Trace registration is a new, alternative registration method for dynamic navigation implant surgery that eliminates the need for an artificial fiducial marker and stent to be present in the CBCT scan, substituting it with other high-contrast landmarks such as teeth, implants, or abutments. Clinical advantages include a streamlined, simplified workflow with fewer opportunities for error; elimination of presurgical steps associated with stent fabrication and imaging; and reduction in radiation risk. Sufficient high-contrast intraoral structures are a prerequisite for using this technique. This case series presents the trace registration protocol and workflow and reports on cases that demonstrate the application of this technology, including postoperative placement accuracy evaluation.

Growth factors have been used in numerous oral applications to aid in bone formation after tooth extraction. Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-b superfamily and are involved in the differentiation of pluripotent mesenchymal cells, leading to new bone formation through osteoblastic induction. This study examined histologic wound healing following extraction and ridge preservation using recombinant human BMP-2 (rhBMP-2) and a collagen sponge. Formation of new vital bone was seen, suggesting that this material is a viable option for ridge preservation in preparation for implant placement.

The design of an implant-abutment interface may have an impact on the peri-implant soft tissue esthetics. In an ongoing randomized controlled trial (RCT) with 141 participants, the authors evaluated the peri-implant tissue responses around three different implant-abutment interface designs used to replace single teeth in the esthetic zone. The aim of this report is to describe the treatment protocol utilized in this ongoing RCT by (1) demonstrating in detail a clinical case treated under this protocol and (2) reporting peri-implant soft tissue responses in a cohort of 12 representative cases from the RCT at 1-year follow-up. Male and female adults requiring single implants in the anterior maxilla were enrolled in the RCT according to the study protocol. Five months following any required extraction and/or socket bone grafting/ridge augmentation, one of the following three implant-abutment interfaces was placed and immediately provisionalized: (1) conical interface (CI; OsseoSpeed, Dentsply Implants), n = 4; (2) flat-to-flat interface (FI; NobelSpeedy Replace, Nobel Biocare), n = 4; or (3) platform-switch interface (PS; NanoTite Certain Prevail, Biomet 3i), n = 4. Twelve weeks later, definitive crowns were delivered. Throughout the treatment, peri-implant buccal gingival zenith height and mesial/distal papilla height were measured on stereotactic device photographs, and pink esthetic scores (PES) were determined. The demographics of the participants in each of the three implant-abutment interface groups were very similar. All 12 study sites had ideal ridge form with a minimum width of 5.5 mm following implant site development performed according to the described treatment protocol. Using this treatment protocol for single-tooth replacement in the anterior maxilla, the clinicians were able to obtain esthetic peri-implant soft tissue outcomes with all three types of implant-abutment interface designs at 1-year follow-up as shown by the Canfield data and PES. The proposed treatment protocol for single-tooth replacement in the esthetic zone provides a reliable method to obtain and assess the esthetic outcome as a function of implant-abutment interface design and is now in its fifth year of follow-up.

In an attempt to reduce postextraction alveolar bone resorption, ridge preservation grafting procedures with or without resorbable membranes have become standard-of-care treatments following tooth removal. This prospective case series examined histologic and clinical outcomes following socket grafting with a syringeable paste allograft and a resorbable extracellular matrix membrane at three different time periods following postextraction grafting: 6, 12, and 24 weeks. At each time period, bone core specimens were retrieved for microscopic examination, and implants were placed. Following prosthetic restoration, implants were monitored under long-term occlusal function. At all three time periods, histologic results revealed active bone regeneration. At 6 weeks, localized areas of woven bone were evident, although nonmineralized osteoid was the dominant feature. At 12 and 24 weeks, regenerated woven bone dominated the histologic landscape, with increasing amounts evident in the latter specimens. Regardless of when implants were placed following grafting, implant survival under function occurred.

As part of the paradigm shift toward more minimally invasive surgical procedures, increasing numbers of references to laser-mediated flapless crown lengthening are noted in the published literature. The vast majority of these references are noncontrolled case reports or technique-focused articles. Therefore, prospective, randomized controlled studies that objectively examine the safety and efficacy of flapless crown lengthening are lacking. The current case series represents an initial attempt to examine some of the clinical issues posed by this minimally invasive flapless approach. Ultimately, only welldesigned controlled clinical trials can yield the type of evidence-based data necessary to categorize this approach to crown lengthening as standard-ofcare treatment.

The current study examined the histologic and microcomputed tomographic (micro CT) outcomes of the treatment of gingival recession defects with either a subepithelial connective tissue graft (CTG) or 0.3 mg/mL recombinant human platelet-derived growth factor (rhPDGF-BB) on a beta tricalcium phosphate (ß-TCP) matrix. Gingival recession defects were surgically created in six premolar teeth with no more than 3 mm of keratinized marginal tissue, an osseous crest 2 to 3 mm apical to the newly created gingival margin, and recession depth of at least 3 mm. The defects were left untouched for 2 months; then, four defects were grafted with rhPDGF-BB + ß-TCP + a wound healing dressing, and two defects received CTGs. A coronally advanced flap covered each grafted site. Nine months later, sections were obtained for examination. All four sites treated with rhPDGF-BB + ß-TCP showed connective tissue fibers (Sharpey fibers) perpendicularly inserting into newly formed cementum and alveolar bone. In the two sites treated with CTGs, a long junctional epithelium was seen coronal to the osseous crest and connective tissue fibers ran parallel to the adjacent root surfaces, with no evidence of insertion into cementum or bone. There was no evidence of regeneration of cementum, inserting connective tissue fibers, or supporting alveolar bone. Regeneration of the periodontium in gingival recession defects is possible through growth factor-mediated therapy.

A new therapeutic system using purified recombinant human platelet-derived growth factor-BB (rhPDGF-BB) in combination with a biocompatible, osteoconductive, synthetic scaffold beta-tricalcium phosphate (ß-TCP) has recently been shown in a large-scale, prospective, blinded, randomized clinical trial to safely and effectively treat advanced periodontal osseous defects. A significant gain in clinical attachment level was observed 3 months postsurgery for sites treated with 0.3 mg/mL rhPDGF-BB + ß-TCP versus ß- TCP + buffer (active control), with this trend continuing at 6 months postsurgery. Additionally, sites treated with 0.3 mg/mL rhPDGF-BB + ß-TCP also had significantly greater radiographic linear bone gain and percent defect fill at 6 months postsurgery than sites that received bone substitute with buffer. Representative cases from the clinical trial were followed to assess their ability to maintain the initial effect of treatment observed at 6 months. At 18 or 24 months postsurgery, with the same clinical and radiographic measurement techniques used as were performed at the 6-month time point for the clinical trial, these cases demonstrated maintenance of the clinical attachment level for all but one case, with all cases demonstrating substantial increases in linear bone gain and percent bone fill versus measurements obtained at 6 months postsurgery. Substantial radiographic changes in the appearance of the defect fill were observed for both rhPDGF-BB treatment groups, consisting of increased radiopacity and bone trabeculation, indicative of increased mineralization and maturation of the bone observed 6 months postsurgery.

When mixed with an osteoconductive scaffold, recombinant human plateletderived growth factor (rhPDGF-BB), a potent wound-healing protein, has been shown to promote clinical attachment gain, radiographic bone fill, and regeneration of the periodontium. This human case series evaluated the clinical outcome of rhPDGF with beta tricalcium phosphate (ß-TCP) and a collagen membrane in the treatment of recession-type defects. The control was the clinical gold standard for root coverage: the subepithelial connective tissue graft (CTG). Seven patients with recession defects >= 3 mm in contralateral quadrants of the maxilla, excluding molars, were treated in this series. Patients were followed postoperatively, and healing was evaluated at 8, 16, and 24 weeks, with recession depth as the primary outcome measure. This case series revealed a favorable tissue response to rhPDGF-BB + ß-TCP and a collagen membrane and comparable clinical outcomes to CTG, warranting a controlled clinical trial of greater magnitude.

The purpose of this study was to determine if patients prefer ultrasonic or hand instruments for periodontal maintenance. A questionnaire of 13 items was answered by 469 patients in three periodontal offices. The results showed a strong preference (74%) for ultrasonic instruments. The possibility of increased compliance because of this preference is discussed.