Ridge width gain with screw spreaders: a cadaver study
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Published on: May 31, 2017
Hsun-Liang Chan1, Jia-Hui Fu, Tapan Koticha
1*Clinical Adjunct Assistant Professor, Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI. †Assistant Professor, Department of Preventive Dentistry (Periodontology) at the Faculty of Dentistry, National University of Singapore, Singapore. ‡Resident, Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI. §Clinical Assistant Professor, Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI. ‖Professor and Director, Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI.
Background:
The aim of this cadaver study was to evaluate the amount of ridge expansion with screw spreaders.
Methods:
Eleven edentulous maxillae providing 20 eligible sites were used. Ridges with initial width of 3 to 6 mm were expanded using a set of 6 screw spreaders, and implants (ø3.7 × 10 mm) were subsequently placed. Ridge width at 2 mm apical to the crest was measured at the baseline, after expansion, and implant placement. Buccal plate thickness and incidence of buccal dehiscence after implant placement were measured.
Results:
The mean initial ridge width was 3.97 ± 0.82 mm. After the expansion, the mean ridge width increased to 4.76 ± 0.77 mm (Δ = 0.79 mm). Majority of sites (7/9 sites) with an initial ridge width of <4 mm had a buccal dehiscence after implant placement. A buccal plate thickness of ≥1 mm was consistently present in cases with an initial ridge width of ≥4.5 mm after implant placement.
Conclusions:
The screw spreaders had a modest effect on ridge expansion. Their use might be limited because additional bone augmentation might be required to prevent or correct the bony dehiscence encountered in ridges <4.5 mm wide. Therefore, using this particular instrument kit for horizontal ridge augmentation is only indicated in specific cases.
