Regional Acceleratory Phenomenon Research Articles

Innovative Periodontal Surgery by Monocortical Corticotomy in Management of Bimaxillary Protrusion Cases: A Clinical Study

ABSTRACT Periodontal accelerated osteogenic orthodontics (PAOO) is a procedure applying the clinical science of alveolar corticotomy, particulate bone grafting, and the application of orthodontic forces, for accentuated tooth movement. This is theoretically based on the bone healing pattern known as the regional acceleratory phenomenon (RAP). A series of 12 cases, including 8 females and 4 males, were included in the study. The cases were referred from the Department of Orthodontia to the Department of Periodontology, ADC (R&R), having bimaxillary protrusion with an increased overjet. After initial orthodontic alignment, buccal corticotomy procedure was planned. A full-thickness mucoperiosteal flap was reflected from maxillary canine to canine beyond the root apices. Vertical corticotomy cuts were given in the alveolar bone with piezo blades 2 mm apical to the crestal bone in the inter-radicular space midway between the root prominences and were joined by the horizontal cuts apically. Demineralized freeze-dried bone allograft (DFDBA) was placed in the surgical area. The flaps were sutured and pack was placed. Orthodontic retraction was started 2 weeks after the corticotomy procedure. Using this procedure, the treatment objectives were met in just half to one-third of the reported conventional treatment time and the large overjet was reduced to normal. Pre- and posttreatment clinical parameters were recorded, statistically analyzed, and corroborated with similar orthodontic treatment procedures without the use of the corticotomy technique. The present periodontal (PDL) intervention results in quick and stable results for the correction of bimaxillary protrusion cases. It enhances the esthetics and posttreatment orthodontic stability. How to cite this article Panwar M, Dubey D, Kosala M. Innovative Periodontal Surgery by Monocortical Corticotomy in Management of Bimaxillary Protrusion Cases: A Clinical Study. Int J Experiment Dent Sci 2017;6(2):55-60.

Periodontally accelerated osteogenic orthodontics

This case report demonstrates an orthodontic method that offers short treatment time and the ability to simultaneously reshape and increase the buccolingual thickness of the supporting alveolar bone. A 23-year-old female with Angle’s Class I moderately to severely crowded malocclusion with periodontal pocket with 31 and reduced thickness of the buccal cortical plate of lower anteriors, requested shortened orthodontic treatment time. This surgery technique included buccal full-thickness flaps, selective partial decortication of the cortical plates, concomitant bone grafting/augmentation, and primary flap closure. Following the surgery, orthodontic adjustments were made approximately every 2 weeks. From bracketing to debracketing, the case was completed in approximately 7 months and 3 weeks. Posttreatment evaluation of patient revealed good results. Preexisting thin labial bony cortical plate with lower anteriors was covered. This finding suggests credence to the incorporation of the bone augmentation procedure into the corticotomy surgery because this made it possible to complete the orthodontic treatment with a more intact periodontium. The rapid expansive tooth movements with no significant apical root resorption may be attributed to the osteoclastic or catabolic phase of the regional acceleratory phenomenon.

Osteoclastogenesis in Local Alveolar Bone in Early Decortication-Facilitated Orthodontic Tooth Movement.

ObjectiveIn the current study, we aimed to investigate the effects of alveolar decortication on local bone remodeling, and to explore the possible mechanism by which decortication facilitates tooth movement.Materials and MethodsForty rabbits were included in the experiment. The left mandible was subjected to decortication-facilitated orthodontics, and the right mandible underwent traditional orthodontics as a control. The animals were sacrificed on the days 1, 3, 5, 7 and 14, after undergoing orthodontic procedures. Tooth movement was measured by Micro-CT, and the local periodontal tissues were investigated using H&E, Masson's trichrome and tartrate-resistant acid phosphatase (TRAP) staining. The mRNA levels of genes related to bone remodeling in the alveolar bone were analyzed using real-time PCR.ResultOn days 3, 5, 7 and 14, tooth movement was statistically accelerated by decortication (P < 0.05) and was accompanied by increased hyperemia. Despite the lack of new bone formation in both groups, more osteoclasts were noted in the decorticated group, with two peak counts (P < 0.05). The first peak count was consistent with the maximum values of ctsk and TRAP expression, and the second peak counts accompanied the maximum nfatc1 and jdp2 expression. The increased fra2 expression and the ratio of rankl/opg also accompanied the second peak counts.ConclusionsFollowing alveolar decortication, osteoclastogenesis was initially induced to a greater degree than the new bone formation which was thought to have caused a regional acceleratory phenomenon (RAP). The amount of steoclastogenesis in the decorticated alveolar bone was found to have two peaks, perhaps due to attenuated local resistance. The first peak count in osteoclasts may have been due to previously existing osteoclast precursors, whereas the second may represent the differentiation of peripheral blood mononuclear cells which came from circulation as the result of hyperemia.

Root resorption following periodontally accelerated osteogenic orthodontics

Background Literature evidence suggests that root resorption, an adverse side effect of orthodontic therapy, may be decreased under conditions of alveolar osteopenia, a condition characterized by diminished bone density and created secondary to alveolar corticotomy (Cort) surgery. Purpose To compare root resorption of the maxillary central incisors following nonextraction orthodontic therapy with and without Cort surgery. Materials and Methods The sample comprised two groups, with and without Cort and was matched by age and gender: Cort-facilitated nonextraction orthodontics with 27 subjects, 53 central incisors of mean age 24.8 ± 10.2 years, and conventional (Conv) nonextraction orthodontics with 27 subjects, 54 incisors with mean age of 19.6 ± 8.8 years. All periapical radiographs were taken with the paralleling technique; total tooth lengths of the right and left central incisors were measured by projecting and enlarging the periapical radiographs exactly 8 times. Results t-tests revealed a significant decrease in treatment time in the Cort group (6.3 ± 8.0 vs. 17.4 ± 20.2 months,P = 0.000). Pretreatment root lengths were not significantly different (P = 0.11), but Conv had significantly shorter roots at posttreatment when compared with Cort (P = 0.03). Significant root resorption (P &lt; 0.01) occurred in both Cort (0.3 mm) and Conv (0.7 mm), but the increment of change was significantly greater in Conv (P &lt; 0.03). The variable SNA increased significantly in the Cort (P = 0.001) group and decreased significantly in the Conv group (P &lt; 0.001). Conclusions Based on the conditions of this study, it may be concluded that Cort-facilitated nonextraction orthodontic therapy results in less root resorption and enhanced alveolar support within a significantly reduced clinical service delivery time frame. Rapid orthodontic treatment and reduced apical root resorption are probably due to the transient osteopenia induced by the Cort surgery and inspired by regional acceleratory phenomenon.

Regional Acceleratory Phenomenon.

The regional acceleratory phenomenon (RAP) is a tissue reaction to a noxious stimulus that increases the healing capacities of the affected tissues. It is typical not only of hard tissues such as bone and cartilage, but also of soft tissues. The RAP is characterized by acceleration of the normal cellular activities, as an 'SOS' phenomenon of the body that has to respond to the new perturbation. In the alveolar bone, the RAP is characterized, at a cellular level, by increased activation of the basic multicellular units (BMUs), thereby increasing the remodeling space. At the tissue level, the RAP is characterized by the production of woven bone, with the typical unorganized pattern, that will be reorganized into lamellar bone at a later stage. In the alveolar bone, the RAP occurs typically in the healing process of the alveolar sockets after tooth extraction, in periodontal disease, after surgery and trauma and during orthodontic tooth movement. In relation to orthodontic tooth movement, the RAP can be seen as a tissue response to the mechanical cyclical perturbation that induces the formation of microdamage that has to be removed to avoid their accumulation and the following bone failure. The adaptation to the new orthodontically induced mechanical environment is ensured by an increased activation of the BMU that returns to normal levels after few months.

Centennial inventory: the changing face of orthodontics.

The American Journal of Orthodontics and Dentofacial Orthopedics celebrates its centennial, safeguarded by the nearly 115-year-old American Association of Orthodontists. This journey witnessed the rise and demise of various developments, concepts, and procedures, while basic knowledge is still needed. Various periods can be defined in the past century, but the goals remain to obtain more accurate diagnosis through precise anatomic imaging, more controlled and faster tooth movement, more discreet appliances, and the balance of esthetics, function, and stability. The most recent technologic advances have buttressed these goals. Cone-beam computed tomography has brought 3-dimensional assessment to daily usage, albeit the original enthusiasm is tempered by the risk of additional radiation. Temporary anchorage devices or miniscrews have revolutionized orthodontic practice and loom as a solid cornerstone of orthodontic science. Decortication and microperforation promise to speed up tooth displacement by stimulating vascularization. The concept of the regional acceleratory phenomenon has touched upon even the timing of orthognathic surgery. The burden of esthetic appliances remains, with the demand for "cosmetic" appliances and clear aligners. Have these developments changed the face of orthodontics? Have we engaged in another turn wherein certain treatment modalities may fade, while others join mainstream applications? These questions are addressed in this essay on the challenges, promises, and limitations of current orthodontic technology, enhancement of biologic response, and personalized treatment approaches.

An overview of surgery-first approach: Recent advances in orthognathic surgery.

The disadvantages of having orthodontic interventions both before and after orthognathic surgery include a long treatment time of 7–47 months and temporary worsening of facial appearance. Nowadays, the concept of surgery-first, followed by orthodontic treatment is applied to orthognathic surgery cases in different orthodontic centers in the world. This concept and technique is called “surgery-first-orthognathic-approach” or “surgery-first approach” (SFA) rigid fixation (skeletal anchorage system) of the bony segments and regional acceleratory phenomenon were keys to broad implementation of the SFA. This article is intended to provide an overview of SFA including indications, general and specific guidelines, different protocol variations, success rate and potential problems.

A Single Stage Surgically Facilitated Rapid Orthodontic Technique with Alveolar Bone Augmentation in the Treatment of Various Dental Malocclusions: Case Series

Background: Corticotomy when done on the bone over a root prominence can cause its demineralization, optimizing the response to applied orthodontic forces. This, when combined with augmentation of the alveolar bone can increase its volume and can also correct osseous dehiscences, and fenestrations over root surfaces. Here are cases that demonstrate the usefulness of periodontally accelerated orthodontic procedure in orthodontic treatment for the correction of various dental malocclusions. Materials and methods: Orthodontic tooth movement combined with elevation of full-thickness flap, selective decortication, and ostectomy of alveolar bone, followed by bone grafting to accomplish the desired complete orthodontic treatment. Results: The desired outcome of the PAOO as demonstrated by rapid tooth movement was observed in all the cases. Conclusion: An efficient and stable orthodontic tooth movement can be achieved with the periodotally accelerated osteogenic orthodontics technique. With this technique, the teeth can be moved in one third to one fourth the time required for traditional orthodontics alone. Maintaining an adequate blood supply is an essential element in this technique as this is a physiologically based treatment consistent with a regional acceleratory phenomenon.

Periodontally Assisted Osteogenic Orthodontic: Journey from Past to Present- a review

Now a days increasing number of adult patient come for Orthodontic treatment who wants their braces off as early as possible. Adults are more concerned about their aesthetics even with braces. To overcome this kind of psychological or psychosocial problem, new Orthodontic techniques have emerged to reduce treatment duration without compromising stability. There have been theories suggested by various authors for rapid tooth movement. One of such theories is periodontically accelerated osteogenic Orthodontics (PAOO) which is patented by Wilckodontics, which is said to harness the regional acceleratory phenomenon (RAP). PAOO technique definitely reduces treatment time than conventional orthodontic treatment. Studies also shows that, it increases alveolar bone thickness due to bone grafting, enhancing post orthodontic stability with lesser chances of root resorption.

Surgery First in Orthognathic Surgery: What Have We Learned? A Comprehensive Workflow Based on 45 Consecutive Cases

In some patients, "surgery first" (SF) may represent a reasonable approach for the expedited correction of a maxillofacial deformity. Based on the prospective evaluation of a large sample, this article provides a specific orthodontic and surgical protocol, discusses the benefits and limitations of this approach, and updates its indications. Forty-five patients were managed with an SF approach. Selected cases presented symmetrical skeletal malocclusions with no need for extractions or surgically assisted rapid palatal expansion. Periodontal or temporomandibular joint problems and management by an orthodontist without experience in orthognathic surgery were considered exclusion criteria. Virtual treatment planning included a 3-dimensional orthodontic setup. Standard orthognathic osteotomies were followed by buccal interdental corticotomies to amplify the regional acceleratory phenomenon. Miniscrews were placed for postoperative skeletal stabilization. Orthodontic treatment began 2 weeks after surgery. Archwires were changed every 2 to 3 weeks. At 12-month follow-up, patient satisfaction and orthodontist satisfaction were evaluated on a visual analog scale of 1 to 10. Descriptive statistics were computed for all study variables. The studied sample consisted of 27 women and 18 men (mean age, 23.5 yr). The main motivation for treatment was the wish to improve facial esthetics. Bimaxillary surgery was the most common procedure. Mean duration of orthodontic treatment was 37.8 weeks, with an average of 22 orthodontic appointments. Mean patient and orthodontist satisfaction scores were 9.4 (range, 8 to 10) and 9.7 (range, 8 to 10), respectively. The SF approach significantly shortens total treatment time and is very favorably valued by patients and orthodontists. Nevertheless, careful patient selection, precise treatment planning, and fluent bidirectional feedback between the surgeon and the orthodontist are mandatory.

Socket Preservation at Molar Site using Platelet Rich Fibrin and Bioceramics for Implant Site Development

ABSTRACTBackgroundThe extraction socket preservation technique conserves the alveolar architecture and prevents hard and soft tissue collapse that minimizes the necessity for future augmentation procedures. Also, considerable interest has recently emerged over the potential benefits of using platelet rich fibrin (PRF), a highly concentrated form of platelets power packed with growth factors encased in a leukocyte rich matrix that enhances osteogenic differentiation and bone repair. This article describes the currently improved technique utilizing alloplasts with autologous PRF to be implemented for preserving a future implant site.Materials and MethodsFollowing the atraumatic extraction of the periodontally compromised tooth, the socket bony walls were debrided and decorticated to facilitate regional acceleratory phenomenon. Venous blood was drawn from the antecubital fossa of the patient and was centrifuged according to Choukroun's method to yield autologous PRF that was minced into uniformly sized bits. Except for 2 to 3 mm of the coronal aspect of the socket, the rest was filled with particles of a slowly resorbing bone substitute material mixed homogeneously with minced PRF. A collagen membrane was used to seal the coronal end of the socket and was stabilized using 3-0 black braided silk sutures.ResultsClinically and radiographically satisfactory and successful regeneration of the deficient ridge's hard and soft tissues was demonstrated after 6 months post therapy.ConclusionSocket preservation surgery utilizing bioceramics and PRF is an effective procedure for posterior socket preservation coupled with rapid healing and aids in providing sound bone quality for successful implant placement.How to cite this articleGupta HS, Chowdhary KY, Pathak TS, Kini VV, Pereira R, Mistry A. Socket Preservation at Molar Site using Platelet Rich Fibrin and Bioceramics for Implant Site Development. J Contemp Dent 2013;3(2):102-107.

Accelerating Tooth Movement With Corticotomies: Is It Possible and Desirable?

Accelerating the rate of tooth movement is desirable to patients because it shortens treatment time and also to orthodontists because treatment duration has been linked to an increased risk of gingival inflammation, decalcification, dental caries, and root resorption. Corticotomies, which some orthodontists are currently using to speed up tooth movements, induce a regional acceleratory phenomenon, which provides the biological basis for accelerated tooth movement. Case reports and limited clinical studies show that corticotomies increase rates of tooth movement and decrease treatment duration. The experimental evidence indicates that corticotomies approximately double the amount of tooth movement produced with orthodontic forces. However, the experimental effects are limited to a maximum of 1-2 months in the canine model, suggesting that the effects of corticotomies in humans may be limited to 2-3 months, during which 4-6 mm of tooth movement might be expected to occur. Based on the available literature, performing corticotomies on a routine basis in private practices may not be justified. Controlled clinical studies are required to better understand the treatment and potential iatrogenic effect(s) of corticotomies. Accelerating the rate of tooth movement is desirable to patients because it shortens treatment time and also to orthodontists because treatment duration has been linked to an increased risk of gingival inflammation, decalcification, dental caries, and root resorption. Corticotomies, which some orthodontists are currently using to speed up tooth movements, induce a regional acceleratory phenomenon, which provides the biological basis for accelerated tooth movement. Case reports and limited clinical studies show that corticotomies increase rates of tooth movement and decrease treatment duration. The experimental evidence indicates that corticotomies approximately double the amount of tooth movement produced with orthodontic forces. However, the experimental effects are limited to a maximum of 1-2 months in the canine model, suggesting that the effects of corticotomies in humans may be limited to 2-3 months, during which 4-6 mm of tooth movement might be expected to occur. Based on the available literature, performing corticotomies on a routine basis in private practices may not be justified. Controlled clinical studies are required to better understand the treatment and potential iatrogenic effect(s) of corticotomies.

Surgery-first approach on patients with temporomandibular joint disease by intraoral vertical ramus osteotomy

Orthognathic surgery followed by postsurgical orthodontics without presurgical orthodontic treatment, known as the surgery-first approach (SFA), has become favored recently. The advantages of this surgical approach include total treatment time reduction, psychological benefit from a limited duration of unesthetic orthodontic appliances, and a more effective orthodontic movement of the dentition postoperatively through a regional acceleratory phenomenon. SFA has been previously described in the literature as a surgical technique with Le Fort I osteotomy and sagittal split ramus osteotomy (SSRO), which helps maintain postoperative occlusion with rigid fixation; however, patients with temporomandibular joint disorder (TMD) are better candidates for the intraoral vertical ramus osteotomy (IVRO) surgical technique instead of SSRO. The authors report 2 cases with excellent surgical outcomes and resolution of TMD symptoms on patients with mandibular prognathism via SFA using IVRO technique.

Le concept du déplacement dentaire accéléré par corticotomie ou par piézocision

The relatively recent introduction of corticotomies and piezocision has made it possible for orthodontists to accelerate tooth movement and thereby to shorten the length of orthodontic treatment. Specialists emphasizing a mechanistic concept have been debating the underlying basic biological mechanics of these new therapeutic tools with opposing specialists who support a biological conception. Our analysis of different publications on the subject suggests that the biological explanation, with its emphasis on the Regional Acceleratory Phenomenon (RAP), is correct. However, the majority of studies in this field are not based on the principle of evidence based medicine (EBM).

Microstruttura e funzione del tessuto osseo. Parte I: meccanismi di adattamento

ObjectivesThe aim of this study is to carry out a review of the bone micro-structure adaptive mechanisms and function in relation to dental applications. Materials and methodsThe relationship between bone micro-anatomical aspects and history of theoretical bone physiology has been evaluated in detail. ResultsThe modern theory of the physiology of bone is consistent with the integration among regional acceleratory phenomenon, Utah paradigm, and mechanostat hypothesis. Bone modeling and remodeling can respond to pleiotropic stimuli, including quantum concept of cell activation and dynamic loading. Finally, in the case of implants inserted in augmented bone with xenograft not completely resorbable biomaterials, a reduced mechanical competence of the peri-implant bone should be taken into account. ConclusionsThe static load, within the limits of proportionality, does not affect bone resorption. To facilitate the “local acceleratory phenomenon” after implant bed preparation and during implant placement the blood clot should be preserved by any irrigation procedure. Progressive loading procedures should be used for implants placed in augmented bone with xenograft biomaterials with incomplete resorption behavior.

Residents' journal review

Residents' journal review

Periodontally accelerated osteogenic orthodontics (PAOO) - a review

With an increasing number of adult patients coming to the orthodontic clinic, the orthodontic professional is constantly looking for ways to accelerate tooth movement. Surgical intervention to affect the alveolar housing and tooth movement has been described in various forms for over a hundred years. However, it is the spirit of interdisciplinary collaboration in orthodontics has expanded the realm of traditional orthodontic tooth movement protocols. Periodontal accelerated osteogenic orthodontics (PAOO) is a clinical procedure that combines selective alveolar corticotomy, particulate bone grafting, and the application of orthodontic forces. This procedure is theoretically based on the bone healing pattern known as the regional acceleratory phenomenon (RAP). PAOO results in an increase in alveolar bone width, shorter treatment time, increased post treatment stability, and decreased amount of apical root resorption. Tooth movement can be enhanced and cases completed with increased alveolar volume providing for a more intact periodontium, decreased need for extractions, degree of facial remodeling and increased bone support for teeth and overlying soft tissues, thereby augmenting gingival and facial esthetics.The purpose of this article is to describe the history, biology, clinical surgical procedures, indications, contraindications and possible complications of the PAOO procedure. Key words:Periodontics, corticotomy, osteogenic, orthodontics.

Observation of trabecular changes of the mandible after orthognathic surgery using fractal analysis

Objectives: This study sought to evaluate trabecular changes in the mandible using fractal analysis and to explain the transient osteopenia related to rapid orthodontic tooth movement after orthognathic surgery. Materials and Methods: Panoramic radiographs were taken of 26 patients who underwent bilateral sagittal split ramus osteotomy. Radiographs taken before the surgery and 1 month after surgery were overlapped, and 40×40 pixel square regions of interest were selected near the mandibular canines and 1st molars. After the image processing procedure, the fractal dimension was calculated using the box-counting method. Results: Fractal dimension after orthognathic surgery decreased in a statistically significant manner (P Conclusion: This study found that bone density decreases after orthognathic surgery due to transient osteopenia related to the regional acceleratory phenomenon. This result can provide a guide to evaluating orthodontic tooth movement after orthognathic surgery.

The Role of Collagen Membrane as a Scaffold of Etchant for Regional Acceleratory Phenomenon

Purpose: The goal of this research is to find the role of collagen membrane, which can reduce physical damage, as a scaffold for possible alternative to the corticotomy which causes Regional Acceleratory Phenomenon (RAP). Materials and Methods: The experiments were carried out on 12 New Zealand white rabbits, approximately 3.5 kg in bodyweight. We made an incision on the skin of the mandibular border and applied 37% phosphoric acid and collagen membrane to the mandibular bone surface of the first group (experimental group), and only phosphoric acid to the second group (control group). After 3 days, 1 week, and 2 weeks, 4 rabbits each were sacrificed and specimens were obtained. Each specimen was stained by H&E and Tartrate-resistant acid phosphatase (TRAP), and histological changes were observed by light microscope. Results: The demineralization of the experimental group was weak compared to the control group. It also showed a gradual increase of demineralization (after 3 days, 1 week, and 2 weeks) and the control group showed more extensive demineralization than the experimental group. Conclusion: This study demonstrates the amount of demineralization as a result of using phosphoric acid, and as time went by, demineralization increased. The absorbable collagen membrane was used as a scaffold to increase bone demineralization effect and prevent dispersion to adjacent tissues, but rather the amount of bone demineralization decreased. Therefore, the role of collagen membrane as a scaffold for RAP was weak.

Comparison of corticotomy-facilitated vs standard tooth-movement techniques in dogs with miniscrews as anchor units

One method used to accelerate orthodontic tooth movement is the corticotomy-facilitated (CF) technique. The purposes of this study were to (1) identify the effect of the CF technique on orthodontic tooth movement compared with the standard technique, and (2) explore the histologic basis of the difference between the 2 techniques. Six dogs, aged 6 to 9 months, were used in this study. Extraction of the maxillary second premolar and miniscrew placement were done bilaterally in the maxilla. On the right side, the corticotomy was performed. The first premolars were distalized against the miniscrews with nickel-titanium coil springs on both sides. One dog was killed each week after orthodontic force application. The first premolar on the CF side moved significantly more rapidly (P <0.05). Histologic findings showed more active and extensive bone remodeling on both the compressive and tension sides in the CF group. The CF technique doubled the rate of orthodontic tooth movement. Histologically, the more active and extensive bone remodeling in the CF group suggested that the acceleration of tooth movement associated with corticotomy is due to increased bone turnover and based on a regional acceleratory phenomenon.