Immediate loading at single crowns and 2‐unit bridges supported by implants installed in a healed alveolar bony ridge or immediately after tooth extraction. An experimental study in dogs

Abstract

To evaluate presumptive differences in osseointegration at implants installed in healed sites or extraction sockets, supporting either crowns or bridges that were functionally loaded or left unloaded. In six dogs, the mesial roots of the first mandibular molars were treated endodontically. Bilaterally, the teeth were hemisected, and the distal roots extracted. First and second mandibular premolars were extracted as well. After 3 months, the mandibular third and fourth distal roots were extracted after endodontic treatment of the mesial roots. Four implants were installed bilaterally, two in the healed sites corresponding to the second premolar and first molar regions, and two into the extraction sockets. Cobalt-chrome single crowns were prepared and installed in the two most anterior implants, and bridges at the two most posterior implants, bilaterally. A 3-unit bridge was applied to the premolars in the upper jaw only at the loaded sites. All prostheses had a flat occlusal surface and contacts in centric occlusion only at the loaded sites. Three months later, biopsies were retrieved for histological analysis. Higher levels of osseointegration and bone density were observed at the unloaded sites, both at implants installed in healed and post-extraction sites. However, only at implants installed in the post-extraction sites and supporting single crowns, the difference in bone-to-Implant contact was statistically significant. In implant installation immediately following extraction or delayed after three months, osseointegration and bone density were not affected by occlusal contact schemes.

Immediate Loading of Implants Placed in Fresh Extraction Sockets in the Posterior Region. A Systematic Review

“…Survival was de ned as implants remaining in situ during the follow-up period. Only Han et al 25 , Atieh et al 29 and Vigano et al 27 reported RFA values that is ≥70 (95% CI: 77.8-80.3); 76.63 ± 10.65 and 53.8-70.8, respectively. The implant success rate in Atieh et al 29 research was evaluated according to the criteria by Albrektsson & Zarb.…”

“…Two articles were of the animal studies. 27,28 The rest of 8 studies were the controlled clinical trials. 25,26,[29][30][31][32][33] The age range of patients included in these studies was from 15 to 83 years.…”

“…25,26,[29][30][31][32][33] The age range of patients included in these studies was from 15 to 83 years. The age range of the animals is not reported, but Vigano et al 27 report the average age of the dogs tested is 1 year. In animal studies 27,28 after 3 months of loading of implants subjects were sacri ced.…”

“…The age range of the animals is not reported, but Vigano et al 27 report the average age of the dogs tested is 1 year. In animal studies 27,28 after 3 months of loading of implants subjects were sacri ced. One of the researches (Mozzati et al 34 ) was made on partially edentulous mandibles in need of tooth extractions with immediate loading of 4 implants for fullarch rehabilitation.…”