Objectives: To compare between the effect of zirconia and metal CAD/CAM fabricated attachments on alveolar bone height of the residual ridge and periodontal health of abutment teeth in cases with bilateral distal extension base.
Materials and Methods: Seven Kennedy class I patients were selected for this study. In a split-mouth manner, one side of the arch received metal attachment together with porcelain fused to metal fixed partial denture, while the other side received zirconia attachment connected to zirconia fixed restoration. Alveolar bone loss, bleeding on probing (BOP) and pocket depths (PD) were measured for each side at the time of delivery and at 6 and 12 months post-insertion.
Results: There was no statistically significant difference between the two attachments regarding bone loss in the residual ridge in all follow-up appointments. There was also no significant bone loss for each attachment by the end of the follow-up period. There was no significant difference in BOP and PD at 6 months, but there was a significant increase in BOP and PD for both attachments at 12 months post-insertion. However, the difference between the two attachments was not statistically significant at any follow-up appointment.
Conclusions: Zirconia attachment yields comparable clinical and radiographic results as metal attachments for distal extension cases within a follow-up period of one year.