Implants are considered the first priority when choosing a treatment method for missing teeth. In addition, recently, short treatment times, short treatment periods, and safety through digital implant technology have increased, indicating high preference for patients. However, as the number of implant procedures increases, the number of failure cases due to inflammation of the tissues around the implant continues to increase.

Inflammation around implants is known to have similar types and components of bacteria that cause periodontitis [1], the best treatment to minimize the failure rate of implants is to dental plaque control in the same way as the periodontal disease prevention method. Accordingly, as the prevalence of implants increases in the dental community, interest in prevention-oriented management programs is increasing so that patients can recognize the need for dental plaque control and cultivate the ability to do oral management on their own. Looking at previous studies related to this, researcher Park and researcher Han [2] reported the effect of reduction of Peri-implantitis through professional tooth cleaning and plaque control, and Ma [3] reported that it should continue to be performed at regular intervals depending on the oral condition of patients through a preventive management program using professional mechanical tooth washing (PMTC) [4] . In addition, in a previous paper, the author reported the effectiveness of the PMTC-centered prevention management program and the importance of re-education every three months was reported, and it has been reported that when applying a PMTC-centered preventive management program to patients undergoing implant procedures, the learning period that can induce differentiation of oral health education content and oral hygiene management attitude should be considered [5]. However, no studies have been reported to analyze the compliance of implant patients by the preventive management program applying PMTC, which is effective in dental plaque control.

Compliance with treatment [6] is defined as the degree to which it responds to medical or health and related advice. Therefore, this study reports significant results of statistical analysis of the relationship between various local factors that are expected to affect compliance with preventive management programs operated by implant prosthetic patients to induce and improve oral hygiene through a three-year retrospective study.

1. Materials

This study was approved by the Life Ethics Committee of Gimcheon University (approval No. GU-202302-HRc-01-01-P). From December 2018 to November 2021, 69 patients who visited the oral prevention management office of Busan Dental Clinic and received oral care at least once according to the planned preventive management program with at least one implant prosthesis. In addition, data were collected through a paper medical record system and radiographs, and the following patients were excluded from professional oral care.

(1) A person with a number of cavities requiring endodontic treatment

(2) A person with periodontal disease that has progressed to the loss of alveolar bone in general

2. Method

This study collected basic data on the general characteristics, etc. of subjects through Paper Medical Records. The subjects were patients who received oral care through a preventive management program using PMTC at least once within the study period. The prevention management program operation method is as follows.

(1) Patients enrolled in the program visit the dental clinic for oral care on a monthly basis.

(2) Continuous management is performed every 3 to 6 months depending on the degree of improvement in oral hygiene of the patient.

(3) In order to evaluate oral health changes every time patients visit, the dental plaque index and gingivitis index are measured, and PMTC is performed.

(4) In order to recognize the importance of oral care, the activity of oral bacteria is confirmed through a phase contrast microscopy at the first time.

(5) If necessary, appropriate tooth brushing methods suitable for individual oral conditions, explanations and practices on how to use oral hygiene products are conducted.

(6) The evaluation score (dental plaque index, gingivitis index) for each visit is explained directly to the patient and reconfirmed through text message transmission.

The compliance analysis method was revised and supplemented by referring to the previous papers [5,7], the number of implants and the location of implantation were investigated through panoramic images. The degree of compliance with the preventive management program was classified into a complete compliance group if it was more than 11 times, incomplete compliance group if it was more than 3 times and less than 10 times more, and non-compliance group if it was less than 6 times (Table 1).

Table 1 . Distribution of patients according to compliance with preventive management program

Groups	n	%
Non-compliance	22	31.9
Incomplete compliance	12	17.4
Complete compliance	35	50.7
Total	69	100.0

3. Data analysis

SPSS Statistics ver.18.0 for Window (IBM Corp., Armonk, NY, USA) was used for statistical analysis of the collected data, and the statistical significance level was set to p=0.05. The Kaplan-Myer method was used to analyze the persistence of a three-year preventive management program of a total of 69 people. In addition, in order to identify factors related to the compliance of the preventive management program, the difference in compliance according to the general characteristics and the location of implant retention was analyzed by chi-square test and the relationship between the compliance of the preventive management program, the number of implants, and the smoking and management period was conducted through Pearson's correlation analysis.

1. Preventive management program persistence rate analysis

As a result of analyzing the duration rate according to the management period of the preventive management program, the persistence rate at 1 to 3 months was 49.3%, and 35 of the total subjects were found to have stopped management at 1 to 3 months or received only 3 management times. And as a result of analyzing the cumulative persistence rate according to the management period of the subject who has been managed the preventive management program more than once using the Kaplan-Meier method, the cumulative persistence rates for 6 months, 12 months, 24 months, and 36 months were 44.9%, 41.6%, 37.3%, and 23.1%, respectively, indicating that 58.4% of patients discontinued after one year (Table 2).

Table 2 . Life table analysis for preventive management program persistence rate

Period (months)	A	B	C	PRP (%)	CPR (%)
1-3	69	0	35	49.3	49.3
4-6	34	1	3	91.0	44.9
7-12	30	5	2	92.7	41.6
13-18	23	3	0	100.0	41.6
19-24	20	1	2	89.7	37.3
25-30	17	0	3	82.4	30.8
31-36	14	12	2	75.0	23.1
Total		22	47	31.9	23.1

PRP: persistence Rate in Period, CPR: Cumulative persistence Rate. A: No. of patients before the current time, B: No. of patients completed oral care, C: No. of patients discontinued oral care.

2. Compliance according to general characteristic factors

As a result of examining the characteristic factors that are expected to affect the compliance of the preventive management program, the age group that received the most professional oral care was in their 60s and older, accounting for 53.6% of all subjects, among them, 18 patients (51.4%) were in the fully compliant group (p>0.05). In addition, the higher the number of implants, the higher the compliance with oral care (p<0.05), and in smoking, the higher the proportion of non-smokers (62.3%) received oral care than smokers (37.7%), and in the non-compliance group, the higher the compliance with oral care. In addition, in the complete compliant group, the proportions of smokers and non-smokers showed a slight difference of 51.4% and 48.6%, respectively (p<0.05) (Table 3).

Table 3 . Compliance according to patient characteristics factors

Factors	Range	Non-compliance	Incomplete compliance	Complete compliance	Total	p-value
Gender	Male	9 (40.9)	7 (58.3)	19 (54.3)	35 (50.7)	.521
	Female	13 (59.1)	5 (41.7)	16 (45.7)	34 (49.3)
Age	≤39	2 (9.1)	0 (0.0)	1 (2.9)	3 (4.3)	.745
	40 to ≤49	3 (13.6)	2 (16.7)	4 (11.4)	9 (13.0)
	50 to ≤59	6 (27.3)	2 (16.7)	12 (34.3)	20 (29.0)
	≥60	11 (50.0)	8 (66.7)	18 (51.4)	37 (53.6)
Number of Implants	1-2	6 (27.3)	1 (8.3)	1 (2.9)	8 (11.6)	.003*
	3-4	7 (31.8)	0 (0.0)	7 (20.0)	14 (20.3)
	5-6	3 (13.6)	0 (0.0)	7 (20.0)	10 (14.5)
	7 over	6 (27.3)	11 (91.7)	20 (57.1)	37 (53.6)
Smoking	Yes	3 (13.6)	5 (41.7)	18 (51.4)	26 (37.7)	.016*
	No	19 (86.4)	7 (58.3)	17 (48.6)	43 (62.3)
	Total	22 (100.0)	12 (100.0)	35 (100.0)	69 (100.0)

Values are presented as number (%). Statistically significant differences by chi-square test at a＝0.05*.

3. Compliance according to implant location

As a result of analyzing the area where the study subjects received the implant procedure, it was found that 60 people (87%) had maxillary posterior and mandible posterior with procedure, 38 people (55.1%) had maxillary anterior with procedure and 16 people (23.2%) had mandible anterior with procedure. In addition, in the compliance classification according to implant placement location, the complete compliance group showed the highest compliance among patients treated with maxillary anterior (p<0.05), maxillary posterior (p<0.05), and mandible posterior (p>0.05) (Table 4).

Table 4 . Comparison of compliance according to implantation location

Jaw	Area	Non-compliance	Incomplete compliance	Complete compliance	Total	p-value
Maxillary anterior
	Yes	3 (13.6)	8 (66.7)	27 (77.1)	38 (55.1)	<0.001
	No	19 (86.4)	4 (33.3)	8 (22.9)	31 (44.9)
posterior
	Yes	16 (72.7)	12 (100.0)	32 (91.4)	60 (87.0)	.042*
	No	6 (27.3)	0 (0.0)	3 (8.6)	9 (13.0)
Mandible anterior
	Yes	3 (13.6)	5 (41.7)	8 (22.9)	16 (23.2)	.180
	No	19 (86.4)	7 (58.3)	27 (77.1)	53 (76.8)
posterior
	Yes	19 (86.4)	11 (91.7)	30 (85.7)	60 (87.0)	.865
	No	3 (13.6)	1 (8.3)	5 (14.3)	9 (13.0)
	Total	22 (100.0)	12 (100.0)	35 (100.0)	69 (100.0)

Values are presented as number (%). Statistically significant differences by chi-square test at α＝0.05*.

4. Correlation between compliance with preventive management programs, number of implants, smoking status, and management period

As a result of analyzing the correlation between the compliance of the preventive management program, the number of implants, smoking status, and oral care period, compliance showed a strong positive correlation with management period (p<0.01), positive correlation with the number of implants (p<0.01), and negative correlation with smoking (p<0.01) (Table 5).

Table 5 . Correlation between compliance, number of implants, smoking and management period

Category	Compliance	Number of Implants	Smoking	Period
Compliance	1
Number of Implants	.339**	1
Smoking	−.340**	−.092	1
Period	.706**	.114	−.139	1

Statistically significant differences by the Pearson correlation coefficient at α＝0.01**.

To maintain implants for a long time, dental plaque control management is essential. Therefore, as the supply of implants increases in dental clinics, there is a trend of interest in preventive oral care programs.

In the preventive management program, dental plaque control is the core, and it is important to be regularly managed according to the patient's oral hygiene, so the patient's compliance should also be high. Therefore, this study aims to examine the relationship between various local factors that are expected to affect the compliance of patients managed by PMTC-centered preventive management programs after implantation as a three-year retrospective study.

First of all, the persistence rate of the preventive management program was defined as the percentage of patients who were continuously managed until the patient discontinued the management program. In this study, the 3-year persistence rate for the preventive management program for 69 patients was 31.9%, and the cumulative persistence rate was 23.1%. And the proportion of patients who were discontinued during the first year was 58.4%. This is similar to the result that in the preceding paper [7,8], the rate of discontinuation of maintenance periodontal treatment patients during the first year was the highest. Many researchers [5,9,10] argued the importance of systematic oral health education and repetitive tooth brushing lessons as a way to induce a change in an individual's attitude toward oral care. However, 50.7 percent of the total subjects were stopped management within three months. This reason is thought to be due to the lack of motivation for patients to change their perception of the importance of oral care and to have a willingness to practice. Therefore, Lee and Cho [11] said that it is important to inform patients of detailed information and principles to motivate patients. Therefore, in addition to the phase difference microscope used to recognize the importance of oral care, as suggested by Mendoza et al. [8], methods such as lowering the fee and making patients pay in advance so that they have regular visiting habits are considered. In addition, a method of motivating practice by informing the results of the evaluation of the oral hygiene status of patients mentioned in the author's study [4] through text is also an issue to be considered.

As a result of examining the characteristic factors that are expected to affect the compliance of the preventive management program, the age group that received the most professional oral care was in their 60s or older, accounting for 53.6% of all subjects. And even in the complete compliance group, it was the highest at 51.4% in the group over 60s (p>0.05). However, there was no statistical significance. The Health Insurance Review and Assessment Service said the number of implant patients has been increasing since 2018 as the burden of implants for senior citizens aged 65 or older has eased from 50% to 30%, and the number of implant surgery patients aged 65 to 69 has been 348,637 in 2020 [12]. From this point of view, it is believed that the increase in dental implant procedures due to the expansion of health insurance coverage over the age of 65 has raised interest in oral care for those in their 60s and older, who are vulnerable to oral care.

Of the total subjects of this study, 37 (53.6%) were found to have 7 or more implants. In addition, in the compliance classification, 35 of the total subjects were complete compliant, among them, 20 patients (57.1%) had 7 or more implants (p<0.05). As the number of implants increases, interest in oral care increases, and these results are explained through reports presented in other studies. Jo et al. [13] reported that the higher the number of implants, the relatively higher the dental plaque index for teeth, and there is also a study report [5] that the smaller the number of implants, the better the oral hygiene condition. Therefore, the subjects of this study were aware of the difficulties in oral management as the number of implants increased, so it is thought that they showed high compliance.

On the other hand, in the analysis of smoking and compliance, in the complete compliance group, the proportion of smokers (51.4%) was slightly higher than that of non-smokers (48.6%) (p<0.05). This was different from the results [7,8] in which non-smokers showed a high proportion of fully compliant groups in the patient compliance study for maintenance periodontal treatment. This difference in results is thought to be due to the difference in the study subjects, and this study was aimed at patients who underwent implant procedures. Lee et al. [14] case studied the recurrence of inflammation after treatment for peri-implantitis, the rate of progression of inflammation around implants was 38.5% and 72.7% when the number of implants was less than 4 and more than 4, respectively, and non-smokers and smokers were reported as 53.6% and 87.5%, respectively.

After analyzing the area where the subjects underwent implantation. The area that received the most implant procedures was the maxillary posterior and mandible posterior, followed by the maxillary anterior and mandible anterior. This was similar to the results reported in previous papers [15,16] that the largest number of implants were planted in the order of mandible posterior, maxillary posterior, maxillary anterior, and mandible anterior. In addition, in the compliance classification according to implant location, the complete compliance group showed the highest compliance with maxillary anterior (p<0.05), maxillary posterior (p<0.05), and mandible posterior (p>0.05). In the study of Kim et al. [17], it is reported that the loss rate of mandible anterior was very low, and the remaining teeth of the posterior were the least, and the difference in compliance can be explained by the results of the study that the most areas of implant implantation described above were in the order of posterior and anterior. It is estimated that the order of natural tooth loss in patients had an effect on compliance by making them alert to oral health care.

As a result of analyzing the correlation between the compliance of the preventive management program, the number of implants, smoking status, and oral care period, the subjects showed high compliance in the order of management period (p<0.01) and the number of implant placement (p<0.01), but showed low compliance with smoking (p<0.01). A number of studies [17-19] reported that the period during which most implant failures occurred was within 1 year after implantation. Therefore, in the stable maintenance of implants, patients' high oral care compliance is required as important as the dentist's skilled skills related to implant placement [20]. Therefore, in order to increase compliance with oral care, continuous education and motivation are needed to remind the importance of oral care.

As a limitation of this study, it was selected as a suitable subject for research design, and it is judged that there was a limit to deriving research results because the number of samples was not large. In addition, since data were collected based on medical records for three years, patients' opinions on oral care compliance were not reflected. Nevertheless, this study is a preventive management program operated by a dental clinic, and is meaningful in that it identified local factors that affect compliance of patients undergoing implantation. In the later study, it is necessary to identify related to factors that affect oral management programs, including factors that affect the factors that affect the net adaptation of oral management programs.

This study conducted a three-year retrospective study on 69 patients undergoing oral care centered on PMTC after implantation to confirm the relationship with various local factors (patient's gender and age, smoking status, oral care period, number of implants, and implant placement location) that are expected to affect compliance with the preventive management program.

First, the 3-year persistence rate for the preventive management program for 69 patients was 31.9%, and the cumulative persistence rate was 23.1%. In addition, the proportion of patients who were discontinued during one year was 58.4%, of which 50.7% stopped management within three months. Second, 53.6% of all subjects in age were in their 60s or older, and even in the complete compliance group, it was the highest at 51.4% in the 60s or older group, but the effect on compliance was not statistically significant (p>0.05). Third, 57.1% of the complete compliance group had more than 7 implants, and 51.4% were smokers, and the effect on compliance was statistically significant (p<0.05). Fourth, the complete compliance group at the implantation position showed the highest compliance in the maxillary anterior and maxillary posterior (p<0.05). Finally, the subjects showed high compliance in the order of the management period and the number of implants, but showed low compliance with smoking (p<0.01).

Based on the data presented in this study, if the correlation with local factors affecting the compliance of the preventive management program is identified and applied in clinical practice, it is believed that it can help patients improve their compliance with oral care.

This work was supported by the Gimcheon University Research Grant of 2022.

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