Interactive Versus Observer-Only Virtual Reality for Pediatric Mandibular Posterior Tooth Extraction: An Analyst-Masked Split-Mouth Crossover Trial

Abstract

Background: Virtual reality (VR) is increasingly used as a nonpharmacological distraction method during pediatric dental care. However, it remains unclear whether a child-directed interactive VR game provides a meaningful advantage over an observer-only immersive display during tooth extraction. Objectives: This study compared interactive with observer-only VR during mandibular posterior primary-tooth extraction in children aged 8 - 10 years. Outcomes included child-reported dental fear/anxiety, observed behavior, heart rate, and parent satisfaction. Methods: An analyst-masked split-mouth crossover clinical trial was conducted at Zahedan Dental School, Iran. Forty-eight children requiring bilateral mandibular posterior primary-tooth extraction were allocated sequentially to 2 intervention sequences and attended 2 treatment visits 1 week apart. In Sequence Group I, children received observer-only VR at the first visit and interactive VR at the second visit; in Sequence Group II, they received the interventions in the reverse order. Because the VR formats were visibly different, the children, parents or legal guardians, the operator, the in-session scorer, and the video reviewer were not masked. Intervention labels were coded during data preparation and statistical analysis. The primary endpoint was post-extraction dental fear/anxiety, assessed using the Facial Image Scale (FIS). Secondary outcomes were the reverse-scored Frankl Behaviour Rating Scale (FBRS), heart rate (HR), and parent satisfaction. SPSS 26.0 was used for descriptive, paired, and repeated-measures procedures; R was used for mixed-effects models adjusted for baseline score, period, and sequence. Results: All 48 enrolled children completed both visits. HR, FIS, and reverse-scored FBRS changed across procedural stages. The treatment-by-time interaction was not significant for HR or FIS but was significant for FBRS. In baseline-adjusted mixed-effects models, observer-only VR was associated with lower reverse-scored FBRS after injection (beta = -0.27; 95% CI, -0.51 to -0.03; P = 0.025) and after extraction (beta = -0.29; 95% CI, -0.53 to -0.05; P = 0.017). Adjusted HR and the primary FIS comparison were not statistically significant. Parent satisfaction was similar between interactive and observer-only VR (7.48 ± 1.96 vs 7.56 ± 1.83; P = 0.699). No participant withdrew, no treatment session was interrupted, and no serious tolerability issues were recorded. Conclusions: In this single-center crossover trial, interactive VR was not superior to observer-only VR for cooperative children aged 8 - 10 years undergoing mandibular posterior extraction. Observer-only immersion may be more suitable for short, invasive pediatric dental visits. These findings should be interpreted cautiously because sequence allocation followed a predictable, one-by-one pattern.