|Baltic Dental and Maxillofacial Journal|
September, 2004, Vol. 6, No. 3
© 2004 Stomatologija
Stomatologija 2004; 6 (3): 85-90 847 KB
Retentive and Stabilizing Properties of Stud and Magnetic Attachments Retaining Mandibular Overdenture. An in vitro Study
Vygandas Rutkunas, Hiroshi Mizutani
Objectives: To evaluate and compare retentive and stabilizing properties of stud (ERA Overdenture (orange and white), Locator Root (pink) and OP anchor # 4) and magnetic attachments (Hyperslim 4513, Hyperslim 4013, Magfit EX600W, Magnedisc 500 and Magfit-RK) by measuring maximum retentive force and retentive energy during linear and rotational dislodgments.
Material and methods: Twelve specimens of each type of attachment were used. Linear and 3 types of rotational (anterior, lateral and posterior) dislodgements were performed on one-tooth and mandible-overdenture models, respectively. For each type of dislodgement10 measurements were recorded by universal testing machine (AGS-H, Shimadzu Co., Kyoto, Japan) with 50 mm/min cross head speed. Statistical analysis: one-way ANOVA and Scheffe post-hoc tests (P<0.05).
Results: Studs provided higher retention and stability than magnetic attachments. As for rotational dislodgements maximum retentive force of magnetic attachments decreased in following order anterior > lateral > posterior; whereas of studs posterior > anterior > lateral. Magnetic attachments had considerably lower retentive energy values for all types of dislodgements.
Conclusions: Retentive properties depend on types of attachment and dislodgment. Stud attachments provide stronger retentive and stabilizing forces than magnetic attachments with all types of dislodgements. Constant retentive properties and low retentive energy of magnetic attachments could assist abutment preservation. Further studies are necessary to clarify range of retention and fatigue behavior of overdenture attachments. Attachments with proper retentive and stabilizing properties should be selected in particular clinical situation.
Key words: overdenture, studs, magnets, retention, stability.
Received: 02 09 2004
Accepted for publishing: 20 09 2004
Vygandas Rutkunas - D.D.S., Center of Prosthodontics, Institute of Odontology, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
Hiroshi Mizutani - D.D.S., PhD, Department of removable prosthodontics, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
Address correspondence to Vygandas Rutkunas, Zalgirio str. 115, 08217 Vilnius, Lithuania. E-mail: email@example.com