Evaluation of pediatric drugs on the surface roughness of primary enamel and restorative materials: an in vitro study

BACKGROUND: Pediatric liquid medications may adversely affect the surface properties of dental tissues and restorative materials. This study assessed the effect of amoxicillin and azithromycin suspensions on the surface roughness of primary enamel, Cention N, and resin-modified glass ionomer (RMGI). METHODS: A total of 90 specimens were included in this study: 30 primary enamel specimens, 30 Cention N specimens, and 30 RMGI specimens. Each substrate group was further subdivided into three subgroups (n = 10) according to the immersion medium: amoxicillin suspension, azithromycin suspension, or artificial saliva. Surface roughness (Ra) was measured using a contact profilometer at baseline and after completion of three consecutive 7-day immersion cycles separated by 2-day intervals. The cumulative exposure times were 126 min for amoxicillin and 42 min for azithromycin. Data were analyzed using IBM SPSS software. Normality was assessed using the Shapiro-Wilk test, and statistical analysis was performed using paired t-test, one-way ANOVA, and two-way ANOVA, with the level of significance set at p ≤ 0.05. RESULTS: Both amoxicillin and azithromycin suspensions significantly increased surface roughness compared with artificial saliva (p < 0.001 and p = 0.001, respectively), with no significant difference between the two antibiotics (p = 0.999). In all material groups, both suspensions significantly increased surface roughness, whereas artificial saliva caused no significant change. Primary enamel showed a significantly lower increase in surface roughness than both Cention N and RMGI. CONCLUSIONS: Both amoxicillin and azithromycin pediatric suspensions increased the surface roughness of primary enamel, Cention N, and RMGI under the conditions of this in vitro study. Although azithromycin showed an alkaline pH, the comparable roughening effects of the two antibiotics suggest that surface changes may be influenced by multiple factors, including formulation characteristics and cumulative exposure time.