The main results of this study indicate associations between PSOLs and aspects related to the sexual behavior of young people, suggesting that some behavioral patterns with a higher risk for the development of STI are also related to the presence of PSOLs. The identification of this relationship, which has not yet been addressed in the literature, is a helpful alert to health professionals involved in the care of young people for the prevention and early diagnosis of STI. Besides, this can be an indication that dental consultations represent a valuable opportunity for a comprehensive approach to these individuals with an emphasis on aspects related to their sexual and reproductive health.
The relationship between oral health and sexual and reproductive health is recognized in the literature, which focuses on the characterization of oral lesions resulting from already established STI and their role as markers for the diagnosis or progression of these infections. The most illustrative examples of this relationship are the oral manifestations of AIDS, such as oral candidiasis, oral hairy leukoplakia and periodontal disease [19, 23, 24], and oral lesions caused by acquired syphilis [1, 20, 25]. The oral manifestations related to these disorders may even be the first symptoms of infection or disease progression, which reinforces the importance of their identification during dental consultations [18].
In the present study, patients with self-reported or diagnosed STI significantly more frequently reported having PSOLs according to both the results of the simple analysis (Table 4) and the results of the model adjusted for sex, social class, and education level (Fig. 1). Given that the etiologies of the self-reported lesions were not known, the association found is susceptible to different interpretations. This relationship may reflect a pattern of neglect towards health-related self-care (or lack of access to such care) as oral lesions may be due to, for example, dental infections. A second interpretation is the existence of a clinical relationship between the presence of STI and oral lesions, which would be compatible with the stratification results in the adjusted model (Fig. 1): The association between an HIV or syphilis diagnosis or a self-reported STI and PSOLs lost significance among individuals who did not practice oral sex but persisted among those who practiced oral sex, which increases the oral inoculation of sexually transmitted pathogens [26]. Regardless of the interpretation, self-reports of PSOLs may serve as strategic information to assist in the early diagnosis of STI.
With the identification of the growing role of HPV in the etiology of head and neck cancer, aspects of the sexual behavior of patients began to be investigated [27]. Greater numbers of sexual partners and oral sex partners seem to be associated with an increased risk of developing head and neck cancer (OR = 1.29, 95% CI = 1.02 to 1.63 and OR = 1.69, 95% CI = 1.00 to 2.84, respectively) [9]. Notably, specifically in oral cancer, the association with exposure variables of this nature has not been demonstrated [28]. The establishment of this relationship introduced a new responsibility to professionals in the field of head and neck cancer involving counseling regarding sexual behavior rather than only traditional risk factors such as smoking and alcohol consumption [27]. However, the approach of the oral health and sexual behavior interface towards prevention remains minimally explored.
In the analysis adjusted for sex, social class, and education level in this study (Table 5), not using condoms as a contraceptive method and having intercourse with 2 or more partners in the past year were identified as behaviors significantly associated with a higher prevalence of PSOLs. Both behaviors are considered risky practices for the development of STI [29] and had high sample frequencies (49.29% and 32.99%, respectively). Given these results, information on the presence of PSOLs obtained during dental consultations with adolescent and young adult patients or from collective approaches in the general population can be powerful to facilitate a dialog regarding safe sex practices and STI prevention, early diagnosis of related conditions, and the provision of comprehensive and multidisciplinary care to these individuals.
The adolescent patient health approach should consider the peculiarities of this life stage. At this stage, neurophysiological maturation is still incomplete, and the ability to understand the relationship between behavior and consequences is not fully developed. These individuals are often exposed to some pressure towards experimentation, which includes drug use and early sexual contact [30]. In addition, adolescents and young adults usually seek health services for acute and specific complaints and not for health counseling and/or reviews [31, 32] and are concerned with confidentiality regarding their relationship with the health service [33]. This population (15 to 24 years old) bears the greatest STI burden among all age groups, accounting for half of the 20 million new cases diagnosed annually in the USA [34]. Thus, general dentists and dental hygienists are often the only health professionals involved in this scenario. A study of 743 adolescents in Southern Brazil indicated that “health problems” were the main reason (69.0%) for them to seek health care in the last month. When researchers detailed these problems, they identified oral health as the second most frequent complaint, second only to respiratory issues [31]. The latest National Survey of Oral Health in Brazil indicated that 85.8% of adolescents aged 15 to 19 consulted a dentist at some time in their lives, and 53.9% of these consulted less than 1 year ago—despite regional discrepancies, these totals were never less than 79.8% and 50%, respectively [35]. The results in the 2013 National Health Survey of Brazil (PNS) indicated similar percentages as follows: 51% of young people aged 18 to 29 years visited a dentist in the last 12 months [36].
The willingness of oral health teams to address sexual health issues is a topic that requires attention. The technical-centered profile of dentistry, aggravated by the fact that sexual health is a sensitive question, can result in the underutilization of dental consultation, which could be an opportunity for comprehensive care for youths. A study carried out with 929 dentists from Florida/USA indicated that these professionals express less intention to advise adolescents about HPV—compared with counseling on sugar consumption—mainly due to the perception that this is less socially acceptable conduct [37]. In another study, dental providers—dentists and dental hygienists—reported the lack of ability to conduct this type of conversation as a barrier to acting in the education for HPV prevention; they also related concerns about the reaction of patients (or their parents) and the scarcity of time and privacy in the care spaces [38]. However, dentists are the professionals who most know about changes in the oral mucosa and the dental hygienists can be considered as “prevention experts.” Due to these privileged and opportune positions for counseling, further training on the topic and development of health literacy skills can be alternatives for the engagement of dental providers in prevention related to STI [39].
Moreover, coping with STI is a relevant issue in Brazil, and statistics reflecting, for example, the increased number of cases of acquired syphilis, syphilis in pregnant women, and congenital syphilis have been highlighted in the last decade. From 2016 to 2017, increases of 31.8% in the incidence of acquired syphilis, 28.5% in the syphilis detection rate among pregnant women, and 16.4% in the incidence rate of acquired syphilis (rates of 58.1, 17.2, and 8.8 cases per 100,000 inhabitants in 2017, respectively) were documented [40]. In addition, from 2014 to 2018, only 20.1% of boys aged 11 to 14 years were vaccinated against the HPV virus, although the target for the country was 80% [41]. The subtypes of this virus classified as high risk due to their roles as etiological factors of cervical, oropharyngeal, and penile cancer [4] were present in 35.19% of the sample.
The main limitation of the present study was the self-reported format of the outcome variable and some exposure variables, which did not promote the reliability of the information or clarification of the etiologies of the PSOLs. A study carried out in Southern Brazil, in which 720 young adults from a birth cohort were examined, identified papules/nodules as the most frequent alteration of the oral mucosa (32% of individuals with lesion), followed by ulcers (26.5%); the most affected location was gingiva (35%), followed by lips (21%) [42]. A 10-year review of biopsy results in oral lesions of children and adolescents found mucocele as the most common diagnosis (33.3%) [43]. As we have not found studies that validate the self-report of oral lesions, discussing the etiology of the PSOLs in this study is not very conceptual. However, we understand that there may be a consistent presence of lesions due to recurrent aphthous ulcerations, mucocele, and recurrent herpes labialis, based on the age of individuals and most common anatomical locations (Table 4) [42,43,44].
We emphasize that, despite being a significant limitation, self-reported oral health status is an outcome often used in population-based surveys and in studies with large samples [45], the validity of which has been demonstrated mainly in studies analyzing the periodontal conditions of individuals [46]. This strategy enables the collection of health information in unfavorable contexts for individual tests and determination of a patient’s history and not only his/her condition at a given time [44].
We found associations between PSOLs and aspects related to the sexual behavior of adolescents and young adults; some behavioral patterns—with a higher risk for the development of STI—and history or diagnosis of STI are related to the presence of PSOLs. Our results instigate some final reflections: Despite seeking to raise awareness for objectives different from those presented in the literature, such as screening for oral cancer, the results suggest the prior knowledge that mucosal examinations should be a routine practice in dental consultations. Notably, a dental anamnesis addressing oral lesion history can also be a powerful tool for the care of adolescents and young adults, allowing extension beyond the dental approach. In addition to oral diagnoses, oral health teams should be able to address issues related to the diagnosis of STI and safe sex practices, which is a critical issue mainly for young individuals who rarely attend health services and whose only link with health services is the oral health team. The reverse perspective must also be considered: All health professionals involved in the care of these patients should be aware of opportunities for oral health care, especially symptoms and signs of oral mucosal changes. The results found in the present study are powerful for promoting a more integrated, vigilant, and diligent approach to sexual and reproductive health and its interface with oral health.