Substance P enhances the inhibition of osteoblastic cell differentiation induced by lipopolysaccharide from Porphyromonas gingivalis.

Background: Substance P (SP) is a multifunctional neuropeptide that transmits pain signals, regulates the immune system, and may modulate emotional stress. SP stimulates bone resorption activity of osteoclasts, and SP level in gingival crevicular fluid is correlated with the degree of periodontal inflammation. However, the exact roles of SP in bone metabolism and periodontal diseases are poorly understood.

Pronounced Palatal and Mandibular Tori Observed in Patient With Chronic Phenytoin Therapy: A Case Report.

Phenytoin, an anticonvulsant drug for epileptic patients, has many adverse effects, including calvarial thickening and coarsening of the facial features. Previous studies have demonstrated that phenytoin has an anabolic action on bone cells. This report describes pronounced palatal and mandibular tori found in a 45-year-old Japanese man undergoing chronic phenytoin therapy.