Implants in the severely resorbed mandibles: whether or not to augment? What is the clinician's preference?

Abstract

Introduction: The aim of this study is to inventory in the Netherlands which therapy is the clinician's first choice when restoring the edentulous mandible.

Material and methods: A questionnaire was sent to all Dutch Oral and Maxillofacial surgeons. As part of this, the surgeons were invited to treat five virtual edentulous patients, differing only in mandibular residual height.

Results: In cases of a sufficient residual height of 15 mm, all surgeons were in favour to insert solely two implants to anchor an overdenture. In case of a residual height of 12 mm, 10% of the surgeons choose for an augmentation procedure. If a patient was presented with a mandibular height of 10 mm, already 40% of the OMF surgeons executed an augmentation procedure. Most (80%) surgeons prefer the (anterior) iliac crest as donor site. The choice of 'whether or not to augment' was not influenced by the surgeon's age; however, the hospital, where he was trained, did. Surgeons trained in Groningen were more in favour of installing short implants in mandibles with reduced vertical height.

Discussion: As the option overdenture supported on two interforaminal implants is reimbursed by the Dutch health assurance, this treatment modality is very popular in the Netherlands. From a point of costs and to minimize bypass comorbidity, surgeons should be more reluctant in executing augmentation procedures to restore the resorbed edentulous mandible as it is dated in literature that also in mandibles with a residual height of 10 mm or less, solely placing implants, thus without an augmentation procedure in advance, is a reliable treatment option.

Fig. 1

An edentulous patient. RH residual height in symphyseal area, in this study varying between 15 and 6 mm

Fig. 2

Different bone augmentation methods used by Dutch OMF surgeons in cases of insufficient mandibular bone height

Fig. 3

The choice of Dutch OMF surgeons to harvest autologous bone grafts

Fig. 4

Number of implants placed in the edentulous mandible

Fig. 5

Suprastructure on implants in the edentulous mandible

Fig. 6

The choice of Dutch OMF surgeons to place two, three, four or six implants or to first restore the available bone volume in relation to the vertical residual bone height