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Published on: February 10, 2014
Implant Stability Changes for Nonsubmerged and Submerged Protocols for a Single Implant Mandibular Overdenture Using
Ahmed Salah1, Karim Foda1, Mohamed Farouk Abdalla1
1Prosthodontics Department, Faculty of Dentistry, Cairo University, Giza, Egypt.
Objectives:
To compare the changes in implant stability for the nonsubmerged (NS) and submerged (S) protocols for the single implant retained mandibular overdenture using ball attachment throughout a 24-month follow-up.
Materials And Methods:
Eighty completely edentulous patients were seeking to improve retention of their lower complete denture by installing a single implant in the midline of the completely edentulous mandible. At the day of implant installation, patients were randomized into 2 groups using sealed envelopes: the nonsubmerged (NS) and submerged (S) group. After a 3-month healing period, all patients were randomized using sealed envelopes into ball attachment and CM-LOC attachment. The Periotest readings (PTV) was recorded using the Periotest M device and was recorded every 3 months for the first year and then annually in the second year. The scope of this clinical trial focused only on results of the ball attachment. The Mann-Whitney U test was used for comparison between study groups for independent samples. Two-sided p values less than 0.05 was considered statistically significant.
Results:
There was no statistically significant difference in the mean change in PTV reading between the NS and S group at the different follow-up intervals. Initially, at the day of pickup (baseline) and 3-month follow-up, the mean PTV reading for the NS was greater than that of the S group (-4.471 ± 1.489, -4.391 ± 1.4727 (p=0.913)), while the S group has shown a greater improvement in PTV than the NS group after 6-month follow-up and continued throughout the 24-month follow-up (-5.730 ± 1.7804, -50855 ± 1.2581 (p=1)).
Conclusion:
Both the nonsubmerged and the submerged healing protocol have shown reliable Periotest readings using ball attachment for a single implant retained overdenture. The submerged group has resulted in a greater improvement in Periotest readings after the 12- and 24-month follow-up period when compared to the nonsubmerged group although this improvement was not statistically significant.
