Effects of EMD in combination with bone swaging and calcium phosphate bone cement on periodontal regeneration in one-wall intrabony defects in dogs

Recent Clinical Treatment and Basic Research on the Alveolar Bone

The periodontal ligament is located between the bone (alveolar bone) and the cementum of the tooth, and it is connected by tough fibers called Sharpey’s fibers. To maintain healthy teeth, the foundation supporting the teeth must be healthy. Periodontal diseases, also known as tooth loss, cause the alveolar bone to dissolve. The alveolar bone, similar to the bones in other body parts, is repeatedly resorbed by osteoclasts and renewed by osteogenic cells. This means that an old bone is constantly being resorbed and replaced by a new bone. In periodontal diseases, the alveolar bone around the teeth is absorbed, and as the disease progresses, the alveolar bone shrinks gradually. In most cases, the resorbed alveolar bone does not return to its original form even after periodontal disease is cured. Gum covers the tooth surface so that it matches the shape of the resorbed alveolar bone, exposing more of the tooth surface than before, making the teeth look longer, leaving gaps between the teeth, and in some cases causing teeth to sting. Previously, the only treatment for periodontal diseases was to stop the disease from progressing further before the teeth fell out, and restoration to the original condition was almost impossible. However, a treatment method that can help in the regeneration of the supporting tissues of the teeth destroyed by periodontal diseases and the restoration of the teeth to their original healthy state as much as possible is introduced. Recently, with improvements in implant material properties, implant therapy has become an indispensable treatment method in dentistry and an important prosthetic option. Treatment methods and techniques, which are mainly based on experience, have gradually accumulated scientific evidence, and the number of indications for treatment has increased. The development of bone augmentation methods has contributed remarkably to the expansion of indications, and this has been made possible by various advances in materials science. The induced pluripotent stem cell (iPS) cell technology for regenerating periodontal tissues, including alveolar bone, is expected to be applied in the treatment of diseases, such as tooth loss and periodontitis. This review focuses on the alveolar bone and describes clinical practice, techniques, and the latest basic research.

A Novel Approach of Periodontal Osseous Wall Piezosplitting and Sequential Bone Expansion in Management of Localized Intra-Bony Defects with Wide Angulation—A Randomized Controlled Trial

Piezoelectric surgical instruments with various mini-sized tips and cutting technology offer a precise and thin cutting line that could allow the wider use of periodontal osseous wall swaging. This randomized controlled trial was designed to investigate the use of a minimally invasive piezo knife to harvest vascularized interseptal bone pedicles in treating intra-bony defects. Sixteen non-smoking patients (mean age 39.6 ± 3.9) with severe chronic periodontitis were randomly assigned into one of two groups (N = 8). The Group 1 (control) patients were treated by bone substitute grafting of the intra-bony defect, whereas the Group 2 patients were treated by intra-bony defect osseous wall swaging (OWS) combined with xenograft filling of the space created by bone tilting. In both groups, the root surfaces were treated with a neutral 24% EDTA gel followed by saline irrigation. Clinical and radiographic measurements were obtained at baseline and 6 months after surgery. The sites treated with osseous wall swaging showed a statistically significant probing-depth reduction and increase in clinical attachment compared with those of the Group 1 patients. The defect base level was significantly reduced for the OWS group compared to that of the Group 1 control. By contrast, the crestal bone level was significantly higher in the OWS group compared to Group 1. The crestal interseptal bone width was significantly higher in Group 2 at 6 months compared to the baseline value and to that of Group 1 (<0.001). The osseous wall swaging effectively improved the clinical hard- and soft-tissue parameters. The use of mini inserts piezo-cutting, sequential bone expanders for osseous wall redirection, and root surface EDTA etching appears to be a reliable approach that could allow the use of OWS at any interproximal dimension.

Regenerating Craniofacial Dental Defects With Calcium Phosphate Cement Scaffolds: Current Status and Innovative Scope Review

The management and treatment of dental and craniofacial injuries have continued to evolve throughout the last several decades. Limitations with autograft, allograft, and synthetics created the need for more advanced approaches in tissue engineering. Calcium phosphate cements (CPC) are frequently used to repair bone defects. Since their discovery in the 1980s, extensive research has been conducted to improve their properties, and emerging evidence supports their increased application in bone tissue engineering. This review focuses on the up-to-date performance of calcium phosphate cement (CPC) scaffolds and upcoming promising dental and craniofacial bone regeneration strategies. First, we summarized the barriers encountered in CPC scaffold development. Second, we compiled the most up to date in vitro and in vivo literature. Then, we conducted a systematic search of scientific articles in MEDLINE and EMBASE to screen the related studies. Lastly, we revealed the current developments to effectively design CPC scaffolds and track the enhanced viability and therapeutic efficacy to overcome the current limitations and upcoming perspectives. Finally, we presented a timely and opportune review article focusing on the significant potential of CPC scaffolds for dental and craniofacial bone regeneration, which will be discussed thoroughly. CPC offers multiple capabilities that may be considered toward the oral defects, expecting a future outlook in nanotechnology design and performance.

Clinical Outcomes after Regenerative Periodontal Therapy with Emdogain

Objective: Regeneration is defined as a reconstruction of a lost part of the body in such a way that the structure and function of the lost tissue are completely restored. The aim of this study is to compare the clinical outcomes of intrabony defects treatment using regenerative periodontal therapy with enamel matrix proteins (Emdogain, EMD) with a control group.

Methods: Ten patients with chronic periodontitis were included in this randomized, controlled clinical study. Two groups received conservative periodontal therapy. In the test group, different teeth received regenerative treatment with EMD. In the control group teeth received solely conservative periodontal therapy. Pocket depth probing (PD) and bone reduction (based on X rays) were registered at baseline and after eight months in both groups. In the control group

Results: Both groups showed a significant reduction of PD. The teeth treated with EMD showed a significant attachment gain. Within the test group, the radiographic examination of the teeth treated with EMD showed no significant change, whereas the teeth in the control group showed significant bone reduction.

Conclusions: Intrabony defects in teeth treaded with EMD exhibit a substantially higher gain in clinical attachment and defect filling. The use of EMD in dental practice can prevent further bone loss.

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.

Effect of methotrexate on the mechanical properties and microstructure of calcium phosphate cement

Calcium phosphate cement (CPC) is widely used as an antitumor bone-filling material. Methotrexate (MTX) is recognized as an effective chemotherapy medicine. The current study examined the effects of MTX on the mechanical properties and microstructure of CPC. Methotrexate-loaded CPC at mass ratios of 0%, 0.1%, 0.2%, and 0.5% were designated as groups A, B, C, and D, respectively, and were pressed into precast cylindrical molds. Solidification time, axial compressive strength, transverse compressive strength, and rotational tensile strength were measured, and scanning electron microscopy images were captured before and after MTX-CPC microstructure changes occurred. Average initial and final setting times increased gradually with increasing drug concentration, but this increase was not significant among the groups. Average axial transverse compressive strength and rotational tensile strength of groups B and C were not significantly different from those of group A (P>.05); however, there was a significant difference in these properties between groups A and D (P<.05). Scanning electron microscopy observations showed a porous crystalline structure. The addition of MTX to CPC does not significantly affect the basic crystal structure and setting time of CPC. Adding MTX at mass ratios of 0.1% and 0.2% to CPC does not lead to a significant difference in mechanical strength and can therefore be applied in clinical practice. This study may shed some light on the future application of MTX-loaded CPC in the treatment of bone defects after tumor excision.