The purpose of this study was to compare and evaluate the bone formation and stability changes of the immediately loaded
implants by different temporary crown units.
In 10 Mongrel dogs, right and left 1st, 2nd and 3rd mandibular premolars were extracted bilaterally. After 2 months, implants were
placed at the extracted wound sites. Total 60 fixtures were placed following the standard protocol. Implants used were Neobiotech
implants (∅4.0mm×10mm, Internal system). Temporary acrylic resin crowns were prepared and adjusted to those sites for
immediate loading. Single unit immediate loading temporary crown was prepared for position number 1; 2 units immediate
loading temporary crown were prepared for position number 2 and 3; and 3 units immediate loading temporary crown were
prepared for position number 4, 5 and 6. Two animals were sacrificed at 1, 2, 4, 8, and 16 weeks after the implants insertion. RFA
(Ostell mentor) and PTV (Periotest) were measured at the time of insertion and sacrifice. Histomorphometric examinations were
done. BA (bone area) and BIC (bone to implant contact) were measured by KAPPA IMAGE BASE. The 2-way ANOVA were
undertaken for statistical analysis (p<0.05).
In this study, most of the immediately placed implants were healed without inflammation in clinical examination, but some of
them showed radiolucency at the crest. Three different temporary crown units of implants showed a little difference in the
measured values during the early healing period. All implants showed reduced stability at 2 weeks. RFA, PTV were no statistical
differences among 3 different temporary crown units of implants. BA and BIC also showed no statistical differences among 3
different temporary crown units of implants at 8 and 16 weeks (p<0.05). There were no statistically significance on the stability
and bone formation between 3 different temporary crown units of implants.
Further studies may be necessary with different conditions such as immediate loading, increased number of specimens, and
improved measuring methods. [THE JOURNAL OF THE KOREAN ACADEMY OF IMPLANT DENTISTRY 2011;30(1):33-43]