My son mouth breaths so we've been working on daytime nose breathing. his mild osa has improved since, should we keep doing this?

Behavioral methods : Used by speech/language & occupational therapists help kids with low oral motor tone & persistent drooling ( > 18 mos. Developmental age) learn to maintain a closed-mouth posture, even with intellectual disability from genetic or other medical causes. Malformations of oral structures, chin & nose & chronic vasomotor or allergic rhinitis hamper progress.A pediatric dentist & ENT can assess.