According to the Statistics Korea, it has been reported that Korea entered an aging society in 2005 with 7.2% of the population aged ≥65 years. Additionally, it has been predicted that the Korean society will become an aged society in 2022, with the older adult population surpassing 14% of the total population. In addition, it will become a super-aged society in 2032, with the older adult population comprising >20% of the total population. The rate of aging of the older adult population in Korea is considerably faster than that of the advanced countries. These results signified that Korea is in urgent need of preparation for an aging society and must prepare coping measures in advance. Therefore, as the health and welfare of the older adult population has emerged as a new social problem, health problems of the older adult population, focusing on their general or mental health, has garnered a considerable degree of attention. However, research on the oral conditions of the older adult population is currently lacking.

The condition of the teeth which influences digestion and nutrition is the root of health in older adults. Therefore, oral hygiene is an essential element that indicates health of older adults. However, the overall oral health condition of Korea’s older adult population is generally considered poor owing to low examination rates because of economic reasons even when oral treatment is necessary due to passive treatment when compared with that of diseases that directly influence life [1]. In addition, Korea’s older adult population frequently experiences dental caries and periodontal diseases of the oral cavity. Therefore, these two major oral diseases are the main causes that destroy oral health in the older adult population. However, education on the prevention of dental caries and periodontal diseases, general oral health education, and early oral health care are not properly provided; in addition, there is a paucity of research on this topic [2]. Furthermore, the reality of a demographically growing older adult age group and an accumulation of oral diseases with a prolonged average life expectancy may lead to a lengthened period of contracting and experiencing oral diseases. However, the demand for oral care continues to grow despite of the absence or lack of economic ability in the older adult population. Most oral diseases are preventable. Unlike other conditions, an individual’s voluntary actions are extremely important, and oral health behavior plays an essential role. Therefore, considering socioeconomic costs and conditions, we believe that individuals should voluntarily protect one’s oral health through oral hygiene education and participation in the oral management programs [3] and should promote their physical health and quality of life.

This study was conducted to analyze the practical effect of a continuous oral management program of a periodic oral health education [4] in an aging society on the older adults at home who use Korea’s public health centers, promote individual oral health of the older adults at home who use public health centers [5], accentuate the importance of improving continuous oral management programs in oral health education, and invigorate oral health education in the local communities.

1. Research method

Artificial lighting and natural lighting were used as tools for oral examination of the oral conditions using dental mirrors, probes, and tweezers. The classification included the number of existing teeth and decayed teeth with observable dental caries, missing teeth, filled teeth (World Health Organization [WHO] judgment standard), remaining teeth, which included functional teeth and teeth requiring extraction, and functioning teeth which included teeth with filling, fixed prostheses (brass and porcelain crowns), and natural teeth that retain mastication function (Sunbong Yang, 2006). The dental plaque was determined by the degree of dental plaque, the tongue coating [6] was determined by the degree of tongue plaque, and the denture contamination was determined by the degree of denture contamination. These were classified into three stages (mild, moderate, and severe). Regarding the O’Leary’s [7] dental plaque adhesion rate (Harris, Norman and Garcia- Godoy, Franklin Primary Preventive Dentistry), (WHO standard), the surface of each tooth was classified into mesial, central (buccal or lingual), and distal to determine the score after coloring the tooth surface using a disclosing solution.

The purpose of this study was as follows:

Figure 1. Research framework.

1. To compare and analyze oral care among older adults before and after participating in the oral health education.

2. To investigate the oral hygiene improvement through the participation in the continuous oral management program in oral health education.

For 3 months from April 1 to June 30, 2019, 104 older adults at home, at a public health center located in Daegu, were classified into a control group and management group according to days of the week, respectively. Among them, 97 patients were included as study subjects for the final analysis, which excluded 7 patients who did not complete the oral health education continuous oral management program.

1. Before participating in the oral health education continuous oral management program

The number of carious teeth of the subjects was 0.15 in the control group and 0.24 in the intervention group; the number of missing teeth was 14.6 and 13.5 in the control group and intervention group, respectively; the number of filled teeth was 6.6 and 6.9 in the control group and intervention group, respectively; the number of remaining teeth was 17.5 and 18.5 in the control group and intervention group, respectively; the number of functional teeth was 17.1 and 18.2 in the control group and intervention group, respectively; and there was no significant intergroup difference before the participation in the oral health education continuous oral management program (Table 1).

Table 1 . Distribution of carious, missing, filling, remaining, and functioning teeth

Variables	Control group (N=47)	Intervention group (N=50)	Total (N=97)	p-value
Carious teeth	0.15±0.42	0.24±0.63	0.20±0.53	0.403
Missing teeth	14.6±10.2	13.5±9.0	14.0±9.5	0.596
Filled teeth	6.6±5.5	6.9±4.7	6.8±5.1	0.816
Remaining teeth	17.5±10.1	18.5±9.0	18.0±9.5	0.610
Functioning teeth	17.1±10.3	18.2±9.0	17.7±9.6	0.557

Examination of the oral hygiene status of the subjects revealed that the proportion of large amount of food residue was 46.8% in the control group whereas that of the intervention group was 56.0%, which showed a statistically higher result in the intervention group (p<0.05). Additionally, the proportion of the degree of contamination of the dentures or teeth was 38.3% in the control group while that of the intervention group was 52.0%, which showed a significantly higher result in the intervention group (p<0.05). As for the tongue plaque, the proportion in the control group was 40.4% whereas that of the intervention group was 44.0%, which showed the presence of a large amount of tongue plaque in both groups (Table 2).

Table 2 . Distribution of oral hygiene status

Variables	Control group (N=47)	Intervention group (N=50)	Total (N=97)	p-value
Dental plague				0.028
Mild	12 (25.5)	9 (18.0)	15 (15.5)
Moderate	13 (27.7)	13 (26.0)	32 (33.0)
Severe	22 (46.8)	28 (56.0)	50 (51.5)
Tongue coating				0.078
Mild	14 (29.8)	6 (12.0)	20 (20.6)
Moderate	14 (29.8)	22 (44.0)	36 (37.1)
Severe	19 (40.4)	22 (44.0)	41 (42.3)
Denture contamination				0.018
Mild	11 (23.4)	9 (18.0)	13 (13.4)
Moderate	18 (38.3)	15 (30.0)	40 (41.2)
Severe	18 (38.3)	26 (52.0)	44 (45.4)

The dental plaque score of the subjects was 79.5 points in the control group and 82.1 points in the intervention group, which showed that the intervention group had scores higher than the control group. However, this result was not statistically significant (Table 3).

Table 3 . Change of oral hygiene status after follow-up

Variables	Control group (N=47)	Intervention group (N=50)	Total (N=97)	p-value
Score of dental plague	79.5±15.1	82.1±15.2	80.8±15.1	0.395

2. After the participation in the oral health education continuous oral management program

After their participation in the oral health education continuous oral management program, the food residue, tongue plaque, and degree of contaminated dentures or teeth improved from 94% to 18%, 88% to 22%, and 96% to 38%, respectively, thereby showing a significant improvement in the management group after their participation in the oral health education continuous oral management program (Table 4).

Table 4 . Change of oral hygiene status after follow-up

Variables	Pretest			Posttest		p-value	p-value
	Mild	Moderate		Mild	Moderate
Dental plague
Control group	25.5	74.5		29.8	70.2	0.500	0.001
Intervention group	6.0	94.0		82.0	18.0	0.001
Tongue coating
Control group	29.8	70.2		29.8	70.2	1.000	0.001
Intervention group	12.0	88.0		78.0	22.0	0.001
Denture contamination
Control group	23.4	76.6		25.5	74.5	0.470	0.001
Intervention group	4.0	96.0		62.0	38.0	0.001

The dental plaque score decreased by 37.3 points in the management group (p<0.001) after their participation in the oral health educational continuous oral management program. However, only a 0.83-point decrease in the dental plaque adhesion was observed in the control group. After controlling the dental plaque score before the implementation of the oral health educational continuous oral management program, the difference in the effect was examined, This showed a significant difference between the management and control groups (p<0.001) (Table 5).

Table 5 . Mean change of dental plague score after follow-up

Variables	Pretest	Posttest	Change	p-value	p-value
Score of dental plague
Control group	79.5±15.1	78.6±15.0	0.83	0.063	0.001
Intervention group	82.1±15.2	44.8±17.6	37.3	0.001

Korea has entered an aging society in which the proportion of the older adult population aged ≥65 years in the total population has gradually increased as the average life expectancy has been prolonged as a result of developments in medicine and improvement of dietary habits [4]. This has resulted in a recent rise in social problems including those related to the welfare of the older adult patients. Additionally, the trend of an aging population to the prolongation of the average life expectancy is burdening their families owing to the need to for the older adult patients.

Effective oral health education should provide patients with detailed information and principles to guide and motivate them to adopt the appropriate personal oral care. In addition, oral health education should not only convey simple knowledge regarding the prevention of dental and oral diseases to patients but also motivate them to change their attitudes. Furthermore, this form of education should guide them in the direction of taking voluntary actions to solve specific oral health problems and make them realize the importance of oral health care through education.

The older adults who are subjects in the visiting health project appeared to be more exposed to risk factors of periodontal disease. Patients with high blood pressure, diabetes, poor mobility, or arthritis were more likely to neglect oral care.

We believed that it is essential to develop and gradually improve an oral hygiene management program for the oral health of the older adult population focusing on prevention.

No potential conflict of interest relevant to this article was reported.