Primary loading of palatal implants for orthodontic anchorage--a pilot animal study.
OBJECTIVE
This study aimed at evaluating the clinical performance and osseointegration of short orthodontic implants immediately loaded with orthodontic forces.


METHODS
The investigation was designed as an experimental animal study. Eight palatal implants of the Ortho-system were immediately loaded with 100 cN after palatal insertion in 4 female German shepherd dogs. Xylene orange and calcein green were used for polychrome sequential labelling. Histological preparation utilized the cutting and grinding technique. Outcome variables were clinical implant success, histological osseointegration and bone-to-implant contact rates.


RESULTS
All (8/8) implants were clinically successful and stable when the animals were sacrificed. One implant showed fibrous encapsulation and was histologically classified as "failed" for "osseointegration". Upon morphometrical analysis, bone to implant contact rates for newly formed or remodelled bone were 19% at 4 weeks and 26% at 6 months. The fluorochrome labelling indicated substantial mineral apposition on the surface of the implants at the end of the first and the second postoperative months.


CONCLUSIONS
This study revealed borderline reliability of osseointegration for immediately loaded palatal implants but reasonable bone formation at the 4th postoperative week. Thus, two clinical concepts are both supported: early orthodontic loading after 4 weeks as well as improvement of primary stability to provide a biomechanical basis for immediate orthodontic loading.
Borbély
Péter
P
Fogszabályozási Stúdió, Private Practice, Budapest, Hungary.
Dunay
Miklós P
MP
Jung
Britta A
BA
Wehrbein
Heinrich
H
Wagner
Wilfried
W
Kunkel
Martin
M
D000818:Animals; D003799:Dental Stress Analysis; D004285:Dogs; D005260:Female; D020007:Implants, Experimental; D008856:Microscopy, Fluorescence; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation* / Q000379:methods; D016348:Osseointegration; D021362:Palate, Hard / Q000601:surgery; D010865:Pilot Projects; D013997:Time Factors