Changes in PGE2 signaling after submandibulectomy alter post-tooth extraction socket healing

Area of Science:

• Oral biology
• Bone metabolism
• Inflammation research

Background:

• Saliva is crucial for oral health; salivary deficits cause significant oral problems.
• Mechanisms of salivary gland involvement in tooth extraction socket healing are poorly understood.

Purpose of the Study:

• To investigate the effect of submandibulectomy (SMx) on PGE2 signaling and bone regulatory molecules during tooth extraction socket healing.
• To evaluate SMx's impact on inflammation, bone metabolism, and biomechanical properties post-extraction.

Main Methods:

• Submandibular and sublingual glands (SMG and SLG) were ablated in Wistar rats (SMx group).
• Control rats underwent sham surgery.
• Bilateral mandibular molar extraction was performed one week later.
• Socket healing was assessed at 7, 14, and 30 days, measuring inflammation (TNFα, PGE2, COX-II), bone metabolism (OPG, RANKL mRNA), and bone biomechanics.

Main Results:

• SMx significantly increased TNFα, PGE2, and COX-II expression in tooth sockets.
• PGE2 receptor mRNA expression was altered by SMx.
• Osteoprotegerin (OPG) and RANKL mRNA levels were not significantly changed.
• SMx resulted in increased bone mass density and improved structural and mechanical bone properties in the mandibular socket.

Conclusions:

• The submandibular and sublingual glands (SMG/SLG) complex modulates tooth extraction socket repair.
• PGE2 signaling is a key pathway regulated by salivary glands in bone healing.
• SMx promotes enhanced bone density and resistance during socket regeneration.