Correlation between Dental Vestibular-Palatal Inclination and Alveolar Bone Remodeling after Orthodontic Treatment: A CBCT Analysis

CBCT Evaluation of Alveolar Bone Change and Root Resorption after Orthodontic Treatment: A Retrospective Study

BACKGROUND

For years, there has been a long debate about the impact of orthodontic treatment on the periodontium of patients. Therefore, it is important to understand the effects of orthodontic forces on the periodontium. The objective of this study was to evaluate the height of the alveolar bone at the four surfaces of specific teeth and the root length of the central incisors before and after orthodontic treatment.

MATERIALS AND METHODS

CBCTs from a group of fifty patients were evaluated before (T0) and after orthodontic treatment (T1). Evaluations of the alveolar bone were performed by measuring the distance from the most apical point of the marginal portion to the CEJ at the buccal (B-ABL), lingual (L-ABL), mesial (M-ABL), and distal (D-ABL) surfaces of the central incisor (CI), first premolar (1st PM), and first molar (1st M). Meanwhile, root resorptions were evaluated by measuring the distance from the center of the tooth at the CEJ to the most apical point of the central incisor.

RESULTS

The reduction in the alveolar bone level was highest at the buccal segment (75%) and lowest at the distal (42%) segment, although the decrease was not statistically significant. Root resorption, in terms of reduction in the total length, was detected in the upper central incisor.

CONCLUSIONS

Fixed orthodontic treatment can produce a significant reduction in root length, but not at the level of the alveolar bone.

Management of Patients Receiving Anticoagulation Therapy in Dental Practice: A Systematic Review

BACKGROUND

Anticoagulant drugs are a valuable tool for minimizing thrombotic risks in at-risk patients. The purpose of this study is to conduct a literature review highlighting the management of these drugs during daily clinical dental practice.

MATERIALS AND METHODS

We limited our search to English-language papers published between 1 January 1989, and 7 March 2024, in PubMed, Scopus and Web of Science that were relevant to our topic. In the search approach, the Boolean keywords "anticoagulant AND dentistry" were used.

RESULTS

Twenty-five clinical trials were included for final review from 623 articles obtained from the databases Web of Science (83), PubMed (382), and Scopus (158), eliminating duplicates and 79 off-topic items, resulting in 419 articles after removing 315 entries and confirming eligibility. Overall, these studies support the use of local hemostatic measures to manage the risk of bleeding in patients on anticoagulant therapy undergoing dental procedures and highlight the importance of greater education and collaboration among healthcare professionals.

CONCLUSIONS

Research and clinical investigation have improved understanding and management of dental procedures in patients undergoing anticoagulant or antiplatelet therapy. Hemostatic agents, clinical protocols, risk factors, and continuous education are essential for navigating the complexities of anticoagulant therapy, ensuring optimal outcomes and enhancing patient well-being.

Changes in the alveolar bone morphology among different patterns of incisor inclination during the alignment phase in orthodontic treatment without premolar extraction

OBJECTIVE

The present study investigated bone remodelling in the upper and lower incisor regions depending on the inclination pattern during the alignment phase of orthodontic treatment (OT).

MATERIALS AND METHODS

This prospective clinical study included 71 patients undergoing OT without premolar extraction. Cone beam computed tomography scans were taken before and after the alignment phase and the changes in the inclination, alveolar bone height (ABH) and bone thickness (BT) at levels 2, 3, 4, 6, 8 and 9 mm starting from the cementoenamel junction (CEJ) were determined.

RESULTS

Teeth were divided into 'Retroinclination' (lingual crown inclination <0°), 'Proclination-low' (buccal crown inclination between 0° and 5°), or 'Proclination-high' (buccal crown inclination >5°). The alignment phase of OT resulted in ABH loss. The highest ABH loss in the maxilla was observed on the buccal side in the 'Proclination-high' and was 0.71 mm. ABH loss by 1.1 mm was observed in the mandible on the lingual side in the 'Retroinclination' group. The most significant changes in BT by up to 2 mm were observed at levels 6, 8 and 9 mm and these changes exhibited a moderate to strong correlation with the alterations in the inclination of individual incisors. At levels 2, 3 and 4 mm, the highest decrease in BT by up to 0.83 mm was observed on the palatal side of upper incisors in the 'Proclination-high' group.

CONCLUSION

The direction and amount of tooth inclination partially determine changes in the bone parameters during the alignment phase.

Impact of molar teeth distalization by clear aligners on maxillary alveolar bone thickness and root resorption: a three‑dimensional 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.

Evaluation of Enamel Surfaces after Different Techniques of Interproximal Enamel Reduction

According to the literature, interproximal enamel reduction (IER) has become a consolidated technique used in orthodontic treatments to gain space in particular situations such as dental crowding, non-extractive therapies, tooth-size discrepancies, and prevention of dental relapse. There are different methods to realize stripping, and enamel surfaces resulting after this procedure can be analyzed with SEM. The aim of this study was to analyze how different devices of IER leave the surface of the teeth. One hundred and sixty freshly extracted, intact human lower incisors were included in the study, fixed in a plaster support, and then processed with four different techniques of enamel reduction and finishing. Then, they were divided randomly into eight groups (A1-A2, B1-B2, C1-C2, D, and E), each containing twenty teeth. The A, B, and C groups were divided into two subgroups and then all the teeth were observed at SEM. Each digital image acquired by SEM showed that there were streaks on the surfaces, due to the cutter used. The results of this study showed that only group C2 (tungsten carbide bur followed by twelve steps of medium-fine-ultrafine 3M Soft Lex disks) has a few line, which is very similar to group E (untreated group), while the other groups have a lot of lines and show a rougher final surface.

Bone Remodeling during Orthodontic Movement of Lower Incisors-Narrative Review

The tooth movement in the alveolus is possible due to bone remodeling. This process could be the risk factor for the formation of gingival recessions-the most common side effects of orthodontic therapy. Gingival recessions are found 5.8-11.5% more frequently among the orthodontically treated patients. What is more, anterior mandibular teeth are the ones most prone to gingival recession dehiscences and fenestrations. The aim of this narrative review was to evaluate, based on CBCT (Cone beam computed tomography) scans, the changes in the alveolar bone of lower incisors in adolescent and adult patients after orthodontic tooth movements. From the pool of 108 publications, a total of 15 fulfilled the criteria of this review. Both retrospective and prospective longitudinal studies-using CBCT or CT (Computed Topography) and evaluating alveolar bone changes in mandibular incisors during orthodontic treatment performed before and after teeth movement-were included. In the group of growing patients, either proclination or retroclination of mandibular incisors led to increase of the distance from CEJ (cementoenamel junction) to marginal bone crest. The difference in bone loss was greater on the lingual side of the incisors in both types of tooth movement. The results were similar for adults patients. The thickness of the alveolar bone was reduced after proclination (total bone thickness) among growing and non-growing patients and retraction (lingual and buccal) of lower anterior teeth in the group of growing patients. The only improvement was measured for buccal thickness of mandibular incisor in bimaxillary protrusion patients treated with extraction therapy. The control of retraction movement (more root than crown movement) enhanced preservation on bone height and thickness. In order to minimize possible deterioration and place teeth in the center of alveolus, CBCT monitoring and scrupulous clinical evaluation are recommended.

The Role of Morphometric Characteristics of Anterior Maxilla in Planning the Interventions Accompanied by Orthodontic Teeth Movement – An Overview

The anterior maxilla or premaxilla is part of the upper jaw and the most significant content of this region, from the aspect of orthodontic therapy, are the incisor teeth. The frequency of complications during orthodontic movement of the upper incisors refers to a more detailed evaluation of the anatomical structures of the premaxilla. The aim of this study was to investigate morphological and morphometric characteristics of the anterior maxilla by cone beam computed tomography, which could be of interest for planning orthodontic teeth movement. By reviewing the available literature, we compared the values of the alveolar bone height, the distance between the alveolar crest and enamel – cement boundary, total alveolar bone width, the thickness of the buccal, and palatal plate, nasopalatine canal, and accessory canals of the anterior maxilla. The results of our study show changes in the labial and palatal aspects of the alveolar bone height during orthodontic interventions. Different results of the alveolar bone width are in correlation with gender, age, and type of orthodontic tooth movement. Distance between the nasopalatine canal and maxillary central incisors was estimated at the value from 4 to 6 mm, which is below the recommended value for maximum incisal retraction by Proffit. Research results show variations in shape, length, and diameter of the nasopalatine canal, which indicates individual varieties detected on cone beam computed tomography. Other anatomical structures and measures show an insignificant correlation with orthodontic teeth movement. According to the contradictory results of the available articles, it is required to achieve an individual approach to orthodontic interventions in the area of the anterior maxilla.

Modern 3D cephalometry in pediatric orthodontics-downsizing the FOV and development of a new 3D cephalometric analysis within a minimized large FOV for dose reduction

OBJECTIVES

Dose reduction achieved by downsizing the field of view (FOV) in CBCT scans has brought no benefit for pediatric orthodontics, until now. Standard 2D or 3D full-size cephalometric analyses require large FOVs and high effective doses. The aim of this study was to compare a new 3D reduced-FOV analysis using the Frankfurt horizontal (FH) plane as reference plane with a conventional full-size analysis using the Sella-Nasion (S-N) plane as reference plane.

MATERIALS AND METHODS

Thirty-eight CBCT data sets were evaluated using full- and reduced-FOV analysis. The measurements of a total of 20 skeletal and dental standard 3D full-size variables were compared with the measurements of 22 corresponding 3D reduced-FOV variables. Statistical analysis was performed to prove mathematic relation between standard and alternative variables. Regression analyses were carried out.

RESULTS

Coefficients of determination (R²) between 0.15 and 0.95 (p < 0.001-0.055) were described. All variables showed obvious relations of different strength except for SNA and its alternative Po_R-Or_R-A (°) (R² = 0.15, p = 0.055), but a second variable Ba_A (mm) showed stronger relation (R² = 0.28, p = 0.003).

CONCLUSIONS

All standard variables related to the reference plane S-N could be described with alternative variables related to the FH. Further research should define more reliable landmarks for coordinate systems and reference points.

CLINICAL RELEVANCE

Minimized large FOVs meet the demand of 3D cephalometric analyses and enable the application of CBCT scans in pediatric orthodontic patients in many specific indications. Dose reduction is accompanied by increasing access to all the advantages of 3D imaging over 2D imaging.

Effects of maxillary incisor inclination on dentoalveolar changes in class II division 1 and 2 non-extraction treatment for Caucasian children - A retrospective study using CBCT

OBJECTIVE

The objective of this study was to investigate the effects of maxillary central incisor (U1) inclination changes on alveolar bone and root length in the 20 Class II division 1 and 20 Class II division 2 (CII div1, CII div2) Caucasian adolescents treated without extraction.

MATERIAL AND METHODS

Forty U1s from each group were assessed for root length and alveolar variables at the crestal, mid-root, and apical levels using sagittal sections obtained from CBCT images pre- and post-treatment. Mixed MANOVAs, Repeated measures MANOVAs, Pearson correlations, and regression analyses were performed.

RESULTS

The facial bone height did not change significantly after an average of 15 degrees of proclination in the CII div2 group, whereas a statistically significant decrease in the palatal bone height was noted. However, in the CII div1 group, a statistically significant reduction in the facial and palatal bone height was observed with mild crown retroclination. Both groups had a significant decrease in total bone thickness at all levels, more decrease in the CII div2 group after treatment. No statistically significant difference in root length was observed between the groups during treatment.

CONCLUSIONS

The findings support that the flaring of retroclined U1s as a process for normalizing U1 inclination did not harm the facial alveolar bone height in the CII div2 non-extraction treatment. Crown proclination itself was not correlated to the amount of root resorption in Class II div1&2 non-extraction treatments in adolescents.

A study on the morphologic change of palatal alveolar bone shape after intrusion and retraction of maxillary incisors

The purpose of this study is to evaluate the changes in the palatal alveolar bone thickness and find the factors related to the resorption of the palatal alveolar bone caused by tooth movement after the maxillary incisors were retracted and intruded during orthodontic treatment. The study group comprised of 33 skeletal Class II malocclusion patients who underwent extraction for orthodontic treatment. Palatal alveolar bone thickness changes and resorption factors were identified and analyzed. The changes of maxillary central incisors and palatal alveolar bone thickness were measured, and the corresponding sample t test was performed using SPSS (IBM SPSS version 22). The amount of palatal alveolar bone resorption was measured and various parameters were analyzed to determine which factors affected it. Correlation analysis adopting the amount of palatal alveolar bone resorption as a dependent variable demonstrated that the SNB, mandibular plane angle, and the inclination of the maxillary central incisor were significantly correlated with before treatment. On the other hand, mandibular plane angle, angle of convexity, the inclination of the upper incisor, and the occlusal plane (UOP, POP) were significantly correlated with post-treatment. In addition, the variables related to palatal contour (PP to PAS, SN to PAS, palatal surface angle) and occlusal planes (UOP/POP) were significantly correlated with the difference in palatal bone resorption. During initial diagnosis, high angle class II with normal upper incisor inclination can be signs of high-risk factors. In addition, maintaining the occlusal plane during treatment helps to prevent palatal bone loss.

Alveolar bone changes in maxillary and mandibular anterior teeth during orthodontic treatment: A systematic review and meta-analysis

The association between tooth movement and remodelling of surrounding bone is controversial. To analyse the effect of tooth movement on alveolar bone changes in maxillary and mandibular anterior teeth by cone-beam computed tomography (CBCT). The Embase, Cochrane Library and Medline databases were searched without any language restrictions. Longitudinal studies using CBCT to observe alveolar bone changes of maxillary and mandibular anterior teeth during orthodontic treatment were included. Two independent reviewers performed the study selection, data extraction and methodological quality assessment. A total of 26 studies were included in this review, 14 of which were eligible for quantitative synthesis. In extraction cases, meta-analysis showed vertical bone loss on the labial (0.36 mm) and lingual (0.94 mm) sides of maxillary incisors, and lingual bone thickness decreased significantly at the cervical level (0.57 mm). In non-extraction cases, vertical alveolar bone loss was significant on the labial side (0.97 mm) and lingual side (0.86 mm) of mandibular incisors. Subgroup analysis for skeletal class III patients indicated that vertical alveolar bone loss was 1.16 mm on the labial side and 0.83 mm on the lingual side of mandibular incisors. The absence of high-quality studies and the high heterogeneity of the included studies were limitations of this systematic review and meta-analysis. Based on limited evidence, alveolar bone height and thickness, especially at the cervical level, decreased during both labial and lingual movement of anterior teeth.