Influence of marginal bone resorption on two mini implant-retained mandibular overdenture: An in vitro study

Abstract

PURPOSE To investigate the biomechanical effect of marginal bone resorption (MBR) on the mandibular mini implant (MI)-retained overdenture (MI-OD) on the edentulous model. MATERIALS AND METHODS The experimental mandibular edentulous model was modified from a commercial model with 2 mm thick artificial soft tissue under denture base. Two MIs (Φ2.6 mm × 10 mm) were bilaterally placed between the lateral incisor and the canine area and attached with magnetic attachments. Three groups were set up as follows: 1) alveolar bone around the MI without MBR (normal group), 2) with MBR to 1/2 the length of the implant (resorption group), and 3) complete denture (CD) without MI (CD group). Strain around the MI, pressure near the first molar area, and displacement of denture were simultaneously measured, loading up to 50 N under bilateral/unilateral loading. Statistical analysis was performed using independent-samples t test and one-way ANOVA (α=.05). RESULTS The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure in CD was higher than in MI-ODs ( P <.05), while there was no statistical difference between the normal and resorption group ( P >.05). Similarly, the CD demonstrated a greater displacement of the denture base than did the MI-ODs during bilateral and unilateral loadings ( P <.05). CONCLUSION The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure on posterior alveolar ridge and denture displacement of MI-ODs significantly decreased compared to CDs, even when MBR occurs. Bilateral balanced occlusion was recommended for MI-ODs, especially when MBR occurred.

Influence of Implant Number on Peri-Implant and Posterior Edentulous Area Strains in Mandibular Overdentures Retained by the New Ti–Zr (Roxolid®) Mini-Implants as Single-Units: In Vitro Study

“…Insertion of two MDIs showed good survival rates and low amounts of marginal bone loss only when used for retention of removable partial dentures [16][17][18]. However, the clinical outcomes of only two MDIs retaining a complete mandibular OD are still doubtful [19][20][21][22]. To the best of our knowledge, no longitudinal clinical reports are available when only one MDI, inserted in the midline of the mandible, was used for the retention of a complete OD.…”

Peri-implant marginal bone loss and oral health-related quality of life in patients treated by mini-implant-retained mandibular overdentures with different occlusal schemes (lingualized, monoplane and bilateral balanced): A randomized clinical trial

“…The usage of mini implant to support an overdenture has become increasingly accepted and advocated owing to their reduced diameter enabling practitioners to insert them in narrow alveolar ridges with less complex surgical techniques lowering postoperative morbidity, speeding up healing process and increasing patient's acceptance 10 . Recent guidelines support the insertion of four mini implants to support a mandibular overdenture 30 . Most research work is directed at standard diameter implants, there is relative knowledge insufficiency about clinical performance of mini implants, surrounding bone, esthetic expectations, patient's biting force and appropriate occlusal scheme.…”

Accuracy of Proximal and Occlusal Contacts of Single Implant Crowns Fabricated Using Different Digital Scan Methods: An In Vitro Study

“…The accuracy of the desktop scanner used in the present study was calibrated before the experiment, and the scanning accuracy of less than 10 µm was verified by the manufacturer. The present study evaluated the contact accuracy of the implant prosthesis manufactured by each group, but the previous study evaluated the strain around implant [ 33 ]. The implant prosthesis should be passively connected to the implant for a good long-term prognosis, so that less strain around implants should be given [ 33 ].…”

“…The present study evaluated the contact accuracy of the implant prosthesis manufactured by each group, but the previous study evaluated the strain around implant [ 33 ]. The implant prosthesis should be passively connected to the implant for a good long-term prognosis, so that less strain around implants should be given [ 33 ]. The reason for evaluating the contact accuracy of the implant prosthesis in the present study is that the contact accuracy can affect the strain around implant.…”