so that the direction and topography of the residual ridge becomes evident.

2. be large enough so that the blood supply is maintained.

3. be a full thickness mucoperiosteal flap.

4. hemostasis should be obtained and hematoma formation should be prevented as much as possible.

5. the flap should be sutured into place at the end of the blade insertions and immobilized wherever necessary.

6. If a bony defect is to be covered, the flap margins should rest on a solid bony base.

7. In cases where there is a near dehiscency of the mandibular canal and mental foramina or both, the incision must always be on the lingual side of the ridge.

The blood supply to a flap may be maintained either by incorporating an artery in the flap or by making the attached base of the flap larger than the free margin.

All the soft tissues must be handled carefully to avoid crushing, tearing or other trauma.

All pathologically involved teeth that cannot be saved by apicoetomies, infra-bony pocket removals, etc. should be extracted prior to implant insertions. Where two or more teeth are removed and are adjacent to each other a minimum of 4 to 6 months should elapse before implants are inserted.

When teeth are to remain as part of the implant prosthesis, but deep bony pockets exist, one or two procedures can be done. Either refer the patient to a periodontist before the implant surgery or remove the infra-bony pockets when the bone is exposed at the time of implant intervention.

A well balanced prefabricated fixed temporary acrylic splint should be carefully designed and processed prior to this appointment.

Whereas sometimes the preservation of the labial cortex at the expense of the inter-radicular medullary bone (according to Dean and Obergeiser) is needed for full denture procedures this never becomes necessary with implants. In implantology the canine eminences and the bucco-lingual thickness as well as alveolar height should remain ideally the same in the arch.

Alveoloplasties should only be done in those situations where, either because of an immediate extraction or an error in cutting away too much soft tissue so that the tissues can easily be sutured

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