Formation Of New Attachment Research Articles

Histological evaluation of nonsurgical periodontal treatment with and without the use of sodium hypochlorite / amino acids and cross-linked hyaluronic acid gels in dogs

ObjectivesTo evaluate periodontal wound healing following scaling and root planing (SRP) in conjunction with the application of sodium hypochlorite/amino acids and cross-linked hyaluronic acid (xHyA) gels in dogs.Materials and MethodsIn four beagle dogs, 2-wall intrabony defects were created and metal strips were placed around the teeth. Clinical parameters were measured 4 weeks after plaque accumulation. The experimental root surfaces were subjected to SRP with either the subgingival application of a sodium hypochlorite/amino acid gel and a xHyA gel (test group) or SRP alone (control group) using a split-mouth design. Clinical parameters were re-evaluated at 6 weeks. The animals were sacrificed at 8 weeks for histological analysis.ResultsThe test group showed significant improvements in all clinical parameters compared to the control group. Histologically, the test group exhibited statistically significantly greater new bone formation [i.e., length of newly formed bone, new bone area] compared with the control group (p < 0.05). Furthermore, statistically significantly greater formation of new attachment [i.e., linear length of new cementum adjacently to newly formed bone with inserting collagen fibers] and new cementum was detected in the test group compared with the control group at 8 weeks (p < 0.05 and p < 0.01, respectively).ConclusionThe adjunctive subgingival application of sodium hypochlorite/amino acid and xHyA gels to SRP offers an innovative novel approach to enhance periodontal wound healing/regeneration.Clinical relevanceThe present findings have for the first-time shown histologic evidence for periodontal regeneration in support of this novel treatment modality.

Intentional Replantation as the Treatment of Left Mandibular Second Premolar Refractory Periapical Periodontitis: A Case Report

Introduction This report aims to assess the feasibility of intentional replantation combined with concentrated growth factor(CGF) membrane treatment for refractory apical periodontitis of the left mandibular second premolar (35), with a 13-month follow-up period. Case Report A 24-year-old female patient underwent root canal treatment for pulpitis of the left mandibular second premolar 3 years ago, and her gum repeatedly swelled and drained pus after the treatment. CBCT revealed that the apical area of 35 was adjacent to mental foramina, and the cyst range was large. There could be issues of poor visual field, trauma, difficulty in apical preparation and backfilling after the apical resection. The left mandibular second premolar (35) was extracted, and the inflammatory tissues in the apical and alveolar fossa were removed, followed by the removal of apical irritants. The extracted premolar was then implanted into the alveolar fossa and fixed. Results and Prognosis After a duration of 13 months, the left mandibular second premolar 35 exhibited no clinical symptoms and was able to perform normal masticatory function. There was an absence of gum swelling, pain or mobility; cone beam computed tomography imaging revealed bone regeneration below the root apex with the absence of new lesions, root resorption, or adhesion to the alveolar bone. The periodontal ligament demonstrated healing between the root and alveolar bone, effectively controlling infection, preserving infected teeth and facilitating the formation of new attachments around them. Discussion Intentional tooth replantation has some advantages, like short operation time, less cost, less bone injury, and less limitations in terms of anatomy and location. However, clinicians should consider whether intentional replantation could be performed before dental implantation for the affected teeth with intractable periapical lesions. Nonetheless, its efficacy needs further evaluations through long-term clinical follow-ups.

Comparative study of effects of Triphala and Tetracycline gel on root conditioning

Background: Remnants of dental calculus, contaminated cementum, and subgingival plaque act as a physical barrier between periodontal tissues and root surfaces, which inhibits the formation of new attachment. Treatment of denuded root surface using various chemicals and antimicrobial agents with scaling and root planing helps in active periodontal regeneration. Aim: The aim of this study was to evaluate and compare the demineralizing effects of Triphala and 1% Tetracycline HCl gel on root conditioning using a Scanning Electron Microscope. Settings and design: A total of 50 hemi-sectioned root samples were obtained from 25 extracted, and root planed samples. These were divided into two groups, Group 1: 1% Tetracycline HCl gel and Group 2: Triphala. Materials and method: The two root conditioning agents were applied with cotton pellets on the sectioned roots. The samples were then examined under the scanning electron microscope. Statistical analysis used: Data obtained was compiled on a MS Office Excel Sheet. Inter group comparison was done using Mann Whitney U test. Comparison of frequencies of categories of variables with groups was done using Chi Square Test. Results: The root conditioning agents used in this study were found to be equally effective in removing the smear layer. &#x0D;

SDF-1 modulates periodontal ligament-Mesenchymal Stem Cells (pdl-MSCs).

In this in vitro study, the effects of Stromal cell-derived factor-1 (SDF-1) was evaluated on the periodontal ligament-Mesenchymal Stem Cells (pdl-MSCs) functions. Real-time cell analyzer-single plate (RTCA-SP) was employed for proliferation, and RTCA-dual purpose (DP) was utilized for pdl-MSCs migration potential treated with different SDF-1 concentrations (0, 0.1, 1, 10, 100, 200, and 400ng/ml). Based on the dose-response findings, 10ng/ml SDF-1 was used for further mRNA experiments. RNAs isolated at 6 and 24h were checked using quantitative RT-PCR for mineralized tissue-associated genes including type I collagen (COL I), osteocalcin (OCN), osteopontin (OPN), and runt-related transcription factor 2 (Runx2). cRNA was synthesized for 6h, and whole-genome array analysis was performed for over 47.000 probes. Data were subjected to quantile normalization before analysis. Increased proliferation and migration were observed in pdl-MSCs treated with 0.1, 1, and 10ng/ml SDF-1. Increased COL I was observed at both time points: 6 and 24h. While there was no significant change for OCN, OPN, and Runx2 at 6h, SDF-1 up-regulated OCN and OPN, but down-regulated Runx2 mRNA expressions at 24h. IL-8 and ESM1 genes were differentially expressed over twofold when the pdl-MSCs were exposed to SDF-1 at whole-genome array analysis. IL-8 induction was confirmed with RT-PCR. Findings of this study displayed that SDF-1 modulated pdl-MSCs which were important for periodontal regeneration, inducing migration and proliferation, and regulating extracellular matrix synthesis in favor of the formation of new attachment.

Periodontal wound healing/regeneration of two-wall intrabony defects following reconstructive surgery with cross-linked hyaluronic acid-gel with or without a collagen matrix: a preclinical study in dogs.

In-vitro data have shown that cross-linked hyaluronic acid (HA) enhances the proliferative and migratory properties of cells involved in periodontal wound healing/regeneration, stabilizes the blood clot, reduces the inflammatory response, and facilitates angiogenesis. The aim of this study was to histologically evaluate the effects of cross-linked HA alone or combined with a collagen matrix (CM) on the periodontal wound healing/regeneration in intrabony defects. Two-wall intrabony defects (5 mm wide, 5 mm deep) were surgically created at the distal and mesial aspects of mandibular premolars in six beagle dogs. The 24 defects were randomly treated as follows: open flap debridement (OFD) + HA, OFD + CM, OFD + HA + CM (HA/CM), and OFD alone (control). At 2 months, the animals were euthanized for histologic evaluation. The HA (2.43 ± 1.25 mm) and HA/CM (2.60 ± 0.99 mm) groups yielded statistically significantly (P &lt; .05) greater formation of new attachment (ie, linear length of new cementum adjacent to newly formed bone, with inserting collagen fibers) compared with the OFD (0.55 ± 0.99 mm) group. Among the four treatment groups, the HA/CM group demonstrated the highest amount of regenerated tissues, although no statistically significant differences in any of the histometric parameters were observed between the HA and HA/CM groups. Within their limits, it can be concluded that cross-linked HA alone or combined with CM promotes periodontal wound healing/regeneration in two-wall intrabony defects in dogs.

Establishing correct kinetochore-microtubule attachments in mitosis and meiosis.

Faithful chromosome segregation in mitosis and meiosis requires that chromosomes properly attach to spindle microtubules. Initial kinetochore-microtubule attachments are often incorrect and rely on error correction mechanisms to release improper attachments, allowing the formation of new attachments. Aurora B kinase and, in mammalian germ cells, Aurora C kinase function as the enzymatic component of the Chromosomal Passenger Complex (CPC), which localizes to the inner centromere/kinetochore and phosphorylates kinetochore proteins for microtubule release during error correction. In this review, we discuss recent findings of the molecular pathways that regulate the chromosomal localization of Aurora B and C kinases in human cell lines, mice, fission yeast, and budding yeast. We also discuss differences in the importance of localization pathways between mitosis and meiosis.

Comparison of Different Periodontal Healing of Critical Size Noncontained and Contained Intrabony Defects in Beagles.

Background:Regenerative techniques help promote the formation of new attachment and bone filling in periodontal defects. However, the dimensions of intraosseous defects are a key determinant of periodontal regeneration outcomes. In this study, we evaluated the efficacy of use of anorganic bovine bone (ABB) graft in combination with collagen membrane (CM), to facilitate healing of noncontained (1-wall) and contained (3-wall) critical size periodontal defects.Methods:The study began on March 2013, and was completed on May 2014. One-wall (7 mm × 4 mm) and 3-wall (5 mm × 4 mm) intrabony periodontal defects were surgically created bilaterally in the mandibular third premolars and first molars in eight beagles. The defects were treated with ABB in combination with CM (ABB + CM group) or open flap debridement (OFD group). The animals were euthanized at 8-week postsurgery for histological analysis. Two independent Student's t-tests (1-wall [ABB + CM] vs. 1-wall [OFD] and 3-wall [ABB + CM] vs. 3-wall [OFD]) were used to assess between-group differences.Results:The mean new bone height in both 1- and 3-wall intrabony defects in the ABB + CM group was significantly greater than that in the OFD group (1-wall: 4.99 ± 0.70 mm vs. 3.01 ± 0.37 mm, P < 0.05; 3-wall: 3.11 ± 0.59 mm vs. 2.08 ± 0.24 mm, P < 0.05). The mean new cementum in 1-wall intrabony defects in the ABB + CM group was significantly greater than that in their counterparts in the OFD group (5.08 ± 0.68 mm vs. 1.16 ± 0.38 mm; P < 0.05). Likewise, only the 1-wall intrabony defect model showed a significant difference with respect to junctional epithelium between ABB + CM and OFD groups (0.67 ± 0.23 mm vs. 1.12 ± 0.28 mm, P < 0.05).Conclusions:One-wall intrabony defects treated with ABB and CM did not show less periodontal regeneration than that in 3-wall intrabony defect. The noncontained 1-wall intrabony defect might be a more discriminative defect model for further research into periodontal regeneration.

Perkembangan Terkini Membran Guided Tissue Regeneration/Guided Bone Regeneration sebagai Terapi Regenerasi Jaringan Periodontal

Periodontitis adalah salah satu penyakit patologis yang mempengaruhi integritas sistem periodontal yang menyebabkan kerusakan jaringan periodontal yang berlanjut pada kehilangan gigi. Beberapa tahun belakangan ini banyak ketertarikan untuk melakukan usaha regenerasi jaringan periodontal, tidak saja untuk menghentikan proses perjalanan penyakit namun juga mengembalikan jaringan periodontal yang telah hilang. Sasaran dari terapi regeneratif periodontal adalah menggantikan tulang, sementum dan ligamentum periodontal pada permukaan gigi yang terkena penyakit. Prosedur regenerasi antara lain berupa soft tissue graft, bone graft, biomodifikasi akar gigi, guided tissue regeneration sertakombinasi prosedur-prosedur di atas, termasuk prosedur bedah restoratif yang berhubungan dengan rehabilitasi oral dengan penempatan dental implan. Pada tingkat selular, regenerasi periodontal adalah proses kompleks yang membutuhkan proliferasi yang terorganisasi, differensiasi dan pengembangan berbagai tipe sel untuk membentuk perlekatan periodontal. Rasionalisasi penggunaan guided tissue regeneration sebagai membran pembatas adalah menahan epitel dan gingiva jaringan pendukung, sebagai barrier membrane mempertahankan ruang dan gigi serta menstabilkan bekuan darah. Pada makalah ini akan dibahas sekilas mengenai 1. Proses penyembuhan terapi periodontal meliputi regenerasi, repair ataupun pembentukan perlekatan baru. 2. Periodontal spesific tissue engineering. 3. Berbagai jenis membran/guided tissue regeneration yang beredar di pasaran dengan keuntungan dan kerugian sekaligus karakteristik masing-masing membran. 4. Perkembangan membran terbaru sebagai terapi regenerasi penyakit periodontal. Tujuan penulisan untuk memberi gambaran masa depan mengenai terapi regenerasi yang menjanjikan sebagai perkembangan terapi penyakit periodontal. Latest Development of Guided Tissue Regeneration and Guided Bone Regeneration Membrane as Regenerative Therapy on Periodontal Tissue. Periodontitis is a patological state which influences the integrity of periodontal system that could lead to the destruction of the periodontal tissue and end up with tooth loss. Currently, there are so many researches and efforts to regenerate periodontal tissue, not only to stop the process of the disease but also to reconstruct the periodontal tissue. Periodontal regenerative therapy aims at directing the growth of new bone, cementum and periodontal ligament on the affected teeth. Regenerative procedures consist of soft tissue graft, bone graft, roots biomodification, guided tissue regeneration and combination of the procedures, including restorative surgical procedure that is connected with oral rehabilitation with implant placement. At cellular phase, periodontal regeneration is a complex process with well-organized proliferation, distinction, and development of various type of cell to form attachment of periodontal tissue. Rationalization of the use of guided tissue regeneration as barrier membrane is to prohibit the penetration of epithelial and connective tissue migration into the defect, to maintain space, and to stabilize the clot. This research discusses: 1. Healing process on periodontal therapy including regeneration, repair or formation of new attachment. 2. Periodontal specific tissue engineering. 3. Various commercially available membrane/guided tissue regeneration in the market with its advantages and disadvantages and their characteristics. 4. Recent advancement of membrane as regenerative therapy on periodontal disease. In addition, this review is presented to give an outlook for promising regenerative therapy as a part of developing knowledge and skills to treat periodontal disease.

The efficacy of bone replacement grafts in the treatment of periodontal osseous defects. A systematic review.

Bone replacement grafts (BRG) are widely used in the treatment of periodontal osseous defects; however, the clinical benefits of this therapeutic practice require further clarification through a systematic review of randomized controlled studies. The purpose of this systematic review is to access the efficacy of bone replacement grafts in proving demonstrable clinical improvements in periodontal osseous defects compared to surgical debridement alone. What is the effect of bone replacement grafts compared to other interventions on clinical, radiographic, adverse, and patient-centered outcomes in patients with periodontal osseous defects? The computerized bibliographical databases MEDLINE and EMBASE were searched from 1966 and 1974, respectively, to October 2002 for randomized controlled studies in which bone replacement grafts were compared to other surgical interventions in the treatment of periodontal osseous defects. The search strategy included screening of review articles and reference lists of retrieved articles as well as hand searches of selected journals. All searches were limited to human studies in English language publications. Non-randomized observational studies (e.g., case reports, case series), publications providing summary statistics without variance estimates or data to permit computation, and studies without BRG intervention alone were excluded. The therapeutic endpoints examined included changes in bone level, clinical attachment level, probing depth, gingival recession, and crestal resorption. For purposes of meta-analysis, change in bone level (bone fill) was used as the primary outcome measure, measured upon surgical re-entry or transgingival probing (sounding). 1. Forty-nine controlled studies met eligibility criteria and provided clinical outcome data on intrabony defects following grafting procedures. 2. Seventeen studies provided clinical outcome data on BRG materials for the treatment of furcation defects. 1. With respect to the treatment of intrabony defects, the results of meta-analysis supported the following conclusions: 1) bone grafts increase bone level, reduce crestal bone loss, increase clinical attachment level, and reduce probing depth compared to open flap debridement (OFD) procedures; 2) No differences in clinical outcome measures emerge between particulate bone allograft and calcium phosphate (hydroxyapatite) ceramic grafts; and 3) bone grafts in combination with barrier membranes increase clinical attachment level and reduce probing depth compared to graft alone. 2. With respect to the treatment of furcation defects, 15 controlled studies provided data on clinical outcomes. Insufficient studies of comparable design were available to submit data to meta-analysis. Nonetheless, outcome data from these studies generally indicated positive clinical benefits with the use of grafts in the treatment of Class II furcations. 3. With respect to histological outcome parameters, 2 randomized controlled studies provide evidence that demineralized freeze-dried bone allograft (DFDBA) supports the formation of a new attachment apparatus in intrabony defects, whereas OFD results in periodontal repair characterized primarily by the formation of a long junctional epithelial attachment. Multiple observational studies provide consistent histological evidence that autogenous and demineralized allogeneic bone grafts support the formation of new attachment. Limited data also suggest that xenogenic bone grafts can support the formation of a new attachment apparatus. In contrast, essentially all available data indicate that alloplastic grafts support periodontal repair rather than regeneration. 4. The results of this systematic review indicate that bone replacement grafts provide demonstrable clinical improvements in periodontal osseous defects compared to surgical debridement alone.

The effect of insulin-like growth factor-I and human growth hormone on periodontal ligament fibroblast morphology, growth pattern, DNA synthesis, and receptor binding.

Repopulation of the detached root surface by cells from the periodontal ligament (PDL) is a prerequisite for new attachment formation. Stimulation of PDL-cell growth may therefore serve as an essential method to enhance formation of new attachment. Studies have demonstrated that insulin-like growth factor-I (IGF-I) has a mitogenic effect on fibroblasts originating from various connective tissues and cell-lines. Further, human growth hormone (hGH) is known to regulate the plasma concentration of IGF-I and to mediate cellular biological effects. In the present study we examined the effect of IGF-I and hGH on morphology, growth pattern, and DNA synthesis. The expression of IGF-I and hGH receptors on the surface of cultured PDL fibroblasts is also described. A primary fibroblastic cell line was established from rat PDL tissue, and blind, photographic recordings of morphology and growth pattern, as well as incorporation of [3H]thymidine in cellular DNA, was carried out in the presence and absence of IGF-I and hGH. The presence of specific membrane receptors was investigated by binding of [125I]IGF-I and [125I]hGH. The analysis of photographs showed that IGF-I and hGH had no effect on morphology and growth pattern. Incorporation of 3H-thymidine, however, was increased in a dose-dependent manner by IGF-I, whereas hGH alone or in combination with IGF-I produced no dose-dependent response. Maximum effect (% of control) on DNA synthesis was 176% for IGF-I and 91% for hGH.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of granulation tissue, dental calculus and contaminated root cementum on periodontal wound healing

The rôle of gingival granulation tissue, dental calculus and contaminated root cementum in marginal periodontal formation of new attachment was studied experimentally after chemical conditioning of the root surfaces of premolars and molars in 8 monkeys. Each treatment procedure was carried out in 4 monkeys. The other 4 monkeys served as controls. A morphometrical method was used to evaluate the results. It was concluded that a significant amount of new attachment including formation of new adhering cementum will result only on chemically-conditioned cementum surfaces. Small amounts of calculus or granulation tissue left in situ do not seem to influence healing, provided the cementum is left intact after chemical cleansing.

Effect of crown‐attached sutures on healing of experimental furcation defects in dogs

This study evaluates whether suturing of replaced flaps with crown-attached sutures, following reconstructive surgery, counteracts postoperative recession of the gingival margins and facilitates new attachment. Through-and-through furcation defects were created in the mandibular premolars of 5 beagle dogs. Bone was surgically removed from the furcation and around each root to a level 3 to 4 mm below the cemento-enamel junction. Steel wires were placed in the furcations for 6 weeks to enhance plaque formation. After 12 weeks, reconstructive surgery that included acid conditioning of root surfaces was performed. On 1 side of the mandible, the flaps were replaced and secured by bonding the sutures to the teeth with composite resin. On the other side, the replaced flaps were sutured interdentally with single sutures. The results demonstrated that the margins of flaps secured with interdental sutures shifted apically to the fornix of the furcations after 1 week, and histologically all 10 furcations were found to be lined with epithelium. Margins of flaps secured with crown-attached sutures remained an average of 0.5 mm coronally to the fornix, and 13 of the 14 teeth showed new attachment. The results indicate that a suturing technique which counteracts gingival recession, favours the formation of new attachment in this beagle dog model.

LOCOMOTORY POWERS OF ADULT ASCIDIANS

Adults of several species of both solitary and colonial ascidians are capable of slow crawling, involving the progressive formation of new attachments and tearing or dissolving the old ones. The ampullae play a leading part. A moving colony may divide into two, or two adjacent colonies may fuse: true fusion has been observed only once, in Trididemnum tenerum. Both Ciona intestinalis and Diplosoma listerianum may metamorphose by attachment to the surface film and are capable of post‐metamorphic attachment to a solid surface for a prolonged period. In such attachment the ampullae play a leading role. A free‐swimming (unattached) colony of Diplosoma takes on the form of a Pyrosoma colony. Such colonies have been reared in the laboratory forming cigar‐shaped, jet‐propelled bodies up to 1 cm. long with as many as fifty zooids.