Regeneration of the Periodontal Apparatus in Aggressive Periodontitis Patients

Periodontal Guided Tissue Regeneration Membranes: Limitations and Possible Solutions for the Bottleneck Analysis

Guided tissue regeneration (GTR) is an important surgical method for periodontal regeneration. By placing barrier membrane on the root surface of the tooth to guide the adhesion and proliferation of periodontal ligament cells, periodontal tissue regeneration can be achieved. This review intends to analyze the current limitations of GTR membranes and to propose possible solutions for developing new ones. Limitations of current GTR membranes include nonabsorbable membranes and absorbable synthetic polymer membranes exhibit weak biocompatibility; when applying to a large defect wound, the natural collagen membrane with fast degradation rate have limited mechanical strength, and the barrier function may not be maintained well. Although the degradation time can be prolonged after cross-linking, it may cause foreign body reaction and affect tissue integration; The clinical operation of current barrier membranes is inconvenient. In addition, most of the barrier membranes lack bioactivity and will not actively promote periodontal tissue regeneration. Possible solutions include using electrospinning (ELS) techniques, nanofiber scaffolds, or developing functional gradient membranes to improve their biocompatibility; adding Mg, Zn, and/or other metal alloys, or using 3D printing technology to improve their mechanical strength; increasing the concentration of nanoparticles or using directional arrangement of membrane fibers to control the fiber diameter and porosity of the membrane, which can improve their barrier function; mixing natural and synthetic polymers as well as other biomaterials with different degradation rates in proportion to change the degradation rate and maintain barrier function; to improve the convenience of clinical operation, barrier membranes that meets personalized adhesion to the wound defect can be manufactured; developing local controlled release drug delivery systems to improve their bioactivity. Impact statement This review provides an up-to-date summary of commonly commercial periodontal guided tissue regeneration membranes, and analyze their limitations in clinical use. Using studies published recently to explore possible solutions from several perspectives and to raise possible strategies in the future. Several strategies have tested in vivo/in vitro, which will guide the way to propel clinical translation, meeting clinical needs.

Therapeutic Functions of Stem Cells from Oral Cavity: An Update

Adult stem cells have been developed as therapeutics for tissue regeneration and immune regulation due to their self-renewing, differentiating, and paracrine functions. Recently, a variety of adult stem cells from the oral cavity have been discovered, and these dental stem cells mostly exhibit the characteristics of mesenchymal stem cells (MSCs). Dental MSCs can be applied for the replacement of dental and oral tissues against various tissue-damaging conditions including dental caries, periodontitis, and oral cancers, as well as for systemic regulation of excessive inflammation in immune disorders, such as autoimmune diseases and hypersensitivity. Therefore, in this review, we summarized and updated the types of dental stem cells and their functions to exert therapeutic efficacy against diseases.

Treatment of intrabony defects with modified perforated membranes in aggressive periodontitis: a 4-year follow-up of a randomized controlled trial

OBJECTIVE

(1) To assess long-term outcomes 4 years following guided tissue regeneration (GTR) of intrabony defects in patients diagnosed with aggressive periodontitis (AgP) and (2) to identify predictors of clinical attachment level (CAL) gain and bone/graft density gain.

MATERIALS AND METHODS

In 15 patients, two deep intrabony defects were randomly treated with xenogenic graft plus modified perforated membranes (MPM, tests) or xenogenic graft plus standard collagen membranes (CM, controls). After 4 years, clinical and radiographic outcomes were evaluated and compared with outcomes at baseline and after 1 year.

RESULTS

After 4 years, 14 test sites and 13 control sites were available for analysis. One tooth was lost as a result of root fracture. There were significant improvements in all evaluated parameters after 1 and 4 years in relation to baseline, but no differences were observed between tests and controls. However, some non-significant changes were found between 1 and 4 years. Regression analyses showed that recurrence of periodontitis was a significant predictor for CAL gain (p = 0.001) and bone/graft density gain (p = 0.024) from 1 to 4 years.

CONCLUSIONS

GTR of intrabony defects in AgP with either standard or modified CM yielded similarly successful and maintainable clinical benefits for compromised teeth 4 years following the surgery. The use of MPM showed no additional benefit.

CLINICAL RELEVANCE

This study demonstrates that most of the positive outcomes of GTR in AgP may be preserved over 4 years. Periodontitis recurrence might influence long-term outcomes.