ABSTRACT
Objective@#To investigate the prevalence of bifid mandibular canals (BMC), and to measure their diameter and angle. @*Methods @#CBCT images of 500 patients were used for this study. The incidence and types of bifid mandibular canals were recorded according to a modified classification of Naitoh: Ⅰ, retromolar canal; Ⅱ, dental canal; Ⅲ, forward canal; Ⅳ buccolingual canal. The diameter and angle between the accessory canal and the main mandibular canal were recorded.@*Results@#Bifid mandibular canals were found in 32.2% of the 1 000 hemi- mandibles, with the incidence rate of 52.17%, 36.02%, 6.21%, 5.59% in TypeⅠ, Ⅱ, Ⅲ, Ⅳ respectively. There are 90 cases of the mandibular branch with a diameter greater than or equal to the backbone 1/2, and 100 cases that are less than 1/2 of the backbone. The angle between the mandibular branch and the trunk Ⅰ, Ⅱ and Ⅲ were 50.21° ± 22.25°、28.81° ± 11.5° and 13.50° ± 2.39° respectively. @*Conclusion @#Bifid mandibular canals were observed at a relatively high incidence using CBCT, and the most common type was the retromolar canal. It is suggested CBCT should be taken before mandibular surgery to give an accurate evaluation of bifid mandibular canals.
ABSTRACT
Objective@# To investigate the prevalence of bifid mandibular canals (BMC), and to measure their diameter and angle.@*Methods @# CBCT images of 500 patients were used for this study. The incidence and types of bifid mandibular canals were recorded according to a modified classification of Naitoh: Ⅰ, retromolar canal; Ⅱ, dental canal; Ⅲ, forward canal; Ⅳ buccolingual canal. The diameter and angle between the accessory canal and the main mandibular canal were recorded. @*Results @#Bifid mandibular canals were found in 32.2% of the 1 000 hemi- mandibles, with the incidence rate of 52.17%, 36.02%, 6.21%, 5.59% in TypeⅠ, Ⅱ, Ⅲ, Ⅳ respectively. There are 90 cases of the mandibular branch with a diameter greater than or equal to the backbone 1/2, and 100 cases that are less than 1/2 of the backbone. The angle between the mandibular branch and the trunk Ⅰ, Ⅱ and Ⅲ were 50.21° ± 22.25°、28.81° ± 11.5° and 13.50° ± 2.39° respectively. @*Conclusion@#Bifid mandibular canals were observed at a relatively high incidence using CBCT, and the most common type was the retromolar canal. It is suggested CBCT should be taken before mandibular surgery to give an accurate evaluation of bifid mandibular canals.
ABSTRACT
@#With the increasing development of digital technologies, digital surgical templates have been widely used in stomatology. However, the accuracy of digital surgical templates is always a consideration for many researchers and dentists. This article analyzed the factors affecting the accuracy of digital surgical templates and found that errors arise from six factors, including the design and manufacture of the templates, implant guide support, implant systems and guide systems, implant length, bone density and the clinical experience of the operator; this literature review aims to reduce or eliminate human factors and improve accuracy, objectivity and security in implant placement.
ABSTRACT
Objective @#To describe a novel workflow for the anterior dental esthetics in immediate implant and immediate aesthetic restoration with digital technique. @*Methods @#Before the implant placement, a intra-oral optical scan(IOS) combined with CBCT was performed to virtually design the 3D implant position and restoration. A surgical guide and an individualized Ti abutment restoration was CAD/CAM-fabricated out of the PMMA-based in a fully digital workflow and seated at the stage of minimal invasive surgery.@*Results @#The technique achieved immediate implant and immediate restoration after tooth extraction. Immediate restoration of temporary crown could be completed immediately in second patient visit after the operation, finally realized the aesthetic implantation with preserved soft tissue contour. @*Conclusin @# The fully digital technique changed the conventional workflow which achieves more efficiency and better aesthetic effect.