Résumé
Abstract Objective This study aimed to validate the integrated correlation between the buccal bone and gingival thickness of the anterior maxilla, and to gain insight into the reference plane selection when measuring these two tissues before treatment with implants. Methodology Cone beam computed tomography (CBCT) and model scans of 350 human subjects were registered in the coDiagnostiX software to obtain sagittal maxillary incisor sections. The buccal bone thickness was measured at the coronal (2, 4, and 6 mm apical to the cementoenamel junction [CEJ]) and apical (0, 2, and 4 mm coronal to the apex plane) regions. The buccal gingival thickness was measured at the supra-CEJ (0, 1mm coronal to the CEJ) and sub-CEJ regions (1, 2, 4, and 6 mm apical to the CEJ). Canonical correlation analysis was performed for intergroup correlation analysis and investigation of key parameters. Results The mean thicknesses of the buccal bone and gingiva at different levels were 0.64~1.88 mm and 0.66~1.37 mm, respectively. There was a strong intergroup canonical correlation between the thickness of the buccal bone and that of the gingiva (r=0.837). The thickness of the buccal bone and gingiva at 2 mm apical to the CEJ are the most important indices with the highest canonical correlation coefficient and loadings. The most and least prevalent subgroups were the thin bone and thick gingiva group (accounting for 47.6%) and the thick bone and thick gingiva group (accounting for 8.6%). Conclusion Within the limitations of this retrospective study, the thickness of the buccal bone is significantly correlated with that of the buccal gingiva, and the 2 mm region apical to the CEJ is a vital plane for quantifying the thickness of these two tissues
Résumé
Objective@# To explore the cause and preventive measures of floor-of-mouth hematoma after dental implant placement. @*Methods@#The prevention of hematoma of the floor of the mouth in a case of lower anterior teeth implant placement was analyzed, and the literature was reviewed.@*Results@# Four mandibular vascular canals were found on the lingual side of the anterior mandible before dental surgery in the reported case. Two of them were quite thick (1.4 mm and 1.0 mm, respectively) and were located adjacent to the crest of the alveolar bone and superior to the mental spine. These two thick endosseous branches from the sublingual artery were dissected and ligated , and there was no obvious hematoma in the patients immediately after the operation and at the postoperative 3 d review. The results of the literature review show that the incidence of endosseous branches from the lingual vascular canal of the mandible is 90%-100%. The distribution of the vessels on the lingual side of the mandible is highly variable and adjacent to the lingual cortical plate. Accidental injury of the lingual cortical plate during implant surgery would probably lead to bleeding or hematoma on the floor of the mouth. @*Conclusion @#Mastering the anatomy of blood vessels on the floor of the mouth, elaboratively examining preoperative three-dimensional radiographic imaging, and cautiously exploring the lower jaw bone morphology after flap elevation are preventive measures to avoid damage to the arterial supply on the lingual side of the anterior lower jaw and to prevent complications of hematoma in the floor of the mouth.