With rapid development of medicine, the number of elderly people, and consequently, elderly patients in dental practice, is constantly increasing. Despite the efforts of dentists to educate patients on oral hygiene (to prevent oral health diseases), and to treat diseases such as dental caries and periodontitis, tooth loss is still a significant problem, both in younger and older people (1-3). Basically, edentulism (partial or total) is very unpleasant because it affects normal functional activities such as speech, ability to eat (selection and enjoyment of food), and esthetic appearance (4). Also, tooth loss psychologically affects people and is closely related to the physical- and mental-related quality of life (5). Loss of all teeth can be experienced as losing vitality and getting older (4, 5). In essence, oral disorders such as tooth loss can affect interpersonal relationships and daily activities and therefore the “well-being” or “quality of life” (6). Therefore, the goal of contemporary dentistry is to improve oral health, thus improving overall quality of patients’ life.
Health is a state of complete physical, mental, and social well-being and not merely the absence of disease and infirmity (7). From this point of view, the ultimate goal in dentistry is not only the absence of dental caries, periodontitis, and/or other oral diseases, but also the mental and social well-being of patients. Oral health has always been considered an important part of patient’s general health due to the fact that oral diseases can interfere with the daily life activities, thus affecting general quality of life (6, 8). Oral Health Impact Profile (OHIP), originally developed in Australia in the English language, is the most commonly used questionnaire to study and evaluate the oral health related quality of life (OHRQoL) (9, 10). As one of the most comprehensive subjective oral health status measures, the OHIP is designed to measure self-reported dysfunction, discomfort, and disability attributed to oral conditions (11, 12). The original OHIP instrument consists of 49 items representing seven domains, but shorter and larger versions have also been developed (9, 10, 12). Longer versions were developed by adding some culture-specific items or specific disease protocols (12). It is also used among patients wearing fixed and removable dental prostheses (13, 14) to evaluate the impact of prosthetic therapy on oral health and general quality of life.
Edentulous maxillary and/or mandibular jaw are conventionally treated with complete removable dental prostheses (CRDP) and the success of such prosthetic therapy is differently evaluated by dentists and their patients (15). Personal satisfaction is often the most important factor in patient’s evaluation of dentures, not their technical quality (excellence). Patient’s satisfaction is individual and multicausal, depending on their prior experience, expectations, health, and condition of the oral cavity as well as on emotional and general health status (15). Many published papers confirmed the connection of oral health and general quality of life (14, 16-19). Many authors reported improvement of patients’ oral health and overall quality of life (patient’s subjective assessment) after prosthetic treatment was performed, or after correction (denture relining) of existing prosthetic modality (16-19). Poor retention and stability of CRDP due to the residual ridge resorption, especially in the mandible, can affect patient’s satisfaction and OHRQoL. According to results reported by Furuyama et al., (17) in patients with implant-supported fixed dentures, the OHRQoL was generally less impaired than it was in patients with partial removable dental prosthesis. Unfortunately, the use of dental implants for retaining CRDP is not a common method for edentulous patients in Croatia because the Croatian Institute for Health Insurance covers the costs of conventional CRDP, but not those of implant-supported CRDP.
Due to the aforementioned influence of edentulism and prosthetic treatment on OHRQoL, the aim of this study was to determine the OHRQoL (using Croatian version of OHIP-49 questionnaire) in a group of elderly people (residents from elderly care homes) wearing CRDP. Since many factors influence OHRQoL, such as the patient’s age, tooth loss, existing pathologies, sociodemographic, cultural, educational, psychological, dietary, and financial factors (18), another aim of this study was to assess the influence of factors such as patient’s age, gender, level of education and profession, residence place size, the “day–night” or just “daily” habit of CRDP wearing, type of CRDP, total time of denture wearing period (period of edentulism), and the age of CRDP on OHRQoL.
Materials and Methods
This cross-sectional study included 301 participants wearing mandibular and/or maxillary CRDP. The participants included in this study were residents of elderly care homes in the area of Zagreb and Slavonski Brod in Croatia. The selection criterion for inclusion of participants in the study was good mental and cognitive health in order for them to be capable to understand and fill out the questionnaire. They were all informed about the objectives and aims of this study after which a written consent was obtained for their participation. The present study was approved by the Ethics Committee of the School of Dental Medicine, University of Zagreb, Croatia.
The questionnaire used in this study consisted of two sections. The first section consisted of questions about age, gender, number of inhabitants – population of residents’ original place/hometown from where participants came to Zagreb or Slavonski Brod (up to 10,000 residents, 10,000–50,000 residents, 50,000–100,000 residents, 100,000–300,000 residents, and more than 300,000 residents), participants’ level of education (no school completed—NS, completed elementary school—ES, completed high school—HS, and college/university degree—CO), participant’s profession, “day–night” or just “day” time denture wearing, and the time of denture wearing period (period of edentulism expressed in years).
The second section of the questionnaire used in this study was the Croatian version of OHIP-49 questionnaire (12). This questionnaire consists of 49 items representing seven domains: functional limitation (9 items), physical pain (9 items), psychological discomfort (5 items), physical disability (9 items), psychological disability (6 items), social disability (5 items), and handicap (6 items) (12). All the participants filled out the Croatian version of the OHIP-49 questionnaire with the help of one of the authors—the examiner; therefore, the response rate was 100%, with all the questions answered. For each question, the participants were asked how frequently they have experienced the investigated variable during the past month. Responses were rated using a Likert-type scale (0=never, 1=hardly ever, 2=occasionally, 3=fairly often, 4=very often). Zero indicated the absence of any problems. The higher scores indicated more impaired oral health (12).
The results obtained were statistically analyzed using computer software SPSS 15.0 (SPSS Inc., Chicago, Illinois, United States) by the method of descriptive statistics, and the differences tested for significance by the independent sample Student’s t-test, χ2 test, one-way ANOVA, and Scheffe post hoc test, with a significance level of 0.05.
The participants were of an average age of 74 ± 12.1 years (from 60 to 99 years). The study group consisted of 202 female (67%) and 99 male (33%) participants. Distribution of the participants according to the age, residence place size, level of education, profession, type of CRDP, and wearing period of removable dental prosthesis (current and previous) is shown in Table 1.
Mean values obtained for each domain of OHIP-49 questionnaire were as follows: functional limitation 6.7; physical pain 5.1; psychological discomfort 2.0; physical disability 5.9; psychological disability 2.4; social disability 1.2; handicap 2.8; and OHIP summary score was 26.5.
According to the age groups, Scheffe post hoc test revealed statistically significant (p<0.05) higher psychological discomfort among participants younger than 65 years (X=3.22) compared to participants aged from 66 to 75 years (X=1.50), as well as statistically significant (p<0.05) higher psychological disability in a group of participants younger than 65 years (X=3.94) compared to participants older than 86 years (X=1.32).
According to the participants’ gender, age of current CRDP, and denture wearing habit (“day–night” or just “daily” CRDP wearing), no statistically significant differences were revealed (p>0.05).
According to the residence place size, statistically significant (p<0.05) higher mean value of OHIP score was yielded for each of 7 OHIP domains and for OHIP summary score among participants coming from places with less than 10,000 residents in comparison to participants from more populated places (Table 2). According to the level of education, Scheffe post hoc test revealed statistically significant (p<0.05) difference between OHIP score mean values for psychological disability between NS participants (X=5.32), CO participants (X=1.51), and ES participants (X=1.70). Taking into account participants’ profession group, Scheffe post hoc test revealed statistically significant (p<0.05) differences in OHIP mean values for psychological disability, social disability, and handicap, with higher OHIP mean value for agriculture group and participants “outside of mentioned groups” (Table 3). According to the type of removable dental prosthesis, Scheffe post hoc test revealed statistically significant (p<0.05) results as follows: higher physical pain for only mandibular CRDP wearers (X=8.41) compared to wearers of both mandibular and maxillary CRDP (X=4.63); higher social disability in only maxillary CRDP wearers (X=2.14) compared to wearers of both mandibular and maxillary CRDP (X=0.88); and bigger handicap in only maxillary CRDP wearers (X=3.79) compared to wearers of both mandibular and maxillary CRDP (X=2.36). With regard to the length of denture wearing period (previous and current removable dental prosthesis, expressed in years), statistically significant differences were revealed in each OHIP domain (Table 4).
p - p value, SE - standard error, *p < 0.05
p - p value, SE - standard error, *p < 0.05
p - p value, SE - standard error, *p < 0.05
In this study, the elderly patients wearing CRDP were chosen as participants to reveal their current OHRQoL, using OHIP-49 questionnaire (12). The original OHIP-49 questionnaire was translated into the Croatian language and adapted to Croatian cultural environment. Therefore, this Croatian version of OHIP-49 questionnaire (12) was very suitable for use in this study. All components of OHRQoL were equally important in formation of subjective assessment of oral health and its impact on quality of life. Generally, in this study, the highest OHIP mean values were observed in domains of functional limitation, physical pain, and physical disability meaning that the most of participants’ difficulties with CRDPs were related to mastication, speech, bad odor, taste and type of food, oral pain (acute or chronic), headache, communication, social interactions, and CRDP cleaning difficulties. Similar results were reported by Baretto et al., (13) with the emphasis on improvement of oral health after new dentures were produced. Baretto et al. also stated that good oral rehabilitation has a positive impact on the physical, social, and psychological well-being of patients (13). Study conducted by Zlataric et al. (21) tried to identify factors influencing variability in general patient satisfaction with their dentures. Authors of that study concluded that esthetics, retention, speech, chewing, and comfort of denture wearing significantly influence patients’ satisfaction with removable dental prostheses and therefore could be important factors for assessing OHRQoL (21). In our study, these factors were also included in OHIP-49 questionnaire domains revealing the highest values.
Kotzer et al. (22) concluded that references on which people base their oral health can range depending on a host of variables. Often, people compare their general health status as well as their oral health condition with health condition of other people with the same age, some use their physical and emotional state to assess oral health, while others who have, or perceive themselves as having poor oral health, may actually be satisfied with the state of their oral health (22). According to the results from this study, the examined factors such as participants’ age, education, profession, residence place size, type of CRDP, and the time of denture wearing period significantly affected OHRQoL. Residence place size, profession, and the time of denture wearing period were factors with the highest impact on OHRQoL, affecting almost all domains from OHIP-49 questionnaire. It is logical to assume that younger participants and those with lower level of education (especially NS and ES participants) have greater expectations (even unrealistic) due to the lack of understanding of functional limitations of CRDP treatment, often comparing the dentures to their natural teeth (23). Smith et al. reported that patients’ expectations of complete dentures may differ between individuals but also between patient groups managed in teaching hospitals and dental practices (24). Significant number of patients from teaching hospitals considered “absence of pain” and “presence of good bite” as essential properties of complete dentures (24). According to the results of this study, a higher impact on OHRQoL was observed among younger participants (less than 65 years), especially in domains of psychological discomfort and disability, and among NS participants just in domain of psychological disability. As patients age, some of them accept that their health is deteriorating so they are more likely to consider minor or even severe oral health problems as insignificant (22). That could be a reason why lower impact on OHRQoL was noticed among older participants. Furthermore, in a study conducted on Canadian population (not exclusively prosthetic patients), Kotzer et al. concluded that people in rural areas have the poorest OHRQoL due to decreased access to dental care opposed to people from urban areas (22). According to our results, it could be stated that participants from smaller (rural) places and also participants with shorter period of denture wearing were more dissatisfied with CRDP with negative impact on OHRQoL. Among the participants with longer denture wearing period (10 years and more), a lower mean value of OHIP score was found. It seems that during a longer denture wearing period, most patients learn to accept functional limitations of dentures and establish a certain satisfaction level (19). Another important problem for edentulous patients is residual ridge resorption, which starts after teeth extraction. If progressive, it often leads to a clinical situation with insufficient bone support for the proper functioning of CRDP (25). This problem is especially expressed in the mandible (25) giving unfavorable shape of residual ridge compromising removable prosthesis’ retention and stability. Its function will become insufficient, thus affecting patient’s satisfaction and OHRQoL. Therefore, overall higher dissatisfaction among mandibular CRDP wearers (compared to the other participants) was expected. Unexpectedly, just a higher physical pain for mandibular CRDP wearers (compared to both maxillary and mandibular CRDP wearers) was revealed. A possible explanation could be in aforementioned fact that patients adjust to gradual changes in denture fit and alterations in supporting bone during the denture wearing period (19). Also, patients’ satisfaction with their dentures is not always correlated to the assessment of dentures by dentists, so this difference should be also considered in this case (5).
The obtained results among CRDP wearers revealed significant influence of general and sociodemographic factors on subjective participants’ perception of oral health and OHRQoL. Factors such as participant’s age, education, profession, residence place size, type of CRDP, and the length of denture wearing period significantly correlates with OHRQoL. Factors such as participant’s age, smaller residence place size, lower level of education, and shorter period of denture wearing had higher impact on OHRQoL among CRDP wearers.