Accelerated Mandibular Molar Protraction: Piezocision at the Time of Molar Protraction or Later?

Detailed Description: Thirty-five subjects who presented with bilaterally extracted mandibular first molar were selected to participate in the study. The subjects were subdivided into one of 3 groups as follows: group 1 consisted of 20 subjects /20 molars where piezocision was performed immediately before molar protraction; group 2 consisted of 20 subjects/ 20 molars where molar protraction was carried on after 3 months of molar protraction with no piezocision; group 3 consisted of 20 subjects (40 molars) where protraction was carried out with no piezocision.

After reaching 0.019X0.025" SS arch wire, NiTi coil spring was used for space closure (protraction force was 150g) attached from the lower second molar hook to the head of the mini-screw. Piezocision was performed by making 2 vertical incisions mesial and distal to the extraction space. Piezotome was inserted in the incisions previously made and bone cuts were done with a length up to mucogingival line and depth of 3 mm. Gingival crevicular fluid (GCF) sample was obtained from the mesiogingival side of the lower second permanent molar with use of Periopaper. GCF sample was repeated 1 day, 1 week and 4 weeks after molar protraction with piezocision or with no piezocision. Periodontal parameters were measured and lower molar root resorption was assessed using Perapical radiographs.

Inclusion criteria

• Age range from 19 to 30 years
• Bilaterally extracted mandibular first molar (first molar extracted more than one year ago and with a residual extraction space of more than 6 mm).
• Class 1 malocclusion where molar protraction is indicated.
• All permanent teeth are present except for the extracted mandibular first molars.
• Healthy periodontium (gingival index score ≤ 2, plaque index score ≤ 2 and probing depth < 4mm)

Exclusion criteria

• Previous orthodontic treatment
• Any systemic disease
• Smoker
• Poor Oral hygiene