Background This study aims to prospect the soft and hard tissue changes after augmentation of two diferent local mandibular
contour defects using polyetheretherketone (PEEK) patient-specifc onlay implants.
Methods Six patients with disfguring local mandibular deformities were included in this study (fve males and one female)
and received seven PEEK patient-specifc implants (PSI), virtually designed and surgically settled to augment seven man-
dibular defects, three defcient chins, and four mandibular angels. The analysis of the soft and hard tissue changes utilized
the superimposition of the preoperative and the 6-month postoperative sagittal and coronal CT views, after standardizing
the radiographic interpretation.
Results The soft tissue gain for the chin was 6.8 mm±0.98 with a 45.8% increase versus 4.42 mm±0.41 with a 22.9%
increase for the angle. The diference in the soft tissue gain between the two groups was statistically signifcant (P=0.0001).
Comparing the soft tissue gain to the planned implant thickness, the percentage of the soft tissue gain for the chin recorded
109.2% versus 65.57% for the angle. The diference between the two groups was also statistically signifcant (P<0.0001).
Conclusion PEEK patient-specifc onlay implants represented an efcient and straightforward modality to augment local
mandibular contour deformities with favorable esthetic outcomes; the total soft tissue profle gain of the chin region mark-
edly exceeded that of the mandibular angle.
