Angular changes in implants placed in the anterior maxillae of adults: a cephalometric pilot study

Completion of adolescent growth represents the earliest time point for implant placement, yet craniofacial growth persists into adulthood and may affect implant position. We aimed to assess whether implants placed in the anterior maxillae of adults show angular changes over time.

We conducted a cephalometric pilot study in postpubertal patients with no growth disorders, skeletal malformations, or parafunctions. The patients received a single implant in the anterior maxilla and no orthodontic or orthognathic treatment afterwards. We measured angular changes of implants and central incisors on cephalograms taken immediately and after at least 5 years postoperatively with the Sella-Nasion line (SNL) and the nasal line (NL) as references. Changes in implant-SNL angles were the primary outcome.

In 21 patients (30.2 ± 11.5 years at surgery) after a mean follow-up of 8.6 ± 1.3 years, implant-SNL angles and implant-NL angles changed in 81% and 57% of implants, respectively. Implant-SNL changes ranged from 3° counterclockwise to 4° clockwise and were more prevalent in males (100% vs. 58%) and patients under 30 at surgery (85% vs. 63%); mean absolute differences were larger in males (1.8 ± 1.0° vs. 1.3 ± 1.4°) and patients under 30 at surgery (1.5 ± 1.4° vs. 1.1 ± 1.4°). Incisor-SNL angles and incisor-NL angles changed in 89% and 32% of incisors, respectively.

Implants placed in the anterior maxillae of adults show modest angular changes over time.

Changes in implant angles have potential functional and esthetic consequences.