This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
What histologic criteria is used to distinguish gingivitis from periodontitis 
Select and explain. 
A. Occlusal trauma, B. Howships lacunae, C. Bone Resorption, D. Endosteal Proliferation
B: Howships lacunae
Answer: B: Howships lacunae 
Explanation: None