Pinwheel Pedicle Flap Technique for Increasing Keratinized Tissue at Stage 2 Implant Surgery.

INTRODUCTION: The goal of stage 2 implant surgery is to uncover implants while maintaining or augmenting the peri-implant keratinized tissue. Although the absolute requirement for keratinized tissue around natural teeth can be debated, implants appear to have consistently improved postoperative clinical parameters and health when there is an adequate keratinized peri-implant tissue. CASE PRESENTATION: This article presents a new technique to optimize the keratinized tissue around implants during stage 2 surgery. Although there are many treatment options that can be considered at the time of surgery, the technique presented here has the advantage of increasing the keratinized tissue circumferentially around the implant without using a second donor site. The technique, called the "pinwheel," is presented in two cases with the same clinical presentation. Two mandibular overdenture patients with ≤3 mm of keratinized tissue over implant sites, stage 2 surgery was performed using the "pinwheel technique" to increase the keratinized tissue on the facial and lingual surfaces. CONCLUSION: The use of the pinwheel technique to augment keratinized tissue around implants is effective and is a viable treatment option during stage 2 implant surgery.

Evaluation of the Sealing Capability of the Internal Conical Connections of Implants with Titanium and Zirconia Abutments.

AIM: The purpose of this in vitro investigation was to evaluate the sealing capability of the conical implant-abutment interfaces under different abutment screw torque values using titanium and zirconia abutments with Morse taper designs. MATERIALS AND METHODS: A total of 42 dental implants (n = 21 for titanium abutments and n = 21 for zirconia abutments) were inoculated internally with three bacteria. These assemblies were divided into four test groups (n = 10) based on screw fixation torques of 35 or 20 Ncm and placed in sterile broth; the remaining abutments were used as positive controls and torqued to 10 Ncm. Microleakage was quantified by enumerating the bacteria from the colony-forming units. An analysis of variance for the estimates of bacteria enumerated and microgaps was used with a post hoc analysis as indicated. A p-value of 0.05 was used as the level of significance. RESULTS: There was no statistically significant difference in microleakage among the four test groups; there were no significant effects of screw torque or abutment type on the bacteria enumerated. There was a significantly smaller mean microgap with the zirconia abutments. CONCLUSION: The results of this study indicated no statistically significant difference in the sealing capabilities between titanium and zirconia abutments, having internal conical connections, after increasing the abutment screw torque. CLINICAL SIGNIFICANCE: It is important for clinicians to follow the guidelines suggested by the implant companies to avoid biomechanical complications over time.

The rate of adverse events during IV conscious sedation.

Conscious sedation has become an integral part of dentistry; it is often used to reduce anxiety or fear in some patients during oral surgery, periodontal surgery, implant placement, and general dentistry procedures. The purpose of this study was to evaluate the frequency of adverse events during IV conscious sedation provided by credentialed general dentists and periodontists in the United States Air Force (USAF). Sedation clinical records (Air Force Form 1417) from calendar year 2009 were requested from all USAF bases. A total of 1,468 records were reviewed and 19 adverse events were noted in 17 patients. IV complication (infiltration) was the most common adverse event. The overall adverse event rate was 1.3 per 100 patients treated. The results of this study show that moderate sedation provided by general dentists and periodontists in the USAF has a low incidence of adverse events, and conscious sedation remains a viable option for providers for the reduction of anxiety in select patients.

Effect of repeated refrigerant spray applications using various carriers on pulpal temperature change.

This study sought to determine how repeated applications of a refrigerant spray on various cotton carriers affected the change in pulpal temperature. A thermocouple was placed at the roof of the pulp chamber of a human maxillary canine and connected to a thermometer logging at one-second intervals while the root was immersed in a water bath at 37 degrees C. Four different carrier types were used: large cotton pellets, small cotton pellets, cotton-tip applicators, and cotton rolls. Each carrier was sprayed with 1,1,1,2-tetrafluoroethane and placed on the crown for five seconds. Pulpal temperature change was recorded after each five second application of the same carrier to the tooth until a total of six consecutive sprays and applications of the carrier were applied. Each carrier group consisted of 10 performances of the six sets of readings (n = 10). The difference between baseline and the low temperature reading was calculated to determine the temperature change (in degrees C) in the pulp chamber per application. When the refrigerant spray was used, the large cotton pellet carrier generally produced the largest decrease in pulpal temperature at each repeated application compared to the other types of carriers. However, the same large cotton pellet should not be sprayed with the refrigerant more than two times before it is replaced.

Retrospective analysis of dental implants among United States Air Force basic military trainees.

OBJECTIVE: To determine the prevalence of dental implants among the Air Force basic military trainees and to radiographically identify the type of dental implant systems. METHODS: All digital panoramic radiographic images acquired from Oct 1, 2006 through July 31, 2007 of newly recruited Air Force trainees were evaluated for evidence of dental implants. The following data were collected: total number of implants per radiograph, gender and age of subjects, implant location, type of implant retention method, and restorative implant status. The implants identified were categorized as Nobel Biocare/3i type or non-Nobel Biocare/3i type. RESULTS: A total of 47 radiographs were identified with 63 dental implants being detected out of 26,293 panoramic radiographs surveyed. Of the 63 identified dental implants, 34 were Nobel Biocare/3i type and 29 were non-Nobel Biocare/3i type. CONCLUSIONS: The prevalence of dental implants among Air Force basic military trainees was 0.24% with 54% of the implants being identified as Nobel Biocare/3i type.

Human periodontal fibroblast response to enamel matrix derivative, amelogenin, and platelet-derived growth factor-BB.

BACKGROUND: The ideal goal of clinical therapy in periodontal defects is regeneration of all lost structures. For regeneration to occur, cell proliferation, migration, and extracellular matrix synthesis are prerequisites. Attempts at regeneration of periodontal defects by guided tissue regeneration using bone grafts and membranes have not always yielded predictable results. Recently, attempts at engineering the defects using various materials have shown promising results. Two such approaches have been used to regenerate periodontal defects, one using extracellular matrix such as enamel matrix proteins and the other using growth factors. However, to our knowledge, no study has looked at combining these two approaches to achieve potentially even greater regeneration. METHODS: Primary human periodontal ligament (PDL) fibroblasts were explanted, and alkaline phosphatase (ALK PHOS) activity was determined. Phenotypically different cell lines were incubated for 1, 3, 6, and 10 days in 0.2% fetal bovine serum (FBS) media containing different concentrations of either enamel matrix derivative (EMD), amelogenin, platelet-derived growth factor-BB (PDGF-BB), EMD+PDGF-BB, or amelogenin+PDGF-BB. A culture of 0.2% FBS alone served as a negative control, and a culture of 10% FBS served as a positive control. Cell proliferation was measured using a Coulter counter to determine the cell number. The effects on a wound-fill model were evaluated by scraping a 3-mm wide cell-free zone in PDL monolayers across the diameter of the tissue-culture plate and determining PDL cell migration into the cell-free zone using computer assisted histomorphometry. RESULTS: Compared to the control, only EMD+PDGF-BB significantly increased PDL cell proliferation in an ALK PHOS (-) cell line (P<0.001), and EMD alone, EMD+PDGF-BB, and amelogenin+PDGF-BB significantly increased PDL cell proliferation in an ALK PHOS (+) cell line (P<0.001) with EMD+PDGF-BB showing a trend for greater proliferation than either PDGF or EMD alone. Individually, EMD and amelogenin had no significant effect on PDL cell proliferation. In the wound-fill experiment, all factors and their combinations except amelogenin significantly enhanced cell migration compared to the control (P<0.05) at the wound edge. In addition, EMD+PDGF-BB had additive effects on the ALK PHOS (-) cell line at the wound edge. At the center of the wound, neither EMD nor amelogenin had a significant wound-fill effect. However, the combination of EMD+PDGF-BB additively increased wound fill for both ALK PHOS (+) and ALK PHOS (-) cells. CONCLUSIONS: The combination of EMD and PDGF-BB produces greater proliferative and wound-fill effects on PDL cells than each by themselves. If these combined effects can be translated clinically, one may see greater regeneration in periodontal defects with this combination. However, amelogenin does not have significant effects on PDL cell proliferation or migration by itself. This may suggest that either another enamel matrix component in EMD may be responsible for some of its clinical effects, or that amelogenin alone may not trigger the regenerative potential of periodontal tissues and that it requires a combined interaction with other enamel matrix components of EMD to direct the regenerative process.