How to create a 3D volume with overlapping slices?

HI, I have around 100 slices of slice thickness 2.5 mm with a spacing of 1.5 mm. So, the slices are overlapping. I want to create a 3D model from the stack of slices. I have an stl generating program but I don't know if I can give the stack of slices I have as they have an overlap.

    for count = 1:totalSlices
      fileName = dirData(count).name;
      dicomImage = dicomread(fileName);
      imageStack(:,:,count) = dicomImage;
    end

And I used the ExportVoxelData function from Matlab central to generate an stl file from the image stack above

I do have an stl model but I do not know if it is scaled correctly in the z direction My pixel dimensions are 0.9766 mm in X and Y dimensions. My slice thickness is 2.5 mm My slice spacing is 1.5 mm

If the slice thickness is less than the spacing between slices, then there is a gap region between the slices that was not imaged. If the slice thickness is greater than the spacing between slices, then the slices overlap (there exists a region that contributed information to both of the adjacent slices). So the overlap in my slices is 2.5-1.5 = 1 mm. The problem is I dont know how to account for this overlap when I am making a 3D model