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Updated: May 27, 2026

The Establishment of a Murine Mandibular Molar Extraction Socket Healing Model
Published on: January 13, 2023
Spontaneous eruption of impacted second molars
Giampietro Farronato1, Lucia Giannini, Guido Galbiati
1Department of Orthodontics, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy. giampietro.farronato@unimi.it
Objectives:
To propose a treatment protocol for the management of impacted second molars.
Materials And Methods:
Patients were randomly divided into two equal groups (20 patients in each). The patients in the first group underwent a surgical removal of the mucosa covering retained teeth; the second group was the control group and patients were not treated but only observed. The total number of retained teeth considered were 66 (34 in the first group and 32 in the control group). A Chi squared test has been performed to compare the prevalence of eruption in the two groups. We compared the frequency of eruption for the treatment compared to the control group by calculating the risk ratio (RR) and 95% confidence interval (95% CI).
Results:
Eruption occurred in 32 teeth after surgical removal of the mucosa while in the control group only 3 teeth erupted in the considered period. The difference between the two groups showed statistically significant. Among the non erupted teeth, 20 were positioned with a mesial inclination and 12 were positioned vertically.
Conclusions:
The results show that the removal of the mucosa covering teeth allows in several cases second molars to erupt. It's a conservative method which doesn't exclude the possibility of a successive different therapy. Therefore it must be considered among the treatment options during treatment planning.
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