Effects of growth hormone on initial bone formation around dental implants: a dog study.
OBJECTIVE
The aim of this study was to evaluate the effects of topical application of growth hormone (GH) on the osteointegration of dental implants in dogs at 5 and 8 weeks after surgery.


METHODS
Mandibular premolars and molars were extracted from 12 Beagle dogs. Four screw implants were placed in each mandible. Before implant placement, 4 IU of GH were applied to the test sites (TS); no treatment was applied to control sites (CS). Morphometric parameters, bone-to-implant contact (BIC), peri-implant connective tissue, interthread bone and newly formed bone were measured. The Student's t-test for was used for statistical analysis of data obtained.


RESULTS
After 5 weeks of treatment, BIC values varied slightly between 34.33 ± 2.35% (CS) and 35.76 ± 2.96% (TS). Interthread bone tissue was 64.08 ± 8.68 at CS and 72.86 ± 2.93 at TS, with statistical significance (P<0.05). Bone neoformation was 72.53 ± 4.54 at the CS and 80.74 ± 1.65 for the GH group, these being statistically significant differences (P<0.05). After 8 weeks, BIC had slightly increased for the GH group (36.47 ± 3.09 vs. 39.61 ± 2.34). Interthread bone was 80.57 ± 2.28 at the CS and 82.58 ± 2.44 at the GH site, which was statistically significant. Bone neoformation was 88.09 ± 1.38 at CS and 91.01 ± 1.52 at TS, showing statistical significance (P<0.05).


CONCLUSIONS
Topical application of 4 IU of GH like a biomimetic agent at the moment of implant placement has no significant effects on the BIC at 5 and 8 weeks, although bone neoformation and inter-thread bone values did increase significantly.
Department of General Dentistry, Faculty of Medicine and Dentistry, University of Murcia, Murcia, Spain. josecalvog@ono.com
José Luis
JL
Calvo-Guirado
Jose
J
Mate-Sanchez
Rafael
R
Delgado-Ruiz
Maria Piedad
MP
Ramirez-Fernández
Antonio
A
Cutando-Soriano
Monica
M
Peña
D000287:Administration, Topical; D016301:Alveolar Bone Loss / Q000473:pathology; D000818:Animals; D001641:Bicuspid / Q000601:surgery; D003238:Connective Tissue / Q000187:drug effects / Q000473:pathology; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D004285:Dogs; D005240:Feasibility Studies; D013006:Growth Hormone / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008334:Mandible / Q000187:drug effects* / Q000473:pathology / Q000601:surgery; D008963:Molar / Q000601:surgery; D016348:Osseointegration / Q000187:drug effects*; D010012:Osteogenesis / Q000187:drug effects*; D010519:Periodontium / Q000187:drug effects / Q000473:pathology; D011897:Random Allocation; D011994:Recombinant Proteins; D013997:Time Factors; D014081:Tooth Extraction; D020390:Tooth Socket / Q000187:drug effects / Q000473:pathology / Q000601:surgery
D015921:Dental Implants; D011994:Recombinant Proteins; D013006:Growth Hormone