To assess the effectiveness of a psychoeducational intervention program designed to facilitate the performance of a series of steps of oral examination in children, adolescents and adults with autism spectrum disorder (ASD), in the Bio-Bio region, Chile. Material and Methods: A prospective, quasi-experimental study with pre-intervention, post-intervention and maintenance tests was carried out. Behavior was measured using Frankl's scale and the number of steps of a dental examination completed

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... -10 steps) was also recorded. Only 104 of the 188 subjects with ASD that agreed to participate in the study met all the inclusion criteria. Results: 82 people with ASD completed the psychoeducational intervention. The mean number of steps achieved pre-and post-intervention was 4.1 and 9.4, resulting in a clinically and statistically significant difference. Regarding behavior, the median in the pre-test was 2 (negative behavior) and in the post-test it increased to 3 (positive behavior), this difference being relevant and statistically significant. A maintenance test one month later on 63 people with ASD found no variations in behavior and in the number of examination steps completed. Conclusions: The proposed intervention was effective as an increase of more than 5 in the number of steps of examination completed was achieved. Frankl's behavior rating also increased, from negative to positive, in a group of children, adolescents and adults with ASD.