The effect of inter-implant distance on the height of
inter-implant bone crest.
Tarnow DP, Cho SC, Wallace SS.
Department of Implant Dentistry, New York University College of Dentistry, New
York, USA.
BACKGROUND: The biologic width around implants has been well documented in
the literature. Once an implant is uncovered, vertical bone loss of 1.5 to 2 mm is
evidenced apical to the newly established implant-abutment interface. The purpose of
this study was to evaluate the lateral dimension of the bone loss at the implant-
abutment interface and to determine if this lateral dimension has an effect on the
height of the crest of bone between adjacent implants separated by different distances.
METHODS: Radiographic measurements were taken in 36 patients who had 2
adjacent implants present. Lateral bone loss was measured from the crest of bone to
the implant surface. In addition, the crestal bone loss was also measured from a line
drawn between the tops of the adjacent implants. The data were divided into 2 groups,
based on the inter-implant distance at the implant shoulder. RESULTS: The results
demonstrated that the lateral bone loss was 1.34 mm from the mesial implant shoulder
and 1.40 mm from the distal implant shoulder between the adjacent implants. In
addition, the crestal bone loss for implants with a greater than 3 mm distance between
them was 0.45 mm, while the implants that had a distance of 3 mm or less between
them had a crestal bone loss of 1.04 mm. CONCLUSIONS: This study demonstrates
that there is a lateral component to the bone loss around implants in addition to the
more commonly discussed vertical component. The clinical significance of this
phenomenon is that the increased crestal bone loss would result in an increase in the
distance between the base of the contact point of the adjacent crowns and the crest of
bone. This could determine whether the papilla was present or absent between 2
implants as has previously been reported between 2 teeth. Selective utilization of
implant