Objectives To assess the effects of piezocision on the rate of mandibular second molar protraction. Materials and Methods Thirty-one subjects (average age: 22.26 ± 5.63 years) who presented with at least one extracted mandibular first molar were selected to participate in the study. The subjects were subdivided into one of two groups, 22 molars each: group 1, where piezocision was performed immediately before molar protraction and group 2, where molar protraction was performed with no piezocision. Piezocision was performed by making two vertical incisions mesial and distal to the extraction space, and bone cuts were done with a length up to the mucogingival line at a depth of 3 mm. The rate of second molar protraction, duration of space closure, and level of interleukin-1-β (IL-1β) in gingival crevicular fluid (GCF) during the first month of space closure were recorded. Results During the first 2 months after surgery, the rates of second molar protraction were 1.26 ± 0.12 mm/month and 0.68 ± 0.19 mm/month in the piezocision and no piezocision groups, respectively (P < .001). Duration of lower first molar space closure was 9.61 ± 0.98 months in the piezocision group and 10.87 ± 1.52 months in the no piezocision group (P < .01). The level of IL-1β in GCF was higher in the piezocision group compared to the no piezocision group, up to 1 week after surgery (P = .02). Conclusions Although piezocision doubled the rate of second molar protraction during the first 2 months after surgery, overall second molar protraction was increased by only 1 month.

Objective: To compare second molar protraction between early, late and no piezocision groups. Material and Methods: Forty subjects with bilaterally extracted mandibular first molars were selected to participate in the study. Subjects were subdivided into two groups: piezocision and no piezocision. The piezocision group was further subdivided into two subgroups: early piezocision (piezocision performed immediately before second molar protraction) and late piezocision (piezocision performed three months after starting molar protraction). In the no piezocision group, molar protraction was done without surgery. The intervention (piezocision group and timing of piezocision/side within group) was randomly allocated using the permuted random block size of 2, with 1:1 allocation ratio. The amount of second molar protraction, duration of space closure and anterior anchorage loss were measured. A repeated measures analysis of variance was conducted to define the differences between the measured variables at the different time intervals. Differences between groups were assessed using ANOVA test. Results: No difference was detected between early and late piezocision groups in the amount of molar protraction at the end of space closure. Duration of complete space closure was 9 and 10 months in the piezocision and no piezocision groups. Anchorage loss was similar between the three studied groups. Conclusions: Early and late piezocision have similar effect and both increased the amount of second molar protraction temporarily in the first 2-3 months after surgery. Duration of mandibular first molar space closure was reduced by one month when piezocision was applied. Anchorage loss was similar in the three groups.

Objectives To assess the effect of piezocision on periodontal tissues and alveolar bone height and to detect lower second molar root resorption in piezocision-assisted mandibular second molar protraction compared to no-piezocision molar protraction. Materials and Methods Twenty-one subjects (four males, 17 females, aged 22.43 ± 2.83 years) who presented with bilateral extraction of lower first molars were included. The patients were divided into two groups; Group 1: Piezocision-assisted molar protraction (right or left side of subjects) in which piezocision was performed immediately before lower second molar protraction and, Group 2: No-piezocision molar protraction in which lower second molar protraction was not surgically assisted. Plaque index (PI), gingival index (GI), periodontal pocket depth (PPD), width of keratinized gingiva (WKG), gingival recession (GR), lower second molar mesial root resorption, alveolar bone height, and mandibular bone height were recorded at T1 (immediately before molar protraction) and at T2 (after second molar space closure). Results In the piezocision-assisted molar protraction group, significant changes were detected in the WKG (P < .001), GR (P < .05), and the mandibular bone height (P < .001). Compared to the no-piezocision group, piezocision-assisted molar protraction resulted in an increased WKG (P < .001) and less second molar mesial root resorption (P < .01). Conclusions Piezocision does not have any detrimental effect on the periodontium and produces less root resorption.