|Year : 2020 | Volume
| Issue : 7 | Page : 5-12
Negative impacts of self-reported five-year incident tooth loss and number of teeth on oral health-related quality of life
Supawadee Naorungroj1, Songchai Thitasomakul2
1 Department of Conservative Dentistry; Common Oral Diseases and Oral Epidemiology Research Center; Prosthodontics and Occlusion Rehabilitation Research Unit, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Thailand
2 Department of Preventive Dentistry; Children Oral Health Promotion and Prevention Research Unit, Faculty of Dentistry, Prince of Songkla University, Hat Yai, Thailand
|Date of Web Publication||17-Jan-2020|
Dr. Supawadee Naorungroj
Department of Conservative Dentistry, Faculty of Dentistry, Prince of Songkla University, 15 Kanjanavanich Road, Hat Yai, Songkhla 90112.
Source of Support: None, Conflict of Interest: None
Aims and Objectives: This cross-sectional study aimed to determine the impacts of five-year incident tooth loss on oral health-related quality of life (OHRQoL) in Southern Thai adults and the differences in OHRQoL regarding the number of teeth. Materials and Methods: The study samples included 657 dentate men and women, aged 35–65 years. The Thai version of the Oral Impacts on Daily Performances (OIDP) index was used to assess oral impacts. The number of teeth was grouped as 1–19 versus ≥20 teeth. Self-reported five-year incident tooth loss was classified as none, 1–2 teeth, or ≥3 teeth. Odd ratio (OR) and 95% confident interval (CI) were presented. All analyses were carried out using STATA software, version 13.1. Results: Approximately 22% of participants had fewer than 20 teeth. More than half (54%) of the participants had lost ≥ 1 tooth. OIDP were experienced by approximately 54% of participants, where impacts on eating were frequently reported. Adjusted multinomial logistic regression analyses showed that ≥3 lost teeth and having 1–19 retained teeth was significantly associated with the greater prevalence of oral impacts (OR = 9.80; 95% CI = 2.96–32.51). Conclusion: Tooth loss and its impacts affecting daily life were common among these study samples. The largest effect on impaired OHRQoL was presented by those with fewer teeth and a greater number of incident tooth loss during the past five years.
Keywords: Number of Teeth, Oral Health, Oral Health Impact, Quality of Life, Tooth Loss
|How to cite this article:|
Naorungroj S, Thitasomakul S. Negative impacts of self-reported five-year incident tooth loss and number of teeth on oral health-related quality of life. J Int Oral Health 2020;12, Suppl S1:5-12
|How to cite this URL:|
Naorungroj S, Thitasomakul S. Negative impacts of self-reported five-year incident tooth loss and number of teeth on oral health-related quality of life. J Int Oral Health [serial online] 2020 [cited 2020 Oct 23];12, Suppl S1:5-12. Available from: https://www.jioh.org/text.asp?2020/12/7/5/276084
| Introduction|| |
The oral health-related quality of life (OHRQoL) measure, a subjective evaluation of people’s perceptions about oral health and its impact on their lives, is used to identify needs, monitor disease progression, and evaluate public health or health-care service programs. As a subjective measure, quality of life is a dynamic construct that changes over time., Assessing OHRQoL has become a major focus in oral health research and many countries have incorporated this subjective oral health status measure into national surveys.,,, Epidemiological studies in a variety of diverse populations have shown the link between OHRQoL and oral health conditions, socioeconomic backgrounds, and lifestyle factors.,,,, Among clinical measures, tooth loss is a strong and consistent predictor for OHRQoL assessment across the diversity of population and the variety of OHRQoL instruments., However, the majority of previous studies was conducted with the Western populations.,, Therefore, the relationship between clinical dental indicators and OHRQoL measures may differ in other groups.
Tooth loss is a risk indicator for chronic systemic conditions, for example, diabetes, stroke, cardiovascular disease, and all-cause mortality., Furthermore, the negative impacts on daily life performance are particularly significant among adults with extensive tooth loss, including those with prostheses.,, Reduced dentition can affect chewing performance, communication, and social interaction.,, Although tooth loss and edentulism prevalence in Thailand is declining, there are still substantial disparities across the country.,,, The southern areas tend to have a higher prevalence of edentulism and a lower proportion of older adults aged 60–74 years who have retained ≥20 teeth compared to other Thai regions. However, less is known concerning dental status and perception regarding the importance of preserving natural teeth and their impacts among this group.
In addition to oral health problems, several health behaviors and sociodemographic factors have been associated with OHRQoL. Objective measures of dental diseases, that is, the presence or absence of dental caries, periodontal pockets, and tooth loss, provide information about the end point of the disease process. However, its impact on function or psychosocial well-being is not clearly known. When attempting to launch oral health and disease prevention programs, OHRQoL assessment provides useful information for resource allocation and increasing the understanding of how individuals perceive oral health needs and what oral health outcomes drive them to access dental care.
The objective of this study, therefore, was to examine the prevalence of self-reported tooth loss during the past five years and the number of retained teeth as well as their impacts on quality of life in a group of Thai adults. Furthermore, we investigated whether there was a difference in the association between the extent of self-reported tooth loss (none, 1–2 teeth, or ≥3 teeth) and OHRQoL regarding the number of retained teeth (1–19 teeth vs. ≥20 teeth).
| Materials and Methods|| |
Study design and study participants: This cross-sectional analysis of baseline data of a longitudinal study of tooth loss incidence and risk factors was approved by the Institutional Review Board of the Faculty of Dentistry, Prince of Songkla University (EC5801-01-L-LR). Baseline data were collected between September 2015 and April 2017. Subjects were purposively selected from four communities to represent people from the lower regions of Southern Thailand: (1) La-Ngu District, Satun Province, (2) Na-yong District, Trang Province, (3) Papayom, Patthalung Province, and (4) Klong-Hoi-Khong District, Songkla Province. Approximately 200–250 subjects from each area were contacted by health volunteers. They were informed about the study and told that their participation was voluntary. A total of 943 subjects, aged between 35 and 65 years, consented to this study. For the purpose of this study, 657 subjects with complete data and reported history of dental service utilization within the past five years were included in the analysis.
Data collection: Data collection consisted of interviews and clinical examinations. The face-to-face interviews were conducted by trained interviewers. The interviewers collected data on sociodemographic variables (e.g., age, religion, and years of educational attainment), oral behaviors (e.g., toothbrushing, consumption of soft drinks and sweets, and dental service utilization), medical history (e.g., hypertension or diabetes), health behaviors (e.g., smoking and alcohol consumption), and self-reported five-year incident tooth loss.
OHRQoL data were assessed using the Oral Impacts on Daily Performances (OIDP) questionnaire. The OIDP indicator is a composite measure of OHRQoL, which measures oral conditions that seriously affect eight aspects of an individual’s daily life, including eating and enjoying food, speaking and pronouncing clearly, cleaning teeth, sleeping and relaxing, smiling and showing teeth without embarrassment, maintaining usual emotional state, enjoying contact with people, and carrying out major work. A Thai version of the OIDP instrument has been validated and carried out with Thai adult population.,, Data were collected on the frequency and severity of such impacts. Participants reported the frequency and severity of each oral impact on a scale from 0 to 5 (very little to very severe). OIDP scores for each reported oral impact were calculated by multiplying the frequency and severity scores to obtain performance scores. Then, the total score was expressed as the sum of those performance scores. The binary variable of OIDP was derived as “no impact (performance score = 0)” versus “at least one impact (performance score >0).”
Participants received clinical oral examinations from one examiner. The assessment of the number of teeth present, excluding retained root, was determined by a tooth count during the study examination and then grouped as 1–19 teeth vs. ≥20 teeth. The presence of coronal and root caries, coronal and root fillings, and root fragments was recorded, and recoded as “yes” versus “no.” A periodontal examination of the participants was conducted by modifying the Community Periodontal Index (CPI). Periodontal probing was assessed at four sites (mesiodistal, mesiobuccal, distobuccal, and distolingual) for all teeth, except third molars. The highest value among CPI scores from the examined sites of each tooth was used as the tooth’s representative CPI scores. The presence of CPI score = 4 (probing depth ≥ 6 mm) was recorded as “yes” versus “no”.
Statistical analysis: Descriptive statistics were computed to assess the frequency of nominal and categorical data (e.g., gender, years of education, and health history). Prevalence of participants who reported at least one impact on daily performance was presented. Bivariate analyses were made using the chi-squared test for the associations of sociodemographic characteristics, health status, health and oral health behaviors, and oral health status with self-reported five-year incident tooth loss. Bivariate correlations of self-reported five-year incident tooth loss and oral impacts were also assessed using the chi-squared test. The associations of self-reported five-year incident tooth loss and oral impacts were investigated through binary logistic regression. The main outcome of interest was the presence of oral impacts on quality of life. Independent variables included the extent of five-year incident tooth loss categorized as 1–2 teeth versus none and >3 teeth versus none. The analyses were carried out separately for people with 1–19 teeth and ≥20 teeth. A hierarchical model adjustment for potential confounders (sociodemographic variables, smoking, toothbrushing, and clinical variables) was carried out. Potential confounders were selected based on variables significantly associated with the independent variable or the outcome of interest. Odd ratio (OR) and 95% confident interval (CI) were presented. All analyses were carried out using STATA version, 13.1 (StataCorp, College Station, Texas).
| Results|| |
The final analytical samples consisted of 657 participants, with men and Buddhist comprising 24.8% and 73.5% of the analyzed sample, respectively. Approximately half (51.8%) of the study samples had education levels of six years or less. Most of the participants (81.5%) were under universal health-care coverage. More than half (n = 355, 54.0%) of the study participants had lost at least one tooth during the past five years. Self-reported tooth loss experience was significantly associated with all reported baseline social determinants at a significance level of 0.05. A greater number of lost teeth (≥3 teeth) were more commonly reported among participants who were male (28.6%), older (21.5%), Muslim (23%), of lower educational attainment (23.8%), and under universal health care (19.7%) [Table 1].
|Table 1: Associations of participants’ characteristics with self-reported five-year incident tooth loss (n = 657)|
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The prevalence of self-reported hypertension and diabetes was 15.8% and 10.2%, respectively. However, no statistically significant association of hypertension and diabetes prevalence with the self-reported incident tooth loss was observed. With respect to oral and health behaviors, smoking (P < 0.001) and toothbrushing (P = 0.011) habits were significantly associated with self-reported five-year incident tooth loss. Approximately 71% of former or current smokers compared to approximately 51% of nonsmokers had lost at least one tooth. Most of the study participants (94.2%) reported toothbrushing twice a day or more. Of those who reported infrequent toothbrushing (5.8%), 71% reported ≥ one lost tooth, which was higher than those who brushed their teeth regularly (55.7% for those brushing teeth twice a day and 43.5% for those brushing their teeth more than twice a day) [Table 1].
Associations of the clinical variables with self-reported five-year incident tooth loss are given in [Table 2]. Approximately 22% of study participants had fewer than 20 remaining teeth. Approximately 60% and 21% experienced coronal and root caries with mean numbers of 1.45 ± 1.75 and 0.38 ± 0.92, respectively (data not shown in the table). The figure for study participants with deep pockets was 26.8%. Incident tooth loss was significantly associated with all clinical measures except for root caries. Compared to participants who maintained ≥20 teeth, those with fewer teeth (1–19 teeth) at baseline examination also reported greater tooth loss incidence during the past five years (48.5% vs. 73.3%). The presence of root fragments (P < 0.001), coronal caries (P = 0.002), and probing depth ≥ 6 mm (P < 0.001) were positively associated with incident tooth loss. In contrast, coronal filling and root filling were negatively associated with incident tooth loss (P < 0.001).
|Table 2: Associations of oral health status with self-reported five-year incident tooth loss (n = 657)|
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According to [Table 3], the prevalence of OIDP frequency scores in this study group was 53.9%. Overall, subscale OIDP frequency scores ranged from 1.8% (carrying out work adequately) to 45.7% (eating and enjoying food). Significant differences of subscale OIDP frequency with respect to incident tooth loss were observed for eating and enjoying food, speaking and pronouncing clearly, and smiling, laughing, and showing teeth without embarrassment (P < 0.001). Approximately 71% who had tooth loss ≥ three reported an impact on daily performance when eating and enjoying food compared to 43% and 38% of participants with 1–2 lost teeth and no lost teeth. For participants with tooth loss ≥ three, the second greatest oral impacts on daily performance were difficulties with speaking and pronouncing (19.2%), and smiling, laughing, and showing teeth without embarrassment (18.3%).
|Table 3: Prevalence of oral impacts daily performance and subscale and the associations with self-reported five-year incident tooth loss (n = 657)|
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In the assessment, the impact of oral health status on the quality of life, the lower number of teeth, the presence of root fragments, coronal caries, and deep pocket depth were positively associated with OIDP. In contrast, the presence of coronal filling was inversely associated with OIDP. No significant difference was observed in quality of life impacts regarding the presence of root caries or root fillings (data not shown in table). According to [Table 4], the number of retained teeth-specific unadjusted and adjusted multinomial logic regression analyses revealed that without regard to the number of retained teeth, an increased OR tended to be observed among the participants with a greater extent of tooth loss compared to those with no tooth loss experience during the past five years. However, a significant difference in quality of life was observed only among participants who retained 1–19 teeth and had lost ≥3 teeth. The corresponding OR in the unadjusted model was 6.43 (95% CI = 2.50–16.53). After adjusting for sociodemographic variables, smoking, toothbrushing, and selected clinical measures, the OR was increased. The corresponding OR in the final models was 9.80 (95% CI = 2.96–32.51).
|Table 4: Multivariable logistic regression models for effects of self-reported five-year incident tooth loss on overall all oral impacts daily performances by number of remaining teeth (n = 657)|
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| Discussion|| |
This is the first study conducted in Southern Thailand showing the negative impacts of incident tooth loss and the number of retained teeth among adults who reported the use of dental services in the past five years. This study found that individuals who had continuously lost their natural teeth in later life and had few remaining teeth (1–19 teeth) experienced the highest dental impact on daily activities. Furthermore, socioeconomic and behavioral inequalities in tooth loss and OHRQoL were observed in this group. Tooth loss most frequently affected eating performance, highlighting the importance of maintaining oral function over a lifetime.
Oral problems, specifically tooth loss, root fragments, caries, and periodontitis, are highly prevalent chronic conditions in these study samples. This result is similar to previous studies where OHRQoL differs among individuals with various dental conditions.,,,, In this study, all clinical variables have significant impacts on the quality of life to varying degrees except for the presence of root caries and root fillings. Extensive tooth loss ≥3 teeth, 1–19 teeth, and root fragments were the conditions that strongly impaired quality of life compared to other oral conditions. It has been explained that periodontal disease and caries in early stages often did not cause symptoms; thus, the two common oral diseases were not strongly associated with impaired OHRQoL., Only severe dental caries or periodontal disease resulting in pain or discomfort had significant impacts on OHRQoL. It has been shown in several studies that the number of missing teeth at baseline was associated with subsequent tooth loss. In this study, participants who reported a greater number of lost teeth during the past five years were those who now had worse oral conditions (e.g., fewer teeth, severe periodontal disease, and untreated dental caries). As a result, they were extremely high-risk individuals for a greater burden of oral diseases and subsequent tooth loss in the future. Given the negative impacts of tooth loss on OHRQoL, effective oral disease prevention and promotion programs are required to preserve teeth. Furthermore, the use of the OHRQoL as part of a screening instrument to determine a patient’s expectations before starting treatment is important for a successful treatment outcome. Previous studies have shown improved quality of life and patient satisfaction after the provision of dentures and prosthetic rehabilitation, especially implant-supported dentures.,,
Research to date, including a systematic review and meta-analysis, has shown that tooth loss influences quality of life mainly the physical and psychosocial dimensions., With the limitations of different definition of the exposure (tooth loss), several instruments used to measure quality of life, and study setting, our findings are in line with previous studies that tooth loss is associated with OHRQoL.,,,, However, the overall prevalence of oral impacts (53.9%) in this study samples was higher than in previous studies conducted among older (36.5%–52.8%), and middle-aged Thai people (10.0%–22.5%)., Our study also emphasized that participants who recently lost many teeth had the greatest prevalence of oral impacts (73.3%). Furthermore, the severity of the impaired OHRQoL was associated not only with the number of missing teeth but also with the location and distribution of tooth loss independent of OHRQoL instruments used and study populations. In this study, oral impacts relating to eating, speaking, and smiling were prevalent among participants who had lost several teeth in the past five years. Although we did not analyze the distribution and location of tooth loss in this study, it can be anticipated that missing posterior teeth would be associated with specific impaired daily activities such as eating, and missing anterior teeth would be associated with speaking and smiling. However, denture wearing, which has been reported to improve OHRQoL among the Thai elderly, was not taken into account in this analysis. Therefore, the associations of incident tooth loss and number of teeth with OIDP may be overestimated. Apart from tooth loss, further studies should assess condition of the remaining teeth, denture status, and their impacts on OHRQoL.
Apparently, tooth loss is a complex measure of oral diseases. Extensive studies, including this study, have reported significant associations between tooth loss and sociodemographic factors.,,,, Furthermore, incident tooth loss was higher among the participants with no regular use of oral hygiene measures compared to that among the patients with regular use of oral hygiene measures. The reason for tooth loss also differed among age groups and populations. Previous tooth loss may also be complicated by a participant’s or dentist’s preference for tooth extraction as a treatment of choice. In most cases, permanent tooth loss was a consequence of untreated oral diseases, mainly caries and periodontitis., Low socioeconomic status and increased systemic inflammation were associated with the progression of periodontitis and tooth loss. The incidence of tooth loss increased with age, which is a result that agrees with previous studies. The age-specific increase in the tooth loss incidence was due to the cumulative effect of untreated diseases (tooth-related factors) over time.,, To improve inequality in access to dental service and the oral health of the Thai people, basic dental treatments, for example, extraction, filling, and removable dentures are covered by health insurance in Thailand; however, a large proportion of subjects in this study opted to undergo tooth extraction. This may be because they accessed dental health-care services when oral diseases had reached advanced clinical stages where tooth condition was poor, resulting in pain or discomfort, or where more complicated and costly treatments were required. Older subjects in our study tended to experience greater tooth loss than younger adults. A 12-year longitudinal cohort study in South Korea reported that the incidence of tooth extraction was greater among individuals with high household incomes, no disability, and residing in urban areas. In that study, older patients experienced fewer tooth extractions due to reduced access to dental care.
As OHRQoL is a subjective measure, people with chronic disease may perceive their quality of life as better than that of healthy individuals. Paradoxical reports have been previously discussed where (1) older people with tooth loss rated their quality of life better than younger people did or (2) patients who received nonsupported completed dentures in both jaws felt they had a better quality of life than those with at least one overdenture. Individuals who have spent a longer time edentulous have had more time to adapt to their oral conditions. It was evident in this study that comparing subjects with 1–19 teeth and ≥20 teeth, only those with 1–19 teeth resulting from recently losing many teeth in the past five years had a significantly impaired quality of life. Perception of oral health status and how it influences daily life activities, probably context dependent, are therefore important for planning services designed to improve the quality of life.
We do acknowledge that our study has some limitations. A convenient sampling methodology was applied to select the study participants. Moreover, the analysis was restricted to individuals who used dental services in the past five years. Compared to the same age group, the proportion of samples with remaining teeth ≥20 teeth was slightly less (approximately 5%) than that assessed from the general population. Therefore, our results cannot be generalized to other groups. Tooth loss is a simple measure of dental status; however, our study relies on self-reported incident tooth loss with limitation of validity. Lastly, due to a cross-sectional nature of this study, quality of life measure is associated with past exposures or cumulative effects of dental diseases. Thus, it is unable to estimate the causality effect of tooth loss events in later life and the number of retained teeth on quality of life impairment. Further studies using a longitudinal approach is a better study design to improve the strength of findings.
In addition, although the number of teeth is important for OHRQoL, future research should incorporate aspects such as chewing ability and the number of functional units as well as investigate the variation in quality of life impairment with respect to dental care utilization, adjustment for existing dental caries and periodontal disease status.
In conclusion, oral health problems, especially tooth loss, were prevalent in this study group and associated with deteriorations in OHRQoL. A history of recent tooth loss and having fewer teeth has high impacts on daily activities, especially concerning physical performance.
Patient declaration of consent
All study participants provided informed written consent for participation in the study and publication of the data for research and educational purposes.
We are grateful for the support of dental staff from the La-Ngu, Na-yong, Papayom, Klong Hoi-Khong public hospitals, and health-promoting hospital centers for subject recruitment. We greatly appreciate the support and data collection work of Dr. Wilailak Nurit, Dr. Pimwipa Setthaworaphan, Dr. Siriwan Apilapanon, and Dr. Worawit Sakulthai. Lastly, we are very thankful for the participation and important contributions of the study subjects.
Financial support and sponsorship
Data collection and the analysis of this project were supported by the Thailand Research Fund (grant TRF 5880169).
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]