Soft tissue stability in segmental distraction of the anterior mandibular alveolar process. A 2-year follow-up

Abstract

This study evaluated soft tissue changes in adult patients treated with distraction osteogenesis (DOG) of the anterior mandibular alveolar process and related it to different parameters. 33 patients (27 females; 6 males) were analysed retrospectively before surgery at T1 (17.0 days), after surgery at T2 (mean 6.5 days), at T3 (mean 24.4 days), and at T4 (mean 2.0 years). Lateral cephalograms were traced by hand, digitized, superimposed, and evaluated. Statistical analysis was carried out using Kolmogorov-Smirnov test, paired t test, Pearson's correlation coefficient, and linear backward regression analysis. 2 years postoperatively (T4), the net effect of the soft tissue at point B' was 100% of the advancement at point B whilst the lower lip (labrale inferior) followed the advancement of incision inferior to 46%. Increased preoperative age was correlated (p<0.05) with more horizontal backward movement (T4-T3) for labrale superior and pogonion'. Higher NL/ML' angles were significantly correlated (p<0.05) with smaller horizontal soft tissue change at point B'. Gender and the amount of skeletal and dental advancement were not correlated with postoperative soft tissue changes (T4-T3). DOG of the anterior mandibular alveolar process is a valuable alternative for mandibular advancement regarding soft tissue change and predictability.

Soft tissue stability after segmental distraction of the anterior mandibular alveolar process: a 5.5 year follow-up

“…In the authors' previous study on 33 patients 2.0 years postoperatively, the net effect of the soft tissue at point B 0 was 100% of the advancement at point B while the lower lip (labrale inferior) followed the advancement of incision inferior to 46%. 13 The effects of ageing and soft tissue elasticity have to be considered when analysing long-term effects of maxillofacial surgery on the lips and chin. In his longitudinal Table 4 and labrale inferior could be the missing data from the 16 patients who could not be re-examined for the 5.5 year follow-up.…”

“…The removal of the miniplates could have led to a slight increase in soft tissue change (T4-T3) of point B 0 . 13 In addition, the interface of the surgical section of the anterior aspect of the symphysis was more susceptible to resorption and bony remodelling. 2,14 In conclusion, this long-term follow-up of 5.5 years found that further change in soft tissues occurred between 2.0 and 5.5 years postoperatively regarding point B 0 and labrale inferior.…”

“…2,13 The initial patient sample consisted of 33 Caucasian patients (27 females and six males) aged 16.5-56.0 years (mean age 30.3 years, SD 10.7). Of these 33 patients, 17 patients could be re-examined.…”

“…2,13,14 The net effect of the soft tissue at point B 0 was 100% of the advancement at point B while the lower lip (labrale inferior) followed the advancement of incision inferior to 46% examined 2.0 years postoperatively. 13 Skeletally, 5.5 years after DO the horizontal backward relapse measured À0.3 mm or 8.3% at point B and À1.8 mm or 29.0% at incision inferior. 14 To the authors' knowledge, evaluation of the soft tissue profile and its change in the long-term is lacking.…”

Neurosensory and functional evaluation in distraction osteogenesis of the anterior mandibular alveolar process

“…5,6 Recently, changes in skeletal stability, and soft tissue profile were analysed after DO of the anterior alveolar process. 7,8 Besides the clinical benefits of DO, complications such as neurosensory disturbances of the inferior alveolar nerve are possible. Neurosensory changes in the alveolar nerve were evaluated mainly in animal studies after DO of the whole mandible.…”