Clinical evaluation of Er,Cr:YSGG laser therapy used as an adjunct to non-surgical treatment of periodontitis: Twelve-month results from a pilot study.

BACKGROUND: The purpose of this study was to evaluate the results of adjunctive Er,Cr:YSGG laser therapy with scaling and root planing (SRP) as compared with SRP alone in the treatment of moderate to severe periodontitis. METHODS: Fifteen adults (aged 27 to 65 years) with 90 nonadjacent sites probing ≥ 5 mm were treated in split-mouth design with SRP and laser therapy versus SRP alone. Probing pocket depth (PPD), gingival recession (GR), clinical attachment level (CAL), plaque, and bleeding on probing were collected at baseline, 1, 3, 6, 9, and 12 months. Patient reported outcomes were measured to assess pain, sensitivity, and satisfaction. RESULTS: Clinical improvements were similar for test and control sites with no statistically significant difference. At 12 months, the average PPD reduced from 6.1 to 4.2 mm for test and 6.2 to 4.3 mm for control sites. GR increased by 0.4 mm at test and control sites. CAL increased from 6.8 to 5.3 mm for test and 6.9 to 5.5 mm for control sites. Clinical outcomes were stratified by baseline PPD ( = 5, = 6 and ≥7 mm) and analyzed for number of sites that reduced (≤4 mm). No significant difference was observed when the baseline PPD was 5 or 6 mm. Test sites with baseline PPD ≥7 mm demonstrated a statistically significant difference in the percentage of reduced sites when compared with controls at nine (P = 0.001) and 12 months (P = 0.044). CONCLUSIONS: Adjunctive Er,Cr:YSGG laser therapy with SRP provides similar clinical improvement in the treatment of moderate-severe periodontitis as SRP alone and may offer some advantage for deeper (≥7 mm) pockets.

Enamel Matrix Derivative in Diffusion Chamber Implanted Subcutaneously in Rat Induces Formation of Fibrous Connective Tissue Containing Abundant Blood Vessels.

BACKGROUND: Enamel matrix derivative (EMD) is widely used for regeneration therapy in dental clinical situations, but the mechanism of EMD bioactivity remains obscure. To clarify this mechanism, we focused on the formation of connective tissue and blood vessels. The aim of this study was to confirm whether EMD induces the formation of connective tissue and blood vessels by using the diffusion chamber (DC) technique. MATERIALS AND METHODS: Individual DCs containing EMD (DC-EMD) or propylene glycol alginate (PGA) were implanted subcutaneously in rat dorsum. At 4 weeks after the implantation, histological analysis of DCs was performed using azan staining. RESULTS: DC-EMD induced the formation of much larger amounts of connective tissue containing abundant blood vessels than did DC-PGA. CONCLUSION: The results indicated that EMD can induce the formation of both connective tissue and blood vessels. This bioactivity may contribute to the mechanism whereby EMD induces tissue regeneration.

Photodynamic Therapy with Pyoktanin Blue and Diode Laser for Elimination of Enterococcus faecalis.

BACKGROUND/AIM: Enterococcus faecalis is responsible for most cases of endodontic treatment failure. Despite various conventional disinfection methods, root canals are not completely free of microorganisms. Photodynamic therapy (PDT) is a new antimicrobial strategy that involves the use of a non-toxic photosensitizer (PS) and a light source. The aim of this study was to evaluate the antimicrobial effect of PDT using diode laser and pyoktanin blue (PB) and confirm the nontoxicity of PB as a PS. MATERIALS AND METHODS: Laser irradiation with an output power of 3 W was performed with PB as the PS to a bacterial solution containing E. faecalis. Then, the number of colony-forming units was counted. PB cytotoxicity was also assessed by the MTT assay. RESULTS: E. faecalis counts were reduced after laser irradiation, laser irradiation with PB, or the combination thereof compared to the control, non-irradiation or water. The 50% cytotoxic concentration value for adult human dermal fibroblasts incubated with PB for 1 min was 108 µg/ml. CONCLUSION: Diode laser irradiation in combination with PB as the PS is efficacious for the elimination of E. faecalis without toxic effects to human dermal fibroblasts. This strategy might be useful for root canal irrigants.

Salivary exRNA biomarkers to detect gingivitis and monitor disease regression.

AIM: This study tests the hypothesis that salivary extracellular RNA (exRNA) biomarkers can be developed for gingivitis detection and monitoring disease regression. MATERIALS AND METHODS: Salivary exRNA biomarker candidates were developed from a total of 100 gingivitis and non-gingivitis individuals using Affymetrix's expression microarrays. The top 10 differentially expressed exRNAs were tested in a clinical cohort to determine whether the discovered salivary exRNA markers for gingivitis were associated with clinical gingivitis and disease regression. For this purpose, unstimulated saliva was collected from 30 randomly selected gingivitis subjects, the gingival and plaque indexes scores were taken at baseline, 3 and 6 weeks and salivary exRNAs were assayed by means of reverse transcription quantitative polymerase chain reaction. RESULTS: Eight salivary exRNA biomarkers developed for gingivitis were statistically significantly changed over time, consistent with disease regression. A panel of four salivary exRNAs [SPRR1A, lnc-TET3-2:1, FAM25A, CRCT1] can detect gingivitis with a clinical performance of 0.91 area under the curve, with 71% sensitivity and 100% specificity. CONCLUSIONS: The clinical values of the developed salivary exRNA biomarkers are associated with gingivitis regression. They offer strong potential to be advanced for definitive validation and clinical laboratory development test.

Effects of surface microtopography of titanium disks on cell proliferation and differentiation of osteoblast-like cells isolated from rat calvariae.

The surface topography of implant fixture is an important factor affecting the osseointegration. We herein demonstrated the effects of surface microtopography of titanium disks on proliferation and differentiation of osteoblast-like cells isolated from rat calvariae. Titanium disks with machine surface (MS), rough surface (R1) and rough surface combined with small cavities (R2) were used in an in vitro culture system. Rough surfaces (R1 and R2 disks) induced stronger osteoblast proliferation and differentiation (BGP and sclerostin mRNA expressions and calcium content) than the smooth surface (MS disk). Furthermore, surface microtopography of R2 disk, which was rough with small cavities, more strongly induced cell proliferation and mineralized bone matrix production than R1 disk. Our results suggest that surface microtopography influences osteoblast proliferation and differentiation. R2 disk, which is rough with small cavities, may be used in implant fixtures to increase osseointegration.

The Modified Apically Repositioned Flap Technique: A Long-Term (4 to 16 Years) Retrospective Study.

Attached gingiva is desirable for the maintenance of gingival health. Although many methods are used to increase the zone of attached gingiva, the modified apically repositioned flap (MARF) technique has the advantages of simplicity and predictability. The short-term follow-up of the MARF technique demonstrated an increase in keratinized tissue and attached gingiva. This study evaluated long-term results of the MARF technique as used to increase the apicocoronal dimensions of keratinized tissue and attached gingiva in 28 sites (25 patients; average follow-up of 9 years). There was a statistically significant increase in keratinized tissue and attached gingiva with no increase in probing depths or gingival recession. These results suggest that the MARF procedure predictably generates keratinized tissue and attached gingiva with long-term stability.

Use of the Modified Apically Repositioned Flap Technique to Create Attached Gingiva in Areas of No Keratinized Tissue: A Clinical and Histologic Evaluation.

The complete absence of keratinized attached gingiva on the buccal surface of a tooth can make the area more susceptible to gingival recession. The modified apically repositioned flap (MARF) technique is an effective procedure to increase the dimensions of attached gingiva in areas that present with some existing keratinized tissue. The objective of this case report is to present long-term clinical and histologic evidence that the MARF technique can be used to create attached gingiva in areas that lack keratinized tissue.

Papilla Reformation at Single-Tooth Implant Sites Adjacent to Teeth with Severely Compromised Periodontal Support.

Reformation of the lost interdental papilla remains one of the most challenging goals for clinicians. When a single tooth is replaced with an implant, the papilla between the tooth and the implant can often be maintained or predictably reformed as long as the adjacent tooth's periodontal attachment and bone are preserved. However, if the periodontal support is compromised on the neighboring natural tooth, the papilla will often be deficient or missing. The cases presented herein demonstrate long-term follow-up of successful reformation of periodontal/peri-implant tissue contours, including reconstruction of lost interproximal bone and papilla at periodontally compromised sites using a combined hard and soft tissue surgical approach.

The effect of implant macro-thread design on implant stability in the early post-operative period: a randomized, controlled pilot study.

INTRODUCTION: Available literature suggests there is a transient drop in implant stability from approximately week 0 to week 3-4 as a result of peri-implant bone remodeling as it transitions from a primary, mechanical stability to a secondary, biological stability. Research investigating the influence of macro-thread design on this process is scant. AIM: The specific aim of this study was to evaluate the role of macro-thread design on implant stability in the early post-operative healing period using resonance frequency analysis (RFA). MATERIAL AND METHODS: Seven patients, each missing at least two posterior teeth in the same arch, were included in the study. Three patients qualified for four implants resulting in a total of 10 matched pairs. All sites were healed (>6 months), non-grafted sites with sufficient bone to place implants. Each site in a matched pair was randomly assigned to receive either a control (Megagen EZ Plus Internal; EZ) or test (Megagen AnyRidge; AR) implant. The test implant incorporates a novel thread design with a wide thread depth and increased thread pitch. RFA was used to determine implant stability quotient (ISQ) values for each implant at the time of placement and weekly for the first 8 weeks. RESULTS: Implants consistently achieved a relatively high insertion torque (30-45 N/cm) and high initial ISQ value (79.8 ± 1.49). Baseline ISQ values for test (AR; 79.55 ± 1.61) and control (EZ; 80.05 ± 1.37) implants were similar. A general pattern of stability from baseline through all eight follow-up evaluations was observed for the test implants. A pattern of decreasing ISQ values was observed for the control implants across the early follow-up evaluations up to week four, where the value plateaued. There was a statistically significant main effect due to implant type (P < 0.01) and a statistically significant interaction between implant type and time (P < 0.01), indicating that the test and control implants performed differently at certain time points. CONCLUSIONS: Within the limitations of this study, macro-thread design appears to play a role in implant stability in the early post-operative healing period as assessed by RFA. These findings may have important implications related to immediate or early loading protocols.

Abutment-Supported Papilla: A Combined Surgical and Prosthetic Approach to Papilla Reformation.

Restoration of lost interdental papilla remains one of the most challenging goals for clinicians. When a single tooth is replaced with an implant, the papilla between the tooth and the implant can often be maintained or predictably reconstructed as long as the periodontal attachment and bone of the adjacent tooth is preserved. However, if the periodontal support is compromised on the neighboring natural tooth, the papilla will often be deficient or missing. This article presents a multidisciplinary treatment approach to regenerate the interdental papilla between an implant and a periodontally compromised tooth using surgical procedures and a customized abutment. Specifically, an abutment with modified subgingival contours is used to enhance support of the surgically reformed papilla.

Periodontal regeneration - furcation defects: a consensus report from the AAP Regeneration Workshop.

BACKGROUND: Treatment of furcation defects is a core component of periodontal therapy. The goal of this consensus report is to critically appraise the evidence and to subsequently present interpretive conclusions regarding the effectiveness of regenerative therapy for the treatment of furcation defects and recommendations for future research in this area. METHODS: A systematic review was conducted before the consensus meeting. This review aims to evaluate and present the available evidence regarding the effectiveness of different regenerative approaches for the treatment of furcation defects in specific clinical scenarios compared with conventional surgical therapy. During the meeting, the outcomes of the systematic review, as well as other pertinent sources of evidence, were discussed by a committee of nine members. The consensus group members submitted additional material for consideration by the group in advance and at the time of the meeting. The group agreed on a comprehensive summary of the evidence and also formulated recommendations for the treatment of furcation defects via regenerative therapies and the conduction of future studies. RESULTS: Histologic proof of periodontal regeneration after the application of a combined regenerative therapy for the treatment of maxillary facial, mesial, distal, and mandibular facial or lingual Class II furcation defects has been demonstrated in several studies. Evidence of histologic periodontal regeneration in mandibular Class III defects is limited to one case report. Favorable outcomes after regenerative therapy for maxillary Class III furcation defects are limited to clinical case reports. In Class I furcation defects, regenerative therapy may be beneficial in certain clinical scenarios, although generally Class I furcation defects may be treated predictably with non-regenerative therapies. There is a paucity of data regarding quantifiable patient-reported outcomes after surgical treatment of furcation defects. CONCLUSIONS: Based on the available evidence, it was concluded that regenerative therapy is a viable option to achieve predictable outcomes for the treatment of furcation defects in certain clinical scenarios. Future research should test the efficacy of novel regenerative approaches that have the potential to enhance the effectiveness of therapy in clinical scenarios associated historically with less predictable outcomes. Additionally, future studies should place emphasis on histologic demonstration of periodontal regeneration in humans and also include validated patient-reported outcomes. CLINICAL RECOMMENDATIONS: Based on the prevailing evidence, the following clinical recommendations could be offered. 1) Periodontal regeneration has been established as a viable therapeutic option for the treatment of various furcation defects, among which Class II defects represent a highly predictable scenario. Hence, regenerative periodontal therapy should be considered before resective therapy or extraction; 2) The application of a combined therapeutic approach (i.e., barrier, bone replacement graft with or without biologics) appears to offer an advantage over monotherapeutic algorithms; 3) To achieve predictable regenerative outcomes in the treatment of furcation defects, adverse systemic and local factors should be evaluated and controlled when possible; 4) Stringent postoperative care and subsequent supportive periodontal therapy are essential to achieve sustainable long-term regenerative outcomes.

Periodontal Regeneration - Furcation Defects: Practical Applications From the AAP Regeneration Workshop.

Focused Clinical Question: How should periodontal furcation defects be managed via periodontal regenerative therapy, and what parameters should be used for treatment selection? Summary: The treatment of furcation defects can vary based on the type and location of the furcation involvement. Attaining predictable regenerative outcomes is dependent on the control of local and systemic factors. A combined treatment approach (barrier and bone replacement graft with or without biologic) generally offers the better therapeutic outcome over monotherapy. Class I furcation defects can be managed via conventional periodontal non-surgical and/or surgical therapy, whereas Class II furcation defects generally attain better outcomes with regenerative therapy. There is weak evidence, limited to case reports, that Class III furcation defects can be treated successfully with regenerative therapy. Conclusions: In Class I furcation defects, regenerative therapy might be beneficial in certain clinical scenarios, although most Class I furcation defects can be treated successfully with non-regenerative therapy. For successful treatment of maxillary and mandibular molars with Class II furcation defects, systemic and local factors should be controlled, and surgical debridement and postoperative maintenance should be performed adequately. Although there is limited evidence for regeneration of Class III furcation defects, there may be a modest improvement allowing for tooth retention. Ultimately, the benefit of tooth retention and cost should be considered in the indication of therapy for teeth with severe furcation involvement.

Effect of Implant Diameter and Ridge Dimension on Stress Distribution in Mandibular First Molar Sites-A Photoelastic Study.

The long-term clinical success of a dental implant is dependent upon maintaining sufficient osseointegration to resist forces of occlusion. The purpose of this study was to investigate the effect of implant diameter on stress distribution around screw-type dental implants in mandibular first molar sites using photoelastic models. The design included models with different buccal-lingual dimension. Twelve composite photoelastic models were assembled using 2 different resins to simulate trabecular and cortical bone. Half of the models were fabricated with average dimensions for ridge width and the other half with narrower buccal-lingual dimensions. One internal connection implant (13 mm length) with either a standard (4 mm), wide (5 mm), or narrow (3.3 mm) diameter was embedded in the first molar position of each photoelastic model. Half the implants were tapered and the other half were straight. Full gold crowns in the shape of a mandibular first molar were fabricated and attached to the implants. Vertical and angled loads of 15 and 30 pounds were applied to specific points on the crown. Wide-diameter implants produced the least stress in all ridges while narrow-diameter implants generated the highest stress, especially in narrow ridges. It may be that the volume and quality of bone surrounding implants influences stress distribution with a greater ratio of cortical to trabecular bone, thus providing better support. Models with wide-diameter implants loaded axially had a more symmetrical stress distribution compared to standard and narrow diameter implants. A more asymmetrical stress pattern developed along the entire implant length with angled loads. Implant diameter and ridge width had considerable influence on stress distribution. Narrow-diameter implants produced more stress than wide diameter implants in all conditions tested.

Cone Beam Computed Tomography for the Dental Implant Patient.

Cone beam computed tomography offers many advantages over 2-D imaging for the evaluation of potential implant sites. With the use of CBCT scans becoming more commonplace, it is important for clinicians to be knowledgeable and to use this new technology appropriately and judiciously. The purpose of this article is to describe the advantages and limitations of CBCT imaging for the presurgical and postsurgical evaluations of implant treatment and assessment of implant-related complications.

Screw-access marking: a technique to simplify retrieval of cement-retained implant prostheses.

One of the commonly cited disadvantages of cement-retained implant prostheses is their inability to be retrievable. The screw-access marking technique discussed in this article allows for any clinician, at any time, to simply and predictably retrieve the cemented implant prosthesis. By applying a discrete, but easily recognizable, marking on the occlusal surface of the restoration, the entry point into the screw-access chamber can be precisely and safely created. The screw-access marking technique is efficient, effective, and widely applicable.

Immediate implant-supported provisional restoration with a root-form pontic for the replacement of two adjacent anterior maxillary teeth: A clinical report.

In implant therapy, the replacement of 2 adjacent maxillary anterior teeth presents several unique challenges: mesiodistal space constraints, the need to maintain or create natural gingival esthetics, the need for esthetic provisional restorations, and the management of nonaxial forces. The treatment presented addresses these challenges through the use of an immediately placed single implant at the central incisor position with a central to lateral incisor cantilever prosthesis in both the immediate provisional and definitive restorations. The provisional restoration was designed to minimize pressure on the surgical site, optimize space for the gingival tissues, and control occlusal loading of the implant during the initial stages of osseointegration. The pontic was modified to replicate the subgingival root anatomy and enhance the gingival esthetic outcome.

Abutment emergence modification for immediate implant provisional restorations.

UNLABELLED: In their stock form, some titanium provisional implant abutments are not ideally designed for use in immediate placement/immediate provisional restoration treatment. This is largely due to the apical flare design that applies excessive pressure to the peri-implant soft tissue complex and crestal bone. This appears to have the undesirable effect of increasing peri-implant bone resorption and severely impeding the potential for increases in gingival volume. This type of stock titanium abutment will therefore benefit significantly from recontouring. The subgingival portion of the abutment is recontoured from the flared stock shape to a straight or parallel design. This modification minimizes pressure on the surgical site and provides additional space around the subgingival portion of the provisional restoration, within which the gingiva has the potential to remodel and fill. This allows the potential formation of additional peri-implant gingival volume and a coronal maintenance or migration of the soft tissue complex. In order to minimize the "graying effect" of titanium abutments, the retentive portion is opaqued by the technician or clinician. These modifications will improve the potential outcomes for both the peri-implant gingiva and the provisional restoration. CLINICAL SIGNIFICANCE: Narrowing the emergence profile of implant abutments for use in immediate implant provisional restorations appears to allow for creation of greater peri-implant volume. Thus resulting in increased esthetic potential and predictability of the peri-implant gingiva.

A high-throughput comparative characterization of laser-induced soft tissue damage using 3D digital microscopy.

3D digital microscopy was used to develop a rapid alternative approach to quantify the effects of specific laser parameters on soft tissue ablation and charring in vitro without the use of conventional tissue processing techniques. Two diode lasers operating at 810 and 980 nm wavelengths were used to ablate three tissue types (bovine liver, turkey breast, and bovine muscle) at varying laser power (0.3, 1.0, and 2.0 W) and velocities (1-50 mm/s). Spectrophotometric analyses were performed on each tissue to determine tissue-specific absorption coefficients and were considered in creating wavelength-dependent energy attenuation models to evaluate minimum heat of tissue ablations. 3D surface contour profiles characterizing tissue damage revealed that ablation depth and tissue charring increased with laser power and decreased with lateral velocity independent of wavelength and tissue type. While bovine liver ablation and charring were statistically higher at 810 than 980 nm (p < 0.05), turkey breast and bovine muscle ablated and charred more at 980 than 810 nm (p < 0.05). Spectrophotometric analysis revealed that bovine liver tissue had a greater tissue-specific absorption coefficient at 810 than 980 nm, while turkey breast and bovine muscle had a larger absorption coefficient at 980 nm (p < 0.05). This rapid 3D microscopic analysis of robot-driven laser ablation yielded highly reproducible data that supported well-defined trends related to laser-tissue interactions and enabled high throughput characterization of many laser-tissue permutations. Since 3D microscopy quantifies entire lesions without altering the tissue specimens, conventional and immunohistologic techniques can be used, if desired, to further interrogate specific sections of the digitized lesions.

Optical protein sensor for detecting cancer markers in saliva.

A surface immobilized optical protein sensor has been utilized to detect Interleukin-8 (IL-8) protein, an oral cancer marker, and can reach limit of detection (LOD) at 1.1 pM in buffer without using enzymatic amplification. Only after applying enzymatic amplification to increase the signal level by a few orders of magnitude, ELISA can reach the LOD of 1 pM level. We then develop the confocal optics based sensor for further reducing the optical noise and can extend the LOD of the surface immobilized optical protein sensor two orders in magnitude. These improvements have allowed us to detect IL-8 protein at 4.0 fM in buffer. In addition, these sensitive LODs were achieved without the use of enzymatic signal amplification, such that the simplified protocol can further facilitate the development of point-of-care devices. The ultra sensitive optical protein sensor presented in this paper has a wide number of applications in disease diagnoses. Measurements for detecting biomarkers in clinical sample are much more challenging than the measurements in buffer, due to high background noise contributed by large collections of non-target molecules. We used clinical saliva samples to validate the functionality of the optical protein sensor. Clinical detection of disease-specific biomarkers in saliva offers a non-invasive, alternative approach to using blood or urine. Currently, the main challenge of using saliva as a diagnostic fluid is its inherently low concentration of biomarkers. We compare the measurements of 40 saliva samples; half from oral cancer patients and half from a control group. The data measured by the optical protein sensor is compared with the traditional Enzyme-Linked Immunosorbant Assay (ELISA) values to validate the accuracy of our system. These positive results enable us to proceed to using confocal optical protein sensor to detect other biomarkers, which have much lower concentrations.