Effect of scanned arch, level of recording, and recording technique for trueness and marginal fit of complete arch implant-supported fixed dental prostheses

Yilmaz B., ÇEVİK P., Kahveci Ç., Abou-Ayash S., Çakmak G.

Journal of Prosthetic Dentistry, 2026 (SCI-Expanded, Scopus)

Özet

Statement of problem: The combined effect of the arch scanned, recording level (implant versus multiunit), and recording technique on the trueness and fit of complete arch implant-supported fixed dental prostheses (CAISFDPs) is not well known. Purpose: This study aimed to investigate how the recording level, recording technique, and dental arch affect the trueness and fit of CAISFDPs. Material and methods: Maxillary and mandibular casts with 2 straight anterior and 2 tilted posterior implants (4.5×12 mm) were digitized using an industrial scanner (Artec Micro II). Recordings were made either digitally using an intraoral scanner or conventionally using an open-tray technique, either multiunit abutment or implant level (n=7). Laser-sintered titanium frameworks were fabricated. The framework trueness and average gap values were analyzed for the effect of recording type, level, and arch by using a metrology-grade software program (Geomagic Control X). The correlation analyses between trueness and average gap values were performed using the Pearson correlation test (α=.05). Results: Recording level (P>.79), recording technique (P>.74), and their interaction had no significant effect (P>.99) on mandibular framework trueness. Frameworks fabricated from abutment-level recordings had lower RMS values than those fabricated from implant-level recordings (P<.001). In contrast, no significant differences were observed between digital scans and conventional recordings at either the implant or abutment level (P>.05). Maxillary framework trueness was not influenced by the recording technique (P>.05). For the maxilla, digital scans resulted in lower average gap values than conventional recordings (P=.005). The average gap values ranged between 40.1 and 242.1 µm. A negative correlation was observed between framework overall trueness and average gap values for mandibular digital scans (r=−.821, P=.023). Conclusions: Digital abutment- and implant-level scans resulted in high manufacturing trueness and fit in both arches, comparable with those of frameworks manufactured by using conventional recordings.