RESUMO
Objective@#To explore how to select osteotomy line and its significance in mandibular distraction osteogenesis in infants and young children.@*Methods@#From May 2013 to July 2018, 208 infants and young children with mandibular deformity were admitted to the Department of Oral and Maxillofacial Surgery, Guangzhou Women and Children Medical Center, including 131 males and 77 females, with the age range of 8 days to 4 years, mean age of 6 months. Their clinical records were retrospectively analyzed. There were 162 cases of Robin sequence, 37 cases of the first and branchial arch anomalies, 2 cases of Treacher-Collins syndrome, and 7 cases of other congenital malformations. During the distraction osteogenesis, different osteotomy lines were selected according to the characteristics of the mandibular deformity: (1) For short mandibular body, the straight osteotomy line was used to extend the mandibular body. (2) For short mandibular ramus, a polygonal osteotomy line was used to extend the ramus. (3) For the increased mandibular angle, a curved osteotomy line was used to change the angulation.@*Results@#Linear osteotomy was used in 38 patients, polygonal line osteotomy were used in 129 patients, and curved osteotomy was performed in 41 patients. Among them, 4 patients with linear osteotomy had deciduous embryo injury, 6 patients with linear osteotomy and 2 patients with polygonal osteotomy had open occlusion, and patients with curved osteotomy did not have tooth and mandible damage, or malocclusion. All patients were followed up for 3 months to 5 years. The average follow-up time was 6.2 months. All osteotomy healed well, without osteonecrosis or nonunion.@*Conclusions@#For the mandibular distraction osteogenesis, osteotomy line could be individualized, according to the characteristics of mandibular deformity of infants and young children, which can reduce complications such as dental damage and open occlusion.
RESUMO
Objective To design safe and beautiful curved osteotomy line for mandibular angle osteotomy .Methods Expo‐sing 150 cases(300 sides) of mandible tube in the mandible bone of adults;Observing the characteristics of the movement of man‐dibular canal;measuring the distance from the critical dot of mandibular canal to marginal mandibular ;observing the positional rela‐tionship between mandibular foramen and the inferior alveolar arch;designing the curved osteotomy line based on observations to meet the individual needs .Results T he distance betw een the key points of mandibular canal A1 ,B1 ,C1 ,and D1 ,E1 and the mandib‐ular edge come as (14 .02 ± 2 .23)mm ,(21 .06 ± 3 .90)mm ,(14 .08 ± 3 .68)mm ,(13 .60 ± 2 .80)mm ,(14 .55 ± 3 .34)mm ,respective‐ly ;the maximum width each were (10 .05 ± 4 .00)mm ,(15 .06 ± 2 .88)mm ,(8 .08 ± 3 .88)mm ,(6 .09 ± 3 .45)mm ,(7 .06 ± 3 .56) mm ;the probability that mandibular foramen and inferior alveolar of the bow was located in the same plane falls on 96% ;the rear end of the point A of the osteotomy line should not be higher than the plane of the lower jaw holes ,the front point of three osteoto‐my line C ,D ,E ,fall respectively on the point intersection where the vertical line led downward via the edge of the ramus ,the man‐dibular teeth M2 ,P4 met the marginal mandibular .Conclusion The design of curved osteotomy line for mandibular angle osteotomy meets the individual needs ,in line with the anatomical features and aesthetic requirements which takes the advantages as easy‐opera‐tion with clear signs ,high security and preferable effect after operation .