Exploring Patient Knowledge, Attitudes & Practices (KAP) and Utilization Patterns of Prosthetic Dental Services: Insights from the FNU Dental Teaching Clinic in Suva, Fiji Islands

Introduction: Tooth loss significantly impairs oral functions and reduces masticatory efficiency. Prosthodontic rehabilitation maintains the aesthetics, functional support, and masticatory function of the oral cavity. The study aims to assess the knowledge, attitude(s), and practice(s) (KAP) towards prosthodontic rehabilitation and utilization of prosthodontic services among patients visiting the Tuisuva Dental Teaching Clinic (TDTC) between the months of February to April 2022 at the School of Dentistry and Oral Health (SDOH), Fiji National University (FNU) in Suva, Fiji Islands.

Methods: A cross-sectional, self-designed questionnaire-based interview was conducted at TDTC among 83 patients visiting the clinic for teeth replacement using removable complete and partial dentures using a simple random sampling method. A questionnaire containing a total of 32 questions, of which 5 are demographic details, 11 knowledge-based, 8 attitude-based, and 8 practice-based questions, was developed to collect data. Participant responses were entered in Microsoft Excel and analyzed using Epi Info 7.2 Software.

Results: This study showed that participants' knowledge was inadequate and lacked in prime areas of oral health information, whereby 43.37% knew about removable partial dentures (RPDs), 34.94% knew about removable complete dentures while 13.25% did not know about both. The participants demonstrated a positive attitude towards treatment, whereby 72.29% were satisfied, while 16.87% weren’t satisfied with their prosthesis. On the other hand, practice was shown to be insufficient, whereby participants stated that 65.06%wore their prosthesis, while 34.94% stated that they did not.

Conclusion: The findings demonstrated that knowledge might vary among participants based on demographic factors like income, education, gender, and age. Attitude varied from availability and socio-economic status; practice had factors such as cleanliness, duration of appliance, and hygiene practices. The study showed under-utilization of prosthodontic services resulting in patients not demonstrating the need to replace missing teeth in the oral cavity.

The American Dental Association (ADA) defines "prosthodontics," as the branch of dentistry concerned with the diagnosis, treatment, planning, rehabilitation, and upkeep of patients' oral function, comfort, appearance, and health when those patients have clinical conditions linked to missing or inadequate teeth or oral and maxillofacial tissues. The oral prostheses replacing teeth may be removable complete dentures or partial dentures or permanently fixed tooth prostheses, connected to remaining teeth or implanted in the alveolar bone [1]. Prosthodontics also provides oral prostheses to correct deformities, such as cleft palate, and to replace alveolar bone to provide underlying support for dentures [1]. Prosthetic treatment varies widely from replacement of missing teeth in a healthy incomplete dentition to complete rehabilitation of badly damaged teeth to functional form. Edentulous individuals are also at greater risk for different systemic diseases and an increase in mortality rate [2]. Multiple prosthetic options are available for the patient to restore lost teeth, including removable or fixed partial dentures, complete dentures, implant-supported processes and over-dentures [3]. Although complete dentures cannot be considered a substitute for natural dentition, they remain to be a staple treatment option for edentulous patients [2]. The percentage of edentulism has dropped in most Western countries over the past 20 years in each age group as more individuals are living longer with their natural teeth [4]. On the other hand, in less developed nations, where sore teeth are frequently pulled rather than treated conservatively, the rate of edentulism is still rising [3]. There is a case to be made that edentulism rates in emerging nations are unnaturally low because of shorter life expectancies and a correspondingly lower proportion of the elderly and extremely elderly [4]. In a study by Brown D. W. the percentage of edentulism among people 65 and older ranged from 1.3% to 78.0% among the 42 countries cited globally [5].

The cost of prosthodontic treatment depends on the type of treatment requested [6]. Therefore, understanding the patient's knowledge and attitude regarding prosthetic replacement prior to receiving therapy is essential, given the emphasis on patient-mediated concerns in prosthetic treatment planning [1,7]. This could be a useful technique for forecasting whether or not a new prosthesis will be satisfactory [8]. Moreover, due to financial constraints, many Fijians may opt to live with edentulousness rather than treat it. University teaching clinics such as the Tuisuva Dental Teaching Clinic (TDTC) in the School of Dentistry and Oral Health (SDOH) at the Fiji National University (FNU) and other primary dental health centres at the Ministry of Health and Medical Services (MoHMS) provide such services at a low cost. The changing perceptions associated with advancing age, such as the feeling of being too old to adapt to removable dentures and a lack of interest in aesthetics, can be a contributing factor to the unwillingness to restore lost teeth at an advanced age [9]. There has been no previous study conducted in Fiji that assessed the knowledge, attitude(s), and practice(s) (KAP) towards prosthodontic rehabilitation and utilization of prosthodontic services among its patients. In Fiji, financial issues and lack of knowledge among patients may lead to an ignorant attitude towards edentulism and its consequences. Another possible reason contributing to the non-uptake of prosthodontic services may be the absence of dental insurance in Fiji. However, there is a paucity of published data on the prevalence of edentulism and associated factors in the Fijian population, which gave an opportunity to conduct further research in this area, which plays a vital role in the lives of the edentulous people in receiving appropriate prosthodontic treatment.

Study design and sample

This was a qualitative cross-sectional study with a focus on assessing the KAP towards prosthodontics rehabilitation and the utilization of prosthodontic services among patients receiving and who have received removable prosthodontic denture treatment at SDOH Clinic. Demographic factors such as age, sex, educational status, and ethnicity affecting edentulism were assessed in patients receiving prosthodontic treatment services in Suva at the TDTC at SDOH, FNU. All patients that presented to the FNU TDTC and were seen by Bachelor of Dental Surgery (BDS) students in years 3, 4 and 5 for prosthodontic treatment from February to June 2022 as shown in Table 1 with the inclusion criteria for this study are the patients receiving removable prosthodontic treatment, removable prosthodontic appliance or fixed prosthodontic treatment, who are partially edentulous or completely edentulous, both male and female patients, ranging from 18-80+ in age and, patients with a history of wearing prosthesis. The exclusion criteria for this study are the patients with previous prosthodontic treatment and with temporomandibular joint disorders (Table 1).

Table 1: Number of dental student cases.

Table 2: Demographic details of study participants (n=83).

Table 3: Frequency of responses on knowledge related questions (n=83).

Table 4: Frequency of responses on attitude-related questions (n=83).

Table 5: Frequency of responses on practice-related questions (n=83).

Table 6: Percentage distribution of utilization of prosthodontic services at SDOH dental teaching clinic, FNU.

Table 7: Percentage distribution of barriers to utilization of Prosthodontic services at SDOH dental teaching clinic, FNU.

Data management and analysis

Once data was collected, it was entered into MS Excel, and a backup was made online, which the primary investigator and the research supervisors could only access. The collected data was then entered into Epi Info 7.2 software for backup and storage. Relevant codes were used to label the data to increase efficiency. Participant responses were categorized from the questionnaire, which was divided into the 3 main branches for this research: knowledge, attitude, and practice. Furthermore, all answered questionnaires were given a unique code/number to reduce biases.

Ethical considerations

CHHREC of the FNU approved the study (Reference: 019.22). Confidentiality of participants were strictly ensured by removing any form of identifier such as name or student identification number. The purpose and nature of the study were explained to the participants verbally via telephone and face-to-face to patients, and voluntary informed consent was obtained, respectively, prior to the commencement of the interview. Participation in the study was voluntary and participants were informed of their right to participate or withdraw their participation during the course of the study. All consent forms

were kept in a sealed envelope and stored in a locked file cabinet, and the information from the questionnaires was kept secured and password protected. This study had a very low risk of harm. However, proper management was taken of the data being collected, ensuring no participant information was revealed. These documents of the study would be retained for 1 year after which it would be destroyed by shredding.

The sample as shown in Table 1 consisted of 40.97% male, 50.60% female and 8.43% non-specific respondents. It was noted that 61.45% of the participants were between the ages of 61-70 years old while 16.87% were from 51-60 years old. Regarding educational background, 44.58% of the participants stated that they had only attended primary school. In terms of ethnicity, 46.99% of the participants were Fijian of Indian descent (FID) while 44.58% were I-Taukei. Furthermore, 40.96% of the participants were from sub-urban residential areas, while 38.55% were from urban (Table 2).

Table 3, illustrated below, highlights the assessment of knowledge in frequencies among patients who participated in the study. There was 87.95% of participants who felt there was a need to replace missing teeth, whereas 3.61% didn’t agree. 40.96% of the participants chose to eat as the main reason for replacing missing teeth, while others chose appearance 15.66%, speaking 15.66% together with 22.89% of participants who thought it was not important to replace teeth. Of the 83 participants, 98.80% had missing teeth, from which 54.22% had those missing teeth replaced and 42.17% did not. Furthermore, 54.22% of participants who had replaced missing teeth were wearing removable prostheses, with 39.76% removable complete dentures and 16.87% removable partial dentures. From the 42.17% who did not replace the missing teeth, the most common response was inadequate knowledge (9.64%), followed by no time (14.46%). Of the participants who had missing teeth, most had more than 15 missing teeth (44.58%). In terms of being aware of prostheses, the majority of participants chose to know about removable partial dentures (43.37%), while 34.94% knew about complete removable dentures, and 13.25% had no information. In terms of denture longevity, participants were asked how long a denture should last, whereby 34.94% stated more than 5 years, while 24.10% stated 2-3 years and 18.07% for 4-5 years. When asked about the relevance of denture review, 67.47% of the participants stated yes. Furthermore, 90.36% of respondents were not aware of dental implants, while 9.64% knew (Table 3).

Table 4, illustrated below, reveals the participant's attitudes towards prosthetic treatment. Most participants (78.31%) highlighted the need for immediate replacement while 2.41% disagreed, and 19.28% were not sure what to say. Additionally, participants were also asked multiple questions regarding their existing dentures, whereby 65.06% of the participants stated they could eat with their present dentures, while 19.28% disagreed. Moreover, in terms of speech, 72.29% of the participants said they were satisfied, while 16.87% said they were not satisfied. Additionally, based on the aesthetic of the dentures, 77.11% of participants mentioned yes while 14.46% stated no. Furthermore, when asked about discomfort with dentures, 60.24% of the participants stated no while 28.92% said yes. To add on, 68.67% of the participants stated they only made dental visits for pain, while only 9.64% mentioned making dental-related visits regularly. Based on visitations to a dentist being an easy process, 56.63% responded in favour, while 42.17% stated it was not. When it came to knowing if regular visits to the dentist were important, 75.90% of the participants agreed, while 15.66% disagreed (Table 4).

Table 5 illustrates the frequency of the participants on practice-related questions where they were asked about their preferred mode of replacement for missing teeth. 69.88% of the participants preferred removable dentures while 20.48% did not know the options. When looking at the mode of cleaning prostheses, 55.42% used a brush and toothpaste, whereas 30.12% preferred the rinse method. Moreover, when asked about wearing a denture, 65.06% wore one, while 34.94% stated they did not. Based on the type of prosthesis, 62.65% of the participants mentioned about removable dentures, while 4.82% did not know. 28.92% of the participants wore their dentures from a year to 5 years, whereas 18.07% wore less than a year and 14.46% from 5-10 years. In relation to cleaning of dentures, 37.35% said they cleaned it twice a day. Not only were they asked how often they clean their denture, but also which part they clean it which highlighted that 59.04% of the participants cleaned from front and back. When asked if cleaning their denture is the same as natural teeth, 61.45% stated yes, while 27.71% mentioned no, with 10.84% stating they did not know (Table 5).

Table 6, presented below, shows the distribution of the utilisation of prosthodontic services at the dental teaching clinic. From the questionnaire, several questions were picked to determine the utilisation of services. It has been highlighted that 54.22% of the participants had missing teeth, from which only 78.31% agreed that the immediate need for replacement is important, while 19.28% did not know whether to replace or not. Moreover, 68.67% of patients visit the dentist when they have pain, and 75.90% feel that regular visitations to the dentist are important. From this, we can deduce that even though patients have missing teeth and feel like replacement is important, they visit the dentist when they have pain. Therefore, under-utilization of the services provided to prevent dental pain. In addition, the participants were also asked their preferred mode for tooth replacement; 69.88% had chosen removable, while 20.48% didn’t even know the options. When participants were asked how often denture hygiene is performed, 37.35% stated twice a day while 26.51% of the participants mentioned more than twice. This shows us that participants didn’t know the options for tooth replacement which led to under-utilization of prosthodontic services (Table 6).

Barriers prevent utilisation of prosthodontic services which is demonstrated in Table 7. Participants were asked if there was a need for tooth replacement; 87.95% said there was, while 8.43% did not know. When considering the importance of tooth replacement, 40.96% were for eating while 22.89% stated it was not important. Furthermore, the main reason for not replacing teeth with 14.46% was no time. Therefore, while the majority of the participants agreed that there is a need for replacement, the majority were replaced due to eating, while the other participants thought it was not important, with the main reason being having no time. This becomes a barrier to utilize services for prosthodontic rehabilitation. When asked which prosthesis they are aware of, 43.37% of the responses were removable partial dentures. Furthermore, when asked if review was important, 67.47% said it was while 16.87% of the participants stated no. Asking about fixed prostheses, 90.36% of participants did not know about them. It was also noted that 65.06% of the study group was wearing dentures while 35.94% did not. This inadequate knowledge of the type of prosthesis is a major contributor to a barrier to the under-utilization of services. It was also seen that 34.94% of participants were not wearing a denture, and it was also generally seen that 16.87% did not agree that review was important. This is the majority contributor to barriers affecting the proper utilisation of prosthodontic services (Table 7).

This study assessed the knowledge, attitude, and practice of patients towards prosthodontic rehabilitation. It revealed that the majority of the patients knew about their missing teeth, but only a certain percentage (39.76%) had replaced them. This was mainly due to financial reasons (9.64%) or lack of time (14.46%). It also showed that the majority only knew about removable prostheses, whilst only a few knew about fixed prostheses. Furthermore, this study also focused on the utilisation of prosthodontic services among patients. This study showed that the majority did not fully utilise the services provided. The outcomes of this research showed the knowledge profile of the study population was insufficient with respect to the placement of lost teeth. The probable reason could be that 44.58% parts of the population just received primary education. This was similar to a study by Marcus et al, whereby it was found that lack of education is correlated to a lack of awareness about the importance of oral health, and the consequences of neglect appear to constitute a barrier to using dental health care services [10]. The study revealed that 99% of participants had missing teeth, with 45% having more than 15 teeth missing. It was also seen that 54.22% of them had favourable attitudes toward replacing missing teeth. This conclusion was comparable to that of Nirmala et al, who found that the survey respondents were aware of the need for tooth replacement [11]. Mostly because of inadequate knowledge, no time and economic reasons, the majority did not receive therapy [12]. In a study by Shetty et al, the main reason for not replacing the missing teeth was no felt need for the participants to replace missing teeth [13]. Contrasting results were reported in an earlier study conducted by Reddy, in which financial constraints were the least common reason to replace missing teeth and inadequate knowledge was the most common reason for non-replacement [14]. The results showed that individuals' attitude profiles revealed that 69% of participants visit the dentist when they experience pain, while 10% have regular dental visitations. They were also asked if regular dental visits were important; 76% said it was important, while 16% didn’t. This was due to coming to the dentist being an easy process, thus advancing caries progress and eventually leading to tooth loss. In another study, Pallegdara & Ekanayake came to the conclusion that altered perceptions brought on by advancing age, such as the belief that one is too old to adapt to dentures and artificial teeth and a lack of interest in appearance, maybe a factor in people's reluctance to replace missing teeth as they age [9].

According to responses on denture cleanliness care, 81.93% of respondents had a positive outlook and believed that maintaining prosthesis hygiene was crucial. In comparison to Amjad & Aziz (2014), reported similar outcomes from the study undertaken in Pakistan. When the question of prosthesis maintenance was posed, the authors reported receiving a 97.5% positive response [15]. The participants were asked how often they perform denture hygiene, the majority answered they clean twice a day (37%) while some said they cleaned more than two times a day (27%). Utilization is conceived as the received amount of care; the most common measure is the annual number of dental visits per person. Usually, there is a presumption that a high level of utilization in a population has a positive correlation with oral health. Other studies suggested that dental treatments may be performed as a result of iatrogenic injuries and are also related to the so-called supplier-induced demand [16,17]. Oral health is also likely to affect utilization in a reverse relationship, meaning that good oral health is closely related to a high level of utilization of dental services. Several studies indicate that edentulism per se is related to a low level of utilization [16-18]. Extensive prosthodontic treatments will require maintenance. The need for maintenance is usually higher for removable prostheses than for fixed prostheses, and several studies indicate excellent long-term survival rates following treatment with fixed prostheses [18]. The process, from the recognition of a need to its utilization, can be influenced by social and economic factors. Evidence suggests that the use of dental services may be adversely affected by the current national economic downturn. Even in systems that offer financial assistance, people with low incomes use dental services less frequently and spend less on them than people with higher incomes [19]. The most common reason given for not getting dental care is the cost. However, research shows that offering free or greatly reduced services has little impact on uptake. On the other hand, attitudes regarding expenditures may be associated with the use of dental treatment [20]. Moreover, it can be seen when comparing to this study, it was seen that participants only visited the dentist when they had pain, this could relate to their financial status. Regular visits often take time from a person's day, which is spent at work. Therefore, a fast solution to a toothache is a route taken; this is evident from the majority of the participants having missing teeth. The most common barriers to receiving dental care, according to the caregivers in this study by Alfaraj et al. were lack of time on their part, poor design, and environment of the dental clinic, transportation issues, the special healthcare needs person's medical health status, which prevents him/her from receiving immediate dental care, and the dental clinic's location is too far from the intended special healthcare needs person. Obstacles included unfriendly and inexperienced dental staff, cost and financial difficulty, fear of the dentist, communication problems between the dentist and the person with a special need, difficulty getting dental appointments, and a lack of dental care facilities to accommodate people with special needs [21]. These barriers are congruent with those reported by, Al-Shehri and Alumran which can be grouped into those relating to special healthcare needs individuals’ ability to physically access dental facilities, inability to afford dental services due to high costs of treatment and insufficient financing for dental treatment, and the preparedness and willingness of dentists and dental nurses to treat special healthcare needs individuals [22,23]. Patients were unable to take advantage of treatment because they were unaware of the several prosthodontic treatment alternatives available. According to studies by Menezes M, Van Twillert and Zitzmann dental camps and prosthodontic outreach programs are a potential strategy to alter attitudes, raise awareness, and impart knowledge about the various options for replacing missing teeth [24-26].

Limitations of the study

Some limitations that were identified while undertaking the study were: participation level was limited despite the sample size of the study; the findings of this study cannot be applied to the entire Fijian population because it was a cross-sectional study carried out in one of the country's dental teaching clinics; this study was likewise a survey that relied significantly on participants' recollection and the responses they supplied when filling out the questionnaire; post Covid-19, patients were reluctant for a face-to-face interview; seeking consent over the phone when unable to meet the patients face-to-face; due to the nature of the study data collections method, it was done based on participants’ availability.

Knowledge, attitude, and practice regarding prosthodontic rehabilitation were poor among the study participants. Financial constraints and lack of time were the main factors for not undergoing prosthodontic rehabilitation. This study showed participants had inadequate knowledge based on oral health and the various prosthetic treatment options available, many of which had more than 15 missing teeth. Moving on, attitude showed to be partially known and practised. Many of them knew why they had gotten a prosthesis and that replacement was important. In terms of practice, this was seen as insufficient as participants didn’t know how to perform denture hygiene as well as the frequency of it. In conclusion, the findings show that the majority of patients were between the ages of 60 and 70, and nearly all of them had missing teeth. Based on these findings, we can conclude that patients can have their teeth replaced if they have the proper mindset and knowledge to comprehend the various treatment options available. Since many participants had little knowledge about the types of prostheses available, their choice was confined to the ones they had heard about or seen previously. It was also observed that patients' main concern for prostheses was eating rather than oral health or speech, as they only visit the dentist when there is pain.

I would like to express my deep gratitude to Meenal Nand and Suneil Nath my research supervisors and co-authors, for their guidance, encouragement, and useful critiques of this research. I would also like to pay my tribute to the Late Dr. Temalesi King for her continuous support as the Course Convener for this study. All authors declare no competing or potential conflicts of interest. 

1. Akeel R. Attitudes of Saudi male patients toward the replacement of teeth. J Prosthetic Dent. 2003; 90: 571-577.
2. Emami E, de Souza RF, Kabawat M, Feine JS. The impact of edentulism on oral and general health. Inter J Dent. 2013.
3. Leles CR, Freire MD. A sociodental approach in prosthodontic treatment decision making. J Applied Oral Sci. 2004; 12: 127-132.
4. Hugoson A, Koch GK, Gothberg C. Oral Health of individuals aged 3-80 years in Jonkoping, Sweden during 30 years (1973-2003). II. Review of Clinical and radiographic findings. Swedish Dental J. 2005; 29: 139-155.
5. Brown, D. W. Complete edentulism prior to the age of 65 years is associated with all?cause mortality. J Public Health Dent. 2009; 69: 260-266.
6. Riaz W, Aslam A, Aziz S. Dental Prosthesis; Assessment of grades of failures of conventional fixed dental prosthesis based on severity. The Prof Med J. 2018; 25: 1261.
7. Shigli K, Hebbal M, Angadi GS. Attitudes towards replacement of teeth among patients at the Institute of Dental Sciences, Belgaum, India. J Den Edu. 2007; 71: 1467-1475.
8. Gupta S, Mantri SS, Bhasin A. Knowledge and attitude towards prosthodontic rehabilitation and utilization of dental services by central India population of Jabalpur city, India. Annals of Medical and Health Sciences Research. 2018.
9. Pallegedara C, Ekanayake L. Tooth loss, the wearing of dentures and associated factors in Sri Lankan older individuals. Gerodontology. 2005; 22: 193-199.
10. Marcus PA, Joshi A, Jones JA, Morgano SM. Complete edentulism and denture use for elders in New England. J Prosthetic Dent. 1996; 76: 260-6.
11. Nirmala SV, Mallineni SK, Nuvvula S. Pre-maxillary hypo-hyperdontia: report of a rare case. Rom J Morphol Embryol. 2013; 54: 443-445.
12. Raj N, Reddy N, Japatti S, Thomas M, Uthappa R. Knowledge, attitudes towards prosthodontics rehabilitation and utilization of dental services among Songadh and Amargadh population. J Dent Med Med Sci. 2014; 3: 1-6.
13. Shetty MS, Panchmal GS, Shenoy KK. Awareness toward replacement of teeth, duration of use, and maintenance of dental prosthesis among adult rural population in Mangalore Taluk. J Interdisciplinary Dent. 2019; 9: 15.
14. Reddy RN, Elamin EI, Vempalli S, Al Sanabani F. Perception and awareness of prosthodontic rehabilitation among Jazan population in the Southern Region of Saudi Arabia. Glob J Med Res. 2016; 16: 1-8.
15. Amjad F, Aziz S. Trends, Awareness, and attitudes of patients towards replacement of missing teeth at university collage of dentistry. Pakistan Oral Dental J. 2014; 34.
16. Mc Grath C, Bedi R. Can dental attendance improve quality of life?. British Den J. 2001; 190: 262-265.
17. Richards W, Ameen J. The impact of attendance patterns on oral health in a general dental practice. British Dental J. 2002; 193: 697-702.
18. Narby B, Kronstrom M, Soderfeldt B, Palmqvist S. Prosthodontics and the patient. Part 2: Need becoming demand, demand becoming utilization. Inter J Prosthodontics. 2007; 20.
19. Manski RJ, Moeller JF, Maas WR. Dental services: an analysis of utilization over 20 years. J American Dental Association. 2001; 132: 655-664.
20. Griffitts TM, Collins CP, Collins PC. Mini dental implants: an adjunct for retention, stability, and comfort for the edentulous patient. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology. 2013; 100: 81-84.
21. Alfaraj A, Halawany HS, Al-Hinai MT, Al-Badr AH, Alalshaikh M, Al-Khalifa KS. Barriers to dental care in individuals with special healthcare needs in Qatif, Saudi Arabia: a caregiver’s perspective. Patient preference and adherence. 2021; 69-76.
22. AL-Shehri SA. Access to dental care for persons with disabilities in Saudi Arabia (Caregivers' perspective). J Disability Oral Health. 2012; 13: 51.
23. Alumran A, Almulhim L, Almolhim B, Bakodah S, Aldossary H, Alakrawi Z. Preparedness and willingness of dental care providers to treat patients with special needs. Clinical, cosmetic and investigational dentistry. 2018; 10: 231.
24. Menezes M, Aras M. Prosthodontic awareness and fulfillment of prosthodontic need in rural areas of Goa. J Indian Dent Ass. 2009; 11: 368-373.
25. Twillert SV, Postema K, Geertzen JH, Hemminga T, Lettinga AT. Improving rehabilitation treatment in a local setting: a case study of prosthetic rehabilitation. Clinical Rehabilitation. 2009; 23: 938-947.
26. Zitzmann, NU, Staehelin K, Walls AW, Menghini G, Weiger R, Zemp Stutz E. Changes in oral health over a 10?yr period in Switzerland. European J Oral Sci. 2008; 116: 52-59.