Sinus floor augmentation has been proven an effective treatment procedure to increase bone volume in the posterior edentulous maxilla. Autogenous bone considered to be the best material for reconstructive bone surgery and has been successfully used as a graft material to augment posterior maxilla. However, the collection of autogenous bone required extra risks for morbidity and complaints. So, various bone graft materials included ${eta}$-tricalcium phosphate(${eta}$-TCP) has been introduced for replacing the autogenous bone. The objective of this clinical study was to determine the predictability of endosseous implant placed in a maxillary sinus with ${eta}$-TCP grafting. We performed sinus elevation with ${eta}$-TCP to install the implant in the 10 maxillary cases. The prosthetic procedure was performed 6-9 months after. The implant-prosthetics was checked about 1 year. We checked the implant and measured the maximum bite force to evaluate the function of the implant. There was not observed the specific problem and complication in dental implant and maxillary sinus in the grafted materials. The maximum bite force was 558N in case of natural tooth, 365N in implant without grafting, 318N in implant with ${eta}$-TCP grafting. There was no significant difference between with and without sinus grafting on maximum bite force(p>0.05). As though the long term check-up is needed, the grafting of ${eta}$-TCP as a osteoconductive materials can expand the volume and induce dense new bone formation in maxillary sinus. So, this short-term results support that ${eta}$-TCP can be a suitable material for sinus augmentation.