Modeling of trabecular bone and lamina dura following selective alveolar decortication in rats

Immediate orthodontic treatment after regeneration of periodontal intrabony defects: A long-term retrospective study

BACKGROUND/PURPOSE

Orthodontic movement is often necessary for periodontally compromised patients to enhance esthetics, function, and long-term occlusal stability. However, the impact of orthodontic treatment immediately following the regeneration of intrabony defects on periodontal healing remains a topic of debate. The objective of this long-term case series study was to test the hypothesis that orthodontic treatment performed immediately after regenerative procedures for periodontal intrabony defects did not adversely affect periodontal healing.

MATERIALS AND METHODS

This case series study involved nine periodontally compromised subjects with a total of 17 intra-bony defects. Orthodontic brackets were applied immediately before surgery. Flaps were raised, and diseased roots were debrided. All intra-bony defects were filled with alloplastic bone grafts and covered with resorbable membranes, except for one defect treated with Emdogain. All patients initiated orthodontic treatment immediately after periodontal regenerative surgery. Clinical parameters, including probing depth, attachment level, and bone fill, were assessed at baseline and during final maintenance therapy.

RESULTS

The mean follow-up duration was 12.8 years. None of the 17 surgically regenerated teeth were lost. The mean reduction in probing depth was 3.94 mm (95% confidence level, 3.19-4.68; P < 0.001), with a mean clinical attachment gain of 3.47 mm (95% confidence level, 2.90-4.03; P < 0.001). The mean radiographic bone fill was 4.89 mm (P < 0.001).

CONCLUSION

Based on the findings of this long-term case study, it can be concluded that immediate orthodontic treatment does not adversely affect the maturation process of periodontal regeneration outcomes and can be maintained for more than ten years.

Safety and accuracy assessment of static computer assisted localized piezoelectric alveolar decortication: an in vitro study

OBJECTIVES

To assess the safety and accuracy of static computer assisted corticotomy surgery (sCACS) in comparison with freehand piezocision.

MATERIALS AND METHODS

A randomized in vitro study was conducted. A total of 260 interradicular corticotomies were performed in 20 identical printed models. sCACS was performed in half of the models, while the rest underwent freehand localized decortication. Accuracy was measured in the three spatial axes by overlapping the digital planning with a previous cone-beam computed tomography (CBCT) scan of the patient and a postoperative CBCT of the models. Safety was determined as the number of damaged root surfaces. Descriptive and bivariate analyses were performed.

RESULTS

Freehand corticotomies increased the likelihood of iatrogenic root damage 2.21-fold (95%CI: 1.30 to 3.77; p = 0.004). Both groups showed some degree of deviation compared to digital planning. Nevertheless, the accuracy of sCACS was significantly greater in sagittal (B = -0.21 mm, 95%CI: -0.29 to -0.12; p < 0.001), axial (B = -0.32 mm, 95%CI: -0.48 to -0.18; p < 0.001) and angular deviation (B = -2.02º; 95%CI: -2.37 to -1.66; p < 0.001) compared to freehand surgery, with the exception of depth.

CONCLUSIONS

The precision and safety of sCACS are greater than the freehand technique.

CLINICAL RELEVANCE

Corticotomies are performed in crowded areas where there is usually space limitation. Clinicians should consider the systematic use of surgical guides, since minimal deviations can cause iatrogenic root damage in areas where malocclusions are present.

The effect of single versus multiple piezocisions on the rate of canine retraction: a randomized controlled trial

BACKGROUND

Piezocision is a minimally invasive surgical method aiming to accelerate tooth movement. However, its effect was found to be transient, appertaining to the regional acceleratory phenomenon (RAP). Hence, the aim of the study was to evaluate the effect of single and multiple piezocisions on the rate of orthodontic tooth movement (OTM). Moreover, the impact of both protocols on canine tipping and orthodontically induced inflammatory root resorption (OIIRR) has been assessed.

METHODS

Thirty indicated patients for the therapeutic extraction of maxillary first premolars were enlisted in this split-mouth study, and they were randomly split into two equal groups, each including 15 subjects. In the Single Application Group (SAG), one side of the maxillary arch arbitrarily received a single piezocision before the onset of canine retraction, whereas in the Multiple Application Group (MAG), piezocisions were randomly performed on one side, three times on a monthly basis, over the 12-week study period. The contralateral sides of both groups served as the controls. Canine retraction was carried out bilaterally using nickel-titanium closed-coil springs, delivering 150 g of force, and the rate of tooth movement, as well as canine tipping were evaluated on a monthly basis, over a 3-month period. Cone-bean computed tomography scans were also conducted pre- and post- canine retraction, and OIIRR was assessed using Malmgren Index.

RESULTS

The reported outcomes revealed a significant increase in the amount of canine retraction, canine tipping, as well as root resorption scores on the experimental sides in both groups SAG and MAG post-retraction (p < 0.001). However, upon comparing the experimental sides in both groups, non-significant differences have been observed between them regarding all the assessed outcomes (p > 0.05).

CONCLUSIONS

Single and multiple piezocisions effectively accelerate OTM in comparison to conventional orthodontic treatment, with relative outcomes reported by both intervention frequencies. Accordingly, single piezocision is recommended as an adjunct to OTM. Furthermore, significant tooth tipping as well as a significantly higher root resorption risk accompanies both single and multiple piezocision applications in conjunction with OTM.

NAME OF THE REGISTRY

Clinicaltrials.gov TRIAL REGISTRATION NUMBER: NCT05782088 DATE OF REGISTRATION: 23/03/2023 "Retrospectively registered". URL: https://clinicaltrials.gov/ct2/show/NCT05782088.

Age-related alveolar bone maladaptation in adult orthodontics: finding new ways out

Compared with teenage patients, adult patients generally show a slower rate of tooth movement and more pronounced alveolar bone loss during orthodontic treatment, indicating the maladaptation of alveolar bone homeostasis under orthodontic force. However, this phenomenon is not well-elucidated to date, leading to increased treatment difficulties and unsatisfactory treatment outcomes in adult orthodontics. Aiming to provide a comprehensive knowledge and further inspire insightful understanding towards this issue, this review summarizes the current evidence and underlying mechanisms. The age-related abatements in mechanosensing and mechanotransduction in adult cells and periodontal tissue may contribute to retarded and unbalanced bone metabolism, thus hindering alveolar bone reconstruction during orthodontic treatment. To this end, periodontal surgery, physical and chemical cues are being developed to reactivate or rejuvenate the aging periodontium and restore the dynamic equilibrium of orthodontic-mediated alveolar bone metabolism. We anticipate that this review will present a general overview of the role that aging plays in orthodontic alveolar bone metabolism and shed new light on the prospective ways out of the impasse.

Accelerating the Orthodontic Treatment Using Periodontally Accelerated Osteogenic Orthodontics (PAOO): A Periodontic-Orthodontic Interrelationship

Periodontally accelerated osteogenic orthodontics (PAOO) is a periodontal-orthodontic interrelationship procedure that helps in accelerating orthodontic treatment by periodontal procedure reinforcement. This depends on the principle of the regional acceleratory phenomenon which involves inducing changes in the biology of periodontal tissues to fasten the orthodontic tooth movement by creating a surge in the osteopenic environment for tooth movement followed by bone deposition and mineralisation to stabilise the tooth in newly moved position. This PAOO involves the intentional creation of surgical corticotomy cuts followed by a grafting procedure to maintain bone resorption and thickness. Numerous modifications have been incorporated to reduce surgical complications and to improve treatment results by minimally invasive techniques. Hence, this case report incorporated piezosurgery-assisted corticotomy cuts involving the buccal side along with particulate bone grafting to fasten the orthodontic tooth movement, reducing the overall treatment time, root resorption and stabilising the orthodontic treatment results.

The effectiveness of the total-maxillary-arch-distalization approach in treating class II division 1 malocclusion: A systematic review

OBJECTIVE

The objective of this review is to assess the effect of total maxillary arch distalization (TMAD) treatment on the dental, skeletal, soft tissues, and airways during non-extraction camouflage treatment of class II division 1 patients.

METHODS

We performed a systematic review of the published data in four electronic databases up to April 2023. We considered studies for inclusion if they were examining the effects of TMAD during treatment of class II division 1 malocclusion in the permanent dentition. Study selection, data extraction, risk of bias assessment, and assessment of the strength of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool were performed in duplicate.

RESULTS

Out of the 27 articles that met the initial eligibility criteria, 19 studies were finally selected. Fair to relatively good quality evidence was identified after the risk of bias assessment of the included studies. Out of the 19 selected studies, 5 studies used inter-radicular TADs, 10 studies used modified C- palatal plate (MCPP), 3 studies used infra zygomatic crest (IZC) TADs, 1 study compared buccal TADs versus MCPP, and 1 study compared between cervical headgear and MCPP. The maximum amount of maxillary arch distalization using buccal TADs, MCPP, IZC TADs, and headgear was 4.2mm, 5.4mm, 5mm, and 2.5mm respectively. Different results regarding the amount of dental, skeletal, and soft tissue changes were observed.

CONCLUSIONS

The current low to very low certainty level of evidence suggests that TMAD is effective in camouflaging class II division 1 malocclusion. Future well-conducted and clearly reported randomized controlled trials that include a control group are needed to make robust recommendations regarding the effect of TMAD with different appliances on dental, skeletal, and soft tissue structures.

CLINICAL RELEVANCE

TMAD should be given priority with caution in class II patients who refuse the extraction of premolars. TMAD may be considered an adjunctive approach to solve cases associated with high anchorage need or anchorage loss.

Effect of local injection of injectable platelet-rich fibrin on bone remodeling during orthodontic tooth movement in dogs

Background

This study aimed to assess the effect of local injection of injectable platelet-rich fibrin (i-PRF) on bone remodeling during orthodontic tooth movement in dogs.

Materials and Methods

In this animal study, the maxillary first premolars of four adult male mixed-breed dogs were bilaterally extracted, and a nickel-titanium closed coil spring with 150 g force was placed between the canine and second premolar teeth. One quadrant of the maxilla was randomly selected as the test quadrant, and 0.5 cc i-PRF was injected into the periodontal ligament (PDL) around the second premolar at 1, 21, and 42 days. The other quadrant served as the control group and received saline injections. The dogs were sacrificed after 63 days, histological sections were prepared, and changes in bone remodeling were assessed by comparing the percentage of osteogenesis and number of osteoblasts and osteoclasts between the two groups by the Wilcoxon and Mann-Whitney U-tests (α = 0.05).

Results

The percentage of osteogenesis (16.0% ± 4.96% in i-PRF and 13.5% ± 4.43% in the control), the percentage of newly formed lamellar bone (10.25% ± 2.87% in i-PRF and 8.75% ± 2.36% in the control), the percentage of woven bone (5.75% ± 2.21% in i-PRF and 4.75% ± 2.36% in the control), the number of osteoblasts (15.0 ± 3.46 in i-PRF and 11.75 ± 2.36 in the control), and the number of osteoclasts (11.25 ± 4.34 in i-PRF and 6.25 ± 2.62 in the control) were not significantly different between the two groups (P > 0.05).

Conclusion

PDL injection of i-PRF around the second premolars of dogs under orthodontic force had no significant effect on bone remodeling.

Wilckodontics: A Multidisciplinary Approach for Orthodontic Treatment

Wilckodontics is the periodontally accelerated orthodontic treatment, which is a clinical procedure that combines orthodontic tooth movement with corticotomy and bone grafting. Corticotomy is the surgical procedure that involves cutting the bone, perforating the bone and mechanically altering it. This procedure makes tooth movement easy and rapid with the help of orthodontic force application. This procedure is based on the regional acceleratory phenomenon that increases the bone width, shortens the treatment time from years to months and increases the treatment stability. This procedure also reduces the need for extraction and also increases bone support for teeth and soft tissues. This review article describes the surgical procedure, advantages, disadvantages, indications, and contraindications of Wilckodontics and the current advances in this technique.

Quantitative assessment of root resorption in TAD-aided anchorage with and without RAP: A CBCT study on en masse retraction cases

INTRODUCTION

The purpose of this study was to evaluate the amount of root resorption with mini implant-aided anchorage, with and without inducing the regional acceleratory phenomenon (RAP) in en masse retraction cases using cone-beam computed tomography (CBCT).

METHODS

Thirty patients requiring therapeutic extraction of all first premolars were included in the study and randomly divided into two groups of fifteen patients each (groups I and II). Patients of both groups underwent retraction using mini implants. In patients of group II, the RAP was initiated before starting retraction. For each patient, CBCT of the maxillary and mandibular anterior region was taken before treatment and after retraction to evaluate root length changes.

RESULTS

The amount of root resorption post-retraction was lesser in group II as compared to group I for the maxillary canine, mandibular canines, and mandibular lateral incisors. When the amount of root resorption was scored according to the Malmgren index, a greater percentage of teeth in group I (17.8%) showed root resorption of score of 3 as compared to group II (6.1%).

CONCLUSION

The results of the study show that the RAP caused reduced root resorption, but its effect was localized to the area where it was induced. When mini implants are used for absolute anchorage during en masse retraction, the RAP can be induced to reduce the root resorption that results from increased treatment time associated with implant-aided retraction.

Use of Melatonin/Decorticotomy and Autogenous Bone Graft in Induced 1-Wall Defect

PURPOSE

This study was designed to investigate the effect of intramarrow penetration (IMP) and 1% melatonin (MLN) gel on the remodelling process of autogenous bone graft (ABG) in an induced 1-osseous wall defect model.

METHODS

Sixty-four intrabony induced mandibular defects were created on the distal side of premolars-P1, P2, P3, and P4 (on each side)-in 8 beagle dogs. A ligature-induced periodontitis was initiated in each defect. Defects were then divided into 4 equal groups. Group I was treated with open-flap debridement (OFD) alone, group II was treated with OFD/ABG, group III was treated with OFD/IMP/ABG, and group IV was treated with OFD/ABG/IMP/1% MLN gel. The study parameters were bone fill, histologic analysis, and immunohistochemical evaluation of endothelial nitric oxide synthase (eNOS) expression at 2-week (2W) and 8-week (8W) time intervals.

RESULTS

At 8W, significant differences were revealed amongst all groups regarding the amount of bone fill and eNOS expressions (P < .001). Bone fill percentages were 55.5%, 22.3%, 16.8%, and 0% in groups IV, III, II, and I, respectively. eNOS expressions were 1.68 ± 0.06, 8.43 ± 0.04, 16.80 ± 0.17, and 1.97 ± 0.07 in groups IV, III, II, and I, respectively. The favourable results were in line with group IV.

CONCLUSIONS

According to these preliminary results, defects treated by ABG augmented with IMP and 1% MLN gel revealed a greater amount of bone fill and reduced eNOS expression. This combination is therefore highly suggested as an adjunct to ABG.

A split-mouth randomized controlled trial to compare the rate of canine retraction after a soft tissue procedure compared against a corticotomy procedure for accelerated tooth movement

Background and Aim

Various methods to accelerate the orthodontic tooth movement have been used, among which corticotomy is considered to be the most common one. The suggested reasoning for such acceleration was the regional acceleratory phenomenon (RAP). Since the RAP is a property of both the hard and soft tissues, we designed a soft tissue flap procedure to compare the effects with the conventional corticotomy procedure. A split-mouth study was conducted where the two procedures were assessed in a single participant.

Patients and Methods

The total sample size was calculated to be 40 with 20 participants in each group. The rate of tooth movement was the primary outcome measure, and the secondary outcomes were dentoalveolar changes, which were studied in both the conventional corticotomy and the flap-only procedure based on a cone-beam computed tomography (CBCT) wherein the alveolar bone density (BD) around canines, tipping, and rotational changes in canines, premolars, and molars were assessed.

Results

Corticotomy resulted in greater canine angulation, lesser canine rotation and premolar rotation, and greater molar rotation compared with flap elevation, but these differences were statistically insignificant.

Conclusion

Though the corticotomy resulted in higher BD, the differences were statistically insignificant. There was no significant difference in the rate of space closure assessed by the two techniques compared.

One-stage versus two-stage piezocision-assisted orthodontic tooth movement: A preclinical study based on Nano-CT and RT-PCR analyses

OBJECTIVE

To evaluate the effect of a second-stage piezocision on the biological response.

MATERIALS AND METHODS

60 rats were randomly allocated to 6 experimental groups of 10 rats. Rats undergoing a one-stage piezocision were sacrified on day 7, 28 and 42 (groups 1-3) while rats undergoing a two-satge piezocision were sacrified on day 42, 63 and 90 (groups 4-6), respectively. The biological response was investigated in 3D at the tissue level using Nano-computed tomography (Nano-CT) and, at the molecular level using the qRT-PCR technique. Bone Volume Fraction (BVF) loss was the primary endpoint.

RESULTS

Similar loss of BVF were observed both after the first and second piezocisions. The change in BVF loss between 7 and 28 days after each piezocision were 25.1 ± 13.0 (SE)% and 11.2 ± 11.6 (SE)% respectively and did not differ from each other (p = 0.43). Changes in BVF loss from 7 to 42 days were also comparable in one-stage and two-stage piezocision (4.9 ± 12.3 (SE) vs. -19.9 ± 13.4 (SE), p = 0.19). At the molecular level, all parameters except Translating Ribosome Affinity Purification (TRAP) protein had identical patterns.

CONCLUSION

Within the limits of the present study, a second piezocision allowed to re-induce the Regional Acceleratory Phenomenon (RAP) effect. Nevertheless, the relevance of the findings to the clinical effect has not been tested.

Site-specific characteristics of bone and progenitor cells in control and ovariectomized rats

One-third of postmenopausal women experience at least one osteoporotic bone fracture in their lifetime that occurs spontaneously or from low-impact events. However, osteoporosis-associated jaw bone fractures are extremely rare. It was also observed that jaw bone marrow stem cells (BMSCs) have a higher capacity to form mineralized tissues than limb BMSCs. At present, the underlying causes and mechanisms of variations between jaw bone and limb bone during postmenopause are largely unknown. Thus, the objective of the current study was to examine the site-specific effects of estrogen deficiency using comprehensive analysis of bone quantity and quality, and its association with characterization of cellular components of bone. Nine rats (female, 6 months old) for each bilateral sham and ovariectomy (OVX) surgery were obtained and maintained for 2 months after surgery. A hemi-mandible and a femur from each rat were characterized for parameters of volume, mineral density, cortical and trabecular morphology, and static and dynamic mechanical analysis. Another set of 5 rats (female, 9 months old) was obtained for assays of BMSCs. Following cytometry to identify BMSCs, bioassays for proliferation, and osteogenic, adipogenic, chondrogenic differentiation, and cell mitochondrial stress tests were performed. In addition, mRNA expression of BMSCs was analyzed. OVX decreased bone quantity and quality (mineral content, morphology, and energy dissipation) of femur while those of mandible were not influenced. Cellular assays demonstrated that mandible BMSCs showed greater differentiation than femur BMSCs. Gene ontology pathway analysis indicated that the mandibular BMSCs showed most significant differential expression of genes in the regulatory pathways of osteoblast differentiation, SMAD signaling, cartilage development, and glucose transmembrane transporter activity. These findings suggested that active mandibular BMSCs maintain bone formation and mineralization by balancing the rapid bone resorption caused by estrogen deficiency. These characteristics likely help reduce the risk of osteoporotic fracture in postmenopausal jawbone.

Effect of Extending Corticotomy Depth to Trabecular Bone on Accelerating Orthodontic Tooth Movement in Rats

Corticotomy is a surgical procedure that induces injury to the cortical bone to accelerate tooth movement. This study aimed to increase the depth of corticotomy to the trabecular bone and to evaluate the amount and rate of tooth movement and alveolar bone changes in response to various degrees of cortical and trabecular bone injury. Seventy-eight male Wistar rats were randomly divided into four groups based on procedure used: (1) baseline control group of orthodontic tooth movement (OTM) only; (2) OTM + 4 corticotomies (CO); (3) OTM + 4 osteotomies (OS); and (4) OTM + 16 CO. A closed-coil nickel–titanium spring was placed to move the maxillary first molar mesially with a 10 g force. On days 0, 7, 14, and 21, alveolar bone alteration and tooth movement were measured using microcomputed tomography. Significant tooth movement was related to the number and the depth of the perforations. The OTM + 16 CO group showed a greater amount and rate of tooth movement than the OTM + 4 CO group. When osteotomy and corticotomy were compared with the same volume of bone removed, the OTM + 4 OS group had a faster rate of tooth movement than the OTM + 16 CO group during the first week, with significantly reduced bone volume. However, no significant difference was observed in the amount of tooth movement between the OTM + 4 OS and OTM + 16 CO groups at the end of the study. Extending the depth of corticotomy to trabecular bone increased the amount of tooth movement by accelerating the induction and completion of bone remodeling, which accelerated the rate of tooth movement during the initial stage.

Influence of dental implantation on bone mineral density distribution: a pilot study

PURPOSE

Masticatory loading triggers active bone remodeling, altering alveolar bone mineral density (BMD). While dental implants are placed to bear masticatory loading, their influence on changing bone properties has not been fully investigated. Objective of this pilot study was to examine whether the dental implantation has an effect on BMD distribution of bone by comparing dentate, edentulous, and edentulous patients with implants.

MATERIALS AND METHODS

Cone beam computed tomography (CBCT) images of 19 partially edentulous patients (Dent), 19 edentulous patients (Edent), and 16 edentulous patients who received implants in the mandible (Edent+Im), were obtained. CBCT images were also obtained from 5 patients within Edent+Im group, before implant placement and after implant loading. Basal cortical bone region of the mandible was digitally isolated. A histogram of gray levels proportional to BMD was obtained to assess mean, histogram standard deviation (HSD), fifth percentile of low and high values (Low₅ and High₅) of the BMD distribution. Multivariate analysis of variance and paired t-test were used to compare the BMD parameters among the 3 dental status groups and between pre- and post-implantation, respectively.

RESULTS

Edentulous patients with implants had significantly greater HSD and High₅ values compared to edentulous patients (P < .013). All other comparisons were not significant (P > .097). Mean, HSD, and High₅ values significantly increased after receiving implants (P < .022).

CONCLUSION

The current findings suggested that receiving dental implants promoted oral bone mineralization for edentulous patients. The longitudinal investigation could provide valuable information on understanding the effects of implantation on the behavior of oral bone quality.

The effect of micro-osteoperforations on orthodontic space closure investigated over 12 weeks: a split-mouth, randomized controlled clinical trial

OBJECTIVES

To evaluate the effects of minimally invasive micro-osteoperforations (MOPs) on orthodontic tooth movement and pain.

DESIGN

Prospective, split-mouth, randomized controlled trial.

SETTING

Single-centre, university hospital.

METHODS

Twenty subjects requiring maxillary first premolar extractions were included. Right and left sides of the maxilla were randomly allocated into experimental and controls. Space closure was initiated following alignment on 0.20″ stainless steel archwires, using 150 g force, applied by coil springs on power arms. Nance-TPA was used for anchorage. On the experimental side, two 5 mm deep MOPs in vertical alignment on distal aspect of the maxillary canine mid-root region were performed prior to space closure.

OUTCOMES

The primary outcome was the amount of tooth movement during space closure, measured every 4 weeks for 12 weeks (T1, T2, and T3). Secondary outcome was the pain levels related to MOP, measured using Visual Analogue Scale (VAS) questionnaires. Significance was set at P < 0.01.

RANDOMIZATION

Randomization was generated using a randomization table, and allocation was concealed in sequentially numbered, opaque, sealed envelopes.

BLINDING

Blinding was not possible during the experiment but assessor was blinded during outcome assessment.

RESULTS

All subjects completed the study, with tooth movement measurements available for all 20 patients for T0-T2. In three patients, space was closed on one side at T2. The average tooth movement between sides at three intervals (T0-T1, T1-T2, and T2-T3) were not significantly different. Overall difference following 12 weeks (T0-T3) was 0.69 mm higher on the experimental side (P < 0.001). No harms were observed.

LIMITATIONS

Short-term study, cast measurements done with digital callipers.

CONCLUSION

This 12-week randomized split-mouth controlled clinical trial showed two MOPs that are 5 mm deep, applied once prior to space closure, did not create clinically significant increase in maxillary premolar space closure.

PROTOCOL

The protocol was not published before trial commencement.

REGISTRATION

Trial was not registered.

FUNDING

The Australian Society of Orthodontists Foundation for Research and Education.

Long-Term Assessment of Periodontal Tissues after Corticotomy-Assisted Orthodontic Arch Expansion

OBJECTIVES

The aim of the study was the long-term assessment of the condition of periodontal tissues after corticotomy-assisted orthodontic expansion in patients with transverse maxillary deficiency.

MATERIALS AND METHODS

The study included a group of 18 adults (9 women, 9 men) aged between 24 and 40 years who were at least 5 years post treatment. The following parameters were assessed: the full mouth plaque index (FMPI), full mouth bleeding on probing (FMBOP), probing depth (PD), clinical attachment level (CAL), gingival recession height (GR), recession width (RW), papilla height (PH), papilla width (PW), bone sounding (BS), phenotype, and KT.

RESULTS

During examination performed at least 5 years after the completion of orthodontic treatment, the values of PD and CAL were found to be considerably decreased compared to the examination one year post treatment (PD: -0.23; 95% Cl: -0.29, -0.16) (CAL: -0.04; 95% Cl: -0.17, 0.10). The other parameters-FMPI, FMBOP, GR, RW, PH, PW, BS, phenotype, and KT-did not change significantly.

CONCLUSIONS

Corticotomy-assisted orthodontic arch expansion does not have a negative effect on the periodontium in long-term observations.

CLINICAL RELEVANCE

Orthodontic arch expansion can lead to bone dehiscence and gingival recession. Long-term observations revealed that corticotomy-assisted orthodontic expansion of the upper arch is not followed by negative changes in periodontal status.

Patient First: Surgery First and More

INTRODUCTION

The success of surgery first approach has been defined by the number of advantages offered and is definitively determined by the satisfaction of the patients themselves. The strength of this protocol resides in its philosophy that puts the patient at the center of the whole diagnostic-therapeutic process. The compliance of the patient, its happiness and comfort are the best guarantee of a good final results. While pursuing this philosophy we have wondered whether there was way to increase the comfort of surgery first approach even more and to make it even more appealing for the patients. For these reasons, we have decided to work on a preliminary protocol in order to reduce or even eliminate the use of orthodontic braces and wires during perioperative stages. Materials and Methods: No orthodontic braces or wires are bonded on the teeth before surgery. Intraoperatory intermaxillary fixation (IMF) is carried out with the use of IMF screws which are positioned at the beginning of the operation on the edge between keratinized and nonkeratinized gingiva. Once the osteotomies are performed IMF with IMF screws is carried out on the planned occlusion with the use of surgical splints.Discussion and Conclusions: In selected cases the postsurgical orthodontic treatment can be carried out with the use of clear aligners, completely eliminating the need of braces and wires with an additional level of comfort.

The application of orthodontic bone stretching for correcting malpositioned dental implants

Background

Dental implants are sometimes initially placed in a wrong position leading to esthetic damage, which is difficult to solve with prosthetics. Moreover, implants placed in the anterior sector, like ankylosed teeth, are frequently found in a wrong position over time with infraocclusion because of continuous anterior alveolar growth. Different treatments have been proposed to manage the consequences of malpositioned dental implants.

Case presentation

This paper describes a surgical and orthodontic new procedure that can be used to relocate an implant in a wrong position: the Orthodontic Bone Stretching technique (OBS), which involves deep partial osteotomies combined with heavy orthodontic forces. The applied force facilitates esthetic rehabilitation with a movement towards the occlusal plane and can modify the implant axis and the gingival line alignment. This relocation is made possible thanks to a bone stretching phenomenon in the surgical area without immediate mobilization or repositioning of an alveolar segment. Three cases with the need for implant repositioning are presented here and were treated with the OBS technique.

Conclusion

In the three cases presented, implant relocation was successfully performed with the OBS technique and the prosthetic crown was modified to improve esthetic results.

Assessment of the effects of local platelet-rich fibrin injection and piezocision on orthodontic tooth movement during canine distalization

INTRODUCTION

The study aimed to evaluate and compare the effects of local platelet-rich fibrin (PRF) injection and piezocision applications on tooth movement during canine distalization, as well as to evaluate any changes in the periodontal parameters.

METHODS

Twenty-four patients were randomly divided into 2 groups. A randomly selected side of the maxillary arch received either PRF injection (PRF group) or piezocision (piezocision group). The contralateral sides of both groups served as the controls. After piezocision and PRF injection applications, canine distalization was initiated in both groups with a 150 g force. Patients were followed every 2 weeks for a total 12 of weeks. The following variables were evaluated: cephalometric measurements, the amount of canine distalization, molar mesialization, canine rotation, transversal changes in dental models, and periodontal parameters.

RESULTS

The amount of canine distal movement was found to be greater in the experimental sides than in the control sides in both groups at 12 weeks (P <0.05). There were no differences in the amount of molar mesialization, canine rotation, or transversal measurements in both groups when compared with the experimental sides with the control sides (P >0.05). There were no differences in the skeletal measurements or periodontal parameters in both groups (P >0.05). In both groups, the maxillary incisors were retroclined and retracted.

CONCLUSIONS

PRF and piezocision accelerated tooth movement, but there were no differences between the 2 applications in terms of speed, amount, duration of tooth movement, or periodontal parameters during canine distalization.

Disentangling the effects of CAD/CAM customized appliances and piezocision in orthodontic treatment: New evidence

OBJECTIVES

To discern the effects of computer-aided design (CAD)/computer-aided manufactured (CAM) customized appliances and piezocision on orthodontic treatment (OT).

MATERIALS AND METHODS

The study combined findings from two previously published randomized controlled trials: (1) standard OT vs piezocision-assisted standard OT, and (2) CAD/CAM OT vs piezocision-assisted CAD/CAM OT. Piezocision is a minimally invasive corticotomy surgical procedure used to accelerate orthodontic treatment and CAD/CAM refers to CAD/CAM customized brackets and archwires. The outcomes were the overall treatment time, and the durations of the alignment phase and fine-tuning phase. Clinical and radiological features also were evaluated.

RESULTS

The combined study included 48 patients with similar baseline characteristics. Compared to the standard treatment, CAD/CAM technology alone significantly decreased the overall median OT time from 543 to 394 days (P < .001) and from 543 to 254 days (P < .0001) when combined with piezocision. Although piezocision significantly reduced the duration of the alignment phase in the mandible and maxilla, CAD/CAM technology considerably shortened the fine-tuning phase. All periodontal and radiographic parameters remained stable from the start to the end of treatment in all groups.

CONCLUSIONS

CAD/CAM technology combined with piezocision accelerates the entire OT process, during the alignment phase for piezocision and during the fine-tuning phase for CAD/CAM, with a global reduction of the overall treatment time of more than 50%.

Periodontally accelerated osteogenic orthodontics with platelet-rich fibrin in an adult patient with periodontal disease: A case report and review of literature

BACKGROUND

In the clinical scenario, adult patients with periodontal diseases and dental malformation, characterized by dental crowding in lower anterior teeth with the thin biotype, often require orthodontic treatment. This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics (PAOO) combined with autologous platelet-rich fibrin (PRF) in an adult patient with class I malocclusion along with dental crowding, a thin periodontal biotype, and buccal plate deficiency.

CASE SUMMARY

A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic. The patient underwent periodontal risk assessment prior to orthodontic treatment. She was diagnosed with a high risk of gingival recession due to dental crowding, root prominence, loss of buccal plates, and a thin gingival tissue biotype. The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding. Clinically, PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling. Radiographic outcomes also showed statistically significant improvements (P < 0.01) in the mandibular buccal alveolar bone.

CONCLUSION

This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.

Biomechanical Interfaces of Corticotomies on Periodontal Tissue Remodeling during Orthodontic Tooth Movement

Corticotomy is an effective approach in accelerating orthodontic tooth movement (OTM) in clinical treatment. Corticotomy causes regional acceleratory phenomenon (RAP) in the alveolar bone of surgical sites. However, the molecular mechanism of RAP after corticotomy remains unclear. Herein, we established a mouse model to study the biomechanical interfaces of corticotomy-assisted OTM and to investigate the histological responses and underlying cellular mechanism. A total of 144 male C57BL/6 mice were randomly assigned into four groups: corticotomy alone (Corti), sham operation (Sham), corticotomy with tooth movement (Corti + TM), and sham operation with tooth movement (Sham + TM). Nickel–titanium orthodontic springs were applied to trigger tooth movement. Mice were sacrificed on Post-Surgery Day (PSD) 3, 7, 14, 21, and 28 for radiographic, histological, immunohistochemical, and molecular biological analyses. The results reveal that corticotomy significantly promoted alveolar bone turnover and periodontal tissue remodeling. During orthodontic tooth movement, corticotomy significantly promoted osteogenic and proliferative activity, accelerated tooth movement, and eliminated root resorption by upregulating Wnt signal pathway.

Effect of piezocision on molar intrusion in open-bite treatment using a modified MEAW technique

PURPOSE

The aim of this retrospective study was to investigate whether a piezocision technique influences molar intrusion in open-bite cases.

METHODS

In all, 30 patients with open-bite malocclusion were assigned to one of two groups: the piezocision group comprised 15 patients who were treated using curved arches and anterior elastics with the simultaneous combination of piezocision which was performed interdentally in the upper posterior region, while the control group comprised 15 patients who were treated with the same treatment mechanics without piezocision. In both groups, after leveling and aligning, upper 0.017 × 0.025 accentuated curve and lower 0.017 × 0.025 reversed curve of Spee NiTi archwires were placed. Anterior vertical elastics were applied between laterals and the canines on both sides. The effects of treatments were investigated on cone-beam computed tomography images acquired before use of elastics and after correction of open-bite.

RESULTS

Open-bite closure was achieved in 2.85 ± 0.85 and 4.1 ± 1.58 months in the piezocision and control groups, respectively, while total treatment lasted 1.4 ± 0.42 and 1.7 ± 0.43 years, respectively. Extrusion of lower posterior teeth (p < 0.05) was observed together with extrusion of incisors and canines (p < 0.001) in the piezocision group, while only incisors and canines were extruded in the control group (p < 0.001). There were no significant differences between the groups (p > 0.05) except significant lower incisor extrusion (p < 0.05) and counter-clockwise rotation of the lower occlusal plane in the piezocision group (p < 0.001).

CONCLUSION

The duration of open-bite correction was significantly shorter in the piezocision group. No molar intrusion was observed in either group. Open bite correction was achieved mainly by extrusion and retrusion of the incisors while maintaining upper molar positions.

Comparison of Rate of Canine Retraction and Secondary Outcomes Associated With Conventional Fixed Orthodontic Treatment and Minimally Invasive Techniques (MOPs): A Randomized Control Trial

Introduction:

The objective of the study was to assess the rate of canine retraction and secondary outcomes associated with conventional fixed orthodontic treatment (CFO) and CFO with micro-osteoperforation (CFO + MOP), that is, anchorage loss, root resorption, vitality of tooth, pain and discomfort level during the procedure.

Methods:

A total of 16 patients with Class II Division 1 malocclusion who required upper first premolar extraction with lower non-extraction/single incisor extraction were divided into the test group (MOP) and positive control group (CFO + MOP) for a split-mouth study. Both maxillary canines were retracted with nickel–titanium (NiTi) closed coil springs. Patients were reviewed after 24 hours, 7 days, 28 days, and 4, 8, and 16 weeks to assess the rate of tooth movement, anchorage loss, root resorption, vitality of tooth, pain and discomfort level.

Results:

There was a statistically significant difference in the rate of tooth movement between the CFO and CFO + MOP groups after the first 4 weeks ( P-value = .026), whereas no statistically significant difference was observed at 8, 12, and 16 weeks ( P-value = .33, .99, and .08, respectively). In the CFO group, there was no statistically significant difference in tooth movement between different time intervals ( P-value > .05). There was no significant difference in root resorption between the groups. The pain level was higher in the MOP group in the first 24 hours ( P-value < .05) after the procedure. Later on, the difference in pain level between the groups was not significant ( P-value > .05). The vitality of retracted canines in both groups was healthy.

Conclusion:

The study recommends that the CFO + MOP procedure has substantial potential to be used as an adjunct to the routine mechanotherapy for faster tooth movement, as it may reduce the treatment time by half in the first 4 weeks after the MOP procedure. There are no potential differences in anchorage loss, tipping, vitality, and apical and lateral root resorption between the CFO and CFO + MOP groups. This trial was registered at Clinical Trial Registry, India.

Clinical follow-up of corticotomy-accelerated Invisalign orthodontic treatment with Dental Monitoring

The demand for fast and invisible treatment options for adults has grown. Treatment protocols involving clear aligners in association with alveolar corticotomy have been developed in response to this demand. Alveolar corticotomy surgery can accelerate orthodontic tooth movement, but good clinical follow-up is crucial and can become cumbersome as the frequency of aligner changes accelerates. Clinical monitoring with patient-managed software can be of assistance in such cases. We present the ortho-surgical treatment of a healthy 21-year-old woman with Class III malocclusion who was treated with corticotomy-accelerated presurgical decompensation and clear aligners, followed by mandibular sagittal split osteotomy. Alveolar corticotomy surgery was performed and the aligners were changed every 4 days. Clinical follow-up of aligner-mediated tooth movement was managed with a patient-managed smartphone application, allowing early interception and correction of minute orthodontic movement errors. Such errors would have been difficult to detect considering the rapidity of aligner change when accelerated by alveolar corticotomy. Clinical follow-up with a patient-managed smartphone application could thus allow for better and easier management of corticotomy-accelerated clear aligner orthodontic treatment.

Buccal bone regeneration combined with piezocision in adult orthodontic patients: Clinical, 3D radiographic, and patient-reported outcomes

OBJECTIVE

Assess the clinical effects, 3D radiographic results and patient-reported outcome measures (PROMs) of buccal bone regeneration combined with piezocision.

METHODS

Ten patients presenting roots prominence with a thin buccal bone thickness or buccal bone dehiscence in the lower front region were enrolled. Patients received orthodontic treatment assisted by piezocison which was combined with a buccal alveolar bone regeneration using a tunneling approach. A comparison between pre- and post-treatment alveolar bone measurements based on CBCT was performed. Periodontal parameters such as recession scores and root resorption were recorded before and after treatment. The PROMs were also investigated.

RESULTS

An overall significant buccal bone gain of 2.7 ± 2.7% was found after the treatment. The apical region reached the highest gain of 8.9 ± 5.5% whereas the most coronal region showed no significant increase of the bone envelope (1.2 ± 2.7%). No adverse event such as the appearance of recession or root resorption were observed. However, in 2 patients, the biomaterial was not properly integrated and seemed to be encapsulated. The pain level and the paracetamol consumption were equivalent to those after the placement of the orthodontic appliance except on the day of the surgery.

CONCLUSIONS

Within the limitation of this study, piezocision combined with buccal bone regeneration using a tunneling technique seems to be effective to augment bone and did not lead to gingival recession. However, in 2 cases the biomaterial seemed encapsulated, and therefore the predictability of the integration of the material can be questioned. ClinicalTrials.gov registration : NCT03655938.

Which method is more effective for accelerating canine distalization short term, low-level laser therapy or piezocision? A split-mouth study

OBJECTIVES

This study evaluated and compared the effects of low-level laser therapy (LLLT) and piezocision on the amount of orthodontic tooth movement.

MATERIALS AND METHODS

Forty maxillary canines from 20 patients (mean age, 16.35 ± 1.14 years) were evaluated in a split-mouth design study. Miniscrew-supported canine distalization was performed. Piezocision was applied in the right maxillary canine region, and the left maxillary canines were irradiated with a diode laser (940 nm, 5 J/cm²). LLLT was performed on day 0 and days 3, 7, 14, 21, and 28 after the start of canine distalization in the first 4‑week period. Data were evaluated at baseline (T0) and after 4 (T1), 8 (T2), and 12 (T3) weeks. The amount of canine movement was determined from three-dimensional models, and the angulation of canines and first molars was analyzed based on lateral cephalograms.

RESULTS

Intragroup and intergroup comparisons of canine distalization were performed for four different time intervals (T0-T1, T1-T2, T2-T3, T0-T3). The canine tooth movement in the T0-T1 period was significantly greater in the LLLT group compared to the piezocision group. No statistically significant differences were observed between the groups for the T1-T2, T2-T3, and T0-T3 periods. The amount of canine distalization in the T0-T1 period was significantly greater than that in the T1-T2 and T2-T3 periods in both groups. Tooth movement during the T1-T2 period was higher than that in the T2-T3 period in the LLLT group. Cephalometric evaluation revealed no statistically significant difference between the groups with respect to canine and first molar angulation.

CONCLUSION

Although laser application seems more effective during the first 4‑week period, considering the 12-week period, the effects of LLLT and piezocision on orthodontic tooth movement during canine distalization were similar.

Osseous evidence behind micro-osteoperforation technique in accelerating orthodontic tooth movement: A 3-month study

INTRODUCTION

The study aimed to investigate the effects of micro-osteoperforations (MOPs) on the mandibular bone volume/tissue volume (BV/TV) ratio changes and the rate of orthodontic tooth movement using cone-beam computed tomography images. Another objective was to evaluate the effects of MOP frequency intervals (4 weeks, 8 weeks, and 12 weeks) on the BV/TV ratio and rate of tooth movement.

METHODS

In 24 participants, 140-200 g of force was applied for mandibular canine retraction. Three MOPs were made according to the scheduled intervals of the 3 different groups: group 1 (MOP 4 weeks), group 2 (MOP 8 weeks), and group 3 (MOP 12 weeks) directly at the mandibular buccal cortical bone of extracted first premolars sites. Cone-beam computed tomography scans were obtained at the 12th week after MOP application. Computed tomography Analyzer software (version 1.11.0.0; Skyscan, Kontich, Belgium) was used to compute the trabecular alveolar BV/TV ratio.

RESULTS

A significant difference was observed in the rate of canine movement between control and MOP. Paired t test analysis showed a significant difference (P = 0.001) in the mean BV/TV ratio between control and MOP sides in all the frequency intervals groups. However, the difference was significant only in group 1 (P = 0.014). A strong negative correlation (r = -0.86) was observed between the rate of canine tooth movement and the BV/TV ratio at the MOP side for group 1 and all frequency intervals together (r = -0.42).

CONCLUSIONS

The rate of orthodontic tooth movement can be accelerated by the MOP technique with frequently repeated MOPs throughout the treatment.

Overcoming compact bone resistance to tooth movement

The general boundaries to tooth movement are within the adjacent compact and trabecular bones, gingiva, mucosa, and muscular envelope. Findings from finite element analysis of maxillary posterior teeth distalization against mini-implants suggest that stiff outer and interproximal compact bone resists tooth movement, regardless of bone thickness, and that teeth should be steered away from this bone during orthodontic treatment. However, individual variation in the tooth-bone interface dictates the course and outcome of treatment, offering the basis for inferences on the limits of mini-implant anchorage and the presumed influence of the regional acceleratory phenomenon through decortication and microperforation, 2 modalities advocated to effect faster tooth movement.

Effect of two corticotomy protocols on periodontal tissue and orthodontic movement

Objective

To compare two corticotomy surgical protocols in rats to verify whether they alter conventional orthodontic movement.

Methodology

Sixty Wistar rats were divided into three groups – orthodontic movement (CG), orthodontic movement and corticotomy (G1) and orthodontic movement with corticotomy and decortication (G2) – and euthanized after 7 and 14 days. Tooth movement (mm), bone volume fraction and bone volume ratio to total volume (BV/TV), and bone mineral density (BMD) were evaluated by micro-CT. The total amount of bone was measured in square millimeters and expressed as the percentage of bone area in the histomorphometry. The number of positive TRAP cells and RANK/RANKL/OPG interaction were also investigated.

Results

Day 14 showed a statistically significant difference in orthodontic tooth movement in CG compared with G1 (7.52 mm; p=0.009) and G2 (7.36 mm; p=0.016). A micro-CT analysis revealed a difference between CG, G1 and G2 regarding BV/TV, with G1 and G2 presenting a lower BV/TV ratio at 14 days (0.77 and 0.73 respectively); we found no statistically significant differences regarding BMD. There was a difference in the total amount of bone in the CG group between 7 and 14 days. At 14 days, CG presented a significantly higher bone percentage than G1 and G2. Regarding TRAP, G2 had more positive cells at 7 and 14 days compared with CG and G1.

Conclusion

Corticotomy accelerates orthodontic movement. Decortication does not improve corticotomy efficiency.

Regional variations of jaw bone characteristics in an ovariectomized rat model

Postmenopausal osteoporosis causes severe loss of bone quantity and quality in limb bone but has a lesser effect on jaw bone. Thus, the objective of this study was to examine whether ovariectomy (OVX) and mastication alter the regional variation of jaw bone characteristics. Sprague-Dawley female rats (6 months) were given a bilateral OVX or a sham operation (SHAM) (n = 10 for each group). After 2 months post-OVX, the hemi-mandible from each rat was dissected. A micro-computed tomography based mean, standard deviation (SD), the lower and upper 5th percentile (Low₅ and High₅) values of tissue mineral density (TMD) histograms were assessed for whole bone (WB), alveolar bone (AB), cortical bone (CB), and trabecular bone (TB) regions. Morphology of TB and periodontal ligament (PDL) was also obtained. Layers of AB were segmented up to 400 μm from the PDL. Mechanical properties at the tissue level were measured by nanoindentation at the same site by a single loading-unloading cycle of indentation in hydration. The AB and TB regions had significantly lower TMD Mean, Low₅, and High₅ but higher SD than the CB region for both sham and OVX groups (p < 0.01). TMD parameters of the OVX group rapidly increased up to 60 μm away from the PDL and were significantly higher than those of the sham group starting at 280 μm and farther in the CB region (p < 0.05). All values of morphological and nanoindentation parameters were not significantly different between sham and OVX groups (p > 0.06). Estrogen deficiency induced by OVX did not deteriorate bone characteristics including mineral density, morphology, and nanoindentation parameters in rat mandibles. Masticatory loading had an effect on the TMD parameters at the limited region of AB. These results provide insight into why osteoporosis-associated jaw bone fractures are extremely rare.

Assessment of bone density changes following two-jaw surgery using multidetector computed tomography: A pilot study

Objective

The aim of this retrospective study was to evaluate the pre- and postsurgical bone densities at alveolar and extra-alveolar sites following two-jaw orthognathic surgery.

Methods

The sample consisted of 10 patients (mean age, 23.2 years; range, 18.0–27.8 years; 8 males, 2 females) who underwent two-jaw orthognathic surgery. A three-dimensional imaging program (Invivo 5) was used with multidetector computed tomography images taken pre- and postoperatively (obtained 32.3 ± 6.0 days before surgery and 5.8 ± 2.6 days after surgery, respectively) for the measurement of bone densities at the following sites: (1) alveolar bone in the maxilla and mandible, (2) extra-alveolar sites, such as the top of the head, menton (Me), condyle, and the fourth cervical vertebrae (C4).

Results

When pre- and postsurgical bone densities were compared, an overall tendency of decrease in bone density was noted. Statistically significant reductions were observed in the densities of cancellous bone at several areas of the maxillary alveolar bone; cortical and cancellous bone in most areas of the mandibular alveolar bone; cortical bone in Me; and cancellous bone in C4. There was no statistically significant difference in bone density in relation to the depth of the alveolar bone. In a comparison of the bone densities between groups with and without genioplasty, there was almost no statistically significant difference.

Conclusions

Accelerated tooth movement following orthognathic surgery may be confirmed with reduced bone density. In addition, this study could offer insights into bone metabolism changes following orthognathic surgery, providing direction for further investigations in this field.

Modified Orthodontic Bone Stretching for Ankylosed Tooth Repositioning: A Case Report

Background:

Different approaches were proposed in the literature for the treatment of malpositioned ankylosed teeth. The present case report describes a modification of Orthodontic Bone Stretching Technique (OBS) for the repositioning of ankylosed teeth, consisting of dentoalveolar segmental osteotomies performed with piezoelectric instruments followed by orthodontic and orthopedic traction.

Case Report:

A 22-year-old female in good general health was referred by her orthodontist due to an infraoccluded and ankylosed maxillary upper left canine. Attempts of conventional and corticotomy-assisted orthodontic alignment of the tooth were previously performed with no success. After elevating a full-thickness flap, three osteotomies were performed by using piezoelectric inserts (Piezotome Cube, Acteon, Merignac, France). Mesial and distal cuts were full-thickness osteotomies, parallel to the long axis of the tooth, through the buccal and palatal cortical plates. The apical osseous incision was a horizontal corticotomy, involving only the buccal plate, and connecting the vertical osteotomies two millimetres over the apex of the tooth. Heavy orthodontic forces were immediately applied by using both dental and skeletal anchorage. The initial movement of the dentoalveolar segment was observed three weeks after surgery and case finishing has been completed in two months. At a one-year follow-up, the repositioned canine showed good periodontal conditions, no discoloration and positive pulp response to the electric test.

Conclusion:

Modified OBS technique was effective in repositioning an infraoccluded and ankylosed maxillary canine, providing satisfactory function and esthetics with short treatment time.

Vestibular Incision Subperiosteal Tunnel Access (VISTA) for Surgically Facilitated Orthodontic Therapy (SFOT)

Surgically Facilitated Orthodontic Therapy (SFOT) in combination with bone augmentation and the placement of anchorage devices installed into bone have been used to accelerate and facilitate orthodontic treatment. This is usually performed after flap surgery, which is associated with moderate morbidity, as well as possible negative sequale such as gingival recession. The present case report illustrates the clinical benefits of vestibular incision subperiosteal tunnel access (VISTA) for SFOT, and tissue augmentation to facilitate orthodontic therapy. VISTA entails making vertical incision(s) in the vestibule followed by subperiosteal elevation of tunnels to provide direct access to the facial alveolar bone. Unlike previously reported vestibular access surgical procedures, VISTA allows for wider elevation of an access tunnel for clear visual and surgical access to perform careful inter-radicular corticotomy. The present report describes VISTA for corticotomy surgery (anterior mandible and maxillary teeth) in combination with the placement of titanium fixation devices and bone augmentation to facilitate orthodontic treatment of an adult female with borderline Class II Division 1 malocclusion, with excessive overjet and deepbite. In view of the fact that VISTA does not require surface incisions in the gingival margins or papillae, it potentially minimizes gingival recession that sometimes accompanies flap surgery.

Segmental Corticotomy-Assisted Orthodontic Treatment With Platelet-Rich Fibrin Augmentation of Class III Anomaly

This clinical report presents the outcomes of segmental corticotomy-assisted orthodontic treatment in a class III patient. A 13.5-year-old female patient presented with class III anomaly and a thin alveolus in the mandibular anterior region. After the alignment of the mandibular incisors, segmental corticotomy with platelet-rich fibrin (PRF) was performed in the mandibular incisor area to facilitate incisor retraction to ensure periodontal support after the changes in the inclination of the teeth. Lateral cephalograms were taken at the beginning (T0), precorticotomy (T1), at the end of the treatment (T2), and 2 years after the treatment (T3). Cone-beam computed tomography (CBCT) records were collected at the T1, T2, and T3 periods to evaluate the bone structures. The measurements included the inclination and the position of the mandibular incisors, symphysis width, symphysis height, B-B' width, cervical alveolar width, the vertical alveolar bone level on the labial and the lingual sides, and the amount of labial and lingual bone at the apex in the mandibular central incisor and canine areas.The class I molar and canine relationship was achieved in this borderline case. The amount of labial bone at the root apex and the B-B' width increased. A vertical alveolar bone gain was observed. The facial profile was improved significantly. The treatment outcome was stable at the 2-year follow-up. The segmental anterior mandibular corticotomy provided an effective correcting inclination of the mandibular teeth with the use of class III elastics. This technique ensured the maintenance of a sufficient amount of labial bone with no periodontal side effects.

Comparative Evaluation of Effects of Different Corticotomy Designs on Velocity of Upper Canine Retraction: A Finite Element Study

Purpose: Understanding the effects of different corticotomy designs on the velocity of maxillary canine retraction.

Materials and Method: The 3-dimensional model of maxillary dentition was constructed and 3 corticotomy designs were compared with the conventional approach of canine retraction. 4 models were constructed for the present study: 1 with no corticotomy cuts (model 1), 1 with vertical cuts on both buccal and palatal side (model 2), other with cuts only on buccal side (model 3), and 1 with circular holes (model 4). Stress intensity and force distribution were evaluated after applying 150 gm of orthodontic forces on maxillary canine.

Results: Models with corticotomy approaches exhibited approximately twice the displacement when compared with conventional noncorticotomy procedure. The stresses were mainly concentrated on the distal side of the canine in all the models. The rate of canine retraction was the highest in model with buccal and palatal corticotomy compared to other designs.

Conclusions: Corticotomies help orthodontists to alter the biomechanical responses of dentoalveolar structures during maxillary canine retraction and accelerate tooth movement. Clinically, buccal corticotomy is a better choice for the patients as it is less traumatic and more acceptable to patients.

Comparison of the efficiency of alveolar decortication and low level laser therapy on orthodontic tooth movement and alveolar metabolism in rats

Background/purpose

Reducing orthodontic treatment duration has many advantages for both clinicians and patients. This study was designed to compare the effects of alveolar decortication and low level laser therapy methods on tooth movement rate and alveolar bone metabolism.

Materials and methods

A total of 42 Wistar albino rats were divided into three main groups as: Alveolar decortication (AD), low level laser therapy (LLLT) and only orthodontic force (F). The groups were evaluated at 7 and 14 day time points. Tooth movement rates were calculated by measuring the space between the contact points of the first and second molars. Comparisons regarding the alveolar bone metabolism were accomplished by evaluating osteoclast counts and RANKL - OPG expressions.

Results

The rate of tooth movement, at all time points, was significantly higher for the AD group than the other groups and was significantly higher in the LLLT group than the F group. At both time points, the RANKL and OPG expression in the AD group was significantly higher than the other groups and these parameters in the LLLT group was significantly higher than the F group. The osteoclast count values in the AD and LLLT groups were significantly higher than the F group and there were no significant differences between these two groups at all time points.

Conclusion

This study shows that, to be more effective at AD, both AD and LLLT therapy significantly increases the level of tooth movement in the early period through their stimulating effects on the alveolar bone metabolism.

Evaluation of enzyme activity and rate of tooth movement in corticotomy-accelerated tooth movement - A randomized clinical trial

BACKGROUND:

This study was undertaken to evaluate the enzyme activity profiles in human saliva and gingival crevicular fluid (GCF) in accelerated tooth movement when compared with normal orthodontic tooth movement (OTM) in extraction cases.

MATERIALS AND METHODS:

Twenty patients who required premolar extractions were treated with MBT mechanotherapy. They were divided into two equal groups: conventional (Group I) and corticotomy (Group II) which was performed on both the jaw sides before initiating retraction. GCF was collected from mesial and distal aspects of canine before initiation of retraction and at 7^th, 14^th, 21^st, and 28^th days, and then at fifth and sixth weeks and third and sixth months after retraction. A total of 5 mL of unstimulated saliva was collected from the subjects after 90 min of nonoral activity (subjects were refrained from eating and drinking).

RESULTS:

The results showed that in Group I, the peak of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) enzyme activity occurred on the 14^th day of force application. In Group II, the enzyme activity progressively increased from day 0 to 6 weeks, peaking at the sixth week, and then a decline in enzyme activity was observed on third and sixth months. When ALP and AST activities in GCF and saliva were compared between Groups I and II, no statistically significant difference was observed on days 0, 7, and 14.

CONCLUSION:

Corticotomy-accelerated tooth movement is a promising technique that has many applications in orthodontic treatment of adults as it helps overcome many of the current limitations of this treatment. The enzymatic activity signifies osteoclastic and osteoblastic activities, so ALP and AST from the saliva and GCF may potentially be used as biomarkers for monitoring corticotomy-assisted OTM.

Alveolar restoration following rapid maxillary expansion with and without corticotomy: A microcomputed tomography study in sheep

Objective

This study examined bone microstructure restoration after rapid maxillary expansion (RME) with and without corticotomy over multiple retention periods.

Methods

Eighteen male Dorper sheep were randomly distributed into three groups (n = 6 each group): group 1, RME with corticotomy on the buccal and palatal sides; group 2, conventional RME treatment; and group 3, no treatment. Post-RME, trabecular bone microstructure and new bone formation were evaluated by using microcomputed tomography (microCT) and histomorphometry after a 4- or 12-week retention period. Intergroup differences in bone quality and bone remodeling were analyzed by using two-way analysis of variance with Bonferroni post-hoc test.

Results

The bone volume fraction (bone volume [BV]/total volume [TV]) values relative to the control in groups 1 and 2 were 54.40% to 69.88% after the 4-week retention period and returned to approximately 80% after the 12-week retention period. The pooled BV/TV values of the banded teeth in groups 1 and 2 were significantly lower than those of the control after the 4-week retention period (p < 0.05). However, after the 12-week retention period, the pooled BV/TV values in group 2 were significantly lower than those in groups 1 and 3 (p < 0.05). Histomorphological analysis showed that the new bone formation area in group 1 was approximately two to three times of those in group 2 and control.

Conclusions

Corticotomy significantly enhanced the restoration of bone quality after the retention periods for banded teeth. This benefit might result from the increased new bone formation after corticotomy.

Alveolar corticotomies for accelerated orthodontics: A new mini-invasive technique

Orthodontic and surgical techniques are constantly evolving and practitioners are facing an increasing demand for shorter treatments, with an expectation of results equivalent to conventional treatments. Corticotomies have made it possible to partly meet this need by facilitating dental movement in adult orthodontic care. Many surgical corticotomy techniques were proposed in the past presenting advantages but also a certain number of disadvantages. After retracing the various surgical techniques proposed and explaining the biological principles, we will introduce a new minimally invasive technique, without mucoperiosteal flap and without piezosurgery. This technique can be performed in the dental chair under local anaesthesia or sedation. It is simple and reproducible. This type of treatment combines comfort, speed and periodontal protection. Our objective is to provide more patients and practitioners with corticotomies while controlling the benefit/risk ratio.

Biological events related to corticotomy-facilitated orthodontics

Corticotomy-facilitated orthodontics is a clinical treatment modality comprising the application of conventional orthodontic forces combined with selective decortication of the alveolar process of the bone, which generates a localized process of bone remodeling (turnover) that enables accelerated orthodontic tooth movement. Compared with conventional orthodontic treatment, corticotomy-facilitated orthodontics is associated with reduced treatment time and reduces the frequency of apical external root resorption; however, this modality increases morbidity and financial costs. Although the clinical outcomes of corticotomy-facilitated orthodontics appear favorable, no results of evidence-based investigations of long-term outcomes are available in the literature, and the long-term effects of corticotomy-facilitated orthodontics on the teeth and periodontium are unclear. This narrative review discusses the biological events associated with corticotomy-facilitated orthodontics. Authoritative articles found in relevant databases were critically analyzed and the findings were integrated and incorporated in the text.

Study of bone remodeling in corticotomy-assisted orthodontic tooth movement in rats

The goal of this study was to determine the structure change of the alveolar bone and the expression of a group of bone remodeling-related factors. Sixty healthy male Wistar rats were randomly divided into three groups. Selective alveolar decortication (SAD), tooth movement (TM), and "combined therapy" (SAD+TM) was performed in group I, II, and III, respectively. On days 0, 7, 14, 21, and 42, a Micro-CT scan was performed on the maxillary alveolar bone and tooth. In addition, on days 0, 7, 14, 21, 28, and 42, some of the rats were killed by cervical dislocation and tissues were harvested. Analysis of scan data revealed a significant decrease in bone density of the alveolar bone at 14 days post-surgery, and increased at 42 days post-surgery to a level higher than that before the surgery. Microarray and bioinformatics analysis were performed to explore gene expression profile in three groups (SAD, TM, and SAD+TM), and a large number of differentially expressed genes were identified. In addition, real-time polymerase chain reaction was performed to determine the expression of bone remodeling-related factors. The expression of osteoblast-related cytokines, including osteopontin, bone sialoprotein, and osteocalcin, and osteoclast regulators macrophage-colony stimulating factor (M-CSF) and RANKL (activator of nuclear factor KB receptor ligand) were increased in group III, suggesting that there was increased bone synthesis and activation of bone absorption. Moreover, group III had a unique alveolar bone remodeling pattern: RANKL and osteoprotegerin-promoted alveolar remodeling. In conclusion, during the early stage of orthodontic tooth movement, corticotomy can accelerate the movement of teeth, modulate the state of bone metabolism, and activate osteogenesis and osteoclast, which support the theory of regional acceleratory phenomenon.

Localizing the osseous boundaries of micro-osteoperforations

INTRODUCTION

The aim of this work was to determine how far the effects of micro-osteoperforations (MOPs) extend within bone by quantifying the damage caused and the short-term bony adaptations that occur in and around the injury site.

METHODS

With the use of a split-mouth design, 34 MOPs (Propel) were randomly placed in the mandibular furcal bone of 13 beagle dogs either 2 or 4 weeks before killing them. The control side received no treatment. Vickers hardness microindentation, microscopic computed tomography, and histologic analyses were performed to evaluate the bone surrounding the MOPs.

RESULTS

Microfractures produced during insertion extended ∼0.6 mm from the MOP sites. Cortical and trabecular bone were significantly less dense on the experimental than on the control side up to 4.2 mm from the edge of the MOP, but side differences were small (<5%) beyond 1.5 mm from the MOP. Experimental cortical bone was significantly softer than the control bone up to 0.8 mm from the MOP after 2 weeks of healing, and up to 0.5 mm from the MOP after 4 weeks of healing. Hematoxylin and eosin stained sections of cortical and trabecular bone showed small areas of woven bone within the MOP sites after 2 weeks, and acellular areas of bone extending ∼0.5 mm from the MOP. After 4 weeks of healing, there were greater amounts of woven bone, as well as early signs of lamellar bone, in and around the MOP sites. Markedly increased TRAP activity extending up to 2.5 mm from the MOP was evident after 2 weeks, but not after 4 weeks. Vital fluorescence staining showed diffuse bone deposition on the experimental side up to 1.5 mm from the MOP margin.

CONCLUSIONS

When MOPs are performed in beagle dogs, demineralization is transient and healing of the injured area, as well as remineralization of bone affected by MOP placement, begins during the first 2 weeks. Although the transient effects extend farther, the principal effects extend only ∼1.5 mm from the MOP site.

Three-dimensional finite element analysis to evaluate biomechanical effects of different alveolar decortication approaches on rate of canine retraction

INTRODUCTION

The aim of this study was to compare different corticotomy approaches and determine their biomechanical effects on rate of canine displacement when compared to conventional orthodontics.

METHOD

Three-dimensional Finite Element Models with conventional non-corticotomy approach (model 1) and three corticotomy approaches ensuing buccal and palatal vertical cuts (model 2), interseptal bone reduction (model 3), buccal vertical cuts (model 4) were fabricated. Displacement of the canine and von Mises stresses in the canine and trabecular bone were calculated and compared under a distal retraction force of 1.5N.

RESULTS

The maximum displacement of canine with minimum anchorage loss was seen in model 3 followed by model 2, model 4 and model 1. The maximum equivalent (von Mises) stress was concentrated mainly on the distal side of canine in model 3 and had a uniform distribution of stresses on entire root surface.

CONCLUSIONS

Corticotomy approaches effectively accelerated maxillary canine retraction, exhibiting twice the rate of canine movement with minimum anchorage loss when compared to non-corticotomy approach. Corticotomy with interseptal bone reduction was most effective in terms of canine displacement and stress distribution.