odontal condition. Usually insertion of four well-placed blades in the arch supported by a full arch fixed prosthesis prevents any future periodontal disease.

When teeth must be removed that are not too loose, they should be `elevated' out using an elevator and rotating in a mesiodistal direction rather than a labio-lingual or bucco-palatal direction to maintain the labial and buccal plates of bone and all granulation tissue removed from the socket in order to allow new bone to form there. If granulation tissue is left, no bone will grow.

Conservation of the bone for future implants should be the prime purpose when extracting condemned teeth.

When sectioning multi-rooted teeth do not make a buccal flap nor remove any of the buccal cortex. Instead, from the occlusal portion section the roots with a dental bur (700) and carefully elevate each of the roots out mesio-distally or use a narrow beaked pliers.

Often, if that tooth were the terminal abutment and good bone support was present try to save the tooth with root canal and sometimes retrograde amalgams.

Overerupted maxillary molars (or any other teeth) either can be cut down to the C-E junction, root canal be done, some of the bone can be removed immediately superior to the C-E junction and then the root prepared for a full crown restoration thus making enough room available to allow implants to be inserted in the opposing jaw without opening the bite. In those conditions where it becomes impossible then the tooth has to be extracted, the alveolar bone leveled down and in about three months blades can be inserted in the maxilla as well as the mandible with enough inter-occlusal clearance to maintain a proper centric relationship.

Preserving the labial cortex at the expense of the medullary bone in order to collapse the labial cortex palatally, moulding it to the desired contour was fine for a conventional denture, but absolutely superfluous for implants. As much thickness of the bucco-lingual or labio-palatal bone as possible should be maintained before inserting blades to prevent fracturing the bone if it were too thin and to allow a maximum amount of remaining bone to flank the labial and palatal surfaces of the blades in order to act as buttresses of support against anterior and lateral thrusts of the tongue.

I agree where he says "if the immediate reduction of under-cuts will result in a narrow V shaped ridge, then alveoplasty should

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