Treatment Planning Guidelines for Proper Implant Placement

04/01/2013 at 5:10 pm #16294

Anonymous

$Figure 1 Failures of fixed and removable implant prostheses: acrylic fracture (Fig 1); and framework fracture (Fig 2).$

Figure 1

$Figure 2 Failures of fixed and removable implant prostheses: acrylic fracture (Fig 1); and framework fracture (Fig 2).$

Figure 2

Figure 3 Conceptualization of stresses and strains encountered for a mandibular prosthesis supported by dental implants. High magnitude masticatory forces (i.) are enacted through long lever arms (ii.), creating bending moments and force magnification in the components (iii.). The forces cause deformation in the prosthesis and challenge the integrity of the implant-abutment interface. The transmitted forces are further encountered at the implant bone interface (iv.).

Figure 3

Figure 4 The mandible must be at least 10 mm in superior–inferior dimension. Rarely are mandibles of less than 10 mm observed clinically.

Figure 4

Figure 5 Accounting for a minimal restorative dimension. A fixed or removable mandibular prosthesis must allow for placement of: (i.) the transmucosal abutment; (ii.) adequate room and access
for peri-implant mucosal hygiene; (iii.) restorative components, abutment, and bridge screws; and (iv.) an esthetic and phonetically accepted veneer.

Figure 5

Figure 6 Defining the depth of implant placement. Implant placement may be at the osseous crest if there is sufficient buccolingual width at that location and sufficient restorative dimension (from the crest to the occlusal plane). However, if these requirements are not met, implant placement is planned in a subcrestal location with a need for accompanying alveolectomy.

Figure 6

Figure 7 A-P spread in clinical situations. Providing a single premolar and a single molar (16.5 mm in length) in the distal cantilever requires approximately 10 mm A-P spread (X) to maintain a 1.5:1 relationship (Fig 7). The parallel placement of the implants resulted in approximately 4 mm to 5 mm of A-P spread (Fig 8). The divergent placement of the implants resulted in approximately 10 mm of A-P spread measured at the abutment/prosthesis interface (Fig 9).

Figure 7

Figure 8 A-P spread in clinical situations. Providing a single premolar and a single molar (16.5 mm in length) in the distal cantilever requires approximately 10 mm A-P spread (X) to maintain a 1.5:1 relationship (Fig 7). The parallel placement of the implants resulted in approximately 4 mm to 5 mm of A-P spread (Fig 8). The divergent placement of the implants resulted in approximately 10 mm of A-P spread measured at the abutment/prosthesis interface (Fig 9).

Figure 8

Figure 9: A-P spread in clinical situations. Providing a single premolar and a single molar (16.5 mm in length) in the distal cantilever requires approximately 10 mm A-P spread (X) to maintain a 1.5:1 relationship (Fig 7). The parallel placement of the implants resulted in approximately 4 mm to 5 mm of A-P spread (Fig 8). The divergent placement of the implants resulted in approximately 10 mm of A-P spread measured at the abutment/prosthesis interface (Fig 9).

Figure 9

Figure 10 Conventional dentures.

Figure 10

Figure 11 Surgical guide.

Figure 11