Purpose: This clinical trial was conducted to evaluate the biologic and prosthetic complications that may occur after one year of using either telescopic PEKK/Zircon overdentures (TOD) or fixed screw retained hybrid prosthesis (FHP) in completely edentulous lower cases that have four widely distributed implants.
Materials and methods: Ten participant received four parallel implants in the canine and first molar areas. They were divided randomly in to two groups: Group 1 received FHP and Group 2 received TOD. Biological and prosthetic complications were measured immediately and after one year from prosthesis insertion for comparison. Chi-square test was used to compare between groups.
Results: In both groups no implant failure reported. There was no significant difference regarding implant failure, implant survival, pain, swelling, abscess, fistula formation, peri-implantitis, peri-implant mucositis, bleeding on probing between groups. There was no complication reported regarding cylinder fracture nor abutment fracture or prosthetic screw fracture. But screw loosening of the telescopic abutment and prosthetic screw in the TOD and FHP respectively was noticed. In the prosthetic level, a significant (P=*0.010) complication was reported in the form of wear in opposing complete dentures teeth in the FHP group.
Conclusion: FHP and TOD can be used successfully for rehabilitation of completely edentulous mandible treated with four widely distributed implants with favorable biologic and prosthetic outcomes after one year. Telescopic implant overdentures have superior soft tissue condition related to easy hygiene accessibility by patients. Using PEKK is a promising choice in the construction of implant supported fixed or removable prosthesis.