Vu Orthodontics - Orthodontics, Periodontics, and Implants

Introduction

A natural tooth should be saved first, and a dental implant should be the last option.

Poor Implant Placement

A case of bad implant placement (which was done elsewhere) is shown in Fig. 1. In this case, the implant was placed not parallel to the adjacent roots.  Its axis should be along the yellow line -- not the red one. It was also placed too deep.  More importantly, the implant is of the wrong type.  It is a tissue-level implant (of Straumann), so the top part of the implant should be above the bone level -- should not be below the bone level, as shown.

Fig. 1. Bad implant placement: the axis is supposed to follow the yellow line, not the red one.

Another case of poor implant placement (which was done elsewhere) is shown in Fig. 2. In this case, the implant (in the middle) caused a damage to the adjacent natural tooth.

Fig. 2. Another poor implant placement

Another case of bad implant placement (which was done elsewhere) is shown in Fig. 3 (photo) and Fig. 4 (cross-sections of the CBCT scan). In this case, the implant is almost completely out of the bone. The site is of the upper right second premolar (Tooth #4). Even if the dentist had placed the implant in a perfect position and orientation, the bone width (in buccal-palatal direction) would still have been too small for this implant (6.22 mm, measured at the implant-platform level). According to the patient, the dentist who placed three (3) implants on him. But two (2) fell out, and only one remains. The dentist took some radiograph(s), presumably, PA or BW or both, and then told the patient, "The bone looks good."

Fig. 3. Implant for Tooth #4 site is outside of the bone and protruding under the soft tissue (photo)

Fig. 4. Implant for Tooth #4 site is outside of the bone (CBCT scan, with buccal-palatal cross-section)

Good Implant Placement

The following are examples showing good implant placements (which were done by the author), using a fully-guided system.

Single Implants

In this case of a single implant, a fully-guided system is used. The implant is perfectly placed center, between the roots of the two natural teeth (Fig. 5). PA means periapival; BW means bitewing. The implant is placed such that its platform is about 0.5-1 mm apical from the alveolar crest.

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Fig. 5. A good implant placement: (a) implant and healing abutment (PA view), (b) implant and healing abutment (BW view), and (c) implant, implant abutment, and implant crown (PA view, a month later)

Another example shows a good implant placement (which was done by the author, Fig. 6), using a fully-guided system.

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Fig. 6. A good implant placement, showing implant and cover screw: (a) PA view, (b) BW view

Multiple Implants

The following is an example of a multi-implant case, in which there is no room for error.  Thus, a fully-guided system must be used for implant placement (Figs.7 & 8)

Fig. 7. A multi-implant case, fully guided (Sites #12, #13, and #14): planning

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Fig. 8. A multi-implant case, using fully guided sytem, Sites #12, #13, and #14 -- implants and cover screws: (a) PA, and (b) BW

Note that for Site #14, the implant was tilted a bit to the mesial side (compared to the planning).