THE EFFECT OF MAGNETIC AND CM LOCK ATTACHMENTS ON STRAIN AROUND IMPLANTS RETAINED MANDIBULAR OVERDENTURE: A STRESS ANALY SIS STUDY

Objectives: This in-vitro strain gauge study was conducted to compare between magnetic and
CM lock attachments regarding strain induced around two implants supporting a mandibular over
denture.
Methodology: This study was performed using two implants 3.7mm x 12mm installed at the
canine area bilaterally in an acrylic model resembling a completely edentulous mandible. Pick
up of the magnetic and CM loc attachments was done followed by loading and measurements
respectively. The strain induced around the implants was evaluated during unilateral and bilateral
loading at the first molar area using a universal testing machine. Measurements were tabulated and
statistically analyzed.
Results: loading sides demonstrated significantly higher microstrains around the implants with
the two attachments than non-loading sides. CM LOC attachment showed significantly higher
microstrains than magnetic attachment for both loading and non-loading sides during unilateral
loading. During bilateral loading, a statistically significant higher mean micro strain was recorded
in the right implant than the left implant, CM lOC have shown a higher statistically significant mean
micro strain than the magnetic attachment for the right implant and no siginificant difference in the
left implant.
Conclusions: Within the limitation of this in-vitro study, it could be conclude that the attachment
type could have an effect on the amount of load that will be transmitted to the implants supporting
an over denture. Clinical studies are required to evaluate the effect of type of attachment on peri
implant crestal alveolar bone loss and correlate it with the results of the current study.