| Objective:In this study,we used CBCT to study the age-related changes of alveolar height of the maxillary canine in healthy people,to provide theoretical basis for the development and prevention of periodontal disease.By applying the method of three dimensional reconstruction,to establish a digital model of residual root after alveolar bone height resorption in different age groups,to provide a new idea for the study of the relationship between the of alveolar bone height resorption and the support area of the residual periodontal ligament and support the volume of alveolar,and to provide help for the choice of abutment teeth.Methods:1.CBCT study of maxillary canine alveolar bone height for age-related changes In this study,200 cases CBCT image data of maxillary canine of above 20 years old(inclusive)who is healthy are collected.The cases are divided into five groups(20-29,30-39,40-49,50-59,≥60).Using CBCT image analysis software invivo5.0 system to measure maxillary canine alveolar bone resorption in different ages and different sites(labial,lingual,mesial and distal),the distance of the alveolar bone crest to cemento-enamel junction.Statistical analysis of measurement data using SPSS 21.0,and evaluate the age-related of alveolar bone height and its relationship with gender.2.Three-dimensional measurement of periodontal support of maxillary canine In this study,25 maxillary canines were selected for CBCT scanning.And import image data into mimics software for three-dimensional reconstruction.By the gray characteristics of enamel and cementum,the tooth is divided into two parts of crown and root.Measure the surface area and volume of the crown and root.And by simulating the digital model of the residual root after alveolar bone absorption in different sites of different age groups to measure the residual root surface area and root volume.Statistical analysis of measurement data using SPSS 21.0,and evaluate the relationship between maxillary canine alveolar resorption and the support area of periodontal ligament and support volume of alveolar.Results:1.In the 200 study samples,the measurement data were analyzed,the age significantly affects the absorption of alveolar bone height of four sites(labial,lingual,mesial and distal)of maxillary canine(P<0.05);The height absorption of different sites are different,the labial of maxillary canines is higher than others(P<0.05),the mesial and distal have no obvious difference(P>0.05);The height absorption of alveolar bone in the age group above 50 years was affected by gender,the female was higher than that of male(P<0.05).2.The average tooth area of maxillary canines is 487.17±71.91mm2,the crown surface area is 200.63±23.73 mm2,and the area of crown is286.56±59.33mm2;Average molar volume of maxillary canine is 586.76± 101.33mm3,the crown volume is 270.99±46.11mm3 and the root volume is 316.17±72.07mm3.The area of residual estimation and root volume decreased with age(P<0.05);The remaining root volume of the age over 50 is reduced to less than 80%;The remaining root surface area of the age over 60 is reduced to less than 80%.Conclusions:1.The height of maxillary canine alveolar bone in healthy population has significantly age-related changes,the alveolar height of the labial is significantly higher than that of the other sites,above 50 years old the alveolar bone height resorption is affected by gender.2.CBCT can clearly and accurately display the age-related changes of alveolar bone state,which can provide a theoretical basis for the prevention and development of periodontal disease.3.With the increase of alveolar bone resorption,it decreased ability of periodontal tissue to support.4.CBCT combined with mimics computer software to measure the area and volume of the abutment is worth recommending,and can provide some data support for the selection of the abutment. |
PDF Full Text Request