Effects Of Inferior Alveolar Never Transection On Peri-implant Trabecular Structures:a Cone Beam CT Evaluation

Purpose: To develop a method for characterizing trabecular bone microarchitecture using cone beam computed tomography(CBCT) and to evaluate trabecular bone changes after inferior alveolar nerve(IAN) section.Materials and Methods: Six healthy mongrel dogs unilateral inferior nerves were sectioned.2 weeks later,after model construction,the premolars of denervated side and normal side were extracted and randomly received 22 titanium implants in the mandibular premolar areas.The normal sides were used as comparison.The animals were euthanized at 8 weeks, and block biopsies were scanned using high resolution Cone Beam CT. Standard bone structural variables were assessed in coronal, middle,and apical levels.The bone volume fraction(BV/TV:%), specific bone surface(BS/BV:mm2/mm3), Trabecular thickness(Tb.Th:mm),trabecular separation(T b. S p : m m), t r a b e c u l a r n u m b e r(T b. N : 1 / m m), b o n e p a t t e r n fa c t o r(Tb.pf:1/mm),structural model index(SMI), fractal dimension(FD), total porosity percentage(po(tot):%),connectivity density(Conn.dn:1/mm3) from the region of interest were analyzad by the CTan software.Results:Coronal and middle regions had more compact, more platelike, and thicker trabeculae. Denervation groups had significantly higher values(p<0.05) than control groups for bone volume fraction(BV/TV:%),while significantly lower values(p < 0.05)were found for bone surface volume ratio(BS/BV:mm2/mm3), trabecular separation(Tb.Sp:mm), total porosity percentage(po(tot):%) and connectivity density(Conn.dn:1/mm3).Conclusion:Cone Beam CT can analyse peri-implant trabecular microstrutural effectively; Coronal region had more compact, more platelike, and thicker trabeculae;Compared with control groups,Inferior Alveolar Nerve absence has affection on the bone structure remodeling.