Change in Patients ’ Self-Reported Quality of Life before and after Dental Implantation

Background/Aim: The loss of teeth and its consequences for health, as well as the psychological discomfort it entails, have a negative impact on both self-reported health state and quality of life (QoL). Dental implantation aims to increase patients’ health and satisfaction and to improve all aspects of QoL. The purpose of this cross-sectional correlational study was to compare the patients’ QoL before and after dental implantation. Material and Methods: The study comprised 62 patients aged between 24 and 77, including 28 (45.16%) women and 34 (54.84%) men, who reported to a private dental clinic in Szczecin, Poland to replace missing teeth with implants. The survey was carried out twice: prior to the treatment, when the decision to use implants had been made, and three months after implantation, during the first check-up. QoL was measured using the 36-Item Short Form Health Survey (SF-36), and sociodemographic data were collected using a questionnaire of the author. Results: There were statistically significant differences between the assessment of health and QoL before and after implantation treatment. Both the patients’ health and comfort of life improved after therapy. Conclusions: Replacement of missing teeth with dental implants brought overall improvement in patients’ QoL, social comfort, and general health. Dental implantation should be recommended in the early phase of edentulism, after tooth loss.


Introduction
The loss of teeth is a serious life event that impairs two important functions, eating and speaking, and may be accompanied by problems such as pain and bleeding associated with gum disease.It thus affects various aspects of Quality of Life (QoL).Patients experience pain and psychological discomfort [1][2] .Somatic diseases may cause pathological changes within the oral cavity, potentially leading to partial or complete edentulism and, consequently, to the need to replace the missing teeth with implants 1,[3][4][5] .
QoL and general health can serve as important indicators of the effects of a treatment, and should be taken into account during oral diagnosis, interventions, and the application of procedures [5][6][7] .Recent studies have revealed significant relationships between QoL, overall oral status, orthodontic treatment, and treatment with prosthetic implants 3,8 .
QoL is defined as an individual's perception of his or her position in life, within the cultural context and value system he or she lives in, and in relation to his or her goals, expectations, parameters, and social relations 6,9 .QoL is regarded as a dynamic construct that changes over time, and which can be affected by health problems that occur 5 .As a vital outcome of therapy, QoL is rated among the so-called soft effects of treatment, since it modifies the internal and external conditions affecting the individual.
Researchers examining the effect of edentulism on the oral health-related quality of life (OHRQoL) have demonstrated that patients suffering from this problem had lower levels of QoL, higher levels of functional dental implantation (this usually took place three months after the treatment).
The criteria for inclusion in the study were age at least 18 years, committed to dental implantation, agreement to take part in both surveys, successfully completed implantation treatment, and attending the check-up.Each patient was examined by a dentist using a mirror and a probe under artificial lighting.The dentist assessed the patients' needs for treatment and the oral health status.

Procedure
Our study was approved by the Bioethics Committee of the Pomeranian Medical University in Szczecin, Poland (approval no.KB-0012/41/05/15).The patients participated in the study voluntarily and gave their informed consent.The study was conducted in accordance with the guidelines of the Helsinki Declaration and the principles of Good Clinical Practice, as well as with respect for the rights and dignity of the person.

Evaluation of oral health-related quality of life (OHRQoL)
The research instruments used in this survey-based study were the 36-Item Short Form Health Survey (SF-36) and a questionnaire of the author's devising (AQ).We obtained permission from Quality Metric, Inc. to use the authorized Polish Version of the SF-36.The SF-36 questionnaire consists of 36 questions divided into eight subscales: role physical (RP), mental health (MH),bodily pain (BP), general health (GH), physical functioning (PF),vitality (V), social functioning (SF), role emotional (RE), and one additional question concerning health change 18,19 .Score on the Likert scale for each of these areas ranges from 0 to 100, with 0 denoting the worst and 100 the best possible health state.SF-36 is not timeconsuming to use, and its usefulness, repeatability, and ability to reveal changes in QoL have been demonstrated 20 .The author's questionnaire contained 20 simple structured questions aimed at (1) demographic data collection (age, sex, place of residence, education, marital status, financial income), (2) selected clinical data concerning implantation treatment.

Statistical Analysis
The normality of variables distribution was verified using the Shapiro-Wilk test.The variables were characterized by arithmetic means (X), standard deviations (SD), medians (M), and extremes (min-max).Statistical analysis was performed using the chi-square test, Student's t-test, analysis of variance (ANOVA), the correlation coefficient, and Cronbach's alpha, in order to assess the reliability of the results in particular SF-36 domains.All tests were performed at a statistical significance level of α = 0.05.limitation, more severe physical and psychological pain, and more serious sleep and digestive disorders [10][11][12] .The purpose of prosthetic treatment is to alleviate tooth lossrelated functional and esthetic problems, and to improve QoL.According to Levi, one factor that motivates people to choose a particular method of tooth replacement is the esthetic aspect 13 .Patients who decide to undergo dental implantation feel a difference in their own perception of themselves 14 .Dental implants are made of titanium and are inserted directly into the jawbone.On account of the osseointegration and mechanical stability they offer, they serve as pillars for prosthetic filling.Bone grows up to the implant surface, meaning that the implant can function as a natural tooth.Providing that hygiene principles are obeyed, implants should continue to function properly.Implantation treatment aims to reconstruct missing teeth, thus restoring the normal functioning of the stomatognathic system, providing lips with support and, consequently, restoring facial profile and improving appearance.Implant-based definitive dental prostheses are widely applied as a highly efficient prosthetic treatment method 11,15 .Some researchers maintain that the QoL related to edentulism, as well as its health, functional, psychological, and social consequences, the therapy employed, and oral hygiene during implantation treatment has not yet been fully described 10, [16][17] .An important contributor to QoL is the overall health and oral hygiene status.QoL assessment is widely used in dental medicine, since it provides information about changes in patients' self-perceived health and QoL level in the course of the pathological process and after dental treatment.Nevertheless, as Riordain et al. ave pointed out, there is still too little evidence for improvement in QoL after implantation treatment 4 .
The aim of this study was to compare the QoL of patients subjected to dental implant treatment before and after the treatment.We assumed that this method of replacing missing teeth has an effect on QoL and the selfreported health state.

Study Design
This was a longitudinal clinical study with selected predictor variables.We formulated the hypothesis that, the patients' QoL would be considerably improved following implantation.The survey was carried out twice during 2015 using the same questionnaire: once at the initial visit (V1), during which the doctors and patients established the protocol of dental implant treatment (including treatment date), and then on the first check-up (V2), after (16 -57.14%), and the men as good or average (22 -64.7%), 2. There was a statistically significant relationship between health assessment three months before treatment (X= 6.78 ± 1.85) and three months after treatment (X= 8.64 ± 1.50) (Table 2), 3. Health assessment statistically significantly depended on economic status (p= 0.04); the higher patient's economic status, the better health assessment, 4. Patients observed positive changes in their comfort of life, which were reflected in higher health assessment (p= 0.05).

Quality of life
1.The highest score was obtained for the physical functioning (PF) (X= 89.68 ± 14.43), and the lowest for the general health (GH) (63.87 ± 18.34) and vitality (V) (73.63 ± 16.17) domains.Cronbach's alpha was calculated for each of the SF-36 scales.
For the physical functioning (PF), mental health (MH), vitality (V), bodily pain (BP), and general health (GH) domains, alpha was > 0.7, which suggested high reliability of the scales; for the role physical (RP) and role emotional (RE) domains, alpha was < 0.7, 2. The women scored higher for physical functioning (PF) than the men (p= 0.03), and the younger patients (aged up to 60 years) scored higher than those over 60 (p= 0.01), 3. The correlation coefficient for the physical functioning (PF) and role physical (RP) domains was 0.718 (p< 0.001), while for the mental health (MH) and vitality (V) domains, this was 0.756 (p< 0.001), 4. The lowest scores for general health (GH) were obtained by the patients aged between 56 and 60 years, while the highest was obtained by those younger than 55 (p= 0.005).The lowest scores were obtained by patients with vocational and secondary education only, and the highest by those with thirdlevel education (p< 0.001), 5.The largest changes in health status were reported by patients over 60, and the smallest by patients aged up to 55 years (p= 0.05), 6.Higher economic status was associated with an increase in the average score for the vitality (V) QoL domain (p= 0.03),

Health assessment before and three months after implantation treatment (on the check-up):
1.The participants described their health as excellent (3 -4.84%) or very good (25 -40.32%),The mean score was 8.77 ± 4.29.The women more often described their health state as excellent or very good Unauthentifiziert | Heruntergeladen 14.09.19 20:09 UTC implementation, patients found their QoL to be noticeably higher, whereas the QoL of patients with dentures was definitely lower 16 .Similar results, confirming the alleviation of physical pain and psychological discomfort, have been reported by Yoshida et al. 17 .We observed a statistically significant relationship between the patients' health assessment before the treatment and three months after it.We found that the assessment of patients' health changed significantly, after implantation it was significantly higher by 2 units on average.In his study, Yoshida measured chronological change in the QoL level during implantation treatment in a group of 20 patients with a small number of missing teeth (less than 4 teeth), who underwent implantation treatment 17 .The patients completed the shortened Japanese version of the Oral Health Impact Profile (OHIP-J14) before surgery (T0), one week after surgery (T1), one week after interim prosthesis placement (T2), and 1 week after definitive prosthesis placement (T3).Although a temporary functional limitation was observed after implant placement, overall OHRQoL improved after placement of the definitive prosthesis.What is more, implantation treatment was more effective in the unilateral free-end edentulous space.Similarly, in the study of Pavel et al., the most significant associations on the functional scale (FS) were observed with the number of front teeth replaced with implants, followed by the presence of chewing problems and marital status 25 .

Conclusions
This study has demonstrated the significant effect of implantation, as a method of treating missing teeth, on the self-reported health state.Implantation treatment improved patients' health, QoL, and comfort of life.QoL as measured by the SF-36 was higher after the implantation treatment than before it.Dental implantation should be recommended in the early phase of edentulism, after tooth loss.

Table 1 .
Sociodemographic data of the participants (n=62)