Bone Height Changes Research Articles

Longitudinal Study of Bone Height Change between Two Approaches for Sinus Floor Elevation.

Background and Objectives: The purpose of this study is to assess the long-term maintenance of each approach of sinus elevation, the crestal approach and lateral approach, by comparing the radiographic results of each technique. Materials and Methods: In total, 103 patients who had undergone an implant procedure with either the crestal approach or lateral approach method applied to their maxillary molar edentulous area were included. Using orthopantomographs, the radiographic changes were consistently evaluated over 3 years after the procedure (immediately after procedure and 1 year, 2 years and 3 years after implant placement) Results: The radiographic evaluation after 3 years of implantation with sinus elevation showed a significant amount of bone formation (8.07 mm for crestal approach and 12.00 mm for lateral approach method). The largest amount of grafted height loss occurred during the 1 year, but the resorption was minimal (0.98 mm for crestal approach and 0.95 mm for lateral approach method) over the entire 3 years. Conclusions: Although the lateral approach showed more bone growth, the amount of bone resorption was similar to that of the crestal approach. Both methods showed the highest amount of bone resorption in the first year, and the amount of change thereafter was insignificant. It is judged that both methods can be used according to the situation to help implant placement.

Morphological changes in alveolar bone thickness and height after orthodontic proclination or labial movement combined with autogenous soft tissue grafting: a CBCT evaluation

BackgroundAutogenous soft tissue grafting is indicated in thin gingival biotypes before orthodontic proclination or labial movements to increase the keratinized gingiva and prevent gingival recession. However, its effect on local alveolar bone remodeling is unclear. The aim of this study was to investigate the effects of autogenous soft tissue grafting on local alveolar bone after orthodontic proclination or labial movements.MethodsSixteen patients with a thin scalloped gingival biotype, narrow keratinized gingiva, or thin cortical bone requiring orthodontic proclination or labial movement of teeth were included. Cone-beam computed tomography (CBCT) images were obtained before grafting and at least 6 months after surgery. Sixty mandibular teeth were included, and the vertical bone level and horizontal labial bone thickness were measured. The results were compared using paired t-tests or Wilcoxon signed-rank test.ResultsThe horizontal labial bone thickness increased, especially at 6 mm below the cementoenamel junction (CEJ) in the mandibular central and lateral incisors (P < 0.05). The total alveolar bone area of the canines, first premolars, and second premolars increased at 3, 6, and 9 mm below the CEJ, respectively, and the differences were statistically significant (P < 0.05). Additionally, vertical bone height increased minimally on the labial side, but the differences were not statistically significant (P > 0.05).ConclusionsNew bone regeneration was observed on the labial (pressure) side after autogenous soft tissue grafting, which may represent a mechanism to effectively prevent gingival recession and maintain periodontal health.IRB approvalAll the experimental procedures involving humans in this study were approved by the Medical Ethics Committee of Xiangya Stomatological Hospital, Central South University ( No. 20190048).

Evaluation of Different Fabrication Techniques for Reinforcement of Mandibular Implant-Retained Overdentures

Purpose: This study was performed to evaluate the effect of PEEK reinforced mandibular implant overdenture, in comparison with metal reinforced mandibular implant overdenture on bone height. Subjects and methods: Fourteen completely edentulous patients were selected with ages ranging from 50-70 years. All the patients received two implants in the inter-foraminal area of the mandible and maxillary complete dentures, then they were divided into two groups: group (I) seven patients received PEEK reinforced mandibular implant overdentures, group (II) seven patients received metal reinforced mandibular implant overdentures. The overdentures were functionally loaded after three months of implant insertion and retained with the implants using ball and socket attachments. Evaluation of crestal bone height changes around the implants and in the distal aspect of the ridge was done by CBCT at the time of denture insertion, 6 and 12 months. Results: The results revealed that there was a statistically significant decrease in amount of crestal bone loss in PEEK group than in metal group after 6 and 12 months. The results also showed that, there was non significant difference when comparing the changes in the distal bone height after 6 months then, there was a statistically significant decrease in amount of distal bone loss in PEEK group than in metal group after 12 months. Conclusion: PEEK reinforced implant overdentures have better results than those reinforced with metal, as they recorded favorable radiographic outcomes after one year of overdenture insertion regarding crestal and distal bone height changes.

Evaluation of Different Fabrication Techniques for Reinforcement of Mandibular Implant-Retained Overdentures

Purpose: This study was performed to evaluate the effect of PEEK reinforced mandibular implant overdenture, in comparison with metal reinforced mandibular implant overdenture on bone height. Subjects and methods: Fourteen completely edentulous patients were selected with ages ranging from 50-70 years. All the patients received two implants in the inter-foraminal area of the mandible and maxillary complete dentures, then they were divided into two groups: group (I) seven patients received PEEK reinforced mandibular implant overdentures, group (II) seven patients received metal reinforced mandibular implant overdentures. The overdentures were functionally loaded after three months of implant insertion and retained with the implants using ball and socket attachments. Evaluation of crestal bone height changes around the implants and in the distal aspect of the ridge was done by CBCT at the time of denture insertion, 6 and 12 months. Results: The results revealed that there was a statistically significant decrease in amount of crestal bone loss in PEEK group than in metal group after 6 and 12 months. The results also showed that, there was non significant difference when comparing the changes in the distal bone height after 6 months then, there was a statistically significant decrease in amount of distal bone loss in PEEK group than in metal group after 12 months. Conclusion: PEEK reinforced implant overdentures have better results than those reinforced with metal, as they recorded favorable radiographic outcomes after one year of overdenture insertion regarding crestal and distal bone height changes.

The Effect of Zirconia and Titanium as Abutment Materials on Peri-Implant Soft and Hard Tissues in Mandibular Implant Supported Over-denture

Purpose: To evaluate the effect of zirconia and titanium as abutment materials onperi-implant bone height changes and pocket depth in mandibular implant supportedover-denture. Subjects and methods: Ten completely edentulous patients wereselected from the Outpatient Clinic of the Faculty of Dental Medicine for Girls,Al-Azhar University. Two implants were implanted in the inter-foraminal area ofmandibular ridge. Two different abutments were screwed over implants. Right abutmentwas constructed of zirconia and left one was constructed of titanium. Construction ofmaxillary complete denture and mandibular implant supported over-denture for allpatients was performed. Radiographic and clinical evaluation of implants has beenperformed at denture insertion, 6 months, 9 months and 12 months. Results: Theprevious study illustrated that titanium abutments had significantly higher values ofbone height changes and pocket depth measurements than zirconia abutments duringfollow up period. Conclusion: Zirconia abutments had great superiority over titaniumabutments in preservation of peri-implant hard and soft tissues in mandibularimplant-supported over-denture within the follow up period of this study.

The Effect of Zirconia and Titanium as Abutment Materials on Peri-Implant Soft and Hard Tissues in Mandibular Implant Supported Over-denture

Purpose: To evaluate the effect of zirconia and titanium as abutment materials onperi-implant bone height changes and pocket depth in mandibular implant supportedover-denture. Subjects and methods: Ten completely edentulous patients wereselected from the Outpatient Clinic of the Faculty of Dental Medicine for Girls,Al-Azhar University. Two implants were implanted in the inter-foraminal area ofmandibular ridge. Two different abutments were screwed over implants. Right abutmentwas constructed of zirconia and left one was constructed of titanium. Construction ofmaxillary complete denture and mandibular implant supported over-denture for allpatients was performed. Radiographic and clinical evaluation of implants has beenperformed at denture insertion, 6 months, 9 months and 12 months. Results: Theprevious study illustrated that titanium abutments had significantly higher values ofbone height changes and pocket depth measurements than zirconia abutments duringfollow up period. Conclusion: Zirconia abutments had great superiority over titaniumabutments in preservation of peri-implant hard and soft tissues in mandibularimplant-supported over-denture within the follow up period of this study.

Alveolar bone height changes in the anterior tooth region before and after orthodontic treatment for Angle's Class II division 1 malocclusion and related factors.

The aim of this study was to observe the alveolar bone height changes in the anterior tooth region after orthodontic treatment for Angle's Class II division 1 malocclusion. Ninety-three patients treated from January 2015 to December 2019 were retrospectively analyzed, of whom 48 received tooth extraction and 45 did not. After orthodontic treatment, the alveolar bone heights in the anterior tooth regions of tooth extraction and non-extraction groups decreased by 67.31% and 66.94%, respectively. Except for the maxillary and mandibular canines in the tooth extraction group as well as the labial side of maxillary anterior teeth and the palatal side of maxillary central incisors of the non-extraction group, the alveolar bone heights of other sites significantly reduced (P<0.05). The reduction in the alveolar bone height of the tooth extraction group significantly exceeded that of the non-extraction group on the palatal side of maxillary incisors and the lingual side of mandibular anterior teeth (P<0.05). Alveolar bone height in the anterior tooth region decreases after orthodontic treatment for Angle's Class II division 1 malocclusion, being closely related to tooth position together with movement direction and amplitude.

Vertical ridge augmentation of atrophic posterior mandible with corticocancellous onlay symphysis graft versus sandwich technique: clinical and radiographic analysis.

Alveolar ridge augmentation of atrophic posterior mandibular ridge represents a challenge in oral and maxillofacial surgery to restore aesthetic and function. The aim of the study was to compare the clinical and radiographic outcomes of bone formation in atrophic posterior mandibles augmented using onlay symphysis cortico-cancellous bone block with that augmented using sandwich bone augmentation technique (Inlay). Twelve patients were selected with missing mandibular posterior teeth. CBCT were done for all patients preoperatively to assess the residual bone height, ranged between 5 and 7mm from the inferior alveolar nerve with adequate sufficient alveolar ridge width more than 4mm. Patients required bone augmentation procedure with autologous onlay chin graft (group I) versus those used as inlay sandwich technique (group II). Clinical and radiographic analysis were done to analyses the newly formed bone and bone height. Percent of change in bone height was also calculated and revealed that group I was higher than group II, however, statistically insignificant differences between the two groups were found regarding the percentage of newly formed bone. Vertical ridge augmentation procedures using onlay chin graft took lesser time than the interpositional grafting with fixation technique, however, both techniques are promising for vertical ridge augmentation.

A Comparative Study Evaluating the Effects of Crestal Bone Change Following Immediate and Delayed Implant Placement

For the rehabilitation of the single-tooth space, a number of prosthodontic techniques have been known and are well established. Fixed and removable partial dentures being the easiest are associated with the major drawbacks of loss of tooth structure and vitality. Though replaced by implant supported rehabilitations, crestal bone loss has been reported as the one of the major factor affecting the long term prognosis. Thus the main aim of the study was to assess and compare the reverberations of immediate and delayed placement of implant on crestal bone height. Material and methodology: 30 patients aged between 18-60 years were selected on the basis of inclusion criteria and divided randomly into two groups of 15 each. In Group A immediate implant placement was done while in Group B delayed implant placement was done. In both the groups, Crestal bone height (Buccolingual width + interproximal height), keratinized mucosa index, Jemt papilla fill index, Plaque index, Gingival index and Periodontal attachment levels were analyzed at baseline, after 3, 6 and 12 months. Results: The parameters were recorded and analyzed statistically. Categorical values were analyzed using mean, frequency and percentage while descriptive analysis was done using student t test. It was observed that mean changes in crestal bone height, papilla filled index, periodontal attachment levels, gingival and plaque index was statistically significant in both the groups from baseline to 12 months, while keratinized mucosa index represented no change between the two groups. Conclusion: The study came to the conclusion that placing an immediate implant rather than a delayed should be significantly preferred. Though in immediate implant placement, crestal bone is preserved and gingival architecture is prevented from collapsing along with time of treatment, preservation of aesthetics and patient comfort being the other major advantages. Keywords: Aesthetics, Crestal Bone Height, Delayed Implant, Extraction Socket, Immediate Implant, Periodontal Parameters.

A Randomised Clinical Study of the Effect of a Denture Soft Liner on Mandibular Ridge Resorption in Complete Denture Wearers After One and Two Years Of Denture Insertion

Abstract: Aim: The aim of this study was to assess the effect of soft denture liners on mandibular ridge resorption in complete denture wearers after two years of use. Methodology: The study included 32 patients ranging in age from 35 to 65 years old. Those patients were completely edentulous with well formed ridges, Class I relation and no medical problem. Thirty two selected patients were divided into two groups, namely Experimental group and Control group. Control group (n = 16, 8 males and 8 females) received conventional maxillary and mandibular complete dentures. Whereas in Experimental group, (n = 16, 8 males and 8 females) silicone lined lower complete denture were made. Three panoramic radiographs (orthopantomogram [OPG]) were taken for each participant to assess the amount of bone resorption; immediately, one year, and two years after denture insertion. For comparing two groups at three different time intervals, analysis of variance (ANOVA) two way with post-hoc tests was used. A statistically significant pvalue of less than 0.05 was considered. Results: After denture delivery, there was significant change in bone height in all patients ( p &lt; 0.001) . The comparison of bone height between the two groups in different regions at different time intervals revealed a significant difference in bone levels at baseline to one year and baseline to two years. However, Experimental group experienced 50% less bone loss than control group over a two-year period. Conclusion: Based on the findings of the current study, it can be inferred that use of soft liners helps in reducing residual ridge resorption significantly when compared with conventional denture material.

Comparison of Implant Success Rate Between Direct And Indirect Sinus Lift Procedure

Objective: The objective of the study is to compare gain in bone height and post-operative complications e with direct and indirect sinus lift procedure. Methods: This prospective clinical study was conducted at the department of Science of Dental Materials, University Medical and Dental college Faisalabad, in a period of one year from November 2021 to November 2022. For patients in the 20-50 years age range either gender with maxillary posterior edentulous regions but with a low sinus and deficient alveolar ridge, implant retained prostheses would be a viable option. Results: Results showed that pain and gingival inflammation resolved at 1st week postoperatively. These two parameters frequency was higher in patients with indirect method as compared to patients who were treated with direct method. Swelling was also settled in both treatment groups after 1st week postoperatively. However, frequency of swelling was higher in indirect method as that of direct method but the difference was not statistically significant. There is significant change in bone height postoperatively in both treatment groups. But gain in mean bone height was significantly higher in patients treated with direct approach. Conclusion: This study did not find a significant difference between direct versus indirect sinus lift procedures in terms of swelling, inflammation, and pain following surgery. Indirect sinus lifts, however, result in a significantly lower bone height gain than direct sinus lifts. Â Key Words: Edentulism, Sinus lift procedures, Direct, Indirect, Bone height, Sinus surgery.

Incisors' bone height and inclination changes after orthodontic treatment with a self-ligating passive system.

This study aimed to evaluate changes in the alveolar buccal bone height of maxillary and mandibular incisors after orthodontic treatment with a self-ligating passive system and to assess the correlation between bone height and incisor inclination. Pre (T1) and post-treatment (T2) cone-beam computed tomography images of patients treated with the Damon 3MX appliance system were measured to quantify the alveolar buccal bone height of the maxillary incisors. The incisor's inclination was measured in digital models. Paired t-test was used to evaluate the changes between T1 and T2, and Pearson's coefficient was used to test the correlation. All teeth presented statistically significant alveolar buccal bone loss at T2. A statistically significant buccal inclination was observed only for the lower left lateral incisors. There was no correlation between bone height changes and incisor inclination. Orthodontic treatment with a self-ligating passive system showed changes in alveolar height, but these changes were not correlated with incisor inclination. Key words:Passive self-ligating brackets, orthodontics, corrective, treatment outcome, alveolar bone loss.

Effect of implant diameter and cantilever length on the marginal bone height changes and stability of implants supporting screw retained prostheses: A randomized double blinded control trial.

This randomized controlled trial aimed to evaluate the effect of implants' two different diameters and cantilever lengths on the marginal bone loss and stability of mplants supporting maxillary prostheses. Ninety-six implants were placed in sixteen completely edentulous maxillary ridges. Patients were randomly divided into two groups: Group A, implants were placed with a cantilever to anterior-posterior AP spread length (CL:AP) at a ratio of 1:3; Group B, implants were placed with a CL:AP at a ratio of 1:2. Patients were further divided into four sub-groups: Groups A1, A2, B1, and B2. Groups A1 and B1 received small diameter implants while Groups A2 and B2 received standard diameter implants. Bone height and stability measurements around each implant were performed at 0, 4, 8 and 24 months after definitive prostheses delivery. Statistical analysis of the mean implant stability and height values revealed an insignificant difference between Group A1 and Group A2 at all the different time intervals while significantly higher values in Group B1 in comparison with Group B2. Results also showed significantly higher values in Group A1 in comparison with Group B1 and an insignificant difference between Group A2 and Group B2 at all the different time intervals. It can be concluded that the use of small diameter implants placed with a CL:AP at a ratio of 1:3 provided predictable results and that the 1:2 CL:AP significantly induced more critical bone loss in the small diameter implants group, which can significantly reduce long term success and survival of implants.

Assessment of Bone Height Changes Based on the Cone-Beam Computed Tomography Following Intentional Replantation for Periodontally Compromised Teeth.

Background and Objectives; This study aimed to evaluate the clinical outcomes and bone changes before and after intentional replantation (IR) for periodontally compromised teeth by using cone-beam computed tomography (CBCT). Materials and Methods; Fourteen periodontally involved teeth were selected for IR. A preoperative orthodontic procedure was performed to apply luxation, and the tooth was then gently extracted. Retrograde filling of the root-end canal was performed. Once the tooth was repositioned in the socket, it was splinted with the adjacent tooth. After three months, prosthetic restoration was performed. Results; Clinical parameters and CBCT images were obtained before and after the IR procedure. The height of the alveolar bone was measured on the CBCT images by using software. Most preoperative symptoms, including pain, mobility, probing depth (PD) and bleeding on probing (BOP), significantly decreased after IR (pain: 4.71 to 1.00; mobility: 1.36 to 0.29; PD: 5.60 to 2.85; BOP: 3.50 to 0.79). CBCT analysis indicated an increase in bone height after IR (the amount of change: maxilla, 4.00; mandible, 1.95). Conclusions; A previous study reported that IR for periodontally involved teeth is quite limited. However, in this study, IR of periodontally compromised teeth showed favorable results in clinical and radiographic evaluations, suggesting that IR may be an alternative to extraction of teeth with periodontal disease.

Changes in sinus mucosal thickening in the course of tooth extraction and lateral sinus augmentation with surgical drainage: A cone-beam computed tomographic study.

The objective of the study was to evaluate the radiographic changes in sinus mucosal thickness (SMT) in patients with mucosal thickening of odontogenic origin after maxillary molar extraction and lateral sinus augmentation with simultaneous surgical drainage and implant placement. Forty-six patients were included in this study. The changes in SMT were evaluated using cone-beam computed tomography images produced at four time points: before extraction (T0), before surgery (T1), immediately after surgery (T2), and after prosthesis delivery (T3), and statistical differences between time points were analyzed. The changes in SMT and augmented bone height (ABH) regarding the reason of extraction, smoking, ostial patency, and the presence of postoperative sinusitis were also evaluated. Over time points, SMT gradually decreased (T0: 19.44 ± 9.22 mm, T1: 15.10 ± 8.89 mm, T2: 8.42 ± 6.01 mm, and T3: 4.16 ± 4.91 mm) (p < .05). Five out of 6 patients with ostial obstruction at T1 presented ostial patency at T3. Two patients developed postoperative sinusitis but recovered with medication. Ostial patency at T1, SMT at T1, and reason of extraction did not statistically significantly influence SMT at T3. SMT at T1 had no statistically significant impact on ABH change between T2 and T3. Sinus mucosal thickness was gradually reduced by extraction of compromised teeth and drainage during lateral sinus augmentation. The drainage contributed more to the reduction in SMT.

Introduction of Accurate Measurement of the Alveolar Bone Height in Bone Grafting Area after Sinus Lift.

Sinus lift via the alveolar crest approach has been proven to solve inadequate alveolar bone height perfectly in the posterior region of the maxilla. Nevertheless, the surgical area cannot be directly observed, imaging methods are necessary to reveal whether the surgery has achieved the expected results. Cone-Beam Computed Tomography (CBCT) images are usually taken before surgery and at the completion of final pre-repair osseointegration and evaluate the effect of maxillary sinus lift by measuring the alveolar bone height in the bone graft area. However, there is no uniform and recognized method to accurately measure the alveolar bone height in the bone grafting area before and after maxillary sinus lift. Therefore, the authors propose a simple, accurate, and reproducible method for the measurement of alveolar bone height in maxillary sinus lift on CBCT, which will be an innovation. 30 implant cases (30 patients) were included in this study. The authors create a uniformed measurement surface in the CBCT axial interface to ensure consistency at the completion of final prerepair osseointegration and before surgery. Then changes in alveolar bone height in the bone grafting area before and after sinus lift were measured on CBCT coronal and arch planes. Finally, for the purpose of verification of repeatability, three dentists from our department were randomly selected to measure and record the above CBCT data at three different time points. The data showed that in the CBCT measurements of the three dentists, neither the coronal plane nor the arch plane was statistically significant. (P > 0.05). This measurement method is simple, accurate and repeatable. It can be applied to measure alveolar bone height in the bone grafting area before and after maxillary sinus lift.

Comparison between bone height changes around the splinted and non-splinted OT bridge system implants in edentulous mandibles rehabilitated with all-on four full arch prosthesies a randomized clinical trial

Objectives: the aim of this study was to compare the difference in marginal bone loss around the splinted and non-splinted implants supported on OT bridge system in full arch implant mandibular restoration using the All-On -Four concept. Materials and methods: This study was conducted on 12 completely edentulous patients having 48 implants. All patients were treated with a mandibular implant supported fixed restoration. Four implants were placed interforaminally for each patient and restored with immediately loaded restoration following the All-On-Four concept. Comparison was made between the splinted implants and non-splinted implants of immediately loaded temporary conversion prosthesis using OT bridge system regarding the marginal bone loss (MBL) using digital periapical radiograph at base line and after 3 months. Results: The marginal bone loss around both groups splinted and non-splinted implants after 3 months of immediate loading was similar with no statistically significant difference. Conclusion: Both techniques are considered as reliable methods for immediate loading of a full arch screw retained implant restoration with no preference of one approach regarding marginal bone loss around implants.

Periodontal Health and Marginal Bone Height Change around Abutments in Zirconia versus Cobalt-Chromium Bar Retained Mandibular Tooth Supported Overdenture: A Randomized Controlled Clinical Trial

Periodontal Health and Marginal Bone Height Change around Abutments in Zirconia versus Cobalt-Chromium Bar Retained Mandibular Tooth Supported Overdenture: A Randomized Controlled Clinical Trial

Platelet rich plasma or platelet rich fibrin: which is better in post extraction immediate implant placement followed by immediate loading?

&lt;p class="abstract"&gt;&lt;strong&gt;Background: &lt;/strong&gt;The study aimed to compare the clinical efficacy of platelet rich plasma (PRP) and platelet rich fibrin (PRF) used with phosphosilicate putty during immediate post extraction implant placement and immediate loading.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; A prospective comparative clinical study was conducted on 20 adults. Two groups were made with 10 patients in each by random selection. Each patient required tooth extraction and replacement with immediate implantation and immediate loading. In Group 1 PRP was prepared from the patient's blood, mixed with alloplastic graft, and packed in peri-implant space and similarly in Group 2 PRF was prepared from the patient's blood and mixed with alloplastic graft in peri-implant space. All the patients were evaluated for postoperative pain, soft tissue analysis, implant mobility, and crestal bone height changes were observed for up to 6 months, using paired/independent t-test, and Chi-square test.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; It was seen that for pain on 1st postop day Group 1 had shown superior results than Group 2 after 7 days both groups showed good soft tissue healing. No significant difference was found in both groups when seen for implant mobility. The difference in crestal bone height gain in the first 3 months of Group 2 showed a remarkable height gain than in Group 1. And at 6th month overall crestal height gain difference between both groups was non-significant.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;The autologous PRF can present new possibilities for enhanced healing and functional recovery over PRP during immediate post extractive implantation and immediate loading.&lt;/p&gt;

Association between alveolar bone height changes in mandibular incisors and three-dimensional tooth movement in non-extraction orthodontic treatment with Invisalign.

The purpose of this study was to investigate associations between alveolar bone height changes on the labial and lingual sides in mandibular incisors and three-dimensional orthodontic tooth movement, involving apex displacement, tooth inclination, and angulation. The samples consisted of 43 adult patients treated with Invisalign aligners. All subjects were skeletal Class I patients without extraction in mandible. Pre-treatment and post-treatment cone-beam computed tomographic images were obtained to measure labial and lingual alveolar bone height and bone thickness at apex level in four mandibular incisors. An x, y, z coordinate system, superimposing on mandibular body, was established to analyse three-dimensional apex movement and tooth inclination and angulation changes. Multiple linear regression was applied to identify the determining factors of marginal bone changes during orthodontic treatment. Three directions of apex movement (anteroposterior, vertical, transverse) significantly associated with alveolar bone height changes. Inclination changes had a strong effect on lingual marginal bone, while tooth angulation had no significant effect on alveolar bone height. Incisors with lingual bodily movement were more susceptible to lingual marginal bone recession compared with lingual tipping movement. Alveolar bone height changes on the labial and lingual sides were associated with three-dimensional apex movement, inclination changes, and movement patterns. Appropriate tooth movement should be considered to avoid excessive marginal bone loss around mandibular incisors.