Strontium-loaded hydrogel scaffolds to promote gingival fibroblast function.

Dental implant clinical success is dependent on effective peri-implant tissue attachment to the trans-mucosal portion following placement. Modification of transmucosal implant surfaces can improve cellular adhesion and function leading to formation of an effective soft-tissue seal during healing, of which gingival fibroblasts are prominent cells to migrate to repair wounds and crucial for the development of a collagen rich connective tissue. Biocompatible loaded scaffold materials have been developed to allow local release of molecules with effective biological activity. Our previous studies indicate that strontium can promote gingival fibroblast metabolism, decrease apoptosis and support adhesion to titanium healing abutments. In this study, we developed a strontium-loaded alginate hydrogel scaffold which can be easily personalized to fit over any size and shape of implant transmucosal collar or healing abutment. Results indicate that biologically active strontium ions are effectively released from loaded alginate hydrogel material to promote fibroblast viability and migration to repair in vitro wounds similar to that of strontium citrate solution. Overall, this novel strontium-loaded alginate scaffold device displays good biocompatibility and functionality, demonstrating high potential as a system to provide local delivery of strontium to improve peri-implant mucosal healing following implant placement and clinical success.

Should the Quality of Glycemic Control Guide Dental Implant Therapy in Patients with Diabetes? Focus on Implant Survival.

INTRODUCTION: Optimal glycemic control is crucial to dental implant long-term functional and esthetic success. Despite HbA1c levels of 7% or lower used is as an indicator for good glycemic control, however, this level may not be attainable for all diabetic patients. Most dentists do not consider patients with poor glycemic control candidates for implant therapy due to higher implant failure, infection or other complications. AIM: This review challenges the concept of one size fits all and aims to critically appraise the evidence for the success or failure rate of dental implants and peri-implant health outcomes in patients with less than optimal glycemic control. DISCUSSION: Evidence suggests that estimating glycemic control from HbA1c measurement alone is misleading. Moreover, elevated preoperative HbA1c was not associated with increased mortality and morbidity after major surgical procedures. Literature for the survival or success of implants in diabetic patients is inconsistent due to a lack of standardized reporting of clinical data collection and outcomes. While a number of studies report that implant treatment in patients with well controlled diabetes has a similar success rate to healthy individuals, other studies suggest that the quality of glycemic control in diabetic patients does not make a difference in the implant failure rate or marginal bone loss. This discrepancy could indicate that risk factors other than hyperglycemia may contribute to the survival of implants in diabetic patients. CONCLUSION: In the era of personalized medicine, the clinician should utilize individualized information and analyze all risk factors to provide the patient with evidence-based treatment options.

Evaluation of clinical performance and survival rate of Straumann dental implants in Saudi Population based on cross-sectional study.

Risk indicators of peri-implantitis is still contradictory and somehow unclear in present literature therefore efforts should be done for better understanding of the exact etiology of peri-implant disease progression. The present study aimed to assess risk indicators associated with peri-implantitis by observing the changes in several periodontal parameters after implant placement. This cross-sectional study included 213 female and 271 male patients aged 26-87 years, who received 484 titanium implants (Straumann, Switzerland) at King Saud University's Dental College, Saudi Arabia. Patients were called for dental visits. During these visits; full clinical and radiographic assessment of implants were done. The periodontal pocket depth (PPD) was greater around implants placed at grafted sites than non-grafted sites and around bone-level implants than tissue-level implants. The plaque index (PI) was associated with poor oral hygiene. There was a strong association between graft (yes/no) and bleeding on probing (BOP). Patients with good oral hygiene showed high radiographic bone stability. Keratinized tissue width < 2 mm was associated with a higher PPD, higher PI, higher BOP, more edematous gingiva, and more exposed implant threads on radiography. In patients receiving implants, poor oral hygiene status and inadequate keratinized tissue level can be proposed as risk indicators for developing periimplantitis due to strong association found between them and developments of peri-implantitis.

Should Quality of Glycemic Control Guide Dental Implant Therapy in Patients with Diabetes? Focus on: Peri-Implant Diseases.

BACKGROUND AND AIM: Traditionally patients with metabolic conditions such as diabetes mellitus are considered not suitable candidates for dental implant therapy due to increased risk of infection, impaired bone healing or the potential for vascular complications. Peri-implantitis as the more progressive form of peri-implant disease involves bone loss and estimated to occur in nearly half of all implant cases long-term. Despite extensive research on association of hyperglycemia with dental implants in preclinical and animal models, translational effort to clinical practice is hampered by discrepancies in reported outcome indicators for peri-implantitis in patients with a spectrum of glycemic profiles. This review aims to evaluate clinical evidence for peri-implant disease in metabolically compromised patients and in particular in patients with poorly-controlled diabetes in order to inform clinical management of peri-implant disease. MATERIALS AND METHODS: A comprehensive literature review was performed utilizing PubMed database and using the key word 'diabetes' combined with "dental implant" or "Periimplantitis" or/and "Preimplant disease". RESULTS: Clinical studies with follow up more than 1year, systematic review and meta-analysis that evaluated peri-implant disease in diabetic patients in relation to glycemic control were taken into consideration in this review. CONCLUSION: Studies reported conflicting results regarding the long-term effect of diabetes on peri-implant health regardless of the level glycemic control. Therefore, interpretation of finding and relevance to clinical practise should be considered on individual bases.

Osteonecrosis of Jaws in Prostate Cancer Patients Treated With Antiresorptive Drugs: A Review.

Prostate cancer is the most frequently diagnosed cancer among elderly men in the United States. Skeletal architecture is affected by metastasis and androgen deprivation therapy (ADT), which is considered a gold standard treatment in prostate cancer. Osteoporosis and skeletal effects are reported among most patients on ADT. To counter these effects and to reduce bone turnover, antiresorptive drugs such as bisphosphonates and denosumab are commonly prescribed in prostate cancer. These drugs increase the prevalence of osteonecrosis of the jaw in a subset of patients. The future should hold promise for new drugs that could have a positive impact on bone metabolism without jeopardizing bone integrity.

Additive 3-dimensional printing as a novel tool for pre- and postsurgical evaluation and patient education: A clinical case series.

BACKGROUND AND OVERVIEW: In contrast to subtractive 3-dimensional (3D) techniques synonymous with computer-aided design and computer-aided manufacturing, rapid progress in additive 3D printing, especially fused filament fabrication or fused deposition modeling, can change the practice of dentistry. CASE DESCRIPTION: In this article, the authors outline the digital workflow for fused filament fabrication and fused deposition modeling 3D printing that involves converting a Digital Imaging and Communications in Medicine file (scan or radiograph) to a printable Standard Triangle Language file that can be modified (additions or manipulations) using a readily accessible software for 3D printing. The authors also present a clinical case series showing various applications for this technique, including clinician and patient education, treatment planning, and posttreatment evaluations. CONCLUSIONS AND PRACTICAL IMPLICATIONS: The low cost and simple workflow of additive 3D printing has potential to improve precision and efficiency in clinical dentistry for both academic and private practices.

Managing the Oral Health of Cancer Patients During the COVID-19 Pandemic: Perspective of a Dental Clinic in a Cancer Center.

The practice of dentistry has been dramatically altered by the coronavirus disease 2019 (COVID-19) pandemic. Given the close person-to-person contact involved in delivering dental care and treatment procedures that produce aerosols, dental healthcare professionals including dentists, dental assistants and dental hygienists are at high risk of exposure. As a dental clinic in a comprehensive cancer center, we have continued to safely provide medically necessary and urgent/emergent dental care to ensure that patients can adhere to their planned cancer treatment. This was accomplished through timely adaptation of clinical workflows and implementation of practice modification measures in compliance with state, national and federal guidelines to ensure that risk of transmission remained low and the health of both immunocompromised cancer patients and clinical staff remained protected. In this narrative review, we share our experience and measures that were implemented in our clinic to ensure that the oral health needs of cancer patients were met in a timely manner and in a safe environment. Given that the pandemic is still on-going, the impact of our modified oral healthcare delivery model in cancer patients warrants continued monitoring and assessment.

Effect of diode laser and topical fluoride applications on white-spot lesions in bovine enamel.

This study evaluated the effectiveness of diode laser irradiation combined with topical fluoride application for increasing the hardness of demineralized bovine enamel and esthetically improving white-spot lesions (WSLs). In addition, the study evaluated intrapulpal temperature changes during laser irradiation. One hundred twenty bovine incisors with 4 × 4-mm artificial WSLs were randomly assigned to 8 groups (n = 15): untreated control; fluoride only; LF1, LF2, and LF3, fluoride plus 2-W laser for 15, 30, and 60 seconds, respectively; and LF4, LF5, and LF6, fluoride plus 5-W laser for 15, 30, and 60 seconds, respectively. The Vickers hardness number, CIE L*a*b color space values, and visual analog scale ratings for color improvement were recorded at baseline, after demineralization to create the WSLs, and after treatment. The intrapulpal temperature changes were recorded at completion of irradiation for 30 bovine teeth that were assigned to 6 groups (n = 5) to receive doses of irradiation equivalent to the treatment of the corresponding laser groups described previously. Statistical analysis included 1-way analysis of variance and Tukey multiple comparison tests (α = 0.05) The mean Vickers hardness numbers were significantly greater for the laser groups, and mean visual analog scale scores were significantly greater for all the treatment groups (P < 0.05). The fluoride group had a significantly lower mean color change (ΔE*) value (P < 0.05). The mean intrapulpal temperature changes in the 5-W laser groups were significantly greater than those in the 2-W groups (P < 0.05). Diode laser irradiation combined with topical fluoride application significantly increased the hardness and improved the esthetic appearance of WSLs compared to no treatment (control) and fluoride treatment alone. Intrapulpal temperature changes indicated that diode laser irradiation is safer at a 2-W setting than a 5-W setting.

Strontium Effects on Human Gingival Fibroblasts.

Strontium is a naturally occurring alkaline earth metal that has been shown to be useful not only in the treatment and prevention of osteoporosis but also in the treatment of dentinal hypersensitivity in the oral cavity; strontium is also an effective cariostatic, antiplaque, antigingivitis agent. Relatively little is known, however, about the effects of strontium on gingival fibroblasts. The purpose of the present investigation was to conduct in vitro studies on the potential for strontium to positively affect the activity of these cells such that it might be effective in the enhancement of gingival attachment to surfaces, such as healing abutments in implants in the oral cavity. The results indicate that strontium added as strontium citrate (0.5-1.0 mM), both in the absence and presence of a healing abutment, increases human gingival cell activity and decreases apoptosis in these cells. Scanning electron microscopy studies also reveal that the addition of strontium increases attachment of gingival fibroblasts to the surfaces of healing abutments. These studies provide the basis for further investigations on the use of strontium in the prevention and treatment of peri-implantitis by maximizing the formation of a peri-implant soft-tissue barrier.

In vitro evaluation of controlled-release 14% doxycycline gel for decontamination of machined and sandblasted acid-etched implants.

BACKGROUND: Peri-implant infections are associated with the establishment and maturation of a bacterial biofilm characterized by a predominance of Gram-negative fusiform anaerobic species. The decontamination of implant surfaces is then crucial for a successful peri-implant therapy. METHODS: Twenty-one smooth and 21 rough implants, divided into four groups according to surface and treatment modality, were contaminated with Streptococcus sanguinis and then placed in an incubator with the atmosphere of 5% CO2 at 37°C for 24 hours to allow the bacteria to grow. After 24 hours, the test groups were treated with controlled release 14% doxycycline gel injecting the gel circumferentially over the surface of the implant for 3 minutes, while the control groups were irrigated with sterile saline for 1 minute. The implants were then vortexed into triptych soy broth to allow the bacteria to detach from the surface, diluted 1:100 and plated. Colony forming units (CFU) were counted 48 hours after incubation. RESULTS: The use of a 14% doxycycline gel minimized CFU counts compared to control groups, with the difference being statistically significant (P < 0.05). The reduction of CFUs in the smooth test group is more marked than in the rough test group, but the difference doesn't reach statistically significance (P = 0.215). CONCLUSIONS: The use of 14% doxycycline gel in implant surface decontamination was efficacious in this in-vitro study. Adjunctive use of locally delivered 14% doxycycline gel might be a viable option in the management of peri-implantitis and peri-implant mucositis considering its efficacy in reducing bacterial colonization.

Treatment of Peri-implantitis Using a Combined Decontaminative and Regenerative Protocol: Case Report.

Peri-implantitis is a long-term complication that frequently occurs after implant surgery. Several treatment methods have been proposed that are aimed at arresting the disease and potentially regenerating bone defects related to it. The use of a combination of proposed decontaminative treatments could possibly improve outcomes. In this case report the authors describe a combined mixed protocol, in which chemical decontamination and a laser-assisted decontamination technique are used in a surgical regenerative approach to successfully manage and treat a case of peri-implantitis. The combined surgical and antimicrobial protocol described can be a suitable treatment option in cases in which implants show severe bone resorption as a result of peri-implant disease.

Is Bone Graft or Guided Bone Regeneration Needed When Placing Immediate Dental Implants? A Systematic Review.

AIMS: To systematically review the effect and type of bone graft and guided bone regeneration around immediate implants on hard and soft tissue changes. METHODS: Three electronic databases were searched up to June 2015. Outcomes consisted of hard and soft tissue dimensional changes. RESULTS: Eight studies were included according to inclusion criteria. Immediate implants with bone grafting had superior soft tissue stability and preserved horizontal ridge dimension and buccal plate thickness, when compared to no grafting. The use of a barrier alone significantly decreased buccal plate resorption and the remaining defects around the implants, and the use of both bone graft and membrane aided in soft tissue preservation. The optimal type of bone graft material was a combination of cortical autogenous and synthetic particulate when compared to each separately, whereas no difference was found between demineralized allograft and hydroxyapatite in decreasing bone loss. CONCLUSIONS: Quantitative data analysis was not possible due to heterogeneity of the included studies. Further randomized clinical trials with homogenous samples and proper controls are needed to support the results of this report.

Effects of Two Diode Lasers With and Without Photosensitization on Contaminated Implant Surfaces: An Ex Vivo Study.

OBJECTIVE: The aim of this ex vivo study is to assess decontamination potential of two different diode laser wavelengths, with or without the aid of photodynamic therapy, on dental implant surfaces and to evaluate the harmful potential of temperature increase during laser irradiation. MATERIALS AND METHODS: One hundred thirty-two machined sterile implants were placed into sterile porcine bone blocks with standardized coronal angular bony defects and inoculated with Streptococcus sanguinis. Four different treatment protocols were used: 810 or 980 nm laser, with or without photosensitization. Two nontreated control groups were used, one with samples coated with indocyanine green dye. Samples were rinsed and plated on agar plates for subsequent colony count. Irradiation was repeated without contamination at room temperature and in a 37°C water bath monitoring the temperature variation. RESULTS: There is a statistically significant decontamination effect when the laser is used. Both wavelengths minimize contamination. There was modest improvement given by the photosensitization being more marked in the 810 nm groups, but was not statistically significant compared to laser only. A critical temperature increase was never observed when the sample was in a 37°C water bath. CONCLUSIONS: The use of both diode laser wavelengths in implant surface decontamination was efficacious regardless of the use of photosensitization and without dangerous increase of temperature.

A Combined Treatment for a Case of Peri-Implant Bisphosphonate-Related Osteonecrosis of the Jaw.

OBJECTIVE: Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is rarely reported as a complication after implants placement. In this article we report a combined treatment for a rare case of peri-implant BRONJ. METHODS: A 71-year-old female patient presented for follow-up of a 4.3 x 13 mm implant placed on first upper-left premolar position 3 years prior. She was complaining of soreness of the area and bleeding when brushing. The patient had a history of breast cancer (removed 7 years prior) for which she was taking anastrozole 1 mg/day, causing a decrease in mineral bone density as side effect, for which she was prescribed a side-therapy of oral risedronate 35 mg/week taken for 4 years and stopped 2 years prior. A 9 mm deep pocket was detected on the mesial-buccal aspect of the implant. At the first visit local minocycline microspheres delivery was performed as antibacterial and anti-inflammatory agent. The patient was seen 10 weeks later with the presence of a bone sequestrum on the mesial-palatal aspect of the implant. A surgical minimally invasive single-flap approach was done to minimize periosteal elevation. Decontamination with EDTA-gel followed by delivery of rh-PDGF (recombinant platelet derived growth factor) with ß-TCP (ß-tricalcium phosphate) stabilized with a CaSO4 barrier. A cycle of four consecutive 810 nm diode-laser-biostimulation visits was performed to promote fibroblasts growth. An 18-month post-surgical follow-up showed 3 mm residual probing depth (PD) and an absence of gingival inflammation with no symptoms reported by the patient. RESULTS: Antimicrobial, regenerative and biostimulation therapies were implemented to successfully treat BRONJ around an osseointegrated implant. The results showed noticeable PD reduction and radiographic bone regeneration after 18 months. CONCLUSIONS: A combined therapy aiming at regeneration of bone and soft tissues around osseointegrated implants was successful for treatment of implant-associated BRONJ.

Thermodynamic Effects of 3 Different Diode Lasers on an Implant-Bone Interface: An Ex-Vivo Study With Review of the Literature.

The aim of this study is to assess the increase of temperature following laser irradiation with 810 nm, 980 nm, and 1064 nm diode laser wavelengths, of an implant under conditions that more closely replicate those of the human body. A 4 × 14 mm machined surface implant was placed in a porcine rib to replicate the conductivity of heat given by the bone. A peri-implant vertical defect was made that was 2 mm wide and 2 mm deep to simulate bone resorption. Two thermocouples were positioned crestally and apically on the implant surface. The tip of the laser was kept 3 mm away from the surface and continuously moved in an up-and-down and side-to-side fashion, inside the defect for 60 seconds. Initial temperatures and the time needed to reach an increase of 10°C were recorded. The experiment was repeated at room temperature and in a 37°C water bath with the following settings: 0.6 W, 0.8 W, 1 W continuous and repeated in pulsed. A critical increase of temperature of more than 10°C is reached with all lasers at 0.8 W and 1 W in continuous mode at room temperature. Only the 1064 nm diode laser reached the critical increase at 0.8 W in pulsed mode. No critical increase of temperature was registered with other settings and when the bone block was placed in a 37°C water bath. The results of this study suggest that use of these diode lasers does not cause a harmful increase in temperature when used under conditions similar to those of the human body.

Promotion of cells to close gaps and encourage cell coverage, by radio frequency glow discharge treatment.

Exposure of dental abutments to cleaning and sterilizing Radio Frequency Glow Discharge Treatment (RFGDT) triggered greater degrees of human gingival fibroblast (HGF) attachment and spreading over their surfaces. Enhanced cell growth and metabolic activity of such HGFs were found which might lead to improved cellular margins in the smile-revealing "esthetic zone". This investigation, approved by the Institutional Review Board, employed in vitro studies of HGFs to support in vivo clinical applications of differentially treated titanium healing abutments to demonstrate the possible improvements for tissue growth around dental implants. Harvested commercially pure titanium (cpTi) abutments from three clinical cases per group revealed that separation of the abutments from the human gingival tissues occurred mainly intercellularly rather than directly from the tissue, suggesting that placement of an RFGDT permanent abutment would trigger tissue-integration more completely than noted with usual alcohol-cleaned abutments. This work confirmed and extended observations of prior studies that RFGDT materials have mitogenic effects that might be captured for stimulating desired tissue growth around implanted biomaterial appliances. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 169-177, 2017.

Peri-implant disease: what we know and what we need to know.

Peri-implant disease is a serious problem that plagues today's dentistry, both in terms of therapy and epidemiology. With the expansion of the practice of implantology and an increasing number of implants placed annually, the frequency of peri-implant disease has greatly expanded. Its clinical manifestations, in the absence of a globally established classification, are peri-implant mucositis and peri-implantitis, the counterparts of gingivitis and periodontitis, respectively. However, many doubts remain about its features. Official diagnostic criteria, globally recognized by the dental community, have not yet been introduced. The latest studies using metagenomic methods are casting doubt on the assumption of microbial equivalence between periodontal and peri-implant crevices. Research on most of the features of peri-implant disease remains at an early stage; moreover, there is not a commonly accepted treatment for it. In any case, although the evidence so far collected is limited, we need to be aware of the current state of the science regarding this topic to better understand and ultimately prevent this disease.

Active implant peri-apical lesion: a case report treated via guided bone regeneration with a 5-year clinical and radiographic follow-up.

Implant peri-apical lesion (IPL) is a periapical lesion, usually asymptomatic, in which the coronal portion of the implant achieves a normal bone to implant interface. A case of IPL following immediate implant placement and treated with guided bone regeneration (GBR) principles is described. Five-year clinical and radiographic follow-up with cone-beam assessment showed complete healing of the bone. GBR principles applied to IPL could completely solve the lesion.

Primary stability comparison using piezoelectric or conventional implant site preparation systems in cancellous bone: a pilot study.

PURPOSE: This study compares implant primary stability achieved in cancellous bone after placement in piezoelectric prepared sites versus conventionally drilled sites. MATERIALS AND METHODS: Four bovine ribs were randomly assigned and placed in a water bath at 36.5 °C. Five sites per rib (total n = 20 sites) were prepared using piezoelectric system (test) or conventional drills (control) with twenty 10 × 3.6-mm Implantium implants placed. Using Osstell Mentor quantitative analysis, 5 resonance frequency analysis [implant stability quotient {ISQ}] values per implant were recorded at 5 locations for a total of 100 measurements. RESULTS: Independent t test analysis indicated significant difference in primary stabilities between groups: t (17) = 2.637, P = 0.17, with equal variance assumption satisfied (P = 0.196). Examination of means indicated a higher mean ISQ for piezoelectric than for conventional: 58.9 (+8.55) versus 49.2 (+7.33), respectively. Analysis of variance indicated a significant difference in mean ISQ value by rib. Tukey test indicated significantly higher ISQ values for rib A (test) than ribs B, C (control), and D (test). CONCLUSION: Implant site preparation using the piezoelectric system gives higher implant primary stability in cancellous bone. However, variations in quality across bones may have affected the results.