Determination of orthodontic tooth movement and tissue reaction following demineralized freeze-dried bone allograft grafting intervention

Orthodontic tooth movement after periodontal regeneration of intrabony defects

The prevalence of intrabony defects in patients with advanced periodontitis stages III and IV is high. These patients usually need both periodontal treatment and orthodontic therapy, including tooth movement through bone defects, to improve masticatory function, aesthetics, and overall quality of life. Clinical practice guidelines recommend periodontal regenerative surgical interventions to resolve these defects and propose initiating orthodontic tooth movement (OTM) once periodontal therapy goals have been met. Surgical interventions using various regenerative technologies like barrier membranes and enamel matrix proteins, combined or not with bone replacement grafts, have proven effective in regenerating lost periodontal tissues. However, the combination of periodontal and orthodontic treatments requires consideration of how periodontal regenerative therapies influence OTM. Studies suggest that regenerated bone may differ in density, composition, vascularity, and cellular activity, potentially affecting the speed and efficiency of OTM, and potential root resorption of moved teeth. Understanding the sequence and timing of implementing OTM after regenerative periodontal interventions is crucial due to their interlinked processes of bone resorption and formation. This narrative review aims to uncover scientific evidence regarding these combined treatments, examining the impacts of different regenerative technologies on OTM and delineating their advantages, limitations, and best practices.

Impact of Bone-Grafting Materials on the Rate of Orthodontic Tooth Movement: A Systematic Review

Orthodontists may encounter patients with alveolar bony defects, which are often treated with various bone-grafting materials. The effects of different bone-grafting materials on orthodontic tooth movement (OTM) are of concern to orthodontists. Therefore, we aimed to evaluate the current status of the literature that reports on the effects of different bone-grafting materials on OTM in terms of the rate and side effects. An electronic search of the PubMed and Scopus databases and Google Scholar was performed. Two reviewers independently conducted the screening process using COVIDENCE™, and a third reviewer resolved any conflicts. SYRCLE's (Systematic Review Centre for Laboratory Animal Experimentation's) risk-of-bias tool for animal studies was utilized to assess the quality of the included studies. Out of 457 initial titles, 11 studies were finally included for data extraction. All of the included studies were animal experiments, and none of them were considered to have a low risk of bias. The included studies had varied results. However, a general tendency existed, whereby OTM in surgically treated areas with no bone grafting presented the highest OTM rate. In cases where a bone graft was used, xenografts revealed the highest OTM rate, followed by alloplasts. Lastly, the use of allografts resulted in the slowest OTM rates. The most common side effect was root resorption. In conclusion, there is a lack of high-quality evidence regarding the effects of bone-grafting materials on OTM rate. Due to the lack of human subjects, RCTs, and the heterogeneity of subjects in the current literature, the impact of bone-grafting materials on OTM deserves further investigations using more rigorous scientific methodologies.

Impact of Frontier Development of Alveolar Bone Grafting on Orthodontic Tooth Movement

Sufficient alveolar bone is a safeguard for achieving desired outcomes in orthodontic treatment. Moving a tooth into an alveolar bony defect may result in a periodontal defect or worse–tooth loss. Therefore, when facing a pathologic situation such as periodontal bone loss, alveolar clefts, long-term tooth loss, trauma, and thin phenotype, bone grafting is often necessary to augment bone for orthodontic treatment purposes. Currently, diverse bone grafts are used in clinical practice, but no single grafting material shows absolutely superior results over the others. All available materials demonstrate pros and cons, most notably donor morbidity and adverse effects on orthodontic treatment. Here, we review newly developed graft materials that are still in the pre-clinical stage, as well as new combinations of existing materials, by highlighting their effects on alveolar bone regeneration and orthodontic tooth movement. In addition, novel manufacturing techniques, such as bioprinting, will be discussed. This mini-review article will provide state-of-the-art information to assist clinicians in selecting grafting material(s) that enhance alveolar bone augmentation while avoiding unfavorable side effects during orthodontic treatment.

Development of root resorption during orthodontic tooth movement after cleft repair using different grafting materials in rats

OBJECTIVE

The aim of the present study was to investigate the influence of three grafting materials for cleft repair on orthodontic tooth movement in rats.

MATERIALS AND METHODS

Artificial alveolar clefts were created in 21 Wistar rats and were repaired 4 weeks later using autografts, human xenografts and synthetic bone substitute (beta-tricalcium phosphate/hydroxyapatite [β-TCP/HA]). A further 4 weeks later, the first molar was moved into the reconstructed maxilla. Microfocus computed tomography (μCT) was performed six times (T0-T5) to assess the tooth movement and root resorption. After 8 weeks, the affected reconstructed jaw was resected for histopathological investigation.

RESULTS

Total distances reached ranged from 0.82 ± 0.72 mm (β-TCP/HA) to 0.67 ± 0.27 mm (autograft). The resorption was particularly determined at the mesiobuccal root. Descriptive tooth movement slowed and root resorption increased slightly. However, neither the radiological changes during tooth movement (µCT T1 vs. µCT T5: autograft 1.85 ± 0.39 mm³ vs. 2.38 ± 0.35 mm³, p = 0.30; human xenograft 1.75 ± 0.45 mm³ vs. 2.17 ± 0.26 mm³, p = 0.54; β-TCP/HA: 1.52 ± 0.42 mm³ vs. 1.88 ± 0.41 mm³, p = 0.60) nor the histological differences after tooth movement (human xenograft: 0.078 ± 0.05 mm²; β-TCP/HA: 0.067 ± 0.049 mm²; autograft: 0.048 ± 0.015 mm²) were statistically significant.

CONCLUSION

The autografts, human xenografts or synthetic bone substitute used for cleft repair seem to have a similar effect on the subsequent orthodontic tooth movement and the associated root resorptions.

CLINICAL RELEVANCE

Development of root resorptions seems to have a secondary role in choosing a suitable grafting material for cleft repair.

Bone Graft Materials for Alveolar Bone Defects in Orthodontic Tooth Movement

Clinically, orthodontic tooth movement (OTM) across the narrow alveolar ridge area inevitably entails some adverse reactions such as limited movement and periodontal tissue damage. Hence, it is essential to reconstruct the morphology of the alveolar crest before the tooth movement. Unlike the routine reconstruction of alveolar ridge in the field of implant, the orthodontic practices are distinctive, which require dental movement across the constructed alveolar ridge with safety and stability. Herein, we addressed the pros and cons of reconstruction of the defected orthodontic alveolar ridge with different bone graft materials. Attention is also paid to other factors such as the postgraft initiation time of OTM that can substantially influence the bone reconstruction and tooth movement effect. Rather, considering the lack of a unified standard in orthodontic clinics related to bone reconstruction for OTM, we provide some recommendations and guidance for OTM through alveolar ridge defect area.

The impact of alloplast and allograft on bone homeostasis: Orthodontic tooth movement into regenerated bone

BACKGROUND

The aim of the study is to examine bone healing following augmentation with allograft or β-tricalcium phosphate (β-TCP) and evaluate orthodontic tooth movement (OTM) into the augmented sites.

METHODS

The study included two parts. Part I included the alveolar bone regeneration model. Osseous defects were created by extraction of the maxillary first molars in C57BL/6 mice, and the sockets were filled with allograft, β-TCP, or left unfilled (n = 6/group). Mouse allograft was prepared by a novel method using long bones. Maxillae were collected at 2, 4, and 6 weeks for microcomputed tomography (μCT) and histological analysis. In Part II, OTM was performed after full bone healing, through grafted and unfilled sockets (n = 10/group), and the second molar shift was assessed using μCT.

RESULTS

Bone volume and trabeculation were reduced in β-TCP compared with allograft and non-grafted groups at 2 and 4 weeks post-grafting, but similar at 6 weeks. Graft particles could be detected at 2 weeks post-grafting for β-TCP, and at 2 and 4 weeks for allograft. Increased osteoclasts' presence was observed in the β-TCP group at 2 and 4 weeks compared with allograft and control. OTM was similar in the two graft groups, but impaired versus the non-grafted controls.

CONCLUSION

β-TCP and allograft induce full normal healing but alter OTM into the regenerated sites.

BMP2-Functionalized Biomimetic Calcium Phosphate Graft Promotes Alveolar Defect Healing During Orthodontic Tooth Movement in Beagle Dogs

Background: Grafting of biomaterial in alveolar defect facilitates bone healing and orthodontic treatment. BMP2-functionalized biomimetic calcium phosphate (BioCaP) graft had shown excellent bone defect healing potential in many preclinical studies. In this study, we aimed to investigate the influence of BioCaP graft on surgical alveolar bone defect healing during orthodontic tooth movement (OTM) in beagle dogs.

Methods: Nine Beagle dogs were randomly assigned to three groups: control, deproteinized bovine bone (DBB), and BioCaP. The maxillary second premolars were protracted into the defects of the extracted maxillary first premolar for 8 weeks. The rate of OTM, alveolar remodeling and bone defect healing were evaluated by histology, histomorphometry, and cone beam computed tomography (CBCT) imaging. Periodontal probing depth was analyzed. Gingival cervicular fluid was collected at week 4 and 8, and the IL-1β level was measured by ELISA.

Results: The histological sections of the bone defect showed more newly formed bone in the BioCaP group. The percentage of new bone formation in the BioCaP group was 1.61-, and 1.25-fold higher compared to the control and DBB group, respectively. After 8 weeks of OTM, the resorption rate of BioCaP was 1.42-fold higher compared to DBB. The root resorption index in the DBB group was 1.87-, and 1.39-fold higher compared to the control and BioCaP group, respectively. CBCT images showed 1.92-, and 1.36-fold higher bone mineral density in the BioCaP group compared to the control and DBB group, respectively. There was no significant difference in OTM among the three groups. The distance between the enamel cementum and the crest of the alveolar ridge in the control group was 1.45-, and 1.69-fold higher compared to DBB and BioCaP group, respectively. Periodontal probing depth at week 8 was reduced in the BioCaP group compared to the control. IL-1β concentration in the gingival cervicular fluid was significantly lower in the BioCaP group compared to the control group at week 4 and 8.

Conclusion: BioCaP graft robustly promoted bone regeneration and alveolar bone defect healing without affecting OTM. BioCaP graft caused less alveolar bone recession and root resorption of traction tooth with favorable periodontal attachment level indicating that BioCaP as a bioactive and functional bone filling material for alveolar bone defects during orthodontic treatment.

Management of Bilateral Mandibular Fused Teeth

Tooth fusion is a developmental dental anomaly that may affect both the deciduous and permanent dentition. Such anomalies may cause problems such as caries, periodontal disease or even esthetic impairments, which will require intervention. In the present case, a young patient was referred to the periodontal clinic for management of bilateral mandibular fused teeth as part of the orthodontic treatment. On the lower right, the teeth involved were incompletely fused involving only the cervical region. On the lower left, the two teeth were completely fused from the crown to the apex. A surgical resection was carried out on the fused teeth on the right, while the fused teeth on the left was undisturbed. Orthodontic treatment was later carried out to align both the upper and lower arch. The patient was satisfied with treatment outcome.

Microarchitecture and Biomechanical Evaluation of BoneCeramic Grafted Alveolar Defects during Tooth Movement in Rat

OBJECTIVE

BoneCeramic can regenerate bone in alveolar defects, but it remains unknown whether it is feasible to move a tooth through BoneCeramic grafting sites. The objective of this study was to investigate three-dimensional real-time bone responses and micromechanical properties in the grafting sites during orthodontic tooth movement.

METHODS

Sixty 5-week-old rats were randomly assigned into three groups to receive BoneCeramic, natural bovine cancellous bone particles (Bio-Oss), and no graft, respectively, after the extraction of the left maxillary first molar. After 4 weeks, the maxillary left second molar was moved into the extraction for 28 days. Dynamic bone microstructures and root resorption were evaluated using in vivo micro-computed tomography and histology. Stress distribution of tooth roots and biomechanical properties of corresponding bone tissue were examined by finite element methods and nanoindentation. Mixed-model analysis of variance was performed to compare the difference among time points with Bonferroni post hoc tests at the significance level of P < .05.

RESULTS

The BoneCeramic group had the least amount of tooth movement and root resorption volume and craters, highest bone volume fraction, trabecular number, mean trabecular thickness, microhardness, and elastic modulus, followed by Bio-Oss and the control group. The highest stress accumulated in the cervical region of the mesial roots.

CONCLUSION

BoneCeramic has better osteoconductive potential and biomechanical properties and induces less root resorption compared with Bio-Oss grafting and naturally recovered extraction site.

Human tooth-derived biomaterial as a graft substitute for hard tissue regeneration

Aim: The present study was conducted to evaluate the efficacy of human dentine grafts for new bone augmentation. Materials & methods: Dentine grafts (demineralized dentine matrix [DDM] and mineralized dentine matrix [MDM]) were prepared and implanted in rats. Tetracycline was administered twice. Paraffin and resin sections were prepared from the harvested grafts and stained respectively with hematoxylin and eosin (in addition to tartrate acid phosphatase for osteoclasts) and Villanueva. The new bone formation (bone thickness, mineral apposition rate and the bone formation rate) was analyzed in tetracycline-labeled resin sections. Results & conclusion: DDM grafts implanted in bone were better able to augment the bone compared to MDM grafts. However, both MDM and DDM failed to induce new bone in ectopic site, they could be considered as alternative autograft substitutes after protocol optimization.

BoneCeramic graft regenerates alveolar defects but slows orthodontic tooth movement with less root resorption

INTRODUCTION

BoneCeramic (Straumann, Basel, Switzerland) can regenerate bone in alveolar defects after tooth extraction, but it is unknown whether it is feasible to move a tooth through BoneCeramic grafting sites. The objective of this study was to investigate 3-dimensional real-time root resorption and bone responses in grafted sites during orthodontic tooth movement.

METHODS

Sixty 5-week-old rats were randomly assigned to 3 groups to receive BoneCeramic, natural bovine cancellous bone particles (Bio-Oss; Geistlich Pharma, Wolhusen, Switzerland), or no graft, after the extraction of the maxillary left first molar. After 4 weeks, the maxillary left second molar was moved into the extraction site for 28 days. Dynamic bone microstructures and root resorption were evaluated using in-vivo microcomputed tomography. Stress distribution and corresponding tissue responses were examined by the finite element method and histology. Mixed model analysis of variance was performed to compare the differences among time points with Bonferroni post-hoc tests at the significance level of P <0.05.

RESULTS

The BoneCeramic group had the least amount of tooth movement and root resorption volumes and craters, and the highest bone volume fraction, trabecular number, and mean trabecular thickness, followed by the Bio-Oss and the control groups. The highest stress accumulated in the cervical region of the mesial roots.

CONCLUSIONS

BoneCeramic has better osteoconductive potential and induces less root resorption compared with Bio-Oss grafting and naturally recovered extraction sites.

Effect of nanocrystalline hydroxyapatite socket preservation on orthodontically induced inflammatory root resorption

Objective

Orthodontically induced inflammatory root resorption (OIIRR) is considered to be an important sequel associated with orthodontic tooth movement (OTM). OTM after Socket preservation enhances the periodontal condition before orthodontic space closure. The purpose of this study is to investigate the histologic effects of NanoBone®, a new highly nonsintered porous nano-crystalline hydroxyapatite bone on root resorption following OTM.

Materials and Methods

This experimental study was conducted on four male dogs. In each dog, four defects were created at the mesial aspects of the maxillary and mandibular first premolars. The defects were filled with NanoBone®. We used the NiTi closed coil for mesial movement of the first premolar tooth. When the experimental teeth moved approximately halfway into the defects, after two months, the animals were sacrificed and we harvested the area of interest. The first premolar root and adjacent tissues were histologically evaluated. The three-way ANOVA statistical test was used for comparison.

Results

The mean root resorption in the synthetic bone substitute group was 22.87 ± 11.25×10^-4mm² in the maxilla and 21.41 ± 11.25×10^-4mm² in the mandible. Statistically, there was no significant difference compared to the control group (p>0.05).

Conclusion

The use of a substitution graft in the nano particle has some positive effects in accessing healthy periodontal tissue following orthodontic procedures without significant influence on root resorption (RR). Histological evaluation in the present study showed osteoblastic activity and remodeling environment of nanoparticles in NanoBone®.

Tooth movement out of the bony wall using augmented corticotomy with nonautogenous graft materials for bone regeneration

This prospective randomized split-mouth study was performed to compare the effects of augmented corticotomy with those of different nonautogenous bone graft materials combined with orthodontic tooth movement in dogs. Decortication was performed on the buccal bone surface of 6 male beagle dogs that were randomly assigned to receive grafts of deproteinized bovine bone mineral, irradiated cortical bone, or synthetic bone. Immediate orthodontic force was applied to the second and third premolars for buccal tipping for 6 weeks. The pocket depth and width of keratinized tissue (WKT) were measured. Histologic and histomorphometric analyses were performed. The probing depth, WKT, and ratio of the area of new bone to that of total bone on the buccal side were not significantly different between groups. All groups had considerable new bone formation on the pressure side. New bone formation on the buccal side and buccal plate formation in the coronal direction along the root surfaces were induced by the bone-derived and PDL-derived mesenchymal matrix, respectively. The angular change between groups was significantly different (P < 0.001). Augmented corticotomy using nonautogenous graft materials facilitated tooth movement without fenestrations and accelerated new bone formation on the pressure side.

Timing of force application affects the rate of tooth movement into surgical alveolar defects with grafts in beagles

INTRODUCTION

The purpose of this study was to investigate the influence of the timing of orthodontic force application on the rates of orthodontic tooth movement into surgical alveolar defects with bone grafts in beagle dogs.

METHODS

Twelve beagles were randomly divided into 2 groups according to the surgical procedure: alveolar osteotomy alone (control) or osteotomy with bone graft (experimental group). The maxillary second premolars were protracted for 6 weeks into the surgical sites: immediately, at 2 weeks, and at 12 weeks after surgery. The orthodontic tooth movement rates and alveolar remodeling concomitant with surgical defect healing were evaluated by model measurements and histomorphometry as well as microcomputed tomography and histology. One-way analysis of variance and the Scheffé post hoc comparison were performed for investigating the rates of orthodontic tooth movement and mineralized bone formation.

RESULTS

Both the orthodontic tooth movement rate and the mean appositional length of mineralized bone in the tension side of teeth were significantly accelerated when force was applied at 2 weeks in the control group and immediately in the experimental group (P <0.001). The 2-week control group showed a dramatic increase in apposition rate during 4 to 6 weeks after force application, whereas the immediate protraction experimental group did within the first 3 weeks (P <0.001). Decreased orthodontic tooth movement rates and reduced bone remodeling activities were apparent in the 12-weeks groups, especially in nongrafted defects.

CONCLUSIONS

A bone graft into the surgical defect can not only allow immediate force application for accelerating orthodontic tooth movement with favorable periodontal regeneration, but also decrease the risk of inhibited orthodontic tooth movement in case of delayed force application after surgery.

Periodontal parameters following orthodontic treatment in patients with aggressive periodontitis: A before-after clinical study

BACKGROUND

The success of combined periodontal and orthodontic approach in the treatment of aggressive periodontitis patients with the pathologic extruded anterior teeth is a main concern and stability of the treatment results is an important factor to evaluate the treatment. The present study investigated the periodontal parameters at the end of the orthodontic treatment in patients with the aggressive periodontitis.

MATERIALS AND METHODS

Eight patients with an aggressive periodontal disease, extruded maxillary incisors, infrabony defects and probing depth of ≥5 mm were enrolled in this clinical trial (before, after). After periodontal therapy, orthodontic treatment was carried out for intrusion and alignment of teeth. Plaque index (PI), probing pocket depth (PPD), distance between incisal edge and interdental papilla, root length (RL), and defect dimensions (depth and width) were examined at the end of treatment and three as well as 6 months afterward. The data were subjected to repeated measure ANOVA test. P < 0.05 was considered as significant.

RESULTS

There was statistically significant decrease in PPD, PI, and depth of the defects during T0, T3 and T6 (P < 0.05). No significant differences were observed in the RL and distance between incisal edge and interdental papilla (P = 0.95). Furthermore, width of the defects demonstrated significant decrease up to T3 (P = 0.042) while no significant changes from 3 months to 6 months were noted (P = 0.59).

CONCLUSION

The results showed that combined periodontal and orthodontic approach would be a successful treatment with acceptable stability in the case of regular follow-up visits and controlled oral hygiene habits.

Clinical and biometrical evaluation of socket preservation using demineralized freeze-dried bone allograft with and without the palatal connective tissue as a biologic membrane

BACKGROUND

Alveolar ridge preservation following tooth extraction has the ability to maintain the ridge dimensions and allow the implant placement in an ideal position fulfilling both functional and aesthetic results. The aim of this study was to evaluate the efficacy of the palatal connective tissue as a biological membrane for socket preservation with demineralized freeze-dried bone allograft (DFDBA).

MATERIALS AND METHODS

Twelve extraction sites were treated with DFDBA with (case group) and without (control group) using autogenous palatal connective tissue membrane before placement of implants. Alveolar width and height, amount of keratinized tissue, and gingival level were measured at pre-determined points using a surgical stent at two times, the time of socket preservation surgery.

RESULTS

In both groups a decrease in all socket dimensions was found. The average decrease in socket width, height, keratinized tissue, and gingival level in case group was 1.16, 0.72, 3.58, and 1.27 mm, and in control group was 2.08, 0.86, 4.52, and 1.58 mm respectively. Statistical analysis showed that decrease in socket width (P = 0.012), keratinized tissue (P ≤ 0.001), and gingival level (P = 0.031) in case group was significantly lower than that of the control group. Results showed no meaningful difference in socket height changes when compared with case and control groups (P = 0.148).

CONCLUSION

Under the limits of this study, connective tissue membrane could preserve socket width, amount of keratinized tissue, and the gingival level more effectively than DFDBA alone.