▋ Introduction

The patient is a 65-year-old female who previously received implant treatment at another institution. Ten years later, the implants failed, and she was referred to our hospital for full-arch maxillary reconstruction.

There is severe maxillary bone deficiency, particularly in the anterior and left regions, with residual bone thickness of only 2–3 mm.

▋ Treatment Plan

On the right side, previously placed implants are still present. After identifying the original implant system, corresponding prosthetic components can be used as supports for the All-on concept.
At position #13, sufficient bone remains for placement of a conventional implant.
In the midline region, bone availability will be evaluated for potential implant placement. If feasible, this would help increase the AP spread.
#25 zygoma: classified as ZAGA type 4.
At #23, although a zygomatic implant was considered, the patient’s zygoma is relatively small. Placing two implants on the same side may result in insufficient space; therefore, a trans-nasal technique is selected instead.

▋ Trans-nasal Implant

Serves as anterior support in an All-on-X treatment.
If an anterior zygomatic implant is not suitable, the bone condition in this region can be evaluated as an alternative.
The bone between the inferior nasal concha and the maxillary wall is usually dense; excessive underpreparation should be avoided.
An angled MUA is typically required for prosthetic correction, and the implant length is generally 18–20 mm.