Background: Children with Autism Spectrum Disorder (ASD) frequently exhibit sensory hypersensitivity, anxiety, and behavioral challenges that complicate dental treatment. Acceptance of the nasal hood is essential for successful nitrous oxide–oxygen inhalation sedation; however, tactile and olfactory sensitivities may contribute to resistance during hood placement. Sensory-adapted interventions such as guided familiarization and preferred scented nasal hoods may improve sedation acceptance and behavioral cooperation in children with ASD.

Aim: To evaluate the effect of preferred scented nasal hoods on acceptance of nitrous oxide–oxygen inhalation sedation in children with Autism Spectrum Disorder and to assess the role of sensory processing profiles in influencing behavioral cooperation during dental treatment.

Materials and Methods: A prospective randomized clinical trial was conducted among 60 children aged 4–12 years diagnosed with Autism Spectrum Disorder level-1 requiring dental treatment under nitrous oxide–oxygen inhalation sedation. Participants were randomly allocated into two groups: preferred scented nasal hood group (n = 30) and non-scented nasal hood group (n = 30). Prior to treatment, parents completed a modified Short Sensory Profile questionnaire assessing tactile, olfactory, auditory, and environmental sensory sensitivities. Guided familiarization using tell-show-do and gradual exposure techniques was performed before nasal hood placement. In the scented group, preferred scents were selected based on parental interview and sensory preference assessment. Primary outcome assessment included nasal hood acceptance, while secondary outcomes included Frankl behavior rating scores, hood placement time, sensory sensitivity correlation, and requirement for additional behavior guidance.

Results: Successful nasal hood acceptance was significantly greater in the preferred scented nasal hood group compared with the non-scented nasal hood group (93.3% vs. 73.3%; p = 0.028). Mean hood placement time was significantly shorter in the scented group (38.6 ± 11.4 seconds) than in the non-scented group (65.2 ± 17.8 seconds) (p < 0.001). Positive Frankl behavior ratings were observed more frequently in the scented group (86.7%) compared with the non-scented group (60.0%) (p = 0.019). Higher tactile and olfactory sensitivity scores demonstrated significant negative correlation with nasal hood acceptance.

Conclusion: Preferred scented nasal hoods combined with guided familiarization significantly improved inhalation sedation acceptance and behavioral cooperation among children with Autism Spectrum Disorder. Sensory-adapted approaches based on individual sensory profiles may provide an effective and clinically practical strategy for enhancing behavior guidance during pediatric dental treatment.