Lingual Cortical Bone Thickness Research Articles

The morphology of alveolar bone of the mandibular second and third molars in skeletal Class III patients.

To investigate the alveolar bone morphology of the mandibular second and third molars in skeletal Class III patients from a buccolingual direction. Sixty skeletal Class III patients were recruited. The alveolar bone width, buccal cortical bone thickness and lingual cortical bone thickness were measured in five planes from mesial to distal and at five depths from gingival to root. The effects of the gender of the patients, the second molar lingual inclination and the third molar on alveolar bone width and cortical bone thickness were evaluated. To explore the effect of third molar extraction on alveolar bone morphology, the measurements before and after third molar extraction were compared. The impacted third molar had significantly greater alveolar bone width and thicker buccal cortical bone at the cervical third of the molar, while the erupted third molar had greater alveolar bone width at the apical third. Three weeks after third molar extraction, these advantages would weaken owing to the reconstruction of the alveolar bone. Patients with lingually inclined molar were observed to own thicker lingual cortical bone. Males tended to have greater alveolar bone width, but no significant differences were shown in this study. The growth of the third molar and the second molar lingual inclination affect the alveolar bone morphology of the mandibular second and third molars significantly, but gender has trivial effects on the morphology. The alveolar bone morphology of the mandibular second and third molars would change 3 weeks after third molar extraction.

Evaluation of the correlation between facial index and the cortical bone thickness of the maxilla and mandible—A computer tomography based study

Objectivescortical bone thickness confines the position of teeth and thus can be a limiting factor for orthodontic tooth movement. The study is aimed to correlate the cortical bone thickness of the maxilla and mandible with that of different face types, viz; dolichofacial, brachyfacial, and mesofacial. MethodsForty CT scans were analysed for the face types and were grouped into dolichofacial (13), brachyfacial (13) and mesofacial (14) face types. The scans were measured for the right and left side buccal and lingual cortical bone thickness at the central incisor, first and second molar regions on both the maxilla and mandible. Other parameters like basal cortical bone thickness, height, and width of cortical bone were also measured. To determine the correlation and difference between the different parameters, the obtained data was subjected to the correlation coefficient, t test, and ANOVA statistical analysis. ResultsMaxillary buccal cortical bone thickness of central incisors was found to be highly correlated to facial index with a correlation coefficient of − 0.833 * *. Mandibular buccal bone thickness correlated with face type and cortical bone thickness at the central incisor, first, and second molars by-0.531 * *, − 0.474 * *, and − 0.589 * *, respectively. There was a significant difference between the right and left side cortical bone thickness (p < 0.05) and also for all the parameters amongst the different face types (p < 0.05). ConclusionThere exists a definite correlation between the face type and the certain anatomical measurements of cortical bone morphology. Dolichofacial face types show thin buccal cortical bone, which implies the limitation of orthodontic tooth movement in these types of individuals.

Optimal Implantation Site of Orthodontic Micro-Screws in the Mandibular Anterior Region Based on CBCT.

Background: To determine the optimal implantation site of orthodontic micro-screws based on cone beam computed tomography (CBCT) analysis in the mandibular anterior tooth region, provide a theoretical basis for orthodontic implant placement and improve post-implantation stability.Methods: Forty patients who underwent CBCT scanning were selected for this study. CBCT scanning was applied to measure the interradicular distance, buccolingual dimension, labial cortical bone thickness and lingual cortical bone thickness between mandibular anterior teeth at planes 2, 4, 6, and 8 mm below the alveolar ridge crest. The data were measured and collected to obtain a comprehensive evaluation of the specific site conditions of the alveolar bone.Results: The interradicular distance, buccolingual dimension and labial cortical bone thickness between the mandibular anterior teeth were positively correlated with the distance below the alveolar ridge crest (below 8 mm). The interradicular distance, buccolingual dimension, labial cortical bone thickness, and lingual cortical bone thickness were all greater than those in other areas between the lateral incisor root and canine incisor root 4, 6, and 8 mm below the alveolar ridge crest.Conclusion: The area between the lateral incisor root and the canine incisor root in planes 4, 6, and 8 mm from the alveolar ridge crest can be used as safe sites for implantation, while 8 mm below the alveolar ridge crest can be the optimal implantation site. An optimal implantation site can be 8 mm below the alveolar ridge crest between the lateral incisor root and the canine incisor root.

Radiological Assessment of Egyptian Mandible Morphometric Parameters Using Cone Beam Computed Tomography (CBCT)

Introduction Accurate appraisal of bone dimensions and morphology is essential for preoperative planning. The present study was conducted to estimate the different morphometric parameters and to determine the mandibular canal and mental foramen location using CBCT. Materials and Methods CBCT imaging of 48 Egyptians was performed. The mandibles were investigated around the 1st molar, for total height (TH), upper distance (UD) , lower distance (LD), total thickness (TT), buccal cortical bone thickness (BCB), lingual cortical bone thickness (LCB) and cancellous bone thickness (CAB), diameter of the mandibular canal (DOM) and gonial angle (GA). Variations in mandible shape and mental foremen sites were also assessed. Results A significant difference between the mean TH in both groups was detected, while the mean UD and LD showed insignificant differences. The mean values of TT and CAB were greater in males however the mean BCB and LCB were greater in females. DOM was greater in males but statistically insignificant. Statistically insignificant differences between the mean GA in females (greater) and males were observed. The TH, LD, TT and CAB, DOM showed positive correlations to the age in both groups however the UD, BCB, LCB and GA showed negative correlations. The commonest position of the mental foramen was opposite the apex of the fifth tooth (54.2%). The shape of the mandible were categorized into type A (83.3%), B (0%), C (10.4%) and straight (6.3%). Conclusion Mandibular measurements and morphology are unique and their assessment by CBCT becomes crucial before any dental implant.

Assessment of the cortical bone thickness by CT-scan and its association with orthodontic implant position in a young adult Eastern Mediterranean population: A cross sectional study

This study was conducted to assess cortical bone thickness in the alveolar process of maxilla and mandible and to investigate its association with different orthodontic implant positions in Eastern Mediterranean young adults. Computed tomography images of 50 patients aged between 18-35 years were included. Buccal, palatal and lingual cortical bone thicknesses were measured at 2, 4, 6, and 8mm from cemento-enamel junction starting from the mesial side of the second molar to the contralateral side. Pearson correlation was used to assess the association between cortical bone thickness and proposed orthodontic implant positions at all inter-radicular sites (p<0.05). The highest value of buccal cortical bone thickness was found mesial to the second molar in the maxilla and mandible for both genders. The value of palatal cortical bone thickness was found to be at the highest rate mesial to canine and first premolar in males and females respectively. On the other hand, the highest value of lingual cortical bone thickness was recorded to be mesial to the first molar in both genders. In addition to that, the buccal cortical bone thickness was significantly higher than palatal at the area mesial to the second molar at all four levels from the cemento-enamel junction. A significant correlation was found between cortical bone thickness and 2, 4, 6, and 8mm orthodontic implant levels in all inter-radicular sites. The values of correlation coefficients ranged from 0.280 to 0.674 in the maxillary arch and from 0.266 to 0.605 in the mandibular arch. From this study, we can conclude that as the position of the orthodontic implant moved more posteriorly and apically more cortical bone thickness was expected to be found in both jaws. A significant correlation was found between cortical bone thickness and the site of the orthodontic implant. Cortical bone thickness and its relationship with implant position should be taken into consideration when attempts are made to insert the orthodontic implant.

Evaluation of lingual cortical bone thickness of the mandibular third molars using CBCT

Evaluation of lingual cortical bone thickness of the mandibular third molars using CBCT

Relationship between alveolar bone thickness, tooth root morphology, and sagittal skeletal pattern : A cone beam computed tomography study.

The goal of this work was to examine the relationship between sagittal facial pattern and thickness of alveolar bone in conjunction with root morphology of teeth by using cone beam computed tomography (CBCT). The study was carried out on the CBCT scans from 3group of patients (n = 20 in each group). The first group involved skeletal class1, the second group involved skeletal class2, and the third group involved skeletal class3 patients. In all, 14permanent teeth and interdental regions in the maxilla and mandible were evaluated. Root length and root width were measured on each tooth. Buccal cortical bone thickness, cancellous bone thickness, and lingual cortical bone thicknesses were measured in each interdental region. Analysis of variance, Kruskall-WallisH and Mann-WhitneyU tests were used for statistical comparisons. No significant difference was found between the groups for root length, root width, buccal cortical bone and lingual cortical bone thickness. A significant difference was observed between the groups for cancellous bone thickness as it was thicker in skeletal class2 group. Cortical bone was thicker in the mandible compared to maxilla on both buccal and lingual sides and it was thicker in the posterior region compared to the anterior region on the buccal side. Differences in cancellous bone thickness between different sagittal facial patterns and differences in cortical bone thickness between different alveolar regions should be taken into consideration when planning orthodontic tooth movements and anchorage mechanics.

Inferior alveolar nerve canal position in relation to mandibular molars: A cone-beam computed tomography study.

Objective:This study was carried out to prevent the risk of iatrogenic injuries to the inferior alveolar nerve (IAN) canal associated with various surgical interventions in the area of mandibular molars, by using cone-beam computed tomography (CBCT).Materials and Methods:The present retrospective study was carried out by using CBCT of 100 patients between 18 and 40 years of age group. The linear measurements were made in relation to the 1st and 2nd mandibular molars on both the sides. Linear distances between buccal and lingual aspects to the mandibular, buccal, and lingual cortical bone thickness; IAN canal diameter; and the superior corticated border of the IAN canal from the periapex of the 1st and 2nd mandibular molars. The statistical evaluation was done using SPSS V.20 (SPSS: an IBM company), and P < 0.05 was considered statistically significant.Results:Both genders of all age groups showed statistically significant result (P < 0.00). All the linear measurements were statistically significant in relation to both the 1st and 2nd mandibular molars (P < 0.005), and also the bilateral comparison of the linear measurements showed statistically significant difference in relation to the mandibular 2nd molar (P < 0.03) and 1st molar (P < 0.04) among both the sexes.Conclusion:Clinicians should be aware of the proximity of root apices and cortical plates to the mandibular canal when performing surgical and root canal procedures in the posterior mandible to avoid serious nerve injuries.

Dentoalveolar Evaluation of Lower Incisors by CBCT after Treatment with Herbst Appliance.

This study aimed to evaluate the effects of the Herbst appliance on the proclination and protrusion of the lower incisors, and to verify if the device causes alveolar bone loss in the anterior region of the mandible. This is a retrospective study. The sample consisted of 35 individuals. The treatment group consisted of 22 individuals (8 girls and 14 boys; initial mean age of 8.2 years) who used the Cantilever Herbst appliance for a period of 12 months. The control group consisted of 13 individuals (3 girls and 10 boys; initial mean age of 8.9 years) who received no treatment and were followed up for a period of approximately 18 months. Cone-beam computed tomography scans were performed at the beginning and at the end of the observational period. The medullary bone thickness (MT), buccal cortical bone thickness (BCT), lingual cortical bone thickness (LCT), and lower incisors proclination and protrusion were evaluated. Data were submitted to statistical analysis (ANCOVA and Student's t-test) with a significance level of 5%. There was no significant difference in MT, BCT, LCT and incisor proclination between groups. Incisor proclination increased in the treated group with no statistical significance. The treatment group showed a significant increase in the protrusion of the incisors (p = 0.02). The Herbst appliance promoted a small proclination and protrusion of the lower incisors, without relevant clinical implications. The Herbst appliance did not cause bone loss in the anterior region of the mandible during Class II treatment.

안면골격 유형에 따른 하악 전치 치조골의 형태 차이: Cone-beam CT를 이용한 정량적 평가

Purpose: The aim of this study was to investigate differences between the morphology of the mandibular symphysis and four facial skeletal types. Materials and Methods: 40 cone-beam computed tomographies were selected and classified in to 4 groups according to their vertical and anterior-posterior skeletal patterns. The bone volume (mm³) of the symphysis, the cross sectional area corresponding to the 4 mandibular incisors’ axis: the cross sectional area of total bone (mm²), the area of the cancellous bone (mm²) and the thickness (mm) of labial and lingual alveolar bone at 2 mm, 3 mm under the cemento-enamel junction (CEJ) were measured. General linear model (GLM), Kruskal-Wallis test and Tukey honestly significant difference (HSD) test were subsequently used for statistical analysis. Results: The lingual cortical bone thickness of the lateral incisors at 2, 3 mm under CEJ was greater in the Class I low angle group than the other 3 groups (P < 0.05). There were no statistically significant differences in the volume of the mandibular incisor bony support, cross-sectional area of total bone and cancellous bone at the mandibular incisor’ axis. Conclusion: Patients in Class I, low angle group have a thicker lingual mandibular symphysis than Class I, high angle patients.

Evaluation of mandibular cortical bone thickness for placement of temporary anchorage devices (TADs)

ObjectiveIn this study, we measured the cortical bone thickness in the mandibular buccal and lingual areas using computed tomography in order to evaluate the suitability of these areas for application of temporary anchorage devices (TADs) and to suggest a clinical guide for TADs.MethodsThe buccal and lingual cortical bone thickness was measured in 15 men and 15 women. Bone thickness was measured 4 mm apical to the interdental cementoenamel junction between the mandibular canine and the 2nd molar using the transaxial slices in computed tomography images.ResultsThe cortical bone in the mandibular buccal and lingual areas was thicker in men than in women. In men, the mandibular lingual cortical bone was thicker than the buccal cortical bone, except between the 1st and 2nd molars on both sides. In women, the mandibular lingual cortical bone was thicker in all regions when compared to the buccal cortical bone. The mandibular buccal cortical bone thickness increased from the canine to the molars. The mandibular lingual cortical bone was thickest between the 1st and 2nd premolars, followed by the areas between the canine and 1st premolar, between the 2nd premolar and 1st molar, and between the 1st molar and 2nd molar.ConclusionsThere is sufficient cortical bone for TAD applications in the mandibular buccal and lingual areas. This provides the basis and guidelines for the clinical use of TADs in the mandibular buccal and lingual areas.

Relationship between facial types and tooth and bone characteristics of the mandible obtained by CT scanning.

The purpose of this study was to evaluate relationships between morphological characteristics of vertical sections of the mandibular body and facial type. Of the correlation coefficients between tooth and bone inclination and facial type parameters, facial height index (FHI) was negatively associated with second premolar (P2), first molar (M1), and second molar (M2) inclinations. The angle represented by Frankfort horizontal plane to mandibular plane (FMA) was negatively associated with bone inclination of the M2 section. The buccal cortical bone was thicker in short-faced individuals than in the average and long-faced groups, while lingual cortical bone thickness of the M1 and M2 sections was greater. The basal cortical bone thickness of the L1 section was greater in the short-faced group, and the inclinations of the P2, M1, and M2 axes were significantly smaller. Teeth in the short-faced group inclined more lingually than in the average- and long-faced groups. The results of this study provide evidence that a significant but complex relationship exists between structures of the mandibular body and facial types. The morphological features that relate to masticatory function and facial types are associated with cortical bone thickness of the mandibular body and the buccolingual inclination of the first and second molars.

Morphological Characteristics of Vertical Sections of the Mandible Obtained by CT Scanning.

The external structure of the mandible is not only under the control of genetic factors, but is also influenced by biomechanical factors such as the masticatory muscles. As is well known, one of the characteristics of the morphology of the mandible which represents the influence of these factors is the gonial angle. It varies from a low angle with strong masseter development to a high angle with reduced muscle activity. The aims of this study were to investigate the internal structures of vertical sections of the mandibular body and to evaluate the relationship between these structures and the gonial angle.A principal component analysis grouped all cortical thicknesses except for the buccal cortical bone thickness together with large loadings on the ame factor. Buccal cortical bone thickness was more variable than the other variables and showed a different pattern of variation.The gonial angle was associated with buccal and lingual cortical bone thickness in the second molar section, and was also related to the height of the symphysis and the height and width of the second molar section. These results confirmed the relationship between the gonial angle and the size of the mandibular body at the second molar region.This study provided evidence that masticatory function influenced on both the internal structure and the size of mandibular body.