Effect of prosthetic restoration on oral health-related quality of life in patients with shortened dental arches: a multicentre study K. FUEKI*, Y. IGARASHI*, Y. MAEDA † , K. BABA ‡ , K. KOYANO § , K. SASAKI ¶ , Y. AKAGAWA**, T. KUBOKI †† , S. KASUGAI ‡‡ & N. R. GARRETT §§ *Removable Partial Prosthodontics, Tokyo Medical and Dental University, Tokyo, † Prosthodontics, Gerodontolgy and Oral Rehabilitation, Osaka University, Suita, ‡ Department of Prosthodontics, Showa University School of Dentistry, Tokyo, § Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, ¶ Division of Advanced Prosthetic Dentistry, Gradu- ate School of Dentistry, Tohoku University, Sendai, **Department of Prosthodontics, Ohu University, Koriyama, †† Department of Oral and Maxillofacial Rehabilitation, Okayama University Graduate School of Medicine and Dentistry, Okayama, ‡‡ Oral Implantology and Regener- ative Dental Medicine, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan and §§ Division of Advanced Prosthodontics and The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA, USA SUMMARY The aim of this multicentre prospective study was to investigate the effect of prosthetic restoration for missing posterior teeth in patients with shortened dental arches (SDAs). SDA patients with 2–12 missing occlusal units (a pair of occluding premolars corresponds to one unit, and a pair of occluding molars corresponds to two units) were consecutively recruited from seven university-based dental hospitals in Japan. Patients chose no replacement of missing teeth or prosthetic treatment with removable partial dentures (RPDs) or implant-supported fixed partial dentures (IFPDs). Oral health-related quality of life (OHRQoL) was measured using the oral health impact profile (Japanese version – OHIP-J) at baseline and follow-up/post-treatment evaluation. Of the 169 subjects who completed baseline evaluation, 125 subjects (mean age; 63Á0 years) received follow-up/post-treatment evaluation. No-treatment was chosen by 42% (53/ 125) of the subjects, and 58% (72/125) chose treatment with a RPD (n = 53) or an IFPD (n = 19). In the no-treatment (NT) group, the mean OHIP summary score at baseline was similar to that at follow-up evaluation (P = 0Á69). In the treatment (TRT) group, the mean OHIP summary score decreased significantly after the RPD treatment (P = 0Á002), and it tended to decrease, though not statistically significant (P = 0Á18), after the IFPD treatment. The restoration of one occlusal unit was associated with a 1Á2-point decrease in OHIP summary score (P = 0Á034). These results suggest that the replacement of missing posterior teeth with RPDs or IFPDs improved OHRQoL. Prosthetic restoration for SDAs may benefit OHRQoL in patients needing replacement of missing posterior teeth. KEYWORDS: shortened dental arch, removable partial denture, implant-supported fixed partial denture, OHRQoL Accepted for publication 7 March 2015 © 2015 John Wiley & Sons Ltd doi: 10.1111/joor.12297 Journal of Oral Rehabilitation 2015 42; 701--708 Journal of Oral Rehabilitation