Green Dental Environmentalism among Students and Dentists in Greece

Abstract

Ηuman sustainability in dental enterprises, as in every workplace, is connected to air and water quality, eco-friendly and naturally designed working spaces, and the culture of the 4Rs. The purpose of this study was to assess pro-environmental behavior, as well as knowledge of preferences for circular economies and green building construction, among a sample of dental students and dentists in Greece. We further assessed the factors influencing their choices. Students (N1 = 93) and dentists (N2 = 126) filled in e-questionnaires from April to December 2022. The data revealed that both students and dentists lack knowledge about the circular economy (N1 = 67.74%, N2 = 68.25%), EU regulations on amalgam disposal (N1 = 64.51%, N2 = 58.73%), and plastic recycling (N1 = 76.34%, N2 = 76.98%); meanwhile, they do recycle at home (N1 = 80.64%, N2 = 82.54%) and have participated in voluntary environmental initiatives (N1 = 58.06%, N2 = 66.66%). Gender influences the importance of factors related to green dental practices, with women students being more likely to agree that increased costs for network changes (p = 0.02) and poor wastewater management (p = 0.01) are significant. Students from urban areas are more likely to give positive answers to questions related to the lack of state financial support (p = 0.02), low levels of green design in buildings (p = 0.03), the negligible direct financial benefits of green dental offices (p = 0.04), the negligible reputational benefits of green dental offices (p = 0.02), and the lack of continuing education training seminars on green dentistry (p = 0.05). For dentists, no significant relationships were observed, except for a weak positive relationship for the increases in costs due to changes related to utility networks (p = 0.08), while increases in waste energy (p = 0.12) and the waste of dental materials (p = 0.19) seemed significant only for dentists in urban areas. Women dentists were more likely to answer positively regarding wasting energy (p = 0.024) and the use of unapproved disinfection products (p = 0.036). The findings contribute ideas and solutions for green dental practice buildings and sustainable behaviors through educational activities and regarding the social aspects of factors such as age, experience in dentistry, gender, and urbanism. This study also provides a basis for future multi-disciplinary research on dental quality assurance, the psychology of environmentalism, economics, and behavioral science in dentistry.

1. Introduction

In every workplace, human sustainability is closely connected to the quality of establishments, the accessibility of green and blue spaces, and safety [1]. Incorporating natural environments into human work settings with innovative architectural designs and sustainable construction materials and energy resources plays a serious direct and indirect role in health and wellbeing [2,3]. Although it has long been understood that green work settings play an important role in both human [4,5,6] and ecosystem health [3], it is only recently that these relationships have been specifically investigated to adapt sustainable planning and land use [6,7,8] to several social and environmental challenges [9], such as urban deprivation, biodiversity loss, pollution, and climate change [10,11,12,13]. Furthermore, human-centric designs for building environments enhance their occupants’ satisfaction and health and emphasize sustainable lifestyles [3,14,15].

It is well-documented that energy and material resources are diminishing in all aspects of human activities, or that they are consumed at a faster rate than they can be replenished [3,11]. Actions have already been taken to address issues related to green establishments that connect a physical setting with the smart use of construction materials and esthetics to provide sustainable workplace environments that support human and natural resources [4,5]. Since the beginning of this century, stakeholders and governments worldwide have been discussing using a circular flow of energy instead of a linear one to sustain resources [7]. The UN environment program describes the “Environmental rule of law” that combines essential legislation with environmental needs. It provides the basis for improving environmental strategies at the governmental level. Under this initiative, environmental sustainability reflects universal moral values and ethical norms of behavior and relates to fundamental human rights and obligations [16]. Furthermore, the “Roadmap to a Resource-Efficient Europe” provides a critical approach to the use of resources for environmental reasons but also for resource efficiency and security, employment, competitiveness, and human development [8]. It was additionally highlighted that functional, safe, and high-quality products should be more efficient, affordable, and long-lasting. They should be further designed for reuse, repair, or high-quality recycling. The philosophy of the four Rs (reuse, repair, rethink, recycle), or the “waste hierarchy” as it is known, is incorporated in various ways in CE national legislations [8]. In March 2020, the European Commission adopted the new Circular Economy Action Plan (CEAP). This is part of the European Green Deal, Europe’s new agenda for sustainable growth [9]. This deal will assist the transition to a circular economy (CE). The consequences of this transition will reduce the pressure on natural resources and provide sustainability to all stakeholders [9].

In this context, the design and construction of green buildings is a new research focus motivated by the need for human wellbeing and sustainable resources in the health sector [2,3,10]. The circular philosophy of dentistry is currently emerging as a theme in the research literature, providing knowledge and tools for information sharing and enhancing environmental actions [10,17,18,19]. A significant aspect of this field-specific discussion concerns providing better quality and sustainable dental services by using new processes and slow dentistry workflows in an esthetic, naturally designed environment; it also aims to offer digital solutions, provide innovative resource analysis and building constructions that guarantee less waste [6], improve skills and current knowledge related to this theme, [18,19,20] and, ultimately, provide better quality of life for all, up to 2050 [13]. In dentistry, as in other fields, the physical setting is linked to an employee’s ability to physically engage with the workplace [12]. A healthy dental workplace atmosphere positively influences individual employees’ behavior, enthusiasm, creativity, motivation, and efficiency [15,20], and, on the other hand, their desire to quit [21].

The World Green Building Council defines a green building as a building that “in its design, construction or operation, reduces or eliminates negative impacts, and can create positive impacts, on our climate and natural environment” [10]. Stakeholders in the construction industry are focusing on making modern buildings and their internal systems more sustainable by saving energy [3,19,20,21,22,23], water [24], human working hours [25], costs [26,27,28,29], and resources [3,30]. This attitude has positive impacts for a building, such as reduced carbon emissions [23], water and energy efficiency, the use of natural sunlight, exposure to nature, clean air circulation [31], reduced noise impact [32,33], higher returns in operating costs over five years, and higher investment returns with an asset value that can reach approximately 7% [26,27,28,29,30]. As a consequence, these constructions can facilitate sustainable dental practices that focus on indoor air and water quality, employees’ ability to socialize in a relaxing environment made from recycled materials, employees’ ability to exercise in the building due to long hours of continuous work, lighting and acoustic quality, safe waste disposal, and security issues [2,3,11,33].

So far, little is known about the behavior of dental professionals and their willingness to adapt to this sustainable office design and culture and the possible factors influencing their choices regarding green building issues or the “four Rs” philosophy [17,18,19,20,34]. The pro-environmental behavior of dentists has only recently emerged as a research theme [19]. This paper contributes to the theme, first by establishing 30 factors that affect the development of eco-friendly dental practices. These factors derive from 40 preliminary factors described in the relevant literature as affecting three main domains: “Sustainable Building Designing and Planning” (SBDP), “Education and Awareness of Environment Sustainability (EAES)”, and “Economic aspects relating to costs of construction and function of environmentally Sustainable Dental Practices” (ESDP) [34]. Second, we present an incidence proposal of the 13 factors we identified as being significantly important for environmental sustainability in dentistry (ESD). For these purposes, we used the method of a questionnaire survey of both students and professionals in the field. Third, we analyze the relationships between and the impact of different critical green building construction factors on the choices and behaviors of participants. We finally present some recommendations, development strategies, and educational proposals for all stakeholders.

2. Background

2.1. Pro-Environmetal Behaviors

Environmental problems correlate with human choices and behavior. Therefore, changes in behavior are necessary to improve the current status of environmental ethics. Pro-environmental behavior is behavior that minimizes the negative impact of individuals’ behavior on the environment [35]. It plays an important role in controlling energy resources and carbon footprints and protecting environmental sustainability [36]. In the literature, there are many labels similar to the term “pro-environmental behavior”, such as “environmental behavior”, “ecological behavior”, “environmentally friendly behavior”, “eco-friendly behavior”, “sustainable behavior”, “green behavior”, “conservation behavior”, “environmental action”, “responsible environmental behavior”, “ecological responsible behavior”, “environmentally responsible behavior”, “pro-ecological behaviors”, and “environmentally conscious behavior” [37]. All of these different terms have some common ground. They all essentially involve reducing resource use [38], recycling [39], or environmental volunteering [36]. They are also affected by personal values and ethics. They are further explained by psychological theories [36]. Understanding pro-environmental behaviors in healthcare has recently become a hotspot in research. Since 2012, the number of relevant studies has increased significantly [36]. Interest in pro-environmental behavior has mainly focused on the following aspects: (a) the definition and explanation of the influencing factors or results of pro-environmental behavior [40,41], (b) the relationship between pro-environmental behaviors and social norms [42], (c) the connection between pro-environmental behaviors and employees’ wellbeing [43], and (d) the design of models of pro-environmental behavior to introduce voluntary pro-environmental behaviors to employees [44]. The research conducted so far is of great significance to our systematic understanding of the tools and methodologies used to study pro-environmental ideas. However, academic research on pro-environmental behaviors in healthcare settings and especially in dental practices is in an active development stage and needs further exploration.

2.2. Theories of Pro-Environmental Behavior

The following theories are those most commonly applied in the study of pro-environmental behavior:

(A) Psychological theories. These involve the internal psychological processes undergone by individuals before they take action. The most representative ones are: (a) the theory of planned behavior [45,46], which investigates the impact of attitudes, subjective norms, and perceived behavior control on individuals’ intention to engage in pro-environmental behavior [47,48,49], and (b) the norm activation theory [48]. According to this theory, personal norms such as awareness of consequences and responsibility [49] may control behaviors [50,51,52]. As such, an individual who believes that he has a moral obligation to protect the environment will undertake the corresponding actions [49,53].

(B) Sociological theories. These theories suggest that social situational factors may influence individual behaviors [54]. Members of a social network, such as dentists, inevitably interact with other members of the same network, influencing one another when making decisions or taking actions [55]. Through various kinds of social interaction, individuals obtain useful information [56], improve their understanding of environmental protection issues, and promote environmental sustainability [36].

(C) Economic theories. In this case, more attention is paid to the influence of external factors such as prices, costs, and income when studying the pro-environmental behavior of individuals. These theories provide a more realistic perspective on behaviors and choices [57]. They further suggest that people are rational and pursue their best interests. Thus, economic incentives are an effective way to promote sustainable pro-environmental behaviors [58,59].

Despite the research that has so far considered pro-environmental behaviors in many scientific fields, none of the extant literature adequately explains human attitudes towards environmentalism and sustainability. Thus, interpreting pro-environmental behaviors using a single theoretical or ethical approach should be limited [36,48]. All theories should provide complementary explanations and be revised for specific fields and practical situations. We should also keep in mind that individuals are not always rational when taking decisions. They often deviate from the hypothesis of rational choice [59]. This brings us to the hypothesis that a combined theoretical approach should be used in relevant research methodologies to acquire the greatest amount of information without bias.

3. Research Methods

3.1. Identification of Factors Influencing Sustainable Design and Planning

The aforementioned theories have been extensively used in the research of green building development [34,60,61]. Therefore, it has already been reported that certain factors could influence the buyers of green estates (green residential buildings, or GRBs). People usually decide on their future homes based on socio-environmental data [62] and factors related to resources [63,64,65,66] and capacity [67,68]. Τhese elements consist of 3 different dimensions that interact with each other and include 64 basic influential factors, which have been addressed in previous studies [12,13,14,15,16,17,18,34,36,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,64,65,69,70] (Figure 1).

3.2. Methodology of Designing the Study Questionnaire

In this study, we used the questionnaire study technique, which is a systematic method for data collection. Furthermore, it has previously been used to collect professional views on sustainable construction research [34,61,65,66,67,68,71,72]. We used the technique across two rounds in our study. In the first round, we formed a list of the 64 factors previously associated with GRBs to determine the significance of their impact on stakeholders in the dental field. We gave the list randomly to thirty students from the Department of Dentistry in the School of Health Sciences of the National and Kapodistrian University of Athens and to thirty dentists who were selected randomly from the personnel of the Department of Dentistry and through social media advertisements. Participants in the first round agreed to complete the list in person within the settings of the dental school, providing explanations for and discussions of the comprehensibility of the factors. Factors that were not mentioned at all in the first round were excluded from further exploration. We then kept 30 factors related to green dental buildings (GDBs) (Figure 2), which were mentioned by participants in the first round, regardless of their level of significance or the frequency of answers, and we used them to form the final questionnaire used in the study.

When designing the final questionnaire to be used in the study, we addressed the following research questions: (1) what are the main attitudes of dental students and dentists towards recycling, pro-environmentalism, and volunteering? (2) How do demographic factors influence their pro-environmental behaviors and choices regarding the circular economy and the construction of green dental buildings (GDBs)? (3) Which practices most strongly lead dentists to perceive the importance of constructing GDBs?

The steps we followed to complete the final questionnaires can be seen in Figure 3.

Two categories of participants participated in the second round of the data collection: (a) undergraduate students of the Department of Dentistry of the School of Health Sciences of the National and Kapodistrian University of Athens, and (b) dentists working in the vast metropolitan area of Athens, in the Prefecture of Attica, Greece. Two digitally formed questionnaires were designed according to the previously mentioned methodology, incorporating the thirty factors for green dental buildings (GDBs). Participants were given a specific QR code to provide direct access through smartphones; these were distributed accordingly to (a) undergraduate dental students (inclusion criteria: undergraduate students) and (b) professional dentists, who were active members of the Athens Regional Dental Association (inclusion criteria: active members of the association, working in Greece).

The questionnaire for students (Appendix A) investigated: (a) the demographic characteristics of the sample (Part A_Q1–Q4), including gender, year of study, place of residence, and the educational level of parents, which have been described elsewhere as possible correlating factors [6,25,73,74]. (b) Current environmental volunteering and awareness of legislation (Part B_Q5–Q9), so that participants could spontaneously respond to questions regarding their current eco-friendly behaviors and we could further discuss their intentions to engage in future pro-environmental behaviors [44,45]. (c) The importance of 30 factors influencing pro-environmental attitudes (Part C_Q10.1–Q10.30), revealed in the first round of the survey. (d) The estimation of educational needs and participants’ proposals (Part D_Q11–Q12) according to the factors identified in the first round [58,59,65,66]. Accordingly, the questionnaire for dentists (Appendix B) reported on: (a) the demographic characteristics of the sample (Part A_Q1–Q7) [6,25], (b) pro-environmental behaviors and attitudes towards environmental volunteering and awareness of legislation (Part B_Q8–Q13), (c) the importance of factors influencing pro-environmental attitudes (Part C_Q14.1–Q14.30) and (d) the estimation of educational needs and participants’ proposals (Part D_Q15–Q16) based on the findings of the first round of the survey, as described for Appendix A. Parts A and B had multiple choice answers, and part C required answers in terms of a 5-point Likert scale, where 1 = “extremely insignificant”, 2 = “relatively insignificant”, 3 = “neutral”, 4 = “relatively significant”, and 5 = “extremely significant”. Part D contained open-ended questions where participants could offer their brief opinions and suggestions on the topic.

The questionnaires included an introductory message describing the purpose of the study. It was further noted that participation was voluntary, and confidentiality was guaranteed. Participants had the right to refuse to participate. Consent was obtained by asking participants to confirm that they agreed to complete the questionnaire by marking a “Yes, I agree to participate” box. The Board of Ethics of the Department of Dentistry gave approval (No 39521/20-4-2022). Accordingly, for participating dentists, members of the Athens Regional Dental Association of the metropolitan area of the capital, Athens, the relevant license was obtained by the scientific committee of the association (No:2660/08.12.2022).

The design and validity of the questionnaires were further examined by 15 participants from each subgroup (students and dentists), while an independent panel of 3 experts (professors of the Department of Dentistry) reviewed and revised the final version. They first filled in the questionnaires and discussed them in person and then in a group with all the other experts and members of the research team. All questions were then confirmed to be relevant to the topic. No issues regarding misconceptions of the terms or the expressions used were mentioned. To submit the form, all questions needed to be answered. Only one submission was allowed. The questionnaires required approximately 12–15 min to complete. All undergraduate students were given the same access and opportunity to complete the questionnaire. The secretariat of the department sent the link and relevant instructions for its completion three times (once per week). Accordingly, the questionnaire for dentists was sent from the secretariat of the association. The questionnaires remained open for three months.

3.3. Data Analysis

Data analysis included descriptive statistics and thematic analysis [75,76]. In the thematic analysis, the deductive approach was used [76] to analyze the information collected from the participants regarding the green dentistry issues preconceived by the researchers as a result of the current state of knowledge on the topic based on the literature review. Since the practices of green dentistry are relatively new in Greece, we opted for this approach to acquire a better understanding of dental students’ and practicing dentists’ knowledge of and attitudes towards these rather innovative concepts. After reviewing the information collected through the replies, the main common features were recorded for each group of respondents to identify patterns and to form the main points raised with regards to green dental practices. The methodology used is an adaptation of the six-step process proposed by Brown and Clarke [75].

In the statistical analysis, the frequency distribution of all variables was examined (demographic information and ESD factors). Gender (males/females) and place of residence (urban/non urban) were cross tabulated as dependent variables with a series of independent variables related to knowledge, perceptions, and the importance of factors for ESD, such as the principles of the circular economy, recycling practices, the use of environmentally friendly consumables in dental practices, green design standards in dentistry, and training in green dentistry practices, to assess the presence of a statistically significant relationship with the Chi square test and post hoc testing at the 95% significance level. Regarding the use of single-item scales vs. multi-item scales, there are arguments for both sides. In this survey, the single-item approach was used with some validation questions to establish the accuracy of the responses given for some topics. According to researchers, single-item scales are as reliable as multi-item scales and can be used in academic surveys measuring attitudes towards new practices, as long as the single items have a clear meaning and describe a specific object or issue [77], as is the case in our study. We then proceeded to attempt to capture the attitudes of a sample of dentists and dental students using a cross-sectional design to establish a basis for further actions in green dental practice.

All analyses were performed using the IBM SPPS Statistics (v.26) predictive analytics software.

4. Results

A total of 93 out of 520 dental students in their 2nd, 3rd, 4th, and 5th years of undergraduate study participated in the study (response rate of 17.88%), and 126 dentists participated out of the 6500 members of the association (response rate of 1.94%). The response rate of the practicing dentists seems rather low; however, it should be noted that, of the 6500 registered dentists in the association, the vast majority of practitioners do not respond to research-driven initiatives on professional issues [6,25]. Moreover, being registered with the association does not necessarily correspond to having a dental practice, as many members do not practice dentistry (for the year 2022, 27.8% of the registered members do not practice dentistry, according to the association). Additionally, given that environmentally friendly dental practices are currently not well known to most practicing dentists, we can assume that the survey respondents represent the small fraction of dental practitioners who are environmentally aware and may consider these issues in their practices. In other words, the results of the survey correspond to very few members of the association, rather than the whole cohort; this constitutes an important finding, which could be used to guide future efforts to familiarize dentists with green dental practices. Furthermore, when recording practices and opinions, there is no need for a correlation between responses (which is also called internal consistency or reliability) [6,25,78].

In the sample of dental students who participated in the survey (N1 = 93), 34 (36.6%) were men and 59 (63.4%) were women. The distribution according to semester of studies was as follows: 60 (64.5%) students were currently attending their 4th semester of studies (2nd year), 21 (22.6%) their 6th semester (3rd year), 5 (5.4%) their 8th (4th year), and 7 (7.5%) were in their 10th semester (5th year). The majority lived in Athens or other urban areas, with 61 urban students (65.6%) compared to 32 (34.4% of the total sample) students who live in non-urban areas or on the islands of Greece. Regarding the distribution of the practicing dentists in the study sample (N2 = 126), 46 (36.5%) were men and 80 (63.5%) were women, 96 (76.2%) resided and practiced dentistry in Athens or other urban areas and 30 (23.8%) were situated in rural areas of the Prefecture of Attica.

The gender ratio of 1:2 (man:woman) in both groups of the study corresponds to findings from relevant studies, while the participation and response levels are similar to those of other online surveys (65–70% in women and 25–30% in men) [25,74,79]. There is also a general consensus that there is a gender disparity in participation in online surveys, with women participating more than men [80]. The demographic characteristics of the sample are presented in

Table 1. Demographic characteristics of the study samples: dental students and practicing dentists.

	Gender		Place of Residence		Semester of Studies
	Males N (%)	Females N (%)	Urban N (%)	Rural N (%)	10th N (%)	8th N (%)	6th N (%)	4th N (%)
Students	34 (36.6)	59 (63.4)	61 (65.6)	32 (34.4)	7 (7.5)	5 (5.4)	21 (22.6)	60 (64.5)
	Total 93
Dentists	46 (36.5)	80 (63.5)	96 (76.2)	30 (23.8)
	Total 126

.

With regards to questions about recycling, voluntary participation in environmental protection activities, and knowledge of the EU legislation on mercury (Hg) use and plastic recycling within the dental practice, the responses were analyzed according to gender (

Table 2. Pro-environmental behaviors regarding volunteering and knowledge of legislation according to gender for students and dentists. Non-statistically significant p-values were recorded.

Questions Q5–Q9 (Students) and Q8–Q13 (Dentists) and Results According to Gender
Q5. Do you use recycling at home?
	Total		Men		Women
	Students N1 = 93	Dentists N2 = 126	Students N1m = 34	Dentists N2m = 46	Students N1w = 59	Dentists N2w = 80
Yes	75 (80.64%)	104 (82.54%)	27 (79.41%)	40 (86.96%)	48 (81.35%)	64 (80.00%)
No	16 (17.20%)	22 (17.46%)	5 (14.70%)	6 (13.04%)	11 (18.65%)	16 (20.00%)
I prefer not to answer	2 (2.16%)	0	2 (5.89%)	0	0	0
p-value	0.16	0.32
Q6. Have you ever participated in voluntary environmental actions at home or during your studies?
Yes	54 (58.06%)	84 (66.66%)	19 (55.88%)	28 (60.86%)	35 (59.32%)	56 (70.00%)
No	38 (40.86%)	40 (31.74%)	14 (41.17%)	16 (34.78%)	24 (40.68%)	24 (30.00%)
I prefer not to answer	1 (1.08%)	2 (1.60%)	1 (2.95%)	2 (4.36%)	0	0
p-value	0.41	0.13
Q7. Are you aware of what circular economy means in dental practice?
Yes	20 (21.50%)	27 (21.42%)	4 (11.76%)	11 (23.91%)	16 (27.11%)	16 (20.00%)
No	63 (67.74%)	86 (68.25%)	26 (76.47%)	30 (65.21%)	37 (62.71%)	56 (70.00%)
I prefer not to answer	10 (10.76%)	13 (10.33%)	4 (11.77%)	5 (10.88%)	6 (10.18%)	8 (10%)
p-value	0.22	0.24
Q8. Are you aware of the current European Union legislation about mercury use and disposal?
Yes	28 (30.10%)	41 (32.54%)	12 (35.29%)	17 (36.95%)	16 (27.11%)	24 (30.00%)
No	60 (64.51%)	74 (58.73%)	21 (61.76%)	27 (58.69%)	39 (66.10%)	47 (58.75%)
I prefer not to answer	5 (5.39%)	11 (8.73%)	1 (2.95%)	2 (4.36%)	4 (6.79%)	9 (11.25%)
p-value	0.57	0.36
Q9. Are you aware of the current European Union legislation about plastic recycling?
Yes	20 (21.50%)	20 (15.87%)	7 (20.6%)	9 (19.56%)	13 (22.0%)	11 (13.75%)
No	71 (76.34%)	97 (76.98%)	27 (79.4%)	35 (76.09%)	44 (74.6%)	62 (77.50%)
I prefer not to answer	2 (2.16%)	9 (7.14%)	0 (0.0%)	2 (4.35%)	2 (3.4%)	7 (8.75%)
p-value	0.54	0.45

) and place of residence (

Table 3. Pro-environmental behaviors regarding volunteering and knowledge of legislation according to place of origin/dentistry practice.

Questions Q5–Q9 (Students) and Q8–Q13 (Dentists) and Results According to Place of Origin/Dentistry Practice
Q5. Do you use recycling at home?
	Total		Urban Areas		Non-Urban Areas
	Students N1 = 93	Dentists N2 = 126	Students N1urban = 61	Dentists N2urban = 96	Students N1nonurban = 32	Dentists N2nonurban = 30
Yes	75 (80.64%)	104 (82.54%)	48 (78.68%)	80 (83.33%)	27 (84.37%)	24 (80.00%)
No	16 (17.20%)	22 (17.46%)	12 (19.67%)	16 (16.67%)	4 (12.50%)	6 (20.00%)
I prefer not to answer	2 (2.16%)	0	1 (1.65%)	0	1 (3.13%)	0
p-value	0.63	0.67
Q6. Have you ever participated in voluntary environmental actions at home or during your studies?
Yes	54 (58.1%)	84 (66.66%)	35 (57.4%)	62 (64.58%)	19 (59.4%)	22 (73.33%)
No	38 (40.9%)	40 (31.74%)	25 (41.0%)	32 (33.33%)	13 (40.6%)	8 (26.67%)
I prefer not to answer	1 (1.1%)	2 (1.60%)	1 (1.6%)	2 (2.09%)	0	0
p-value	0.76	0.55
Q7. Are you aware of what circular economy means in dental practices?
Yes	20 (21.5%)	27 (21.43%)	14 (22.95%)	17 (17,70%)	6 (18.75%)	10 (33.33%)
No	63 (67.7%)	86 (68.25%)	41 (67.21%)	70 (72.91%)	22 (68.75%)	16 (53.33%)
I prefer not to answer	10 (10.8%)	13 (10.32%)	6 (9.84%)	9 (9.39%)	4 (12.5%)	4 (13.34%)
p-value	0.85	0.19
Q8. Are you aware of the current European Union legislation about mercury use and disposal?
Yes	28 (30.10%)	41 (32.54%)	19 (31.14%)	34 (35.42%)	9 (28.1%)	7 (23.33%)
No	60 (64.51%)	74 (58.73%)	38 (62.29%)	56 (58.33%)	22 (68.8%)	18 (60.00%)
I prefer not to answer	5 (5.39%)	11 (8.73%)	4 (6.57%)	6 (6.25%)	1 (3.1%)	5 (16.67%)
p-value	0.71	0.14
Q9. Are you aware of the current European Union legislation about plastic recycling?
Yes	20 (21.50%)	20 (15.87%)	14 (22.95%)	16 (16.67%)	6 (18.75%)	4 (13.33%)
No	71 (76.34%)	97 (76.98%)	45 (73.77%)	74 (77.08%)	26 (81.25%)	23 (76.67%)
I prefer not to answer	2 (2.16%)	9 (7.14%)	2 (3.28%)	6 (6.25%)	0	3 (10.00%)
p-value	0.50	0.74

). We performed 2-sided t-tests and assessed the presence of statistical significance at the 95% level.

Using gender as the dependent variable, most of the students described practicing recycling at home (men 79.41%, women 81.35%) (p = 0.16). In terms of voluntary participation in environmental protection, 55.88% of men and 59.32% of women students gave an affirmative answer. A 40.86% portion of both genders did not participate in any such activities (p = 0.41). The majority admitted to a lack of knowledge on the contents of a circular economy in dental practice (men 76.47%, women 62.71%) (p = 0.22). Similarly, most students (64.51%) did not know the EU’s legislation regarding the use of mercury (Hg) (men 61.76%, women 66.10%) (p = 0.57), nor the recycling of plastic (men 79.4%, women 74.6%) (p = 0.54). Accordingly, for the dentists, using gender as the dependent variable, it was reported that practicing dentists were not informed on the meaning of circular economy (men 65.22%, women 70.00%) (p = 0.24); nor were they informed on the EU regulations regarding mercury (men 58.69%, women 58.75%) (p = 0.36) or the recycling of plastic (men 76.09%, women 77.50%) (p = 0.54). It is important to note that no statistically significant correlations were reported according to gender (Table 2).

In Table 3, we present data from part B of the questionnaires according to the respondents’ place of origin/location of dentistry practice. No statistically significant correlations were found here either.

In the analysis of dental students’ perceptions of factors related to green dental practice, there seems to be a statistical difference between male and female students’ perceptions with regards to the increased costs required to make the necessary changes in utility networks (services including electricity, natural gas, and water) (p = 0.02), the reduced environmental integrity of building contractors (p = 0.057, marginal statistical significance) and poor wastewater management systems (p = 0.01), with female students being more prone to answer positively as “very significant”. No significant relationships were observed for gender in the study sample of the practicing dentists regarding the level of significance of factors related to green dental practice. The practicing dentists were also asked to name the most environmentally damaging practice in a dental practice, with wasted energy (p = 0.024) and the use of unapproved disinfection products (p = 0.036) being the most important (

Table 4. Rating of the most significant factors in green dental practices from dental students and practicing dentists according to gender.

	Gender
Dental Students	Males N (%)	Females N (%)	p Value *
Increased costs in utility networks
Neutral	6 (17.6%)	20 (33.9%)	0.02
Extremely insignificant	5 (14.7%)	1 (1.7%)
Extremely significant	23 (67.6%)	38 (64.4%)
Lack of environmental awareness of manufacturers
Neutral	6 (17.6%)	2 (3.4%)	0.057
Extremely insignificant	0 (0.0%)	3 (5.1%)
Extremely significant	28 (82.4%)	54 (91.5%)
Poor wastewater management
Neutral	7 (20.6%)	2 (3.4%)	0.01
Extremely insignificant	0 (0.0%)	4 (6.8%)
Extremely significant	27 (79.4%)	53 (89.8%)
Dentists	Most environmentally damaging practice in a dental practice
	Males N (%)	Females N (%)	p-value
Wasted energy
No	28 (60.87%)	32 (40.00%)	0.024
Yes	18 (39.13%)	48 (60.00%)
Use of unapproved disinfection products
No	36 (78.26%)	48 (60.00%)	0.036
Yes	10 (21.74%)	32 (40.00%)

* χ² test.

).

In

Table 5. Rating of the most significant factors in green dental practices by dental students and practicing dentists by place of residence.

	Place of Residence
Students	Urban	Rural N (%)	p Value *
Lack of financial support
Neutral	4 (6.6%)	4 (12.5%)	0.02
Extremeley insignificant	0 (0.0%)	4 (12.5%)
Extremely significant	57 (93.4%)	24 (75.0%)
Low level of “green” design in buildings
Neutral	2 (3.3%)	4 (12.5%)	0.03
Extremely insignificant	0 (0.0%)	2 (6.3%)
Extremely significant	59 (96.7%)	26 (81.2%)
Reduced profits of green dental practice in the near future
Neutral	12 (19.7%)	14 (43.8%)	0.04
Extremely insignificant	11 (18.0%)	3 (9.4%)
Extremely significant	38 (62.3%)	15 (46.9%)
Negligible benefits for the reputation of the business by today’s standards
Neutral	15 (24.5%)	14 (43.8%)	0.02
Extremeley insignificant	2 (3.3%)	5 (15.6%)
Extremeley significant	44 (72.2%)	13 (40.6%)
Lack of continuous education and training seminars on green dentistry
Neutral	9 (14.8%)	4 (12.5%)	0.05
Extremely insignificant	0 (0.0%)	3 (9.4%)
Extremely significant	52 (85.2%)	25 (78.1%)
Dentists
	Urban N (%)	Rural N (%)	p-value
Increased costs in utility networks
Neutral	19 (19.8%)	11 (34.4%)	0.08
Extremely insignificant	12 (4.9%)	3 (12.5%)
Extremely significant	43 (70.5%)	65 (67.7%)

* χ² test.

, we present an analysis of the perceptions of dental students and practicing dentists using place of residence as the dependent variable. There seems to be a statistical difference in the group of dental students between residents in urban areas and residents of rural areas with regards to the level of importance of the “lack of state funding” (p = 0.02), the “low level of green design in buildings” (p = 0.03), the “low benefit for the reputation of the green dental practice by today’s standards” (p = 0.02) for those practicing in urban areas, and of the “reduced profit of a green dental practice in the immediate future” (p = 0.04) and the “lack of continuous education seminars on green dentistry” (p = 0.05) for those practicing in non-urban areas.

On the other hand, no statistically significant relationships were observed in the group of dentists regarding the level of significance of influencing factors by place of residence, with only a weak relationship for the “increased in costs for changes related to utility networks” (p = 0.08). However, although no statistically significance differences were found in the analysis, it is interesting to note the trends in the participants’ replies, particularly that significant proportions of the responding dentists declared several of these practices to be non-significant or neutral, namely, “lengthening the construction time of a green dental practice” (49.2%, p = 0.56), “increased necessary and mandatory space required” (46%, p = 0.31), “reduced benefit for the reputation of the business by today’s standards” (45.3%, p = 0.26), and “not visible financial benefit in the near future” (43.6%, p = 0.44). An interesting finding is the perception of 88 dentists (69.8%) regarding the significant “importance of lack of knowledge on green dentistry” (p = 0.66). In the question that asked dentists to identify the most environmentally damaging practices in a dental practice by place of residence, weak relationships were observed with “increased wasteful energy” (p = 0.12) and “waste of dental materials” (p = 0.19).

Figure 4 shows a combined diagram of the relationship between urbanism and gender with environmental attitudes and knowledge for the students and dentists in our study. The diagram was designed using the Vensim program (Vensim PLE 8.1.0, US Patent Application EP19910909851, 26 February 1991) and shows factors influencing environmental volunteering and knowledge and attitudes regarding the circular economy. This modeling language supports relationships shown with arrays. It also permits mapping between factors, as in our study [73].

Causal trees of the results for both groups included in the study (students and dentists) are presented in Figure 5.

The dental students in our study proposed changes to promote eco-friendly dentistry in the undergraduate course curriculum, with the addition of seminars, short courses, or essay assignments on pro-environmental attitudes and actions and on ways to efficiently run a sustainable dental practice. Of the students, 68% suggested that they should visit green dental practices while studying, to form a specific idea of how to embed the guidelines in real working dental environments. Furthermore, the courses can be optional rather than compulsory, preferably available across the five-year span of their studies, to enable participation across different stages of students’ educational paths. They noted the need for: “Better understanding of the importance of green dentistry and motivation”, “Raising awareness about the importance of organizing a greener dental practice, as well as how some “small” changes can have a big impact on the future of our planet”, “Something to inspire students initially to raise awareness and motivation. Perhaps a professor who is a competent speaker and is a good example will help students to first “get acquainted” with the issue and lead to an awakening and willingness to further be informed on the subject”, “Visit to green dental clinics to see how they work”, “More frequent and organized information”, “To implement the ecological dental clinic at university clinic level as well”, and “A step-by-step contact with green dentistry and its benefits may have been able to energize students”.

Proposals from students regarding the implementation of eco-friendly practices within dental practice included the use of biodegradable materials, the use of solar power or renewable resources to meet energy demands, reducing the amount of dental waste and increasing recycling, along with familiarization with the corresponding legal frameworks, state financial support, and financial incentives to create green dental practices.

The dentists involved in our study proposed seminars or short courses during undergraduate studies to increase the ecological awareness of future dentists, as well as online seminars for professionals. They were quite reluctant to undertake actions themselves when governmental support does not exist: “In general, I think it is highly hypocritical to talk about ‘green’ dentistry when those in charge of the world are destroying the environment in every way. It is not the dentists, the problem!” or “The state’s measures should not only be revenue-collecting, with waste management companies, where you simply pay a fixed fee and continue to throw infectious waste in the bin (!!!) or ”Measures should not be obligatory because with the current economic conditions in Greece it is not possible, I believe to correspond…”or “Not just our financial burden with various mandatory subscriptions and changes in the area, but the obligation of the state to actually recycle and actually manage waste”.

With regard to proposals for the future of green dentistry, the use of energy-saving practices, renewable energy sources, biodegradable dental materials, and guidelines on plastic recycling and waste management practices were mentioned: “Energy study of the dental setting and appliances in the dental practice, information leaflets for patient information, mandatory labelling of materials by dental companies for their ecological footprint and the amount of energy cost for their production”.

5. Discussion

In this cross-sectional study, dental students and practicing dentists participated and provided information on their knowledge and beliefs regarding sustainability in dentistry, helping us to identify barriers to and enablers of pro-environmental behaviors concerning green buildings for dental settings in Greece. Both students and dentists exhibited a lack of knowledge on the topics of the circular economy, EU regulations on mercury use, and the recycling of plastic in dental settings, with similar percentages. This contrasts with their professed use of recycling at home and their voluntary participation in environmental protection activities. This is possibly because recycling at home has long been established through relevant state and international campaigns [11,80]. This attitude is not carried through to the workplace, where a lack of time at the end of the working day prevents employees from acting accordingly [6,25]. Although the findings did not reach statistical significance, men seem to be more informed on environmental terms and legislation, while women participate more in voluntary actions. Gender differences in environmental attitudes are also discussed elsewhere, with women recently catching up with men in terms of volunteering and engaging in more altruistic voluntary activities [81]. Participation in voluntary work may be associated with individual and societal benefits. Elsewhere, factors such as one’s socioeconomic status, marital status, social network size, church attendance, and previous volunteer experiences [82] are positively associated with volunteering, while age, functional limitations, and transitions into parenthood are described as being inversely related to volunteering [83], possibly due to a lack of time and increased demands from the emerging roles. Furthermore, green volunteering is inversely related to mortality [84,85], depression [85,86,87], and functional limitations [86], and positively related to self-rated health in adults and children [87,88]. Thus, green volunteering should be further enhanced in our sample, among both students and dentists, to promote not only their social profiles but also their wellbeing.

Unfortunately, over 60% of the professional dentists who participated in our study lacked knowledge of environmental legislation. This is a high percentage that dental authorities should take into consideration when designing environmental policies. Six out of ten dentists in our study do not know the legislation for the disposal of dental amalgam, which corresponds to other relevant findings [79]. Seven out of ten dentists do not know about the circular economy in dentistry and eight out of ten ignore regulations on the recycling of plastic in the dental practice. Those individuals need certain ethical (based on the reinforcement of values and knowledge of the code of dental ethics) and economic motivations to strengthen their pro-environmental behaviors, finally transforming it into sustainable environmental behaviors. Of course, we must keep in mind that, as explained elsewhere, economic motivation alone [82,89] will not provide the desired results, since providing monetary incentives can activate a processing mode that is transactional. Money can produce mental constructs that are incompatible with sustainable behaviors, and monetary incentives can signal that money is the reason to engage in the target action.

Another interesting finding of our study is the perception from two out of five dentists that a lack of seminars and education on green dentistry has a neutral impact or is less important to them. When asked to propose educational policies on the matter, they suggested interventions for young dentists and not themselves. On the other hand, students were more sensitive in acquiring knowledge on these issues than practicing dentists; this is characteristic of their generation, as mentioned elsewhere [90,91]. From our data, we can determine that certain behaviors—those that have significant negative environmental impacts—should form part of future educational policies. Pro-environmental behavior and the culture of Greek dentists addressed here and mentioned elsewhere [79] need direct revitalization. A systematic review of 66 studies from the scientific literature showed that dentists are permanently working on reducing the environmental impact of dental practice throughout the world [92], but this is not the case in our study.

With regards to the most significant factors affecting green dental building sustainability, students mentioned the increased costs related to utility networks, the lack of environmental awareness of building contractors, and the poor wastewater management, as mentioned elsewhere [18,19], whereas dentists did not identify any significant factors when examined by gender. On the other hand, when examined according to respondents’ place of residence and future place of dental practice, students identified as significant the lack of financial support, the low level of green design in buildings, the reduced profits of the dental practice, the negligible reputational benefits, and the lack of continuous education seminars on green dentistry. These responses correspond to a specific sensitivity on the matter, as discussed elsewhere [90,92,93,94].

Worldwide and in Greece, the green building market share is still very small due to the extra costs it involves. This cost is attributed to materials, design, and technological issues [21,22,23,24]. Despite the numerous benefits associated with green constructions, the issue of extra costs is a frequently cited obstacle for buyers of green buildings [22,23,24,95]. The costs of green buildings have risen from 1.84% higher on average a decade ago [26] to almost 20% in more recent studies [27,28,29]. In the green building movement, more than half of the construction costs are related to green features such as alternative systems, software for smart applications, and materials. Aside from the construction costs, there are also soft costs, including certification applications, approval, consultancy, and additional design costs. The extra costs significantly hamper the large-scale adoption of green buildings [96,97], even though they provide credits on the green building rating system [28,29]. Our data also support this finding.

Economic factors concerning the implementation of green construction and the function of dental practices, low motivation, and the consequences of the pandemic on sustainability issues [98] could explain the low response rate in our study and the non-significant values for most of the factors related to green dental constructions, both according to gender and urbanism. It is a fact that, after the COVID-19 pandemic, dentistry became more expensive and professionals seem reluctant to shoulder another increase in the cost of practicing dentistry, which will include construction or energy changes [98,99]. Urbanism seems to play an important role for students and a weak but not statistically important one for professional dentists as far as it concerns environmental philosophy and its economic consequences. The findings can be explained by the fact that practicing dentistry in urban areas seems to be more expensive and demanding due to the costs of transportation, trafficking [18,19,20], and bigger dental practices reported in our data and noted elsewhere [6,25]. For dentists in urban areas, the waste of dental materials is the most salient matter since they seem to practice more expensive dentistry, and this factor has economic consequences that reduce their income [25].

Overall, the factors determining pro-environmental behavior in our study are gender, urbanism, perceptions of costs and benefits, habits based on a lack of information, time management, participants’ economic status, and ethics, as discussed elsewhere [100]. Interventions that could best be applied to encourage pro-environmental behaviors are informational strategies (information, persuasion, social support and role models, and public participation in voluntary actions designed by dental or health state authorities) and structural strategies (availability of products and services, lowering the cost of recycling cleaning products, legal regulation, and financial strategies) [14]. The expected effects of such interventions are changes in behavioral determinants, changes in behaviors (purchasing, using, refilling), changes in environmental quality, and changes in individuals’ quality of life (changing purchasing behaviors generally has greater environmental benefits than reusing or recycling available products) [93,94]. As we propose designing effective interventions to modify habitual pro-environmental behaviors, it is important to consider how habits are formed, reinforced, and sustained [96,97,100,101,102]. Dental authorities and energy companies should therefore play an important role in rewarding green practices and cultivating green impulses among professionals to change habits and improve motivations, perceptions, cognitions, and norms. Meanwhile, structural state strategies should focus on changing the circumstances under which behavioral choices are made [14,47,48,91].

We can derive both theoretical and practical implications from our data. These data help to highlight some of the issues that are considered important by a sample of practicing dentists and dental students, and which indicate a lack of knowledge (e.g., circular economy, EU legislation on mercury) or inform environmental behaviors (e.g., poor waste management, use of non-approved disinfection products) and factors affecting their GDB choices. Our findings also point to some practices that are deemed important for the establishment of green dentistry (e.g., seminars, green building design parameters, enhancing environmental volunteering) and the design and function of a professional practice that is linked to environmental awareness and sustainability.

6. Conclusions

The analysis according to place of residence and place of dental practice indicates some functional obstacles in the establishment of environmental sustainability, such as the lack of financial support, the low level of green design in buildings, and increased costs for utility networks, which are obviously linked to difficulties in sustainable urban design regulations and limited financial support for creating an eco-friendly practice. Dental students seem to be more engaged in identifying ways to increase access to new information on environmentally sustainable dentistry and green buildings that host modern dental practices, and more committed to improving their eco-employment prospects. Practicing dentists, on the other hand, seem more set in their ways; they appear less engaged with the prospect of switching to environmentally sustainable practices in dentistry and less interested in participating in continuous educational activities compared to students. Introducing the topic of environmentally sustainable dentistry (ESD) in the undergraduate dental course curriculum is vital to providing the necessary knowledge to new generations of dentists and to enabling the implementation of a series of sustainable practices in dentistry by choice and not merely due to the need to adhere to guidelines and regulations. The corresponding changes in policies and regulations when setting up a dental practice need to meet environmentally sustainable requirements along with regularly updated guidance on changes and new developments in the field. Facilitators such as funding opportunities and user-friendly administrative procedures will favor the shift to establishing more green dental practices in the future. Although green dentistry is an interesting marketing tool for all health professionals in the public and private sectors, there is a need for additional guidelines, tools, techniques, and state support to share common environmental ethics and practices.

This study has certain limitations. The data regarding factors influencing the acceptance of the cost of green dental buildings were mainly based on factors mentioned in other studies [4,5,14,15,34,61,65,66,67,68,71,72] and not on specific factors that exist in the building construction industry in Greece. Because of this limitation, the behavioral results should be further assessed to link specific green building elements with the environmental issues addressed in this study. There is also a lack of experimental elements which could more rigorously assess the willingness and practices of the specific sample, as reported elsewhere [79,95,103]. Moreover, a larger sample could have provided us with more robust results for the observed associations, which, in turn, could provide the basis for formulating proposals for stakeholders and a better assessment of their values. The low response rate to the survey precludes the generalization of the findings and the cross-sectional design only presents a static image of attitudes towards green dentistry issues in Greece during a certain period. However, the low participation rate may also indicate some degree of selection bias, in that those who are most interested in green dentistry practices responded to the questionnaires. In this case, the observed findings may be overestimated, which means that the true relationships in the total population of practicing dentists and dental students are much weaker and more efforts are required to establish green dental practices. Finally, the survey was conducted among a population of dentists and students in one country (Greece) and the findings need to be verified in other settings to formulate specific policies and legislation with a greater reach.

Despite these limitations, it is obvious that there is a need for more evidence to inform the green health building movement in Greece. A future study should apply different psychological, social, or economic theories to investigate students’ and dentists’ willingness to adopt sustainable pro-environmental behaviors. We should further investigate the values that reinforce environmental actions. Finally, additional study of the issue should address different motivators and facilitators of behavioral changes after specifically designed educational interventions. In this regard, the questionnaires used in this study could be used in the future to assess a larger sample of respondents from across the whole country. An assessment baseline level of the target behaviors should be further examined in this future sample after information sharing through social media and continuing educational projects from universities and dental associations. Dental associations must accordingly assess the long-term feasibility of changing the behaviors of their members after implementing the relevant educational campaigns. The reluctance of dentists to participate in this eco-study reflects their negative attitude towards actions that will possibly incur unexpected or obligatory costs. This attitude could be possibly overcome by a reward for participation, as mentioned elsewhere [104]. It is also necessary to determine the respondents’ spending power and the availability of resources for green materials and buildings.