Normal masticatory function partially protects the rat mandibular bone from estrogen-deficiency induced osteoporosis

Area of Science:

• Bone biology
• Skeletal physiology
• Estrogen deficiency effects

Background:

• Mandibular alveolar bone is less sensitive to estrogen deficiency than tibial bone.
• Mechanical loading from mastication may protect alveolar bone.
• Estrogen deficiency negatively impacts bone micro-architecture.

Purpose of the Study:

• To test if mechanical loading protects mandibular bone from estrogen deficiency.
• To compare ovariectomy effects on mandibular and tibial bone in rats fed hard vs. soft diets.

Main Methods:

• Ovariectomy (OVX) or sham surgery in rats.
• Feeding hard (pellets) or soft (porridge) diets.
• Micro-computed tomography for bone micro-architecture analysis.
• Statistical analysis of ovariectomy and diet effects.

Main Results:

• Ovariectomy negatively affected tibial bone and mandibular bone (trabecular number/spacing).
• A soft diet further decreased mandibular bone volume, thickness, and number, increasing separation.
• Significant interaction between ovariectomy and soft diet on mandibular bone parameters observed.

Conclusions:

• A normal (hard) diet significantly limited negative effects of estrogen deficiency on mandibular bone micro-architecture.
• Mastication's mechanical loading may play a protective role in mandibular bone health post-ovariectomy.