Immediate implant loading with fixed dental restorations: An animal model study

Abstract

Background/Aim. Immediate loading is considered to be the most innovative technique in contemporary implant dentistry. Recent clinical and experimental findings have demonstrated that only implants with high primary stability can be subjected to immediate loading protocol with predictable results. It is generally accepted that the most important prerequsite for successful osseointegration is achievement and maintenance of implant stability. The aim of this in vivo study was to investigate the possibility for successful application of immediate loading protocol in implant systems with different surface properties. Methods. In the experimental study 2 mongrel dogs were edentulated bilaterally in the mandibular and maxillary premolar areas. After 3 months implants were placed in a pattern 4 different commercially available implants per quadrant (n = 32): Mk III TiUnite (Nobel Biocare, Sweden), ITI TPS (Straumann, Switzerland), 3IOsseotite (Implant Innovation, USA) and XiVE Cell-Plus (Friadent, Germany). Implants were subjected to immediate loading with 4 unit gold cast bridges, 2 days post implantation. The assessment of implant stability and immediate loading possibilities were done by performing Resonance frequency analysis (RFA). Results. After a 6- month loading period all bridges were in function and all implants occurred well osseointegrated. When summarizing the Implant Stability Quotient (ISQ) values, it was noted that resonance frequency was significantly higher for mandibular implants. The results of this experimental setting showed that all evaluated surfaces achieved good implant stability. Increase of ISQ values was found for all implants in the mandible and partially decrease of ISQ values for maxillary implants after 6 months of functional loading with 4 unit bridges. Conclusions. Investigated endooseal implants did not show different degree of osseointegration, because there was not statistically significant difference among observed parameters (ISQh i ISQp) between implant systems.

Uvod/Cilj. Imedijatno opterećenje implantata smatra se jednim od najznačajnijih dostignuća savremene dentalne implantologije. Rezultati novijih kliničkih i eksperimentalnih studija pokazali su da samo implantati visoke primarne stabilnosti mogu biti izloženi protokolu imedijatnog opterećenja zubnom nadoknadom sa predvidivim ishodom. Cilj studije bio je da se ispita mogućnost uspešne primene protokola imedijatnog opterećenja implantata različitog mikrodizajna fiksnim zubnim nadoknadama. Metode. U eksperimentalno istraživanje uključena su dva psa, obezubljena obostrano u premolarnoj regiji gornje i donje vilice. Nakon tri meseca od ekstrakcije zuba, ugrađena su, po predviđenoj šemi, četiri različita implantata po kvadrantu (n = 32): Mk III TiUnite (Nobel Biocare, Sweden), ITI TPS (Straumann, Switzerland), 3I-Osseotite (Implant Innovation, USA) i XiVE Cell-Plus (Friadent, Germany). Implantati su imedijatno opterećeni fiksnim zubnim nadoknadama, četvoročlanim mostovima od plemenite legure zlato-platina, dva dana posle implantacije. Stabilnost implantata i mogućnost imedijatnog opterećenja ocenjivana je na osnovu analize rezonantnih frekvencija (RFA). Rezultati. Šest meseci nakon implantacije i imedijatnog opterećenja fiksnom zubnom nadoknadom, svi mostovi bili su u funkciji i svi implantati uspešno integrisani, ne pokazujući znake mobilnosti. Sumiranjem dobijenih vrednosti koeficijenta stabilnosti implantata (ISQ) ustanovljeno je da su rezonantne frekvencije bile značajno veće kod implantata u donjoj vilici. Rezultati eksperimentalnog istraživanja pokazali su da su sve analizirane površine ostvarile dobru implantatnu stabilnost. Utvrđen je porast ISQ vrednosti kod svih implantata u mandibuli i delimičan pad ISQ vrednosti za implantate u maksili, nakon šest meseci funkcionalnog opterećenja fiksnim zubnim nadoknadama. Zaključak. Ispitivani endoosealni implantati nisu pokazali različit stepen oseointegracije jer se rezultati merenih parametara hirurških (ISQh) i protetkih (ISQp), nisu statistički značajno razlikovali između implantatnih sistema.