Frequency of four-dimensional oral health problems across dental fields – A comparative survey of Slovenian and international dentists

At least 13 different oral health models exist (1, 2), providing dentists and researchers a theoretical framework with the most comprehensible explanation of the oral health-related quality of life (OHRQoL) (3) concept. An empirically derived oral health model defined by Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact dimensions was introduced in 2014 (4, 5). These four dimensions were found to be valid based on exploratory and confirmatory factor analysis (4, 5, 6) using dental patient-reported outcome measure (dPROM) data (7) via the 49-item Oral Health Impact Profile (OHIP-49) (8) obtained from more than 10,000 dental patients and general-population subjects from six countries. While the original authors assumed the four dimensions to be universal for oral health, this assumption has not been tested across dental fields. Various dental fields are recognized under dentistry, and they are all essential to provide the best treatment for a specific disease-oriented orofacial condition. Although dental fields are defined and named differently in various countries, they all share the same purpose, namely to restore and improve patients’ functional, pain-related, aesthetic, and psychosocial disorders related to their entire orofacial system, which in turn improves their quality of life. Therefore, by practicing various dental fields, it is possible to assess the four OHRQoL dimensions in patient care, public health, research, and education.

Most dentists work with patients daily and are aware of why their patients seek oral health care, i.e. due to functional, pain-related, aesthetic, and psychosocial problems associated with their oral health concerns (9, 10). Patients also visit dentists to prevent possible problems (11). As a result, dentists try to eliminate or alleviate patients’ orofacial pain, restore or improve their function, improve orofacial aesthetics, and help patients with their psychosocial concerns, e.g. increase their possible low self-esteem by applying aesthetic restorative dental treatments or by counseling about halitosis and tooth discoloration (12). In essence, the dentist’s role is to diagnose oral diseases, promote oral health and disease prevention, develop treatment plans to maintain or restore patients’ oral health, interpret x-rays and diagnostic tests, ensure the safe administration of anesthetics, monitor the growth and development of the teeth and jaws, perform surgical procedures, and improve patients’ OHRQoL (13, 14).

So far, only a few studies have evaluated patients’ problems based on dental professionals’ perspectives. Authors have utilized electronic surveys to assess patient-specific factors related to oral health based on international health professionals’ estimation grouped into six world regions defined by the World Health Organization (WHO) (15, 16, 17). A study by Dougall et al. (16) used the online Global Oral Health Survey to explore functioning, participation, social environment, and other factors concerning oral health based on the International Classification of Functioning, Disability, and Health (ICF) (18). Similarly, Faulks et al. (15) applied the ICF version for children and young people, an online Delphi survey, to investigate children’s oral health from health practitioners’ viewpoint. Research has not yet been conducted on evaluating patients’ oral health problems and prevention needs, based on dentists’ surveyed opinion, coinciding with the four OHRQoL dimensions within dental fields across countries belonging to all six WHO regions.

Because Slovenia is a relatively small country in the European Region with good oral health and the possibility of prompt dental care, we wanted to review patients’ functional, pain-related, aesthetic, and psychosocial problems and prevention needs obtained through the opinion of dentists engaged in six clinical dental fields and compare them with international patients’ oral health problems and prevention needs.

Thus, this study’s objective was to compare the frequency of patients’ oral health problems and prevention needs as reported by Slovenian and international dentists with the aim to validate the four OHRQoL dimensions across six clinical dental fields in all WHO regions.

This study encompassed responses from 223 Slovenian and 1,357 international dentists who provided information on approximately more than 15,800 patients. All six dental fields showed comparable classification of patients’ problems and prevention needs, based on dentists’ surveyed opinion, regardless of the country and the WHO region. Patients’ pain-related problems and prevention needs were the most common reasons for visiting dentists in all WHO regions, as reported by dentists. Regardless of cultural and sampling differences between Slovenian and international dentists, the distribution of dental patients’ oral health problems and prevention needs, based on the dentists’ surveyed opinion, into the four OHRQoL dimensions is comparable.

Our study shares some similarities in methodological approach with previous research (15, 16) as we followed the WHO’s regional classification and used international dentists’ evaluation. However, their study participants were not only dentists but also other health professionals. Both studies reported more than 80% of a holistic aspect of oral health within a group of international professionals when considering ICF items’ importance and other factors related to their studies (15, 16). Similarly, our results showed that international dentists comprehensively classified more than 90% of patients’ problems and prevention needs into the four dimensions regardless of dental field and the country of origin.

Similarly, for sleep medicine, a research group (21) conducted an online survey of international health professionals’ evaluation of patient-specific problems related to sleep disorders applying the ICF. In comparison, our online survey consisted of four main questions with offered answers in percentages or numbers. Moreover, we considered cultural and sampling differences while evaluating international dentists’ responses. Dentists’ clinical assessment of patients’ oral health concerns is essential because it provides accurate data and reliable results (22). Such results make it possible to categorize patients’ oral health problems and prevention needs for each dental field into four dimensions. Providing evidence that the four OHRQoL dimensions are a robust framework applicable for patient care, teaching, and research across all dental fields would accelerate its acceptance, promotion, and use worldwide.

Other studies used experts’ opinions to create dPROMs by grouping dental patients’ oral health problems into seven domains: Functional Limitation, Physical disability, Psychological discomfort, Physical disability, Psychological disability, Social disability, and Handicap (23), providing validity for OHIP-49 dPROM. Using experts to assign items to attributes, this approach was also applied in a recent systematic review identifying generic dPROMs where authors relied on their clinical expertise for item assignment (7). Although similar methods were used, none of those studies were done using the WHO’s country classification by world regions (17) and clinically testing the four oral health dimensions.

Thirty-two countries and at least three countries per WHO region were included. The three most numerous and seven largest countries also participated in this study. Using the electronic survey, we included many dentists from all around the world, obtaining a large sample size. Collecting de-identified data, we ensured confidentiality and unbiased results. This strategy helped increase the credibility of our research results and the response rate. Nevertheless, we were unable to determine dentists’ response rates, as their answers were unidentified. If a particular dentist was approached by the center dentist, we did not know whether he or she participated in the study, i.e. center dentists may have invited 30 people to perform the survey, but only 10 of them completed it. If participation were related to the frequency of patients’ problems and prevention needs, our results would be biased. However, we believe this situation is not probable since we did not find any cause, i.e. demographic characteristics, as factors for functional, pain-related, aesthetic, and psychosocial oral health concerns related to the frequency of international patients’ problems and prevention needs.

This study has some limitations, such as different sampling methods between Slovenia and other participating countries. Slovenian data had a different data collection methodology because we could invite all active dentists, due to the small population size, without influencing the four-dimensional problems. We could have calculated proportions, ES, and 95% CI for dentists’ assessments that work in only one dental field, providing a complementary perspective. Due to different sampling methodologies and the insufficient number of dentists working in just one dental field, we omit such computations. The findings would result in being unstable just because of chance since the number of dentists was too low to be analyzed. We would have been left with problems in interpreting results as accurate or just caused by chance. We could have presented separate results for each WHO region. However, because of zero to small differences between dentists’ evaluation from Slovenian, European Region, and 31 countries across dental fields, the results reporting findings for each WHO region would have been repeated. Except for Slovenia, we used a convenience sampling of international dentists due to a lack of performing a probability sampling. Despite the different sampling strategies between Slovenia and 31 countries, results did not influence the categorization of the four-dimensional problems and prevention needs within dental fields. However, due to other countries’ convenience sampling, any of these could have been over- or sub-represented. Our goal was to target individual dental specialties. However, some difficulties arose in listing them all since specific specialties differ between countries in terms of name and number of recognized specialties by dental organizations in the 32 participating countries. Thus, we decided to use dental fields that cover all or most specialties performed internationally. Even though we encompassed only six dental fields, which could have been an essential factor that challenges the four dimensions’ usefulness, the six spheres contained all relevant dental specialties, regardless of the country and the WHO region that dentists came from. Therefore, each participating dentist could have selected one or more of the proposed dental fields of interest.

Dental fields are known to have their specific purposes. For instance, prosthodontics (24, 25) covers the dimension of Oral Function primarily with the goal to restore patients’ capacity to chew; orthodontics (26) targets mainly Orofacial Appearance where its predominant outcomes are physical diseases; TMD (27) has Orofacial Pain as a primary target, as it consists primarily of temporary or long-lasting severe pain and discomfort in the orofacial region. While physical disease measurement is different, impact measurement utilizing the four-dimensional set is the same. Likewise, the four OHRQoL dimensions’ sum is always 100%, despite the different dimensional distribution. With this approach, a structure measuring a particular dental field’s target by applying the four OHRQoL dimensions was presented.

Slovenian and international dentists from six major dental fields have classified more than 90% of their patients’ oral health problems and prevention needs into the four OHRQoL dimensions. Thus, according to the dentists surveyed, the frequency of patients’ oral health problems and prevention needs is comparable between Slovenia and 31 countries, regionally and globally. Dental patients’ functional, pain-related, aesthetic, and psychosocial problems and prevention needs can be considered universal across all dental fields, providing a global basis for the application of evidence-based dentistry (28, 29) and core content of provider-doctors’ and patients’ communication (30), as well as paving the way towards value-based oral health care (31).