Which statement best distinguishes vertical bone loss from horizontal bone loss?

• A. Vertical bone loss forms angular defects and is more severe on the affected tooth; horizontal is generally uniform
• B. Horizontal bone loss forms angular defects and is more severe
• C. Both patterns are identical
• D. Vertical bone loss is limited to maxillary teeth

Answer: (A)

Vertical bone loss creates angular, wedge- or trench-like defects that are typically localized and can be more severe on the affected tooth. This pattern shows a notable angle between the remaining crest and the root surface, reflecting uneven resorption around the tooth. Horizontal bone loss, by contrast, progresses as a uniform reduction in bone height around the teeth, with no discrete angular defects and the crest remaining at a similar level across neighboring teeth. That contrast—angular, localized defects versus uniform, generalized loss—is what best distinguishes vertical from horizontal bone loss. The other statements don’t fit because horizontal loss does not form angular defects, patterns aren’t identical, and vertical loss isn’t limited to any one arch.