[Evaluation of the timing of orthodontic arch expansion and graft in cleft lip and palate].

Maxillary transverse growth is inhibited by congenital cleft, early surgical scar strain, and oppression of lipmuscles in patients with cleft lip and palate. Clinical manifestations have shown severely constricted maxilla, insufficientmaxillary width, mismatch of upper and lower dental arches, and crossbite. Alveolar bone graft and arch expansion can effectively correct the deficiency in maxillary width. This paper discusses the timing and success rate of alveolar bone graft, as wellas the relationship between alveolar bone graft and arch expansion. Secondary alveolar bone graft is optimally performed beforepermanent canine eruption, especially when the teeth have formed between half and three quarters of their roots. Rapid maxillaryexpansion prior to alveolar bone graft is beneficial because this process increases the gap of the cleft, expands bone graft, andreduces the difficulty. However, the stability of this process remains controversial. Small-scale studies have reported that rapidmaxillary expansion after alveolar bone graft can open the midpalatal suture without bone graft loss. Slow maxillary expansioncan provide continuous light forces to reconstruct the bone. However, these studies are coordinated with fixed orthodontictreatment. Further research is necessary to determine the effects of maxillary expansion on long-term stability of teeth.