Influence of alveolar bone thickness and bucco-palatal inclination on root resorption of lateral incisors in unilateral maxillary impacted canines: a retrospective observational study.

BACKGROUND: This study aimed to investigate the potential associations between alveolar bone thickness, bucco-palatal inclination of maxillary lateral incisors, and lateral incisor root resorption in patients with unilateral maxillary impacted canines (UMICs). METHODS: A total of three hundred and five subjects (120 males, 185 females; mean age, 16.39 years; standard deviation, 4.04) with UMICs were included. Canine position and root resorption were assessed using CBCT. UMICs were divided into palatal, buccal and mid-alveolus groups (PICs, BICs and MAICs), with 117, 137 and 51 subjects, respectively. Alveolar bone thickness and bucco-palatal inclination of lateral incisors were measured using the Dolphin software. RESULTS: The prevalence of lateral incisor root resorption was significantly lower in the BICs (13.9%) than MAICs (29.4%) and PICs (29.1%). Alveolar bone thickness of the apical area was smaller in UMICs with lateral incisor root resorption than no resorption in both PICs (8.33 ± 1.64 vs 10.53 ± 2.55 mm) and BICs (8.94 ± 1.85 vs 10.76 ± 2.28 mm). Furthermore, lateral incisors on the impacted side were more buccally inclined in PICs with lateral incisor root resorption than no resorption, while in both BICs and MAICs, there was no statistical difference between lateral incisor root resorption than no resorption. Moreover, alveolar bone thickness of the apical area, rather than bucco-palatal inclination of lateral incisors, was significantly correlated with lateral incisor root resorption both in PICs and BICs. CONCLUSIONS: Lateral incisor root resorption is less common in BICs. Thinner alveolar bone thickness at the apical area of lateral incisors can be considered as a potential risk factor for lateral incisor root resorption in UMICs.

Impact of molar teeth distalization by clear aligners on maxillary alveolar bone thickness and root resorption: a three­dimensional study.

OBJECTIVE: This study aimed to evaluate the impact of molar teeth distalization movement by clear aligners on changes in the alveolar bone thickness and orthodontically induced inflammatory root resorption (OIIRR) in maxillary molars using conebeam computed tomography (CBCT). MATERIALS AND METHODS: Three-dimensional CBCT scans of 35 adult patients (one hundred forty maxillary molars) with pre-designed selection criteria and a mean age of 24.4 ± 7.1 years were included. The measured parameters, including alveolar bone thickness for maxillary molars and root resorption (OIIRR), were analyzed using pre-and post-treatment CBCT (T0 and T1, respectively) with Invivo 6.0 software. RESULT: Post-treatment, relevant statistically significant changes included deposition of bone in the average palatal surface of the 1st molars. The reduction of bone was seen in the average buccal surface of the first molars and both surfaces of the second molars. Regarding root length after treatment, the average maxillary 1st molar roots showed significant OIIRR (p < 0.001). CONCLUSION: Clear aligner treatment could effectively reduce the incidence of alveolar bone thickness reduction and OIIRR in treating Class II malocclusions compared to conventional braces, as shown in previous studies. This research will aid in fully grasping the benefits of clear aligners.

Dentofacial characteristics and age in association with incisor bony support in adult female patients with bimaxillary dentoalveolar protrusion.

OBJECTIVE: The aim of this study was to analyse the correlation between incisor alveolar bone thickness (IABT) and dentofacial characteristics or age in adult female patients with bimaxillary dentoalveolar protrusion (BDP). Evaluating the contribution of these characteristics may help to predict the IABT differences in this patient population. SETTING AND SAMPLE POPULATION: A retrospective study whose sample comprised 80 pretreatment adult female patients with BDP (mean age 24.6 years). MATERIALS AND METHODS: The IABT of the bimaxillary central incisors was measured by cone-beam computed tomography. Among the types of IABT, the apical trabecular bone thickness was measured with a quantitative method. The sagittal skeletal pattern, facial divergence, the incisor inclination angle, and mandibular plane angulation were determined by cephalometric analysis. A backward linear multiple regression was performed to analyse the associations between IABT and these characteristics. RESULTS: Three dentofacial traits and age were associated with IABT. Patients with increased age and facial divergence tended to have a thinner mandibular incisor bone support, while increased root length was associated with a thicker mandibular incisor apical bone thickness. Increased U1-SN and facial divergence may lead to a thinner maxillary incisor palatal bone, while increased U1-SN resulted in a thicker maxillary incisor labial bone. CONCLUSIONS: The bony support of the incisors is associated with age and dentofacial traits. Increasing age and facial divergence are considered risk factors for alveolar defects in female patients with BDP. In contrast, increased root length is associated with a thicker mandibular incisor apical bone support.

Relationship Between Crown to Root Ratio and Alveolar Bone Support in Patients With Unilateral Cleft Lip and Alveolus.

OBJECTIVES: To evaluate the tooth lengths, crown to root ratios (CRRs), and alveolar bone support (ABS) around cleft-adjacent maxillary central incisors (U1s) in patients with unilateral cleft lip and alveolus (UCLA) and to investigate the relationships between CRR and ABS. DESIGN: This is a retrospective study. SETTING: Cleft Lip and Palate Care Center of Shanghai Ninth People's Hospital, Shanghai, China. PATIENTS: Fifty-eight Chinese patients with UCLA. MAIN OUTCOME MEASURE: Cone beam computed tomography data from 58 nonsyndromic patients with UCLA (36 males, 22 females; mean age = 12.65 ± 3.64 years) were evaluated. Crown length and root length, alveolar bone thickness (ABT), and the distances between the cementoenamel junction and alveolar bone crest on 4 surfaces of cleft-adjacent U1 were measured and compared with those of noncleft side in the same patients. Crown to root ratio and frequency of dehiscence were calculated and comparisons were also made between cleft and noncleft sides. Regression analysis was performed to explore the association between CRR and ABS. RESULTS: The CRR of cleft-adjacent U1 and alveolar bone crest heights (ACHs) on the 4 surfaces were significantly greater than those of noncleft side (P < .01). A 3 mm labial, all lingual, and apico-distal ABTs decreased on the cleft side (P < .01). A positive correlation was found between lingual ACH and CRR (R = 0.316, P < .05), between the 3 mm (R = 0.417, P < .05) and 6 mm labial (R = 0.448, P < .05) ABT and CRR. A negative correlation was found between the 3 mm and 6 mm labial ABTs and the root length. CONCLUSIONS: It can be suggested that the CRR is related to ACH and ABT. The lingual ACH, the 3 mm, and 6 mm labial ABTs tend to increase with the increasing CRR.

Evaluation of facial and palatal alveolar bone thickness and sagittal root position of maxillary anterior teeth on cone beam computerized tomograms.

BACKGROUND: Amount of bone covering the facial and palatal surface of the root and the sagittal root position are important parameters while considering an immediate implant placement. AIMS: This study measures the distance from cement-enamel junction (CEJ) to alveolar crest and thickness of alveolar bone of maxillary anterior teeth facially and palatally at 5 different points. MATERIALS AND METHODS: CBCT scans of 79 systemically healthy patients were evaluated by two calibrated and independent examiners. Measurements like: 1) distance from CEJ to Crest. 2) Thickness of facial and palatal alveolar bone at five different points a) Crest, b) 2 mm from the crest, c) mid root level, d) apical 3rd, e) apex. 3) Sagittal root position. 4) Labiopalatal distance at the apex. 5) Length of the bone from apex to the nasal floor for incisors. 6) Presence of fenestrations and dehiscences were assessed. RESULTS: Healthy maxillary anteriors were evaluated and less than 2 mm bone was seen at all five points, 0.5 to 1 mm bone is seen in all anteriors at crest, 2 mm from crest, midroot, apical 3rd level. 1 to 2 mm is seen at apex. Labiopalatal width at apex ranged from 3 mm to 13 mm with a mean of 7.45 ± 2.24 mm for centrals, 7.69 ± 2.14 mm for lateral incisors, and 6.76 ± 2.42 mm for canines. CONCLUSION: The present study supports the finding of very thin facial bone over maxillary anteriors and frequent occurrence of fenestrations and dehiscences. Pre-treatment evaluation of alveolar bone surrounding the maxillary anteriors is important to avoid complications during implant placement.

A Cone-Beam Computed Tomographic Study of Alveolar Bone Morphology in Patients With Unilateral Cleft Lip and Palate.

OBJECTIVE: To evaluate the bony support around the teeth adjacent to the unilateral cleft lip and palate (ULCLP) using cone-beam computed tomography. METHODS AND MATERIALS: Cone-beam computed tomographies of 48 cleft-adjacent teeth (28 anterior and 20 posterior to the cleft) and 48 noncleft control teeth were evaluated. The alveolar bone thickness at 3 and 6 mm apical to the cement-enamel junction (CEJ), the distance between the alveolar crest and CEJ (Alv-CEJ), and the presence of fenestration were assessed in buccal, palatal, and proximal surfaces. RESULTS: The alveolar bone on the buccal and palatal sides of the teeth anterior to the cleft was significantly thinner than the noncleft teeth (all P < .05). The Alv-CEJ was significantly greater on the buccal and distal surfaces of the teeth anterior to the cleft (P < .001 and P = .010, respectively) and on the palatal and mesial surfaces of the teeth posterior to the cleft (P = .024 and P = .003, respectively) when compared to the noncleft teeth. The frequency of reduced alveolar bone height (>2 mm) was higher than noncleft side for buccal and distal sides of the teeth anterior to the cleft (P = .016 and .006, respectively) and the buccal and mesial sides of the teeth posterior to the cleft (P = .008 and <.001, respectively). The teeth anterior to the cleft had a higher prevalence of fenestration (P = .004). CONCLUSION: Reduced alveolar bone height is more common in the cleft side compared to the control side. The teeth anterior to the ULCLP have thinner alveolar bone support and higher frequency of fenestration.

Combining virtual model and cone beam computed tomography to assess periodontal changes after anterior tooth movement.

BACKGROUND: Orthodontic force may affect not only periodontal ligaments, but also the alveoloar bone and the gingiva according to the type of tooth movements. The authors assessed changes in gingival thickness (GT) and alveolar bone thickness (ABT) after orthodontic treatment using a new method. METHODS: This study included 408 teeth (208 central incisors, 200 lateral incisors) from the upper and lower 4 anterior teeth of 52 patients who had completed orthodontic treatment. GT and ABT were measured using virtual casts fabricated from impressions and cone beam computed tomography (CBCT). Two sectioned images of every tooth axis were acquired by partitioning each tooth with a line connecting the midpoint of the incisal edge to the midpoint of the cementoenamel junction in the virtual models and the root apex in CBCT images. After superimposing the two sectioned images, GT and ABT were measured before and after orthodontic tooth movement. Correlations between GT and ABT before and after treatment, and changes in GT and ABT associated with sex, tooth arch, tooth position, orthognathic surgery, and tooth inclination and rotation were assessed. RESULTS: Before orthodontic treatment, GT and ABT were significantly correlated. Patients who underwent orthognathic surgery exhibited an increase in GT thickness compared with those who did not. ABT was significantly decreased in proclined teeth and in rotated teeth. CONCLUSIONS: GT and ABT can be affected by the nature of tooth movement and can be accurately assessed by comparing sectioned CBCT images and virtual models.

Three-dimensional evaluation of alveolar bone thickness of mandibular anterior teeth in different dentofacial types.

AIM: The aim of this randomized study was to compare the alveolar bone thickness (ABT) of the mandibular incisor teeth of dental and skeletal Class I, II, and III adult patients at labial and lingual aspects of the bone and develop recommendations for the associated movements of teeth in this region, taking vertical facial type into consideration. MATERIAL AND METHODS: : Sixty-two Class I, 74 Class II, and 63 Class III patients - aged between 20 and 45 - were assigned to three subgroups - high (H), low (L), and normal (N) growth patterns. On the axial slices of computerized tomographies, the measurements for the ABT on labial and lingual sides of the mandibular incisors were carried out at three levels. RESULTS: In Class I group, at apex region, ABT of subgroups N and L were greater than H, at labial side. In Class II, ABT of subgroups N and L were greater than H, at apex at both sides and cervical lingual region. Similarly, ABT of subgroup L of Class III group was greater than H, at labial and lingual apex, mid-root regions. In Class II, the ABT of subgroup H was greater than L, at lingual cementoenamel junction. CONCLUSIONS: ABT of mandibular incisors of Class I patients is not affected from vertical pattern except for apical region. There is not a thick bone on the lingual side of the Class II, high-angle patients. The ABT of the Class III, high-angle patients is thin as a risk factor for proclination.

Evaluation of Bone Thickness and Density in the Lower Incisors' Region in Adults with Different Types of Skeletal Malocclusion using Cone-beam Computed Tomography.

OBJECTIVES: To evaluate the bone thickness and density in the lower incisors' region in orthodontically untreated adults, and to examine any possible relationship between thickness and density in different skeletal patterns using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: The CBCT records of 48 patients were obtained from the archive of orthodontic department comprising three groups of malocclusion (class I, II and III) with 16 patients in each group. Using OnDemand 3D software, sagittal sections were made for each lower incisor. Thicknesses and densities were measured at three levels of the root (cervical, middle and apical regions) from the labial and lingual sides. Accuracy and reliability tests were undertaken to assess the intraobserver reliability and to detect systematic error. Pearson correlation coefficients were calculated and one-way analysis of variance (ANOVA) was employed to detect significant differences among the three groups of skeletal malocclusion. RESULTS: Apical buccal thickness (ABT) in the four incisors was higher in class II and I patients than in class III patients (p < 0.05). There were significant differences between buccal and lingual surfaces at the apical and middle regions only in class II and III patients. Statistical differences were found between class I and II patients for the cervical buccal density (CBD) and between class II and III patients for apical buccal density (ABD). Relationship between bone thickness and density values ranged from strong at the cervical regions to weak at the apical regions. CONCLUSIONS: Sagittal skeletal patterns affect apical bone thickness and density at buccal surfaces of the four lower incisors' roots. Alveolar bone thickness and density increased from the cervical to the apical regions.

Three-dimensional assessment of alveolar bone changes and root resorption in extraction patients after fixed orthodontic treatment: A prospective study.

BACKGROUND: The aim of this study was to evaluate the alveolar crestal bone height, alveolar bone thickness, and root resorption in mandibular incisors after fixed orthodontic treatment. METHODS: A total of 35 patients (mean age 17.02 ± 3.24 years) with moderate to severe mandibular anterior crowding requiring first premolar extraction were included. Cone beam computed tomography scans of the mandibular anterior region were obtained from the patients before and after orthodontic treatment. The alveolar crestal bone height, cortical bone thickness (CBT) (at apex and midroot level), labial and lingual alveolar bone thickness, and root resorption were assessed for all mandibular incisors. Paired Student's t test was used to compare pretreatment and post-treatment alveolar bone changes and root resorption. RESULTS: A significant decrease in lingual crestal bone height was observed in all mandibular incisors after orthodontic treatment (P < 0.001). Lingual CBT decreased at the midroot level significantly for all mandibular incisors after completion of orthodontic treatment (P < 0.001). A significant decrease in total lingual bone thickness was observed in all mandibular incisors (P < 0.001). Root lengths of mandibular incisors decreased significantly in the sagittal and coronal sections after orthodontic treatment (P < 0.001). CONCLUSIONS: Fixed orthodontic treatment with premolar extraction results in a significant reduction of alveolar crestal bone height, CBT (at midroot level), and alveolar bone thickness on the lingual aspect of mandibular incisors. Significant orthodontically induced inflammatory root resorption was observed in all mandibular incisors after orthodontic treatment.

Analysis of mandibular molar anatomy in Taiwanese individuals using cone beam computed tomography.

Background/purpose: Before periapical surgery in the mandibular posterior teeth is performed, the thicknesses of the buccal alveolar bone wall and buccolingual root might be a critical issue. This study aimed to assess the anatomical structure of the posterior region of the mandible in Taiwanese individuals using cone-beam computed tomography (CBCT). Materials and methods: The CBCT images of 96 Taiwanese individuals (51 male and 45 female), which included 192 mandibular first molars and 192 mandibular second molars, were imported into medical imaging software to measure the buccal alveolar bone thickness and buccolingual root thickness at 3 mm above the root apex. Statistical analysis was conducted to examine the impact of tooth position, gender, and age on the anatomical position of mandibular molars. Results: The buccal alveolar bone thickness at 3 mm above the root apex of the mandibular second molar demonstrates a significantly higher value when compared to that of the first molar. Nonetheless, concerning the buccolingual root thickness, no significant differences were observed between these two teeth. In addition, the buccal alveolar bone thickness and buccolingual root thickness at 3 mm above the root apex may not be influenced by gender and age. Conclusion: The anatomical structures of the posterior region of the mandible in Taiwanese individuals exhibited variations between the mandibular first and second molars. However, these differences were not influenced by gender or age.

A quantitative three-dimensional comparative study of alveolar bone changes and apical root resorption between clear aligners and fixed orthodontic appliances.

BACKGROUND: This study aimed to evaluate and compare the alveolar bone changes and to investigate the prevalence and severity of orthodontically induced inflammatory root resorption (OIIRR) of maxillary incisors in patients who received treatment with clear aligners (CA) versus conventional fixed appliances (FA), using cone-beam computed tomography (CBCT). METHODS: One hundred sixty maxillary incisors from 40 patients with similar baseline characteristics based on the American Board of Orthodontics discrepancy index scores were divided into the CA and FA groups. The dentoalveolar quantitative changes were analyzed using pre- (T0) and post-treatment (T1) CBCT. The measured parameters included alveolar bone thickness (ABT), alveolar bone height (ABH), root length (OIIRR), and maxillary incisor inclinations. RESULTS: Post-treatment, the average palatal and total ABT significantly decreased in central and lateral incisors in the FA group. In contrast, the CA group's average labial ABT of the lateral incisors decreased considerably. Regarding the ABH, both groups showed significant labial and palatal marginal bone resorption. In both groups, root lengths significantly decreased after treatment (p < 0.005). The inter-group comparison revealed that ABT and root length had significantly decreased in the FA group compared to the CA group, while the ABH showed no significant difference between the two groups. The mean absolute reductions of ABT and OIIRR in the CA group were significantly less (- 0.01 ± 0.89 and 0.31 ± 0.42) than those in the FA group (0.20 ± 0.82 and 0.68 ± 0.97), respectively. CONCLUSIONS: CA and FA treatments appear to cause a significant ABT reduction and a statistically significant increased OIIRR in the maxillary incisor region, with a greater extent expected with FA treatment. However, the increased OIIRR values in the majority of both groups' cases were not clinically significant. Both treatment modalities resulted in a significant ABH reduction, with the highest found in the labial side of lateral incisors in the CA group.

A CBCT Study of Labial Alveolar Bone Thickness in the Maxillary Anterior Region in a Teaching Hospital Population in the Eastern Province of Saudi Arabia.

BACKGROUND AND OBJECTIVES: Labial alveolar bone thickness in the maxillary anterior region is the key factor in the placement of implants. Differences in the thickness of the bone are reported among different ethnic groups. Thus, the present study was aimed at assessing labial alveolar bone thickness in the maxillary anterior region in the population of the eastern province of Saudi Arabia. MATERIALS AND METHODS: The six anterior teeth in each of the 186 CBCT sagittal images were analyzed at three points: Point A from the facial plate at the level of the bone crest to the coronal root third, Point B to the mid-root surface, and Point C to the apical third. Crest height (Point D) was measured as the distance from the CEJ to the alveolar bone crest. The analysis was done using SPSS version 20. A p-value of <0.05 was considered statistically significant. RESULTS: The bone thickness at any given point (Point A, Point B, or Point C) was less than the preferred bone thickness of 2 mm in all six teeth. The thickness was minimum at Point B, maximum at Point C, and intermediate at Point A. This difference was found to be statistically significant (p-value < 0.05). The crestal height (Point D) was less than 3 mm, and it was not statistically significant. Comparison of bone thickness on the right and left sides for any given point was not statistically significant except at Point A in the central incisor, where it was statistically significant (p-value = 0.035). Gender comparison of bone thickness showed no difference at Point A; however, at Points B and C, it showed statistical significance (p-value < 0.05). CONCLUSIONS: The alveolar bone thickness being <2 mm in the labial anterior region warns of the importance of the proper assessment of bone during implant placement to have a predictable outcome.

A comparison of maxillary canine retraction into healed and recent extraction sites using cone beam computed tomography: a randomized clinical trial.

OBJECTIVES: To compare maxillary canine retraction between healed and recent extraction sites by assessing movement rate, canine dentoalveolar changes, molar rotation, and anchorage loss using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Twenty-eight patients (16-26 years old) who had bimaxillary protrusion and orthodontic treatment planned with extraction of first premolars were randomly distributed into two groups and treated using a straight wire appliance. In the recent group (RG), the upper first premolars were extracted 2 weeks before the initiation of canine retraction (after tooth alignment). In the healed group (HG), the upper first premolars were extracted before tooth alignment. Movement rate, canine dentoalveolar changes, molar rotation, and anchorage loss were assessed using CBCT. RESULTS: Movement rate, canine alveolar bone dimensions, canine rotation, and rotation and mesial movement of the first molar were not significantly different between groups (P > .05). Canine tipping was greater in RG (P = .001). CONCLUSIONS: Retracting canines into recent extraction sites compared with healed sites showed greater distal tipping of the canine with no differences in movement rate, canine alveolar bone dimensions, canine rotation, molar rotation, and anchorage loss.

Three-dimensional Analysis of Alveolar Bone With and Without Periodontitis.

OBJECTIVE: The aim of this study was to investigate the alveolar bone density and thickness in Chinese participants with and without periodontitis. METHODOLOGY: This study was retrospective and cross-sectional in nature and used cone-beam computed tomography (CBCT) to evaluate alveolar bone loss, bone density, and bone thickness around 668 mandibular molars (344 periodontally healthy teeth and 324 teeth with periodontitis). Comparative statistical tests were done related to the age, sex, tooth type, tooth side, and degree of bone loss. The significance level was set to be P < .05. RESULTS: The alveolar bone density significantly differed between the healthy and periodontitis groups (mean difference = 24.4 Hounsfield units; P = .007). Similarly, the alveolar bone thickness of the healthy group was significantly higher than that of the periodontitis group (4.6 ± 1.8 mm compared to 4.2 ± 1.1 mm). Teeth in females demonstrated a significantly (P ˂ .001) higher bone density compared with males in both healthy and compromised groups. However, males showed a significantly (P ˂ .05) thicker bone of the teeth than females in relation to the healthy group. The alveolar bone density and thickness in both healthy and periodontitis groups significantly differed between the first and the second molars (P < .001). The alveolar bone thickness had a highly significant difference (P < .001) between the different degrees of bone loss. CONCLUSIONS: Alveolar bone thickness and density were reduced at periodontally diseased teeth.

Incisor position and alveolar bone thickness.

OBJECTIVES: To evaluate incisor position and its relationship to alveolar bone in untreated optimal occlusions and in untreated Class II malocclusions. MATERIALS AND METHODS: Fifty-seven lateral cephalograms of individuals with naturally occurring optimal occlusions (mean age = 23 years) were used to assess positions of central incisors and their relationships to alveolar bone. Data were compared to a sample of 57 individuals with untreated Class II malocclusions with concurrent anterior-posterior (AP) skeletal discrepancies (mean age = 16.9 years). RESULTS: Significant intergroup differences were found for AP jaw relationship, maxillary alveolar bone thickness, mandibular incisor inclination, maxillary incisor root distance to labial surface of alveolar bone, and mandibular incisor root apex distance to labial surface of alveolar bone. Small differences between females and males existed for several variables. In both samples, maxillary incisor roots were located closer to the labial surface of alveolar process than to the palatal surface by roughly a 2:1 ratio. Mandibular incisor root apices were generally equidistant from the labial and lingual surfaces of the alveolus in the optimal sample but closer to the lingual surface in the Class II sample. CONCLUSIONS: Maxillary incisors tend to occupy the anterior one-third of the alveolus in untreated individuals, regardless of AP interarch dental relationships or AP jaw relationships. Mandibular incisor root apices tend to be centered within the alveolus in untreated optimal occlusions but are more positively inclined, and their root apices are more posterior in untreated Class II malocclusions.

Relationship between maxillary central incisors and incisive canal: a cone-beam computed tomography study.

BACKGROUND: This study aimed to assess the relationship between the maxillary incisors and the incisive canal (IC) using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Archived CBCT scan from 120 subjects (60 males and 60 females, mean age 34.2 ± 13.1 years) were analysed in this cross-sectional study. The following variables were measured: incisor/palatal plane (PP), IC/PP angles, palatal alveolar bone width (PABW) at apex, IC width, inter-root width at apex and IC level to incisor apex. The relationship between the incisors and IC with respect to sex and age was calculated using one-way analysis of variance, independent samples t-test, and regression analysis. RESULTS: The confidence level was set at 95%. Results showed that half of the study population exhibited IC palatal opening at the level of the maxillary incisor apices. Significant associations were observed between IC/PP and incisor/PP angles and between IC width and PABW at the apical level (p < 0.05), and between age and IC width in the sagittal and axial perspectives and age and IC level relative to the incisor apices. A significant association was observed between sex and IC/PP angle, IC width in the sagittal perspective, and PABW at the apical level. The association was found between IC and maxillary incisors angulations but not between IC width and inter-root distance. CONCLUSIONS: Age showed varied associations while sex was significantly associated with most variables assessed.

The Effectiveness of Periodontally Accelerated Osteogenic Orthodontics (PAOO) in Accelerating Tooth Movement and Supporting Alveolar Bone Thickness During Orthodontic Treatment: A Systematic Review.

The current review aimed to critically and systematically evaluate the available evidence regarding the effectiveness of periodontally accelerated osteogenic orthodontics (PAOO) in accelerating orthodontic tooth movement and supporting the alveolar bone. Additionally, this review aimed to analyze the untoward effects of this procedure and the patient-reported outcome measures. A comprehensive electronic search was performed on 10 databases in addition to a manual search to retrieve all relevant studies. Randomized controlled trials (RCTs) were only included in this review. The interventional group was the PAOO procedure, whereas the control group was either a non-accelerated traditional fixed orthodontic treatment or an accelerated treatment using any other intervention. The Cochrane risk of bias tool for randomized controlled trials (RoB 2) was employed to estimate the risk of bias in the included studies. The current review included eight RCTs evaluating 175 participants (63 males and 112 females) with a mean age ranging from 18.8 to 29.6 years. Five of them assessed the effectiveness of PAOO versus traditional orthodontic treatment, i.e. without any adjuvant surgical intervention. At the same time, the remaining three studies evaluated the effectiveness of PAOO versus corticotomy-only as an adjunctive procedure. The PAOO accelerated the leveling and alignment stage from 39% to 47% and accelerated the retraction of the upper anterior teeth from 41% to 61% compared to conventional orthodontic treatment. One study only indicated that PAOO reduced treatment time by 30.3% versus a corticotomy-only as an adjunctive procedure. No significant side effects have been reported with the PAOO procedure. The PAOO procedure was effective in accelerating orthodontic movement and tended to increase the thickness of the alveolar bone. But most periodontal outcome measures regarding PAOO application were not comprehensively covered in the included trials.

Data on alveolar mandibular bone thickness in Class I skeletal patient with bimaxillary protrusion.

The alveolar bone thickness influences both diagnosis and limitation of tooth movement, therefore significance retraction was commonly applied in treating patients with bimaxillary protrusion. This is a retrospective data collection of pre and post treatment lateral cephalographs from 18 to 40 years old patient treated with four premolars extraction. The alveolar mandibular bone thickness was identified in sagittal planes with Image-J software based on cephalometry lateral radiographs. Statistical analysis namely Wilcoxon test and Pearson correlation analysis coefficient were used to understand the correlation of alveolar mandibular bone thickness variables and mandibular incisors position to skeletal profile treated with first premolars extraction are presented. This data is essential for advancing in a further understanding of Class I skeletal patients with bimaxillary protrusion.

Relationship between buccal alveolar bone thickness and crown-to-root dimensions around mandibular first and second molars: A cone-beam-computed tomography-based study.

BACKGROUND: Assessment of buccal alveolar bone thickness (ABT) and crown-to-root dimensions are essential in implant density; therefore, three-dimensional evaluation of these parameters provides a superior visualization than conventional radiographs. OBJECTIVE: The present cross-sectional cohort study aims to investigate the relationship between buccal ABT and crown-to-root dimensions around the mandibular first and second molars using cone-beam-computed tomography (CBCT). METHODS: Initially, CBCT-based scans from 271 individuals were assessed. Based on the inclusion and exclusion criteria, 171 CBCT-based scans were excluded. In total, 100 CBCT-scans were included in the present investigation and processed for data extraction. On the mandibular first and second molars, the mesial and distal root lengths and mesiodistal diameter of the crowns were measured. The pulpal floor served as a reference point for assessment of root length. The buccal ABT was measured at the coronal, middle and apical one-third of the root. Statistical analysis was performed and the level of significance was set at P< 0.01. One-hundred CBCT-scans from 294 mandibular teeth (137 first molars and 157 second molars) were included. One hundred and eighty-nine and 105 teeth were from males and females, respectively. RESULTS: The normality plot showed a normal data distribution. The mesiodistal crown width showed a weak yet significant correlation with mesial root length (r= 0.137), bone thickness at mesial apical third (r= 0.180), distal apical (r= 0.157) and distal coronal third (r= 0.161). Bone thickness at mesial, middle and apical third correlated significantly with one other (r= 0.786). CONCLUSION: There is a direct correlation between the buccal ABT and tooth dimensions around the mandibular first and second molars.