Aim: The aim of this study was to evaluate the immediate implant placement 
versus delayed implant placement 3 months later of the splitting of thin alveolar bone 
sites using flapless crest splitting technique. Subjects and Methods: This study was 
designed as a prospective clinical trial of 35 implants over 8 patients with 16 alveolar 
splitting sites. Eight sites were splitted and immediately implanted and submitted to 
group I, the another eight sites were splitted and implanted after 3 months they were 
submitted to group II, After alveolar ridge spiltting both groups were grafted via 
xenografts and covered with collagen membranes for guided bonr regeneration (GTR). 
For both groups we clinically assessed insertion torque, Implant stability quotient 
(ISQ) and radiographically horizontal bone gain and bone density at 3 intervals 
postoperatively, 3 and 6 months.Results: The mean ISQ and insertion torque ± SD in 
group II was higher than group I. Group I showed a higher increase in bone gain than 
group II.Conclusion: Immediate implantation after piezotome ridge splitting can be 
a useful procedure in ridges which have low bone quality and a thin cortex. Delayed 
implantation after piezotome ridge splitting is recommended when the initial stability 
of the implants is predicted to be poor. Both techniques using piezotome alveolar ridge 
splitting are effective in avoiding adjacent nerve injury