Discussion

This case report describes two approaches for immediate replacement of a failing primary canine and an impacted secondary canine, viz. one for impacted cuspids located at the buccal side of the maxilla and one for impacted cuspids located at the palatal side of the maxilla, by an immediately placed and provisionalized single implant. With both approaches, esthetically satisfying results were achieved, comparable with other case reports. Removal of an impacted canine causes an evident bone defect, which can be a possible limitation of the proposed technique, because it may be difficult or even not possible to place the implant with enough primary stability.

In order to preserve as much bone as possible during the surgical removal of the impacted tooth, it is important to localize the impacted tooth and to judge whether a buccal or palatal approach will preserve most of the native bone by three-dimensional radiographical imaging. Such an approach is supported by recent literature claiming that evaluation of a CBCT image favors treatment planning. Even though in both cases, a significant amount of bone had to be removed to expose the impacted cuspid, proper pre-operative planning still allowed for immediate implant placement and immediate provisionalization because of enough primary stability of the implant.

Characteristic for the bone defect in both cases was preservation of the coronal part of the alveolar crest, especially the labial bone plate. According to Kan et al. the presence of ideal pre-existent soft and hard conditions are a prerequisite for immediate implant placement and provisionalization. Particularly, an intact labial bone plate is important to minimize facial gingival recession.

Furthermore, an implant system was used, which claims to achieve good primary stability in a small amount of bone, which allowed for immediate provisionalization. This is consistent with recent literature that claims when good primary implant stability is achieved, in the presence of sufficient bone volume, single implants should be provisionalized immediately for preservation of the pre-operatively existing tissue conditions in order to achieve a favorable esthetic outcome.

But, in order to avoid significant facial hard and soft tissue loss due to the remodeling process after tooth extraction, jeopardizing the final esthetic result, a bone grafting procedure is necessary.

Although immediate implant placement and provisionalization is a desired treatment option, it is not possible to apply to young still growing patients. In this case, orthodontic treatment or autotransplantion are indicated.

In addition, a primary canine is smaller in all dimensions, but especially in its mesio-distal dimension, compared to a secondary canine. In order to place an implant crown with comparable dimensions as the contralateral secondary canine to achieve symmetry, sufficient mesio-distal space is needed. This can be a limitation of the proposed technique because when insufficient space is available, orthodontic treatment is still needed to create enough space for an implant crown with an anatomical design.

It is concluded that under premise of preservation of sufficient bone to achieve primary stability of the implant, removal of the canines can be combined with immediate placement and provisionalization of the implant.