, Conflict of Interest: None

DOI: 10.4103/2155-8213.103928

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Introduction: This study aimed to investigate the indications for an epidemiological survey on the oral health of young males, and the possibility of conducting it during their military service. Settings and Design: Despite the excellent oral health of young Finnish people in the past, there is concern about its degradation today. About 80% of young Finnish males enter the mandatory military service annually. The draftees have obligatory health inspection, with oral health screening, in the first two weeks of their service. Subjects and Methods: Self-reports on oral health were analyzed. Dental screening of conscripts performed by military dentists was timed and evaluated in two garrisons in 2010 (n = 256). Results: Over 40% of the conscripts reported having either dental symptoms or sensitivity after eating or drinking sour food or due to changes in temperature. Toothache was reported as having been the reason for the latest dental visit by 17% of the respondents. Clinical inspection took on an average almost three minutes and answering the questionnaire, almost 11 minutes. For evaluation of the process, the need for randomization of the study sample was emphasized as well as for specific guidelines, radiological education, and calibration of the dentists performing future survey to increase inter/intra examiner reliability. Moreover, the need for three computers per dentist for the questionnaires was pointed out. Discussion: The need for an epidemiological survey was indicated by a high number of respondents reporting dental symptoms and the need for treatment. An epidemiological survey is possible to be conducted by the existing military dental personnel, but they must be educated radiologically and calibrated. A specific protocol is essential.

Keywords: Oral health, survey, young adult

How to cite this article:
Anttonen V, Tanner T, Kämppi A, Päkkilä J, Tjäderhane L, Patinen P. A methodological pilot study on oral health of young, healthy males. Dent Hypotheses 2012;3:106-11

How to cite this URL:
Anttonen V, Tanner T, Kämppi A, Päkkilä J, Tjäderhane L, Patinen P. A methodological pilot study on oral health of young, healthy males. Dent Hypotheses [serial online] 2012 [cited 2023 Mar 22];3:106-11. Available from:

  Introduction Top

Despite the excellent oral health of the young Finnish in the past, degradation of their oral health has been suspected. [1],[2] The dietary habits of the young have undergone changes during the past decades internationally, snacking replacing regular meals. [3],[4] The frequency of toothbrushing in Finland, especially among boys and men, has remained among the lowest in Europe. [5],[6] Theses from earlier decades on conscripts showed regional differences in oral health as well as polarization of caries. [7],[8] About 80% of each age group enter the military service; the present-day conscripts were born in the early 1990s. The present study aimed to investigate self-reported oral health of the young, and to investigate if an epidemiological oral health survey could be conducted on conscripts by the present military dental personnel and using the military oral screening protocol [Table 1]. The process used in oral health screening in the Defence Force was evaluated and inspection timed. Data collection from different databases was also tested.
Table 1: Criteria of the Finland Defence Forces for recording findings of clinical inspection

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  Subjects and Methods Top

This pilot study was carried out in two garrisons of the Finnish Defence Forces in July 2010, during the health inspections of the conscripts in the first week of the military service (n = 256). Two dentists working in the Defence Forces carried out the oral inspection. They were advised to inspect as many conscripts as possible. They were not calibrated before the pilot study. Probe, oral mirror, and light of the dental unit were used for the inspections. The oral health screening aimed at determining the need for treatment of each conscript according to the protocol of the Defence Forces [Table 1]. The Mildoc® computer program of the Finnish Defence Forces was used to record the oral findings, which were registered by a dental assistant.

The Finnish evidence-based guidelines for controlling dental caries [9] were used as the criteria for taking bitewing (BW) radiographs. According to those criteria, BW radiography is indicated in the presence of even one active caries lesion having penetrated into the dentin. BW radiographs were advised to be taken when clinically indicated. The conventional number 2 oral films of Kodak Insight Dental Film® , (Eastman Kodak Co, Rochester, NY, USA) and Minray DC SL-9® X-ray devices, (CompareNetworks, Inc. San Francisco, CA, USA) were used. The exposure time was 0.28 seconds. The films were processed in an automatic Dürr Dental Periomat Plus® processor, (Dürr Dental AG, Bietigheim-Bissingen, Germany) using fresh Periomat Intra processing solutions. All films were developed and findings diagnosed and recorded after the clinical inspection.

In connection with the oral inspection, the conscripts answered a computer-based questionnaire developed by the Institute of Dentistry, University of Oulu, Finland, for investigating individual background factors and health behavior. This questionnaire has been used in a few studies on school children. [10],[11] The results of this can be combined and analyzed with clinical dental findings, [10] and answers can be analyzed individually or as summarized variables. A convenience sample of the respondents was used; the conscripts who were waiting for their turn for the oral inspection answered the questionnaire when the computer, placed in the waiting area, was available (n = 256). Two laptop computers with the questionnaires were provided for both garrisons.

The questionnaire comprised a total of 50 questions; the core of the questions were those used in earlier studies on dietary and oral hygiene issues [questions 17 to 37]. [10],[11] Four new questions on the use of energy and sports drinks, smoking, and consumption of alcohol and snuff were included in this section [questions 26 to 29]. In addition, the following questions were added to the questionnaire: Background information on social relationships, own education and education of parents, professions of parents and place of residence [1 to 12], free-time activities [13 to 14], general health and medications [15 to 16], sources of information of received dental health promotion (38), presence of dental symptoms/toothache [39 to 40], issues on dental attendance and received treatment, and estimated need for dental treatment (41 to 44; 47, 48), pain in the temporomandibular joints (TMJs) and facial area (45, 46), dental fear (49), and well-being (50) in association with oral health. It was pointed out in the questionnaire that the questions considered the period before entering the service, if not described differently. The alternative answers to the questions were of the following types: Yes/No, Never, Hardly ever/ Everyday, or Almost every day/Occasionally. The alternative was chosen by clicking on it on the computer screen. This information was automatically recoded and saved as a dBase file format for later analyses by statistical software (SPSS).

Answering the questionnaire was voluntary and by answering it the conscripts gave permission for use of their personal military records. All records on oral health and on some general health issues [body mass index (BMI) and diagnoses of systemic diseases], as well as on issues connected with the military service (i.e., unit and court of the service) were collected as separate databases from the Mildoc® for investigating data collection. These data were united with data from the questionnaire and prepared for analyses. All IDs (ID: identification) of the conscripts were excluded from the data before analyses. The key to the IDs was held by the University of Oulu and the Defence Forces as agreed in the project agreement between the parties.

Two PhD students (AK and TT) were in charge of evaluating and timing the procedures, and in training a medical assistant to help the conscripts in answering the questionnaire. Data collected included the duration of the clinical oral inspection with and without BW radiography and the duration of answering the questionnaire. Observations from the two study participants (AK and TT) regarding clinical procedures, radiography, and answering the questionnaire were collected as free comments [Appendix 1].

The results of the present study are descriptive and were executed with the SPSS (version 16.0, SPSS, Inc., Chicago, Il, USA) and R software (version 2.11.1 patched; a language and environment for statistical computing; R Foundation for Statistical Computing, Vienna, Austria, URL ).

  Ethical Aspects Top

The conscripts gave their consent for the use of their patient records by answering the voluntary computer-assisted questionnaire-only patient records of those having given their consent were used in this study (n = 256). For the analyses, the IDs were excluded. The research plan for the later oral health survey of conscripts in the Finnish Defence Forces was evaluated by the Ethical Committee of the Northern Ostrobothnia Hospital District and positive consent was given on March 29, 2010. The Centre of Military Medicine and the Defence Staff gave permission for the study in June 2010 (AG14218/23.6.2010).

  Results Top

Eighty-three percent of the conscripts reported having visited the dentist within two years, and about 17% had visited the dentist because of toothache. Almost 40% estimated having a need for dental treatment at the time of the survey. Toothache or some other dental symptom was reported by 14.6%, and sensitivity of the teeth due to temperature changes or after eating or drinking anything sour by 26.5%. One-fourth (25.7%) of the participants did not consider regular checkups important.

Clinical inspections of 131 conscripts were timed. The mean time spent for clinical oral inspection per conscript was 2 minutes 48 seconds (range: 1 min 55 s to 3 min 11 s). The use of radiographs added 1 minute 01 seconds to that [Table 2]. It took 1 hour 36 minutes 00 seconds to develop, diagnose, and record radiographic findings of 17 men (45% of the conscripts in the garrison number 1). Answering the questionnaire took on an average 10 minutes 47 seconds (6 min 26 s to 15 min 27 s) [Table 2]. The response rate was 100%.
Table 2: Timing for different procedures of clinical inspection and answering the questionnaire

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In the free comments by AK and TT, the need for three computers per dentist was raised to enable as many conscripts as possible participating in the oral inspection to answer the questionnaire. Most of the questions in the questionnaire caused no comments from the respondents. However, they questioned if migraine or pollen allergy were considered chronic illnesses (Yes and No, respectively), and if Net poker was considered a computer game (Yes). They also queried whom a conscript should report having shared accommodation with, if he shared his time between his divorced parents (The one in whose home he got his mail). They wondered if a conscript had both studied and worked during the past six months before the service he should report it as the main job. They also questioned if one dose of alcohol/week was considered as use of alcohol (Yes).

Also, the need for radiological education and calibration of the dentists performing oral inspections was emphasized. Similarly, guidelines for determining the need for restorations due to dental caries, the need for periodontal treatment, as well as the need for endodontic treatment and radiography were considered essential. The need for guidelines for recording additional oral findings in a structured manner, that is, the number of gingival bleeding sextants, the presence of traumatized and deciduous teeth, oral mucosal piercing, and active orthodontic appliances was emphasized. Trained auxiliary staff was considered necessary in each inspecting team; at least one person for assisting in clinical inspections, one in helping with the questionnaire and, if possible, one for developing X-rays. Final data were collected from separate databases (Mildoc® oral health, Mildoc® general health, Mildoc® general information, and the questionnaire). Collecting and preparing data from several sources caused no difficulties.

  Discussion Top

According to the present pilot study, self-estimated oral symptoms and the need for treatment were reasonably high, considering that these youngsters had been entitled dental care free of charge all their lives. About 40% estimated a need for treatment, 14.6% reported toothache or other symptoms, and 26.5% reported sensitivity to changes in temperature or when eating or drinking anything sour. The figures must be taken even more seriously considering that those entering the military service are physically and mentally healthy. A national oral health survey would be possible to be conducted with the present resources in the oral health section of the Defence Forces and within the limited time for inspections by randomizing the study sample in the biggest garrisons. A precise protocol, guidelines, radiological education, and calibration were emphasized in the evaluation feedback of the pilot study. The protocol for an epidemiological study of young adults was specifically defined after the present pilot study [Figure 1].
Figure 1: The study protocol for conducting an epidemiological study on Finnish conscripts

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The latest national study on the oral health of Finnish young adults in the beginning of the 2000s [6] revealed the greatest and most consistent differences between groups with different levels of education, as was also observed by Ankkuriniemi [7] and Läärä. [8] In the Finland Health 2000 Survey, dental symptoms were reported by 36% of the respondents (in the age group 30 to 44), and 54% of that age group estimated having a need for dental treatment. [6] The respective figures in the present study are 26.5% and almost 40%. The results indicate a surprisingly high level of self-reported need for treatment and poor oral health already among young adults. The same was true of the high number of those whose latest visit to a dentist was indicated by dental symptoms (17%). These facts indicate the need for a national epidemiological study on young adults. This study is also interesting internationally, when research is needed to investigate the occurrence of caries in the industrialized world in an era after a strong decline of the prevalence of caries. [12]

The pilot enabled to determine that all conscripts can be inspected in all but five garrisons. Because the conscripts enter inspection unit by unit in alphabetical order, randomization is done by picking every fifth person, and in his absence, the following one. This means that oral health and health behavior of more than 14,000 draftees can be analyzed. In the theses of both Ankkuriniemi [7] and Läärä, [8] similar random samplings were used. The number of participants was 3,936 and 2,850, respectively. Thus, the number of participants in the future study would considerably exceed those of the earlier studies ensuring its reliability in all parts of the country. Any other type of randomization would not be possible, because of the context of the inspection as a part of health inspection with a strict time limit. Female and male conscripts serve in same units; so, randomization includes both genders. The study protocol allows data on the female conscripts to be investigated separately avoiding generalizations due to the small sample size.

The need for radiological education and calibration of dentists running the field study was emphasized in the evaluation. Education and calibration must be carried out before the field survey, as was also the case in Ankkuriniemi's study, [7] but not in Läärä's, [8] even though data collected from the files of the patients have been found to be reliable. [13] In the present study, calibration was not done and therefore no clinical findings are presented here. The time limit in the dental inspection per draftee allows estimation of the need for cariological treatment toothwise [DMFT (DMFT: decayed, missing, filled teeth), DT (DT: decayed teeth)]. Both cariological findings and periodontal health will be recorded as defined in the World Health organization (WHO) criteria for epidemiological studies. [14] From analyses, data on wisdom teeth will be excluded because the need for treatment in them is generally registered as caries, even in cases where the cause can be for example pericoronitis-which would cause bias in the results. Recording bleeding in the index teeth would allow analyzing a proportion of infected areas. Some additional findings, such as the presence of traumatized and deciduous teeth as well as of active orthodontic treatment and piercings, if reported in a structured manner, would give valuable information.

No education was given on taking BW radiographs, only recommendation to take them when clinically indicated, which allowed estimation of the need for radiography as well as the time needed for it. According to the pilot, this would mean radiography of about 40% of the inspected draftees, which is not possible to achieve within the time limit. Therefore in the future study, radiographs should be taken only for every fifth draftee with a clinical indication for radiography. Conventional or digitized radiography techniques can be used. The dentists should be educated radiographically for technique and diagnostics before the field survey of the future study. For verification, the radiographs should also be analyzed by a specialist.

The response rate to the questionnaire was exceptionally high. So, high participation will allow analyses of health and oral health behavior as well as association between oral health and background factors to be generalized and used for planning for health resources. This will also give information on how to approach this age group and the clusters within it educationally. Health indexes per se such as DMFT, DT, and CPITN (CPITN: community periodontal index for treatment needs), which can be produced automatically from the files of the patients by the Mildoc® program without identification, can be analyzed without written consent from the individuals. The pilot study revealed that answering the questionnaire took three times longer than clinical inspection. Therefore the need for three computers per dentist will be taken into action to enable as many draftees as possible to answer the questionnaire. In the present study, the questionnaire was only in Finnish. Because Finland has two official languages, Finnish and Swedish, the questionnaire must be translated into Swedish for the later study.

According to the pilot study, the study protocol and obtaining the data had no major deficiencies. Standardized protocol, guidelines, calibration, and radiological education of dentists were, however, emphasized. Following the simple protocol of the Defence Forces and the WHO guidelines, a cross-sectional national epidemiological study on oral health, general health, and health behavior of young males can be accomplished during their mandatory military service.

  Acknowledgments Top

The authors wish to thank Dr. Ahti Niinimaa for recoding the questionnaire for this pilot study. They are especially grateful to Dr. Risto Pesola and Dr. Jussi Arjavaara for participating in the pilot study and providing their input for designing the Oral health of the conscripts 2011-study in the Finnish Defence Forces further. They also wish to thank the staff and the medical conscripts in the garrisons. There are no personal or financial conflicts of interest for any of the members of the research team in this study. The Finnish Dental Society in collaboration with Golgate Gaba awarded a grant to VA for this study.

  References Top

1.Anttonen V, Yli-Urpo H. Oral health of Finnish children at the beginning of the 2010s - Results from a survey sent to dentists working in public health care oral health of Finnish children at the beginning of the 2010s. Finn Dent J 2010;17:20-5.  Back to cited text no. 1
2.Nordblad A, Suominen-Taipale L, Rasilainen J, Karhunen T. Oral Health Care at Health Centres from the 1970′s to the year 2000. In Finnish with English Summary. Saarijärvi, Finland: Gummerus Kirjapaino; STAKES Reports (National Institute for Health and Welfare, NIHW) 278/2004:44.  Back to cited text no. 2
3.Currie C, Gabhainn S, Godeau E, Roberts C, Smith R, Currie D, et al. Inequalities in young people′s health: Health behavior in school-aged children (HBSC) International report from the 2005/2006 survey [Internet]. Copenhagen, Denmark: WHO regional office for Europe. 2008 June Available from: 1. [Last accessed on 2011 Dec].  Back to cited text no. 3
4.Popkin BM, Adair LS, Ng SW. Global nutrition transition and the pandemic of obesity in developing countries. Nutr Rev 2012;70:3-21.  Back to cited text no. 4
5.School Health Survey in secondary Schools 2008. National Institute for Health and Welfare. 2009 Available from: [Last accessed on 2011 Dec].  Back to cited text no. 5
6.Suominen-Taipale L, Nordblad A, Vehkalahti M, Aromaa A, eds. Oral health in the Finnish adult population. KTL-National Public Health Institute, Finland, Department of Health and Functional Capacity, Helsinki, Finland. 2008. Available from: [Last accessed on 2011 Dec].  Back to cited text no. 6
7.Ankkuriniemi O. The dental status and need for dental treatment among Finnish conscripts. Doctoral Thesis. Kouvola, Finland: Lehtikanta Oy; 1979.  Back to cited text no. 7
8.Läärä M. Polarization of dental caries and the explanatory background factors in a Finnish conscript population. Doctoral Thesis. Turku, Finland: Painosalama Oy; 1999.  Back to cited text no. 8
9.Evidence based guidelines for controlling dental caries. [Published 2.2009]. Available from: [Last accessed on 2012 May 30]  Back to cited text no. 9
10.Anttonen V, Hausen H, Seppä L, Niinimaa A. Effect of dietary habits on laser fluorescence values of visually sound occlusal surfaces among Finnish schoolchildren. Int J Paediatr Dent 2008;18:124-30.  Back to cited text no. 10
11.Anttonen V, Seppä L, Niinimaa A, Hausen H. Dietary and oral hygiene intervention in secondary school pupils. Int J Paediatr Dent 2011;21:81-8.  Back to cited text no. 11
12.Marthaler TM. Changes in dental caries 1953-2003. Caries Res 2004;38:173-81.  Back to cited text no. 12
13.Seppä L, Hausen H, Kärkkäinen S, Larmas M. Caries occurrence in a fluoridated and a nonfluoridated town in Finland: A retrospective study using longitudinal data from public dental records. Caries Res 2002;36:308-14.  Back to cited text no. 13
14.WHO. Extracts of the Fourth edition of Oral Health Surveys- Basic methods, 1997. Available from: [Last accessed on 2010 Nov 10].  Back to cited text no. 14


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