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Oral health status in a population in Northern Norway Per W. Norheim
a
a
Department of Prosthetic Dentistry, Dental Faculty, University of Oslo, Oslo, Norway Published online: 23 May 2015.
To cite this article: Per W. Norheim (1979) Oral health status in a population in Northern Norway, Acta Odontologica Scandinavica, 37:5, 293-300 To link to this article: http://dx.doi.org/10.3109/00016357909004699
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Oral health status in a population in Northern Norway
PER W. NORHEIM
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Department of Prosthetic Dentistry, Dental Faculty, University of Oslo, Oslo, Norway Norheim, P.W. Oral health status in a population in Northern Norway. Acta Odontol. Scand. 1979,31,293-300 Information concerning oral health status was obtained through a clinical and radiographic examination of 297 persons aged 20-69 years out of a population of 358 persons living in a coastal community in Northern Norway. The oral health was generally poor. 71% had one ore more remaining teeth and the dentulous persons had a mean number of 18 remaining teeth. The mean number of DMF teeth was 27,3, while the mean number of decayed teeth was 4,9 and filled teeth 12,O giving a percent of decayed and filled teeth of 27 and 6 5 respectively. Only every fourth dentulous person had one or more crowns and/or bridge units and 4% of all teeth had been treated endodontically. 41%of the teeth had visible plaque and 56% of the teeth had one ore more gingival margins bleeding after gentle probing. One fourth of all teeth had gingival pockets exceeding 3 mm and 17%of all teeth showed a bone loss of 20% or more. The number of remaining teeth decreased with increasing age and decreasing income and/or social class. In general, women, young people and people with a high socioeconomic status had less caries, better oral hygiene and periodontal condition and had received more restorative dental care than the remaining part of the population.
Key-words: Caries; epidemiology; fixed dental restorations; number of remaining teeth; periodontal condition
P. W. Norheim, Department of Prosthetic Dentistry, Dental Faculty, Box I1 09, Blindern, Oslo 3, Norway
Although there seems to be an increasing interest for survey research within the field of dentistry in Norway, there is still lack of knowledge as to dental conditions in the adult population. Up to now most epidemiologic studies on dental health have been concerned about selected groups (for review see Hansen & Johansen 1976, Hansen 1977). Studies comprising samples representative of larger population groups are scarce and include only a few age groups ( 5 , 8 , 9 , 10, 13,
Received for publication, April 25, 1979
29). In addition, or,] a few oral and social variables have been considered. The purpose of the present study was to report the prevalence of remaining teeth, restorative and endodontic work, the prevalence of caries, periodontal disease and pathologic conditions in the jaws in a population in Northern Norway. Furthermore, the intention was to describe the possible influence of some demografic and socioeconomic factors on the oral health condition in the population.
294
PER W. NORHEIM MATERIAL AND METHODS
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Study population The survey was carried out while the author was dental health officer in the coastal village Lyngseidet in Northern Norway. In the period May 1972 to April 1973,83 % of the total population of 358 persons aged 20-69 participated in the study (24). Due to the high rate of participation and the finding that participants and non-participants had an almost equal number of teeth and dentures, the group studied was considered to be reasonably representative for the whole population. The total family income was registered for each family member. The participants were classified socially on an occupation scale according to the highest ranking family member. This scale comprised three social classes: Class 1 : professionals and executives; Class 2: ”white collar” employees and foremen; Class 3 : ”blue collar” workers (12).
ORAL HEALTH STATUS
Clinical examination The participants were examined by the author at the local Public Dental Service (PDS) clinic at Lyngseidet, the examination sequence was generally at random. Compressed air, a sharp probe and a plane mouth mirror were used for the diagnosis of caries. The probe was replaced after every tenth examination. The assessment of pocket depth was made with a blunt periodontal probe with 2 mm gradations. 32 teeth were used as basis for the examination, except for the periodontal condition where the third molars were excluded. The data were recorded by a trained dental nurse on a precoded chart from which data were transferred directly to punch cards. To control the data handling. all data were punched twice and checks were made to localize unlogical values on the variables.
Radiographic examination A set of 10 periapical radiograms was taken for all participants, including edentulous persons. The projection of the radiograms were standardized by means of Eggen’s film holder (7). In addition, two bitewing radiograms were taken for each participant with teeth in the lateral segments. All radiograms were taken and developed by a trained dental nurse. The radiograms were assessed after and independently of the clinical examination, simultaneously (1 7,20) by the author and a second dentist, employing a viewing box and a magnifying glass.
Caries experience Carious lesions were registered at the clinical examination according to the requirements recommended by WHO (34). Abrasions, attritions, and erosions (26) were not recorded. Clinical caries (6) was registered both as decayed (D) teeth and D tooth surfaces. Fillings were registered both as filled (F) teeth and F tooth surfaces. The overlapping of D and F teeth values, i.e. teeth which were both decayed and filled, was adjusted when the caries experience was calculated according to the DMF teeth Index (16). Teeth which could not be restored were tabulated as roots (RX) (34). In addition to the clinical caries registration both bitewings and periapical radiograms were assessed for caries. Primary proximal caries was recorded when a radiolucent area reached the inner half of the enamel (21). Secondary caries was recorded when a distinct radiolucency was observed at the proximal gingival margin of an existing restoration ( I 1). Carious lesions registered by radiograms were recorded both separately and combined with the clinical caries registration. The number of unreadable proximal surfaces were recorded.
ORAL HEALTH STATUS
Prosthetics
295
PORTION OFTEETH IN PERCENT
The number of crowns and bridge units was recorded. Data concerning complete dentures have been reported previously (25).
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Oral hygiene and periodontal condition The oral hygiene was scored on all four gingival areas for all teeth according to the Plaque Index (PlI) (30) and the gingival condition according to the Gingival Index (GI) (18). However, in the present paper both indices were used in a modified form (2). Thus, plaque was recorded only on tooth surfaces where it was clearly visible, and gingivitis only on gingival margins which bled after gentle probing of the sulcus or pocket area. Periodontal pocket measurements in mm were made on all four gingival areas for all teeth. The periapical radiograms were used to assess marginal bone loss. The percent of mesial and distal bone losses was measured using a special ruler designed by Schei et al. (28). The number of not measurable bone hights was recorded.
Radiographic findings The periapical radiograms were studied in order to determine the number of pathological findings in the jaws. Endodontically treated teeth with and without distinct periapical lesions (I 9) were tabulated separately. Periapical lesions were also registered on teeth without endodontic treatment. Prior to the study the author was trained in the use of the clinical and radiographical criteria presently employed at the Departments of Periodontology, Preventive Dentistry and Oral 'Roentgenology, Dental Faculty, University of Oslo.
PORTION OF PERSONS I N PERCENT, 0 ACCORDING TO AGE AGE (YEARS1
Fig. 1 . Accumulated frequency of the total number of teeth gU = 3876) in the study group (N = 297) according t o age (Lorenz curve).
RESULTS
Number of remaining teeth 71% of the participants had one ore more remaining teeth (Table 1) and the mean number of remaining teeth was 13,l. The dentulous persons alone had a mean number of 18,4 teeth (Table 3 ) and 1,2 roots (a). The number of remaining teeth decreased with increasing age (Fig. 1) and decreasing income and/or social class (Table 1). The finding that men had more remaining teeth than women (Table 1 and 3 ) is spurious due to an overrepresentation of elderly people and people with low socioeconomic status among the women ( 2 3 , 2 5 ) .
Caries experience Variations in the mean DMF teeth according to sex, age, income and social class were
296
PER W. NORHEIM
Table 1. Percentage of persons according to sex, age, income, social class and number of remaining teeth Number of remaining teeth
Number of persons
F
%
1-9 %
10-19 7%
> 20
No 137 160
100 100
21 36
18 17
21 13
40 35
88 124 85
100 100 100
2 20 69
2 29 15
13 26 7
83
Family income (Norw.kr.) < 30 000 30 000-49 000 > 50 000
124 100 73
100 100 100
41 22 18
19 19 11
10 22 19
29 37 52
Social class 1 2 3
37 112 148
100 100 100
19 20 39
3 13 24
22 19 14
57 48 24
Total
297
100
29
17
17
37
None
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Sex Men Women Age W s . ) 20-29 30-49 50-69
%
25 8
Table 2. The dentulous persons: mean number i standarddeviation ( x d . ) of decayed (0) teeth, filled (F) teeth, missing (M)teeth + roots (RX) and the percent of D and F teeth according to sex, age, income and social chss
-
lumber of persons
D teeth f s.d.
x
F teeth X i s.d.
M teeth
x
i
+ RX s.d.
I
I
1
I
DMF teeth D teeth :teeth X i s.d. % %
Sex Men Women
109 104
5,8 f 5 , l 4,1 f 3 5
11,7 t 8,6 12,4 f 8,4
13,4 f 8,2 13,9 f 8,2
27,2 f 3,3 27,4 f 2,7
31 23
63 69
Age (yrs.1 20-29 30-49 50-69
86 100 27
6,s f 5 , s 3,9 f 3,5 3,3 f 3,4
16,6 f 8,9 9.3 f 8,5 6,5 f 7,8
7,9 -t 4,s 16,9f 7,6 18,8 f 8,6
26,4+ 3,l 27,6 f 2,8 26,7 f 2,6
26 26 27
69 63 52
5 ,o
Family income (hrorw. kr.) < 30 000 30 000--49 000 2 50 000 So rial class 1
,. L
3
Total/Mean -__
74 79 60
5,2 4,9 43
4,3 3,9
9,7 f 8,7 11,2 t 8,8 15,7 c 7,8
14,l t 9,O 14,4 f 7,5 11,5 t. 6,5
26,3 c 3,3 27,l t 3,O 28,O f 2,4
29 28 22
55 65 76
30 90 93
4,l t 3,O 4,2 k 3,7 5,9 f 3,9
18,O t 7,6 13,8 i 8,7 8,3 ?r 8,6
9,9 + 5 , 8 12,l f 7,5 16,3 f 8,9
28,2 27,l 27,2
82 70
4,3
12,O * 8 3
13,6 t 8,2
213
4,9
f f
t
f
t
2,8
i
3,l
19 21 38
27,3 k 3,O
21
* 3,O
297
ORAL HEALTH STATUS
Table 3. Mean number o f teeth f s.d., oral hygiene and periodontal condition o f the dentulous persons: percentage of teeth with visible plaque (Pll score 2 and 3), gingival bleeding b y probing (GI score 2 and 3), periodontal pockets of 4-5 mm and marginal bone loss o f 20 % according to sex, age, income and social class. (Plaque, gingival bleeding and periodontal pockets were scored on all four gingival areas of the teeth, while marginal bone loss was measured mesiolly and distally b y means of periapical radiogram
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Percentage of teeth Remaining teeth ff f s.d.
Visible plaque %
Gingival bleeding %
Gingival pockets 4-5 mm
k
darginal bone loss 20 %
Sex Men Women 4ge (yrs.) 20-29 30-49 50-69
18,6 f 8 , l 18,l f 8,2
49 32
58 54
30 17
20 13
24,l f 4,7 14,8 t 7,8 12,4 -f. 7,6
33 47 64
53 58 72
15 35 29
7 28 26
Family income (Norw. kr.) < 30 000 30 000-49 000 > 50 000
17,7 f 9 , l 17,4 2 7,5 20,6 f 7,O
44 41 37
58 55 55
22 24 24
15 17 17
Social class 1 2 3
22,o t 5,7 19,8 f 7,5 15,7 f 8,6
32 37 50
46 54 65
21 22 28
16 16 18
Mean
18,4
41
56
25
17
f
8,2
negligible, while the frequency values and the percent of D and F teeth varied according to these background variables (Table 2). Of the nine percent D surfaces two thirds were located on the proximal surfaces. Half of the proximal carious lesions were secondary caries. One third of the proximal carious lesions were diagnosed only by radiograms, 75 % of these lesions represented secondary caries. The radiograms of four percent of all proximal tooth surfaces were unreadable, mostly in the third molar regions.
Fixed prosthetics Of the 50 people who had one ore more crowns or bridge units (total 195 units) 41 of them belonged to social class 1 or 2.
Oral hygiene and periodontal condition The percentages of teeth with one or more gingival areas with visible plaque (PI1 score 2 and 3) and/or gingival bleeding (G1 score 2 and 3) were 41 and 56 respectively (Table 3). One fourth of all teeth had gingival pockets exceeding 3 mm and 17 % of all teeth had bone loss of 20 % or more. Plaque, gingivitis, gingival pockets and bone loss were most common among men, elderly people and people with low income and/or social class (Table 3). The influence of income and social class on the number of gingival pockets and bone loss was modest, however, also after adjusting for the overrepresentation of middle-aged and elderly people in the high socioeconomic groups. Marginal bone loss could not be measured on 5 % of the tooth surfaces mostly due to overlaps in the canine and second molar regions.
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PER W. NORHEIM
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Radiographic findings
Four percent of all teeth had been treated endodontically, and every sixth of these teeth had periapical lesions. In addition, periapical lesions were seen in one percent of the teeth without endodontic treatment. Three-fourth of all endodontically treated teeth were seen in persons in social class 1 and 2. Twenty-three percent of the study group had pathological conditions in the jaws, only five people had two findings. Root remains were found in 16 % of the participants, impacted teeth in four percent and foreign bodies, cysts and osteosklerosis in one percent respectively.
DISCUSSION
A number of indicators showed a state of general poor oral health in the present population: 1 . Both the proportion of dentulous persons and the mean number of remaining teeth in the total population and among the dentulous persons separately were lower than reported in the few comparable investigations in the Scandinavian countries (3, 5, 9, 10, 15,31,32). 2. The high mean number of DMF teeth (Table 2) was mainly due to the high number of M teeth. This indicated that when the mean number of D teeth (Table 2) was relatively small, it should be seen in connection with the low mean number of remaining teeth. However, this influence of M teeth was adjusted for through the calculation of the percent of D teeth, showing that more than one fourth of all teeth were decayed (Table 2). In addition, the fact that the canes resistent mandibular front teeth are most likely to remain, may also have played a part (1, 9). The low proportion of secondary canes in the present population compared with other populations
Most of the indicators used to measure the oral health status in the present popu3. The general lack of data concerning the frequency of restorative dental care in the Scandinavian countries makes direct comparison with other studies difficult. However, age-specific samples from the present population compared with corresponding groups from other studies indicated that the frequency of fillings, endodontic treatments and crowns and bridges were lower than observed elsewhere in Scandinavia(3,9, 10, 15,31, 32). 4. The oral hygiene and the periodontal condition was similar to that found in corresponding age groups in a study in Sweden (3, 4). However, knowing that pocket formation and bone loss is mainly related to middle-aged and aged people (33), the fair periodontal condition of the present population should be seen partly as a result of the high tooth mortality according to age (Fig. 1). The moderate frequency of pathologic radiographic findings in the jaws in the present study compared with most studies (for review see Lysell 1977) may partly be due to the fact that those studies mostly have been on selected treatment-seeking groups and that orthopantomograms often were used in addition to periapical radiograms. There is reason to believe that the poor oral health in the present population was affected by situational factors such as weak economy, insufficient travelling communications to the dental office and a general lack of dentists (23, 24, 25). These local treatment barriers have been reduced during the last decades, thus explaining some of the great differences in the number of teeth between different age groups (Table 1, Fig. 1). Thus persons aged 20-29 years, representing 35 % of the participants, had as much as 53% of the total number of teeth, while people aged 60-69 years. representing 15% of the group, had only two percent of the total number of teeth.
ORAL HEALTH STATUS
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(4,9) may be related to the low number of F tooth surfaces. lation were related to the sex, age, income and social class of the respondents (Table 1 , 2, 3 and Fig. l), also when interactions between characteristics were adjusted for. Thus the number of remaining teeth decreased with increasing age and decreasing income and/or social class. Furthermore, women, young people and people with high socio-economic status had generally more remaining teeth, less caries, better oral hygiene and periodontal condition and had received more restorative dental care than the remaining part of the population. These observations are in keeping with other studies (27). The dependence of the oral health and the treatment profile as previously reported (23) upon background characteristics such as sex, age, income and social class is probably at least in part, a reflection of the development of public dental health services through three stages: relief of pain, repair, and prevention (14). Thus middle-aged and aged people with low socioeconomic status had the dentist visited mainly for extractions and complete denture services (23). These persons had usually lost all or most of their teeth in young ages (Table 1) and being denture wearers they rarely visited a dentist (25). In contrast, middle-aged and aged people belonging to higher socio-economic groups had visited the dentist more regularly (23). These groups generally had a high number of remaining teeth (Table 1) and were ”heavy consumers” of restorative (Table 2) and periodontal dental care (23). Younger people had received dental treatment at school and had become accustomed to regular preventive and conservative dental treatments. After leaving school, many of these young people seemed to have fallen back to a more irregular treatment attendance. However, the great majority of those with high socioeconomic status remained regular preventive-orientated treatment attenders.
299
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Acta Odontologica Scandinavica Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/iode20
Oral health status in a population in Northern Norway Per W. Norheim
a
a
Department of Prosthetic Dentistry, Dental Faculty, University of Oslo, Oslo, Norway Published online: 23 May 2015.
To cite this article: Per W. Norheim (1979) Oral health status in a population in Northern Norway, Acta Odontologica Scandinavica, 37:5, 293-300 To link to this article: http://dx.doi.org/10.3109/00016357909004699
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions
Oral health status in a population in Northern Norway
PER W. NORHEIM
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Department of Prosthetic Dentistry, Dental Faculty, University of Oslo, Oslo, Norway Norheim, P.W. Oral health status in a population in Northern Norway. Acta Odontol. Scand. 1979,31,293-300 Information concerning oral health status was obtained through a clinical and radiographic examination of 297 persons aged 20-69 years out of a population of 358 persons living in a coastal community in Northern Norway. The oral health was generally poor. 71% had one ore more remaining teeth and the dentulous persons had a mean number of 18 remaining teeth. The mean number of DMF teeth was 27,3, while the mean number of decayed teeth was 4,9 and filled teeth 12,O giving a percent of decayed and filled teeth of 27 and 6 5 respectively. Only every fourth dentulous person had one or more crowns and/or bridge units and 4% of all teeth had been treated endodontically. 41%of the teeth had visible plaque and 56% of the teeth had one ore more gingival margins bleeding after gentle probing. One fourth of all teeth had gingival pockets exceeding 3 mm and 17%of all teeth showed a bone loss of 20% or more. The number of remaining teeth decreased with increasing age and decreasing income and/or social class. In general, women, young people and people with a high socioeconomic status had less caries, better oral hygiene and periodontal condition and had received more restorative dental care than the remaining part of the population.
Key-words: Caries; epidemiology; fixed dental restorations; number of remaining teeth; periodontal condition
P. W. Norheim, Department of Prosthetic Dentistry, Dental Faculty, Box I1 09, Blindern, Oslo 3, Norway
Although there seems to be an increasing interest for survey research within the field of dentistry in Norway, there is still lack of knowledge as to dental conditions in the adult population. Up to now most epidemiologic studies on dental health have been concerned about selected groups (for review see Hansen & Johansen 1976, Hansen 1977). Studies comprising samples representative of larger population groups are scarce and include only a few age groups ( 5 , 8 , 9 , 10, 13,
Received for publication, April 25, 1979
29). In addition, or,] a few oral and social variables have been considered. The purpose of the present study was to report the prevalence of remaining teeth, restorative and endodontic work, the prevalence of caries, periodontal disease and pathologic conditions in the jaws in a population in Northern Norway. Furthermore, the intention was to describe the possible influence of some demografic and socioeconomic factors on the oral health condition in the population.
294
PER W. NORHEIM MATERIAL AND METHODS
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Study population The survey was carried out while the author was dental health officer in the coastal village Lyngseidet in Northern Norway. In the period May 1972 to April 1973,83 % of the total population of 358 persons aged 20-69 participated in the study (24). Due to the high rate of participation and the finding that participants and non-participants had an almost equal number of teeth and dentures, the group studied was considered to be reasonably representative for the whole population. The total family income was registered for each family member. The participants were classified socially on an occupation scale according to the highest ranking family member. This scale comprised three social classes: Class 1 : professionals and executives; Class 2: ”white collar” employees and foremen; Class 3 : ”blue collar” workers (12).
ORAL HEALTH STATUS
Clinical examination The participants were examined by the author at the local Public Dental Service (PDS) clinic at Lyngseidet, the examination sequence was generally at random. Compressed air, a sharp probe and a plane mouth mirror were used for the diagnosis of caries. The probe was replaced after every tenth examination. The assessment of pocket depth was made with a blunt periodontal probe with 2 mm gradations. 32 teeth were used as basis for the examination, except for the periodontal condition where the third molars were excluded. The data were recorded by a trained dental nurse on a precoded chart from which data were transferred directly to punch cards. To control the data handling. all data were punched twice and checks were made to localize unlogical values on the variables.
Radiographic examination A set of 10 periapical radiograms was taken for all participants, including edentulous persons. The projection of the radiograms were standardized by means of Eggen’s film holder (7). In addition, two bitewing radiograms were taken for each participant with teeth in the lateral segments. All radiograms were taken and developed by a trained dental nurse. The radiograms were assessed after and independently of the clinical examination, simultaneously (1 7,20) by the author and a second dentist, employing a viewing box and a magnifying glass.
Caries experience Carious lesions were registered at the clinical examination according to the requirements recommended by WHO (34). Abrasions, attritions, and erosions (26) were not recorded. Clinical caries (6) was registered both as decayed (D) teeth and D tooth surfaces. Fillings were registered both as filled (F) teeth and F tooth surfaces. The overlapping of D and F teeth values, i.e. teeth which were both decayed and filled, was adjusted when the caries experience was calculated according to the DMF teeth Index (16). Teeth which could not be restored were tabulated as roots (RX) (34). In addition to the clinical caries registration both bitewings and periapical radiograms were assessed for caries. Primary proximal caries was recorded when a radiolucent area reached the inner half of the enamel (21). Secondary caries was recorded when a distinct radiolucency was observed at the proximal gingival margin of an existing restoration ( I 1). Carious lesions registered by radiograms were recorded both separately and combined with the clinical caries registration. The number of unreadable proximal surfaces were recorded.
ORAL HEALTH STATUS
Prosthetics
295
PORTION OFTEETH IN PERCENT
The number of crowns and bridge units was recorded. Data concerning complete dentures have been reported previously (25).
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Oral hygiene and periodontal condition The oral hygiene was scored on all four gingival areas for all teeth according to the Plaque Index (PlI) (30) and the gingival condition according to the Gingival Index (GI) (18). However, in the present paper both indices were used in a modified form (2). Thus, plaque was recorded only on tooth surfaces where it was clearly visible, and gingivitis only on gingival margins which bled after gentle probing of the sulcus or pocket area. Periodontal pocket measurements in mm were made on all four gingival areas for all teeth. The periapical radiograms were used to assess marginal bone loss. The percent of mesial and distal bone losses was measured using a special ruler designed by Schei et al. (28). The number of not measurable bone hights was recorded.
Radiographic findings The periapical radiograms were studied in order to determine the number of pathological findings in the jaws. Endodontically treated teeth with and without distinct periapical lesions (I 9) were tabulated separately. Periapical lesions were also registered on teeth without endodontic treatment. Prior to the study the author was trained in the use of the clinical and radiographical criteria presently employed at the Departments of Periodontology, Preventive Dentistry and Oral 'Roentgenology, Dental Faculty, University of Oslo.
PORTION OF PERSONS I N PERCENT, 0 ACCORDING TO AGE AGE (YEARS1
Fig. 1 . Accumulated frequency of the total number of teeth gU = 3876) in the study group (N = 297) according t o age (Lorenz curve).
RESULTS
Number of remaining teeth 71% of the participants had one ore more remaining teeth (Table 1) and the mean number of remaining teeth was 13,l. The dentulous persons alone had a mean number of 18,4 teeth (Table 3 ) and 1,2 roots (a). The number of remaining teeth decreased with increasing age (Fig. 1) and decreasing income and/or social class (Table 1). The finding that men had more remaining teeth than women (Table 1 and 3 ) is spurious due to an overrepresentation of elderly people and people with low socioeconomic status among the women ( 2 3 , 2 5 ) .
Caries experience Variations in the mean DMF teeth according to sex, age, income and social class were
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PER W. NORHEIM
Table 1. Percentage of persons according to sex, age, income, social class and number of remaining teeth Number of remaining teeth
Number of persons
F
%
1-9 %
10-19 7%
> 20
No 137 160
100 100
21 36
18 17
21 13
40 35
88 124 85
100 100 100
2 20 69
2 29 15
13 26 7
83
Family income (Norw.kr.) < 30 000 30 000-49 000 > 50 000
124 100 73
100 100 100
41 22 18
19 19 11
10 22 19
29 37 52
Social class 1 2 3
37 112 148
100 100 100
19 20 39
3 13 24
22 19 14
57 48 24
Total
297
100
29
17
17
37
None
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Sex Men Women Age W s . ) 20-29 30-49 50-69
%
25 8
Table 2. The dentulous persons: mean number i standarddeviation ( x d . ) of decayed (0) teeth, filled (F) teeth, missing (M)teeth + roots (RX) and the percent of D and F teeth according to sex, age, income and social chss
-
lumber of persons
D teeth f s.d.
x
F teeth X i s.d.
M teeth
x
i
+ RX s.d.
I
I
1
I
DMF teeth D teeth :teeth X i s.d. % %
Sex Men Women
109 104
5,8 f 5 , l 4,1 f 3 5
11,7 t 8,6 12,4 f 8,4
13,4 f 8,2 13,9 f 8,2
27,2 f 3,3 27,4 f 2,7
31 23
63 69
Age (yrs.1 20-29 30-49 50-69
86 100 27
6,s f 5 , s 3,9 f 3,5 3,3 f 3,4
16,6 f 8,9 9.3 f 8,5 6,5 f 7,8
7,9 -t 4,s 16,9f 7,6 18,8 f 8,6
26,4+ 3,l 27,6 f 2,8 26,7 f 2,6
26 26 27
69 63 52
5 ,o
Family income (hrorw. kr.) < 30 000 30 000--49 000 2 50 000 So rial class 1
,. L
3
Total/Mean -__
74 79 60
5,2 4,9 43
4,3 3,9
9,7 f 8,7 11,2 t 8,8 15,7 c 7,8
14,l t 9,O 14,4 f 7,5 11,5 t. 6,5
26,3 c 3,3 27,l t 3,O 28,O f 2,4
29 28 22
55 65 76
30 90 93
4,l t 3,O 4,2 k 3,7 5,9 f 3,9
18,O t 7,6 13,8 i 8,7 8,3 ?r 8,6
9,9 + 5 , 8 12,l f 7,5 16,3 f 8,9
28,2 27,l 27,2
82 70
4,3
12,O * 8 3
13,6 t 8,2
213
4,9
f f
t
f
t
2,8
i
3,l
19 21 38
27,3 k 3,O
21
* 3,O
297
ORAL HEALTH STATUS
Table 3. Mean number o f teeth f s.d., oral hygiene and periodontal condition o f the dentulous persons: percentage of teeth with visible plaque (Pll score 2 and 3), gingival bleeding b y probing (GI score 2 and 3), periodontal pockets of 4-5 mm and marginal bone loss o f 20 % according to sex, age, income and social class. (Plaque, gingival bleeding and periodontal pockets were scored on all four gingival areas of the teeth, while marginal bone loss was measured mesiolly and distally b y means of periapical radiogram
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Percentage of teeth Remaining teeth ff f s.d.
Visible plaque %
Gingival bleeding %
Gingival pockets 4-5 mm
k
darginal bone loss 20 %
Sex Men Women 4ge (yrs.) 20-29 30-49 50-69
18,6 f 8 , l 18,l f 8,2
49 32
58 54
30 17
20 13
24,l f 4,7 14,8 t 7,8 12,4 -f. 7,6
33 47 64
53 58 72
15 35 29
7 28 26
Family income (Norw. kr.) < 30 000 30 000-49 000 > 50 000
17,7 f 9 , l 17,4 2 7,5 20,6 f 7,O
44 41 37
58 55 55
22 24 24
15 17 17
Social class 1 2 3
22,o t 5,7 19,8 f 7,5 15,7 f 8,6
32 37 50
46 54 65
21 22 28
16 16 18
Mean
18,4
41
56
25
17
f
8,2
negligible, while the frequency values and the percent of D and F teeth varied according to these background variables (Table 2). Of the nine percent D surfaces two thirds were located on the proximal surfaces. Half of the proximal carious lesions were secondary caries. One third of the proximal carious lesions were diagnosed only by radiograms, 75 % of these lesions represented secondary caries. The radiograms of four percent of all proximal tooth surfaces were unreadable, mostly in the third molar regions.
Fixed prosthetics Of the 50 people who had one ore more crowns or bridge units (total 195 units) 41 of them belonged to social class 1 or 2.
Oral hygiene and periodontal condition The percentages of teeth with one or more gingival areas with visible plaque (PI1 score 2 and 3) and/or gingival bleeding (G1 score 2 and 3) were 41 and 56 respectively (Table 3). One fourth of all teeth had gingival pockets exceeding 3 mm and 17 % of all teeth had bone loss of 20 % or more. Plaque, gingivitis, gingival pockets and bone loss were most common among men, elderly people and people with low income and/or social class (Table 3). The influence of income and social class on the number of gingival pockets and bone loss was modest, however, also after adjusting for the overrepresentation of middle-aged and elderly people in the high socioeconomic groups. Marginal bone loss could not be measured on 5 % of the tooth surfaces mostly due to overlaps in the canine and second molar regions.
298
PER W. NORHEIM
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Radiographic findings
Four percent of all teeth had been treated endodontically, and every sixth of these teeth had periapical lesions. In addition, periapical lesions were seen in one percent of the teeth without endodontic treatment. Three-fourth of all endodontically treated teeth were seen in persons in social class 1 and 2. Twenty-three percent of the study group had pathological conditions in the jaws, only five people had two findings. Root remains were found in 16 % of the participants, impacted teeth in four percent and foreign bodies, cysts and osteosklerosis in one percent respectively.
DISCUSSION
A number of indicators showed a state of general poor oral health in the present population: 1 . Both the proportion of dentulous persons and the mean number of remaining teeth in the total population and among the dentulous persons separately were lower than reported in the few comparable investigations in the Scandinavian countries (3, 5, 9, 10, 15,31,32). 2. The high mean number of DMF teeth (Table 2) was mainly due to the high number of M teeth. This indicated that when the mean number of D teeth (Table 2) was relatively small, it should be seen in connection with the low mean number of remaining teeth. However, this influence of M teeth was adjusted for through the calculation of the percent of D teeth, showing that more than one fourth of all teeth were decayed (Table 2). In addition, the fact that the canes resistent mandibular front teeth are most likely to remain, may also have played a part (1, 9). The low proportion of secondary canes in the present population compared with other populations
Most of the indicators used to measure the oral health status in the present popu3. The general lack of data concerning the frequency of restorative dental care in the Scandinavian countries makes direct comparison with other studies difficult. However, age-specific samples from the present population compared with corresponding groups from other studies indicated that the frequency of fillings, endodontic treatments and crowns and bridges were lower than observed elsewhere in Scandinavia(3,9, 10, 15,31, 32). 4. The oral hygiene and the periodontal condition was similar to that found in corresponding age groups in a study in Sweden (3, 4). However, knowing that pocket formation and bone loss is mainly related to middle-aged and aged people (33), the fair periodontal condition of the present population should be seen partly as a result of the high tooth mortality according to age (Fig. 1). The moderate frequency of pathologic radiographic findings in the jaws in the present study compared with most studies (for review see Lysell 1977) may partly be due to the fact that those studies mostly have been on selected treatment-seeking groups and that orthopantomograms often were used in addition to periapical radiograms. There is reason to believe that the poor oral health in the present population was affected by situational factors such as weak economy, insufficient travelling communications to the dental office and a general lack of dentists (23, 24, 25). These local treatment barriers have been reduced during the last decades, thus explaining some of the great differences in the number of teeth between different age groups (Table 1, Fig. 1). Thus persons aged 20-29 years, representing 35 % of the participants, had as much as 53% of the total number of teeth, while people aged 60-69 years. representing 15% of the group, had only two percent of the total number of teeth.
ORAL HEALTH STATUS
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(4,9) may be related to the low number of F tooth surfaces. lation were related to the sex, age, income and social class of the respondents (Table 1 , 2, 3 and Fig. l), also when interactions between characteristics were adjusted for. Thus the number of remaining teeth decreased with increasing age and decreasing income and/or social class. Furthermore, women, young people and people with high socio-economic status had generally more remaining teeth, less caries, better oral hygiene and periodontal condition and had received more restorative dental care than the remaining part of the population. These observations are in keeping with other studies (27). The dependence of the oral health and the treatment profile as previously reported (23) upon background characteristics such as sex, age, income and social class is probably at least in part, a reflection of the development of public dental health services through three stages: relief of pain, repair, and prevention (14). Thus middle-aged and aged people with low socioeconomic status had the dentist visited mainly for extractions and complete denture services (23). These persons had usually lost all or most of their teeth in young ages (Table 1) and being denture wearers they rarely visited a dentist (25). In contrast, middle-aged and aged people belonging to higher socio-economic groups had visited the dentist more regularly (23). These groups generally had a high number of remaining teeth (Table 1) and were ”heavy consumers” of restorative (Table 2) and periodontal dental care (23). Younger people had received dental treatment at school and had become accustomed to regular preventive and conservative dental treatments. After leaving school, many of these young people seemed to have fallen back to a more irregular treatment attendance. However, the great majority of those with high socioeconomic status remained regular preventive-orientated treatment attenders.
299
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