Relationship between position of probe tip and periodontal tissues after periodontal surgery in dogs.

The aim of this study was to investigate postsurgical periodontal probe penetration by using clinical information and histometric data. Thirty-eight three-walled defects were created in four dogs, then maintained for 3 months. Subsequently, 26 defects were subjected to periodontal surgery (surgical group), while 12 defects served as controls. The dogs were sacrificed at 4, 8, 12, and 16 weeks. Immediately before sacrifice, endodontic silver points were placed in the gingival crevices as substitutes for periodontal probes and fixed on the teeth. Following block sections, histologic and histomorphometric evaluations were undertaken: location of the probe tip in relation to the apical termination of the junctional epithelium, length of new junctional epithelium in relation to the apical junctional epithelium, and mean length of connective tissue adhesion in relation to the apical junctional epithelium. Probe tips were located -1.37 +/- 1.73 mm and -0.20 +/- 0.15 mm apical to the apical junctional epithelium for the surgical and control groups, respectively, at 4 weeks, while the probe tip was located 0.58 +/- 0.31 mm and 0.40 +/- 0.20 mm coronal to the apical junctional epithelium, respectively, at 16 weeks. Length of new junctional epithelium in relation to apical junctional epithelium was significantly less for the surgical than the control group at 4 weeks (0.73 +/- 0.60 mm vs 1.19 +/- 0.02 mm) and 8 weeks (1.77 +/- 0.52 mm vs 2.15 +/- 0.00 mm). There were no significant differences between the groups in regard to connective tissue relationship to the apical junctional epithelium. Periodontal probing is not recommended for at least 2 months after surgical procedures; before this stage, probing forces may damage the soft tissue-tooth interrelationship.

Treatment of intrabony periodontal defects with enamel matrix derivative: a literature review.

The enamel matrix derivative (EMD) has been recently introduced in the periodontal field to overcome short-comings associated with currently available regenerative techniques. Information accumulated over the past years with application of EMD guided regeneration (EGR) in intrabony periodontal defects allowed a thorough evidence-based retrospective analysis. Clinical data from EMD controlled studies were pooled for meta-analysis and weighted according to the number of treated defects. Clinical attachment gain amounted to 3.2 +/- 0.9 mm (33% of the original attachment level) and probing reduction averaged 4.0 +/- 0.9 mm (50% of the baseline probing depth) for a total of 317 lesions with a mean baseline depth of 5.4 +/- 0.8 mm. Improvements in clinical parameters achieved with EMD were statistically significant in reference to preoperative measurements. However, despite the overall efficacy of EGR therapy, a significant variation in clinical outcomes was observed. Similar therapeutic results were reported in studies where EGR was compared directly to guided tissue regeneration. However, the controlled clinical trials did not have adequate statistical power to firmly support superiority or equivalency between the 2 regenerative therapies. The statistical superiority of EGR over treatment with open flap debridement has been established. Preliminary histologic investigations with surgically created defects and experimental periodontal lesions demonstrated the ability of EGR to induce formation of acellular cementum and promote significant anaplasis of the supporting periodontal tissues. The potential of EMD to encourage periodontal regeneration was also confirmed in human intrabony defects. However, recent human histologic studies have questioned both the consistency of the histologic outcomes and the ability of EGR to predictably stimulate formation of acellular cementum. Identifying clinical modifying parameters and understanding cellular interactions are apparently essential for the development of methodologies to enhance predictability and extent of EGR clinical and histologic results.