Status of first molars, its visualization in a smile and opinion about its influence on an esthetics teeth arch: comparative study of Russian and foreign students

AIM. To determine factors influencing the assessment of the contribution of the first molar to smile aesthetics in Russian and international students.

MATERIALS AND METHODS. The study involved 193 students, including 119 Russian citizens (21.63 ± 1.55 years old) and 74 international students (23.93 ± 2.82 years old). Participants completed an anonymous questionnaire and then underwent a clinical oral examination, during which the condition of their first molars was assessed for caries, fillings, and artificial crowns, as well as the visibility of the first molars during a broad smile and loud laughter. Statistical analysis was performed using StatTech v. 4.9.2, values at p < 0.05 were considered significant.

RESULTS. Among Russian students, 1 (0.8%) had amalgam fillings in the area of their first molars, compared to 22 (29.7%) among foreign students, predominantly students from Iran (24.3%); the difference was significant (p < 0.001). Chinese students were more likely to have intact first molars (75%). Upper and lower molars were visible in the smile zone in 47.1% and 54.1% of participants, respectively, with no significant difference between the groups. Russian students were more likely to pay attention to the condition of their first molars (66.4% vs. 44.6%; p = 0.002), while foreign students were more likely to rate the contribution of molars to aesthetics as “significant” (48.6% vs. 29.4%; p < 0.001). Women were more likely to note the aesthetic significance of first molars (p = 0.032).

CONCLUSIONS. The condition and visibility of first molars influence the perception of smile aesthetics. Cross-cultural differences in the prevalence of amalgam restorations and the assessment of the aesthetic significance of first molars highlight the need to consider national dental traditions and gender differences when analyzing factors shaping smile perception. Among Russian students, dental factors influence the assessment of the contribution of first molars to smile aesthetics. Among foreign students, gender, along with dental factors, has a significant influence.

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