Orthodontic patients may need dental implants either to replace missing teeth after optimal space management or to facilitate orthodontic movement by providing an additional anchorage.

Dental Implants for Patients with Tooth Agenesis

Optimal Time for Implantation

The replacement of teeth by implants is usually restricted to patients with completed craniofacial growth. In the last few years, an exception to this restriction was reported in children suffering from extended hypodontia or even anodontia.

In cases of residual growth after implant placement, the dental implant will not follow the migration of the alveolar process, leading to disharmony between implant and adjacent teeth. Consequently, it is essential to evaluate the completion of alveolar bone growth before implant placement in esthetic areas. In general, this happens around 18 years old. However, wide variation is observed among different face types. No changes with the superimposition of cephalometric radiographs taken 6 months apart is a good evaluation process (Heij et al., 2006).

Orthodontic space opening should allow for adequate intercoronal and inter-radicular space for optimal implant placement. As it is usually performed during adolescence, an effective provisional retention device (resin-bonded bridge) must be placed to prevent coronal and apical migration.

Alveolar Bone Dimensions

Agenesis is often associated with insufficient bone growth and poor bone density. Bone augmentation procedures are indicated before or during implant placement.

Dental Implants Used As Orthodontic “Absolute” Anchorage

Special Implants: Orthodontic Miniscrews

Definition

A special implant is a dental implant with a diameter of less than 3 mm. It is used for a limited period of time and should not be confused with the narrow implants which are used for regular cases for which a long-term osseointegration is required. The terms “mini-implants,” “microimplants,” “miniscrews” or “microscrews” are often used as synonyms (Table 44.1). Mini-implants are considered as an effective source of anchorage by orthodontists (Reynders et al., 2009) (Fig. 44.1). Therefore, the term “orthodontic implant” is/>