title: Primary Stability of a Hybrid Implant Compared with Tapered and Cylindrical Implants in an Ex Vivo Model.
abstract: BACKGROUND
  Hybrid implants are thought to offer good stability and bone-implant contact.
  
  
  OBJECTIVE
  This study sought to evaluate the primary stability of a hybrid implant compared with tapered and cylindrical implants in an ex vivo model and compare undersized drilling with standard drilling in attaining primary stability.
  
  
  METHODS
  Hybrid (Straumann® Bone Level; BL), tapered (Straumann® Tapered Effect; TE), and cylindrical (Straumann® Standard Plus; SP) implants were inserted into 15 mm-thick porcine iliac crest blocks using standard (corticocancellous or cancellous bone) or undersized (cancellous bone only) drilling (n = 7). Stability was evaluated using maximum insertion torque (MIT), implant stability quotient (ISQ), and push-out tests.
  
  
  RESULTS
  The mean MIT for BL and TE was significantly higher than that for SP (p < 0.05). With standard drilling in corticocancellous bone, the mean ISQ for TE was significantly higher than that for SP (p < .05). The mean MIT, ISQ, and push-out test scores for BL, TE, and SP with standard drilling in corticocancellous bone were significantly higher than those with undersized or standard drilling in cancellous bone (p < .05).
  
  
  CONCLUSIONS
  In this ex vivo model, the hybrid implant demonstrated promising primary stability compared with the cylindrical implant. The improved stability of the hybrid implant was especially evident in cancellous bone. The influence of the cortical layer should be recognized when selecting implants for primary stability.
authors: Division of Maxillofacial Diagnostic & Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Takeshi
authors: T
authors: Toyoshima
authors: Division of Maxillofacial Diagnostic & Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hideaki
authors: H
authors: Tanaka
authors: Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Yasunori
authors: Y
authors: Ayukawa
authors: Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Miori
authors: M
authors: Howashi
authors: Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Tomohiro
authors: T
authors: Masuzaki
authors: Division of Maxillofacial Diagnostic & Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.|Regenerative Dentistry and Implant Center, Kyushu University, Fukuoka, Japan.
authors: Takahiro
authors: T
authors: Kiyosue
authors: Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.|Regenerative Dentistry and Implant Center, Kyushu University, Fukuoka, Japan.
authors: Kiyoshi
authors: K
authors: Koyano
authors: Division of Maxillofacial Diagnostic & Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Seiji
authors: S
authors: Nakamura
mesh_terms: D000818:Animals; D015519:Bone Density; D015921:Dental Implants; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D007085:Ilium / Q000502:physiology; D013499:Surface Properties; D013552:Swine; D019415:Torque
chemical_list: D015921:Dental Implants
keywords: animal model; dental implant; implant stability quotient; maximum insertion torque; primary stability; push-out test