implant-supported prosthesis, immediate loading, narrow implants, overdenture


The aim of this study was to evaluate the primary and secondary stability and success rates of narrow and extra-narrow implants as retainers’ mandibular overdentures. Twelve fully edentulous mandible patients participated of this split-mouth randomized controlled clinical trial. One narrow (G1: 3.5-mm) and one extra-narrow implant (G2: 2.9-mm) were placed in each patient. Data regarding anesthetics use, incision size, number of drills used, and surgery duration were obtained. Moreover, a satisfaction VAS (visual analog scale) questionnaire was answered by the surgeon to evaluate clinician satisfaction with respect to characteristics of the surgical procedure. The implants stability quotient (ISQ) was measured immediately after the implants placement (T0) and after four months of the surgical procedure (T4). Additionally, the success rates of the implants during the osseointegration period were recorded. Regarding the characteristics of the surgical technique, statistically significant difference between groups was found for incision length - which was significantly smaller for group G2 - and insertion torque - which was significantly greater for group G1 (P-value = 0.025 and 0.005, respectively). There was no statistically significant difference for ISQ values between T0 and T4 within the same group (G1, p=0.510 and G2, p=0.116). The implant success rate was 100% for both groups. Therefore, narrow, and extra-narrow implants showed good primary and secondary stability, as well as short-term implant success rates, without statistically significant differences between them, and thus seem to be suitable alternatives to retain immediately loaded mandibular overdentures.


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Author Biographies

Sidney Sato Oku

Student in Faculty ILAPEO, Department of Implantology, Curitiba, PR, Brazil. Master in Dentistry with concentration area in Implantology, Faculty ILAPEO, Curitiba, PR, Brazil.


Elisa Mattias Sartori

Professor in Faculty ILAPEO, Department of Implantology, Curitiba, PR, Brazil. PhD in Dentistry with concentration area in Oral and Maxillofacial Surgery, UNESP Araçatuba, SP, Brazil.

Francine Baldin Able

Professor in Faculty Sete Lagoas, FACSETE, Belo Horizonte, MG, Brazil. PhD in Dentistry with concentration area in Integrated Clinic, UEPG, Ponta Grossa, PR, Brazil.

Fabiano Marcelo Nava

Student in Faculty ILAPEO, Department of Implantology, Faculty ILAPEO, Curitiba, PR, Brazil. Master in Dentistry with concentration area in Implantology, Faculty ILAPEO, Curitiba, PR, Brazil.

Guilherme José Pimentel Lopes Oliveira

Associate Professor, Department opf Periodontology and Implantology, Dentistry School, Federal University of Uberlandia, MG, Brazil. PhD in Dentistry with concentration area in Diagnosis and Surgery, UNESP Araraquara, SP, Brazil.

Ivete Aparecida de Mattias Sartori

Professor in Faculty ILAPEO, Department of Implantology, Curitiba, PR, Brazil. PhD in Oral Rehabilitation, USP Ribeirão Preto, SP, Brazil. 


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How to Cite

Oku, S. S., Mattias Sartori, E., Baldin Able, F., Nava, F. M., Pimentel Lopes Oliveira, G. J., & Mattias Sartori, I. A. de. (2023). NARROW AND EXTRA-NARROW IMPLANTS TO RETAIN MANDIBULAR OVERDENTURES: A SPLIT-MOUTH STUDY. Journal Health and Technology - JHT, 2(1), e2128.