A dental implant system, comprising: a dental implant, the dental implant comprising: an apical end; a top end; an anchoring portion adjacent the apical end and adapted to engage bone and having an axial length; an abutment receiving portion having at least one longitudinal groove of a selected shape extending downwardly a predetermined length from the top end of the dental implant; an annular shoulder formed between the anchoring portion and the abutment receiving portion; and an internally threaded opening of a predetermined depth accessible from the top end of the dental implant; an implant abutment having a peripheral wall and a central axial bore extending through the abutment, the abutment bore having a lower part and an upper part; the upper part of the abutment bore being adapted to receive a key in a fittingly close relationship; the lower part of the abutment bore having a conical interior wall adapted to form a locking taper connection with the abutment receiving portion of the implant which is tapered toward the top end; and a key having an outer wall for being received in the upper part of the abutment bore in a fittingly close relationship; the key having at least one axially projecting member extending outwardly from one end thereof and adapted to releasably mate with the corresponding at least one longitudinal groove of the abutment receiving portion. a dental implant, the dental implant comprising: an apical end; a top end; an anchoring portion adjacent the apical end and adapted to engage bone and having an axial length; an abutment receiving portion having at least one longitudinal groove of a selected shape extending downwardly a predetermined length from the top end of the dental implant; an annular shoulder formed between the anchoring portion and the abutment receiving portion; and an internally threaded opening of a predetermined depth accessible from the top end of the dental implant; an apical end; a top end; an anchoring portion adjacent the apical end and adapted to engage bone and having an axial length; an abutment receiving portion having at least one longitudinal groove of a selected shape extending downwardly a predetermined length from the top end of the dental implant; an annular shoulder formed between the anchoring portion and the abutment receiving portion; and an internally threaded opening of a predetermined depth accessible from the top end of the dental implant; an implant abutment having a peripheral wall and a central axial bore extending through the abutment, the abutment bore having a lower part and an upper part; the upper part of the abutment bore being adapted to receive a key in a fittingly close relationship; the lower part of the abutment bore having a conical interior wall adapted to form a locking taper connection with the abutment receiving portion of the implant which is tapered toward the top end; and a key having an outer wall for being received in the upper part of the abutment bore in a fittingly close relationship; the key having at least one axially projecting member extending outwardly from one end thereof and adapted to releasably mate with the corresponding at least one longitudinal groove of the abutment receiving portion.