Clinical efficacy of subgingivally delivered 1.2-mg simvastatin in the treatment of individuals with Class II furcation defects: a randomized controlled clinical trial

The Use of Statins as an Adjunctive Periodontal Disease Treatment: Systematic Review and Meta-Analysis

BACKGROUND

the purpose of this systematic review was to assess the clinical and radiographic effect of subgingival-administered statins as an adjunct periodontal treatment in patients with periodontitis.

METHODS

Electronic literature searches in Medline/PubMed and the Cochrane Library were conducted to identify all relevant articles. Eligibility was based on inclusion criteria which included Randomized Controlled Trials (RCTs) published after 2010, where the periodontal variables were assessed before and after periodontal treatment in combination with a statin administration. The risk of bias was assessed with the ROBINS-2 tool. The outcome variables were probing depth, clinical attachment level, bleeding on probing, and bone fill in systematically healthy patients, patients with type 2 diabetes, and smokers.

RESULTS

Out of 119 potentially eligible articles, 18 randomized controlled trials were included with a total of 1171 participants. The data retrieved from the meta-analysis showed the positive effect that statins have as an adjunctive periodontal disease treatment. When comparing the different types of statins, the PD reduction in the Simvastatin group was significantly higher than the Atorvastatin group at 6 months and at 9 months, while no differences between statins were found for the rest of the outcomes. Over 66% of the articles presented an overall risk of bias with some concerns, making this a limitation of this present RCT.

CONCLUSIONS

The adjunct administration of statins has proven to have a positive effect on the periodontium by improving both clinical and radiographic parameters by a considerable margin.

Statins and oral biofilm: Simvastatin as a promising drug to control periodontal dysbiosis

OBJECTIVES

This study evaluated antimicrobial activity of atorvastatin, pravastatin, rosuvastatin, and simvastatin against oral bacteria, and the interaction of simvastatin with standard antimicrobials (amoxicillin and metronidazole).

METHODS

Minimal inhibitory concentration assays were performed with Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Actinomyces odontolyticus, Streptococcus oralis, Streptococcus mitis, Streptococcus salivarius, Streptococcus sanguinis, and Streptococcus gordonii; checkerboard microdilution assays between simvastatin and standard antimicrobials; monospecies and multispecies biofilms.

RESULTS

Simvastatin showed the best antimicrobial activity against most species (MIC range from 3.12 to 25 μg/ml), highlighting the sensitivity of P. gingivalis. In the checkerboard assay, synergistic interaction was found between simvastatin and amoxicillin against S. oralis and S. sanguinis. P. gingivalis biofilm was inhibited by simvastatin at 10 and 50× Minimal inhibitory concentration, with similar effects to metronidazole. For multispecies biofilm, SMV reduced the biofilm metabolic activity (79%) and total counts (87%), comparable to amoxicillin. Simvastatin also reduced bacterial counts of Veilonnella parvula, P. gingivalis, Streptococcus mutans, Actinomyces naeslundii, P. intermedia, and Capnocytophaga ochracea in the multispecies biofilm.

CONCLUSIONS

Simvastatin showed antimicrobial and antibiofilm activity against oral bacteria and may contribute to the control of dysbiosis, and may be considered in clinical studies as an adjuvant in the treatment of periodontitis.

Alveolar ridge splitting and simvastatin loaded xenograft for guided bone regeneration and simultaneous implant placement: randomized controlled clinical trial

OBJECTIVES

The present study goal was to assess clinically and radiographically using simvastatin (SMV) loaded xenograft for guided bone regeneration (GBR) around simultaneously placed implants with alveolar ridge splitting in patients with horizontally atrophic jaw defect.

MATERIALS AND METHODS

Randomized distribution of the twenty-two patients into two groups (11 patients each) was performed. Group I participants received alveolar ride splitting (ARS) with GBR using SMV gel mixed bone graft and a barrier membrane with simultaneous implant placement. Group II received the same treatment protocol without SMV gel. At the baseline, 6- and 9-months post-surgery, clinical and radiological alterations were assessed.

RESULTS

Six months after therapy, PES records of group I were statistically significantly improved than those of group II (P < .001). Group I exhibited statistically significant expansion of the alveolar ridge over group II after 6 and 9 months (P < .001). When compared to group II over the evaluation interval between 6 and 9 months, group I demonstrated statistically substantially minimal loss of the mean marginal bone level (P < .001). At the 6- and 9-month observation periods, bone density gain was considerably higher in group I than that in group II (P < .001).

CONCLUSION

Alveolar ridge splitting along with GBR-augmented SMV improve the clinical and radiographical outcomes around dental implant over GBR alone.

CLINICAL RELEVANCE

Augmenting GBR with SMV in alveolar ridge splitting could boost implant osseointegration and enhance peri-implant tissue changes.

CLINICAL TRIAL REGISTRATION

NCT05020405.

Regeneration of critical-sized grade II furcation using a novel injectable melatonin-loaded scaffold

BACKGROUND

Periodontal regenerative therapy using bone-substituting materials has gained favorable clinical significance in enhancing osseous regeneration. These materials should be biocompatible, osteogenic, malleable, and biodegradable. This study assessed the periodontal regenerative capacity of a novel biodegradable bioactive hydrogel template of organic-inorganic composite loaded with melatonin.

MATERIALS AND METHODS

A melatonin-loaded alginate-chitosan/beta-tricalcium phosphate composite hydrogel was successfully prepared and characterized. Thirty-six critical-sized bilateral class II furcation defects were created in six Mongrel dogs, and were randomly divided and allocated to three cohorts; sham, unloaded composite, and melatonin-loaded. Periodontal regenerative capacity was evaluated via histologic and histomorphometric analysis.

RESULTS

Melatonin-treated group showed accelerated bone formation and advanced maturity, with a significant twofold increase in newly formed inter-radicular bone compared with the unloaded composite. The short-term regenerative efficacy was evident 4 weeks postoperatively as a significant increase in cementum length concurrent with reduction of entrapped epithelium. After 8 weeks, the scaffold produced a quality of newly synthesized bone similar to normal compact bone, with potent periodontal ligament attachment.

CONCLUSIONS

Melatonin-loaded hydrogel template accelerated formation and enhanced quality of newly formed bone, allowing complete periodontal regeneration. Furthermore, the scaffold prevented overgrowth and entrapment of epithelial cells in furcation defects.

Exploring the Synergistic Effect of Simvastatin in Oral Health Applications: A Literature Review

Statins are the first line of treatment for hyperlipidaemia. Along with lowering lipids, it also lowers mortality and cardiovascular risk. Statins play a major role in maintaining the homeostasis of the oral cavity via a number of different mechanisms. It includes regeneration of dentin and pulp by differentiation and increased development of mineralized tissue via the bone morphogenetic proteins (BMP)-2 Pathway. It shows effective bone health by leading to osteogenic differentiation mesenchymal stem cells, by facilitating epithelization process in wound healing, anti-inflammatory, antioxidant, antimicrobial, antiviral, and fungicidal properties. To the finest of the information we have, there have been very few comprehensive studies that have investigated the effects of statin drugs on various aspects of dental and oral health. As a result, the main objective of this review was to examine the effect of statins on oral health applications. According to the findings of our extensive review, statins have noteworthy and promising effects on several aspects of oral health, including dental pulp cells, chronic periodontitis, alveolar bone loss, orthodontic tooth movement, and so on. Nevertheless, it is concluded that local or even systemic administration of simvastatin should be regarded as an innovative, easily accessible, and safe therapeutic agent that has a significant impact on enhancing the oral health.

The Effects of Statins on Bone Formation Around Implants Placed in Animal Bones: A Systematic Review and Meta-Analysis

Background

Implants are preferred for replacement of missing teeth by the clinicians as well as the patients. Lesser alveolar bone density doesn't preclude any individual for choosing this option but warrants for extra caution. Preclinical studies have explored the osteoinductive potential of statins, but results should be analyzed vigorously before implementing them in humans. There is no meta-analysis to document effect of statins on bone formation around implants in osteoporotic animals.

Methods and material

PubMed, Embase and Cochrane were searched for studies investigating the effect of statins on bone implant contact (BIC %), bone mineral density (BMD %) and bone volume (BV %) around implants at 2, 4 and 12 weeks. Meta-analysis was performed on subgroups with osteoporotic animals which were administered statins through different routes.

Results

Quantitative data from 12 studies showed favorable effect of statins on bone around implants. Positive difference was observed at 4 weeks in BIC (parenteral [SMD = 4.33 (2.89, 5.77); I 2 = 3%)], BMD (local [SMD = 1.33 (0.51, 2.15); I 2 = 0%] and BV (local [SMD = 1.58 (0.76, 2.40); I 2 = 0%]. BIC [SMD = 1.40 (0.89, 1.90); I 2 = 0%] and BV [SMD = 3.91 (2.33, 5.50); I 2 = 43%] were higher in experimental group after 12 weeks of oral administration.

Conclusions

Statins can be investigated as potential bone graft materials to increase the predictability of osseointegration especially in osteoporotic individuals. Future research should focus to reproduce homogeneous data and conclusive recommendations which can be applied in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-023-01873-z.

Local drug delivery in the treatment of furcation defects in periodontitis: a systematic review

OBJECTIVES

To evaluate the effect of subgingival administration of various antimicrobials and host-modulating agents in furcation defects as an adjunct to scaling and root planing (SRP) compared to SRP alone or combined with placebo.

METHODS

A systematic review was carried out using MEDLINE-PubMed, Embase, and Scopus for articles up to October 2022 in addition to hand searches. All longitudinal studies that evaluated the effect of subgingival application of antimicrobial and host-modulating agents in furcation defects as adjuncts to SRP compared to SRP alone or SRP + placebo with at least 3 months of follow-up were eligible for inclusion.

RESULTS

A total of eight studies were included. Superior clinical treatment outcomes were shown when alendronate, rosuvastatin, boric acid, simvastatin, and tetracycline (only at 3 months) were utilized in furcation defects in conjunction with SRP alone or SRP + placebo. Significant improvement was reported in radiographic bone defect depth and defect depth reduction when SRP was supplemented with alendronate, rosuvastatin, boric acid, and simvastatin.

CONCLUSIONS

Within the limitations of this review, the adjunctive subgingival administration of medications and host-modulating agents in furcation defects may confer additional clinical and radiographic benefits than non-surgical periodontal treatment alone. Future investigations are needed to confirm their long-term effectiveness.

CLINICAL RELEVANCE

Local host modulators and antimicrobials may be used supplementary to enhance the clinical and radiographic treatment outcomes of conventional periodontal therapy in furcation defects.

Sub-gingival delivery of simvastatin and rosuvastatin for treatment of chronic periodontitis with diabetes mellitus: A randomized controlled clinical-radiographic pilot study

Background

Statins are lipid-lowering medications that work by blocking rate-limiting enzyme in cholesterol formation. In patients with Chronic periodontitis (CP) and Diabetes mellitus (DM), subgingival delivery of simvastatin (SMV) and rosuvastatin (RSV) have demonstrated to have bone-stimulatory and anti-inflammatory properties. The current study intended to assess and compare the efficacy of sub-gingivally delivered SMV gel and RSV gel as an adjunctive medication to scaling and root planing (SRP) in the management of intrabony defects in CP patients with type 2 DM.

Methods

30 patients with CP and type 2 DM were classified into three treatment groups - SRP + placebo, SRP +1.2% SMV and SRP +1.2% RSV. Clinical parameters: site-specific plaque index, modified sulcus bleeding index (mSBI), pocket probing depth (PPD), and relative attachment level (RAL) were documented at baseline, 3 and 6 months and radiographic parameter: intrabony defect depth (IBD) at baseline and 6 months post-treatment.

Results

- LDD of 1.2% SMV and 1.2% RSV demonstrated greater clinical and radiographic improvement than placebo, the improvement being statistically significant for PI, mSBI, and PPD for 1.2% SMV and statistically significant for all clinical and radiological parameters for the 1.2% RSV. 1.2% RSV demonstrated greater IBD fill and RAL gain than 1.2% SMV.

Conclusion

- Localized sub-gingival delivery of statins was beneficial in the treatment intrabony defects in patients with CP and well-controlled type 2 DM. IBD fill and RAL gain were higher with 1.2% RSV than with 1.2% SMV.

The Effect of Locally Applied Simvastatin on Clinical Attachment Level and Alveolar Bone in Periodontal Maintenance Patients: Randomized Clinical Trial

BACKGROUND

The purpose of this double-masked, randomized, controlled trial was to determine if the local application of simvastatin (SIM), combined with minimally invasive papilla reflection and root preparation (PR/RP), is effective in improving clinical attachment level (CAL), probing depth (PD) reduction, and increasing interproximal bone height (IBH) in persistent 6-9 mm periodontal pockets in patients receiving periodontal maintenance therapy (PMT).  METHODS: : Fifty patients with Stage III, Grade B periodontitis presenting with a 6-9 mm interproximal PD with a history of bleeding on probing (BOP) were included in the study. Experimental [PR/RP+SIM/methylcellulose (MCL); n=27] and control (PR/RP + MCL; n=23) therapies were randomly assigned.  Root surfaces were accessed via reflection of interproximal papillae, followed by root planing assisted with endoscope evaluation, acid etching, and SIM/MCL or MCL application.  CAL, PD, BOP, plaque presence and IBH (using standardized vertical bitewing radiographs) were evaluated at baseline and 12 months. Measurements were compared by group and time using Chi-square, Wilcoxon rank sum, and t-tests.

RESULTS

Both PR/RP+SIM/MCL and PR/RP+MCL, respectively, resulted in improvements in clinical outcomes (CAL: -1.9 ± 0.3 mm, p<0.0001; -1.0 ± 0.3 mm, p<0.003; PD:  -2.3 mm ± 0.3, p<0.0001; -1.3 mm ± 0.3, p<0.0001; BOP: -58.7%; -41.7%, p<0.05) and stable IBH (-0.2 ± 0.12, -0.4 ± 0.2, p=0.22) from baseline to 12 months post-therapy. PR/RP+SIM/MCL had more improvement in CAL (p=0.03), PD (p=0.007), and BOP (p=0.047).

CONCLUSIONS

The addition of SIM/MCL to PR/RP improved CAL, PD, and BOP compared to PR/RP alone in periodontal maintenance patients. This article is protected by copyright. All rights reserved.

STATINSWITH POTENTIAL TO CONTROL PERIODONTITIS: FROM BIOLOGICAL MECHANISMS TO CLINICAL STUDIES

BACKGROUND

Statins are widely used for the treatment of hyperlipidemia. However, these drugs have pleiotropic effects that can be promising for the prevention and treatment of oral diseases, such as periodontitis.

HIGHLIGHT

This review aimed to identify preclinical, observational, and clinical studies that evaluate the effects and biological mechanisms of statins on oral cells and tissues and those using these drugs to treat periodontitis. A LITERATURE SURVEY HAS BEEN CONDUCTED IN PUBMED USING COMBINATIONS OF THE UNITERMS: "statins," "dentistry," "periodontal disease," and "periodontal treatment." In vitro findings showed positive statin results in cell lines related to alveolar bone metabolism by altering the signaling pathway Osteoprotegerin/Receptor Activator of Nuclear Factor Kappa B/Receptor Activator of Nuclear Factor Kappa B Ligand (OPG/RANK/RANKL), stimulating the production of alkaline phosphatase and osteocalcin, and reducing the production of matrix metalloproteinases (MMPs). Animal studies have shown a reduction in alveolar bone loss and osteoclastic activity, in addition to a reduction in inflammatory markers, such as IL-1, IL-6, and TNF-α, when statins were used prophylactically. Clinical trials showed a positive impact on clinical parameters, leading to a higher reduction in probing depth and gain in clinical attachment when a local statin was adjunctively associated with mechanical therapy.

CONCLUSION

Statins were shown to be promising for regenerating and stimulating bone activity, with great potential for treating chronic periodontitis. However, further studies are required to confirm its effectiveness.

Clinical efficacy of simvastatin gel combined with polypropylene membrane on the healing of extraction sockets: A triple-blind, randomized clinical trial

OBJECTIVES

This study aimed to evaluate dimensional changes, level of soft tissue healing, and pain/discomfort perception in post-extraction sockets filling with 1.2% simvastatin (SIM) gel covered with polypropylene membranes (PPPM).

MATERIAL AND METHODS

Twenty-six post-extraction sockets of posterior teeth were randomly allocated in two groups: (a) socket filling with 1.2% SIM gel and covered with PPPM (n = 13) and (b) socket filling with placebo gel and covered with PPPM (n = 13). Cone-beam computed tomography (CBCT) images before and 90 days after the extraction enabled alveolar bone dimensional changes calculation using horizontal and vertical measurements. The measurements occurred at three different levels for thickness located 1, 3, and 5 mm from the top of the bone crest. The vertical (depth) measure was assessed from the most apical portion of the socket to the bone crest's most coronal portion. Seven days after the extractions, the level of soft tissue healing and pain perception were also analyzed.

RESULTS

After 90 days of extractions, the dimensional changes in thickness in the test group were significantly smaller in sections A (p = .044), B (p = .036) and C (p = .048) when compared to the control group. The test group showed a significantly lower height-dimensional change than the control group (p < .0001). Soft tissue healing index (p = .63), perception of pain (p = .23), and number of analgesics consumed (p = .25) were similar between groups.

CONCLUSIONS

Simvastatin at 1.2% compared with placebo effectively reduced the dimensional changes in post-extraction sockets covered with PPPM. There was no significant difference in the level of soft tissue healing and postoperative pain between the test and control groups.

Thermoresponsive Hydrogel-Based Local Delivery of Simvastatin for the Treatment of Periodontitis

Except for routine scaling and root planing, there are few effective nonsurgical therapeutic interventions for periodontitis and associated alveolar bone loss. Simvastatin (SIM), one of the 3-hydroxy-3-methylglutaryl-cosenzyme A reductase inhibitors, which is known for its capacity as a lipid-lowering medication, has been proven to be an effective anti-inflammatory and bone anabolic agent that has shown promising benefits in mitigating periodontal bone loss. The local delivery of SIM into the periodontal pocket, however, has been challenging due to SIM's poor water solubility and its lack of osteotropicity. To overcome these issues, we report a novel SIM formulation of a thermoresponsive, osteotropic, injectable hydrogel (PF127) based on pyrophosphorolated pluronic F127 (F127-PPi). After mixing F127-PPi with F127 at a 1:1 ratio, the resulting PF127 was used to dissolve free SIM to generate the SIM-loaded formulation. The thermoresponsive hydrogel's rheologic behavior, erosion and SIM release kinetics, osteotropic property, and biocompatibility were evaluated in vitro. The therapeutic efficacy of SIM-loaded PF127 hydrogel on periodontal bone preservation and inflammation resolution was validated in a ligature-induced periodontitis rat model. Given that SIM is already an approved medication for hyperlipidemia, the data presented here support the translational potential of the SIM-loaded PF127 hydrogel for better clinical management of periodontitis and associated pathologies.

The effects of statins on dental and oral health: a review of preclinical and clinical studies

The statin family of drugs are safe and effective therapeutic agents for the treatment of arteriosclerotic cardiovascular disease (CVD). Due to a wide range of health benefits in addition to their cholesterol lowering properties, statins have recently attracted significant attention as a new treatment strategy for several conditions, which are not directly related to normalizing a lipid profile and preventing CVD. Statins exert a variety of beneficial effects on different aspects of oral health, which includes their positive effects on bone metabolism, their anti-inflammatory and antioxidant properties, and their potential effects on epithelization and wound healing. Additionally, they possess antimicrobial, antiviral, and fungicidal properties, which makes this class of drugs attractive to the field of periodontal diseases and oral and dental health. However, to the best of our knowledge, there has been no comprehensive study to date, which has investigated the effects of statin drugs on different aspects of dental and oral health. Therefore, the primary objective of this paper was to review the effect of statins on dental and oral health. Results of our extensive review have indicated that statins possess remarkable and promising effects on several aspects of dental and oral health including chronic periodontitis, alveolar bone loss due to either extraction or chronic periodontitis, osseointegration of implants, dental pulp cells, orthodontic tooth movement, and orthodontic relapse, tissue healing (wound/bone healing), salivary gland function, and finally, anti-cancer effects. Hence, statins can be considered as novel, safe, inexpensive, and widely-accessible therapeutic agents to improve different aspects of dental and oral health.

Effect of Simvastatin on Bone Regeneration: A Histologic and Histomorphometric Analysis

PURPOSE

The purpose of the present study was to evaluate the efficacy of simvastatin administration as an osteoinductive agent combined with bovine bone material (BBM) for augmentation of human maxillary sinuses.

MATERIALS AND METHODS

In the present randomized clinical trial with a split-mouth design, 24 maxillary sinuses in 12 patients were augmented using BBM alone or BBM combined with simvastatin. Biopsy samples were taken 9 months after maxillary sinus floor augmentation for histologic and histomorphometric analyses. A total of 44 implants were placed in the augmented bone.

RESULTS

The results of the microscopic assessment of most samples revealed no inflammation or only mild chronic inflammation. Lamellation was detectable in old bone trabeculae under polarized light microscopy but was not observed in newly formed bone. Osteocytes were found with a lower frequency in the lacunae of newly formed bone compared with normal bone. No significant differences were found in the amount of newly formed bone and the amount of residual particles between the 2 groups.

CONCLUSIONS

Despite the greater mean percentage of newly formed bone in the test group, the histomorphometric analysis results did not show a significant positive effect for the use of simvastatin in maxillary sinus augmentation.

Guided tissue regeneration of intrabony defects with perforated barrier membranes, simvastatin, and EDTA root surface modification: A clinical and biochemical study

BACKGROUND

Perforated barrier membranes (PBM) were suggested to enhance periodontal regeneration by allowing positive charity of wanted elements from the gingival tissue side. The present study was designed to evaluate clinically and biochemically the use of PBM combined with simvastatin (SMV) gel with and without an associated EDTA gel root surface etching as a suggested option that could improve SMV availability and clinical outcomes of PBM.

METHODS

Forty patients having moderate-to-severe chronic periodontitis with 40 intrabony defects were randomly divided into four treatment groups (10 sites each). Patients in group 1 received 1.2% SMV gel and covering the defect with occlusive membrane (OM). Patients in group 2 received 1.2% SMV gel and covering the defect with PBM. Group 3 received 24% EDTA root surface etching, 1.2% SMV gel, and defect coverage with OM (eOM). Patients in group 4 were treated as in group 3 but the defect was covered with PBM (ePBM). Clinical parameters were recorded at baseline before surgical procedures and were reassessed at 6 and 9 months after therapy. The mean concentration of SMV in gingival crevicular fluid (GCF) was estimated by reverse-phase high-performance liquid chromatography at days 1, 7, 14, 21, and 30.

RESULTS

At 6- and 9-month observation periods, groups 3 and 4 showed a statistically significant improvement in PD reduction and CAL gain compared with groups 1 and 2. Group 4 showed a statistically significant more defect fill compared with groups 1, 2, and 3 (P ≤ .05). Group 2 showed statistically significant higher defect fill compared with group 1 and group 3 (P < .05). Bone density was significantly increased with no significant difference between the four groups at 6- and 9-month observation periods. SMV-GCF concentration in group 4 showed the highest mean concentration with no significant difference than that of group 3.

CONCLUSION

The use of perforated barrier membranes in association with SMV enhances the clinical hard tissue parameters compared with occlusive ones in treating intrabony periodontal defects. Moreover, EDTA root surface treatment could enhance SMV availability in the defect area.

Efficacy of locally-delivered statins adjunct to non-surgical periodontal therapy for chronic periodontitis: a Bayesian network analysis

BACKGROUND

Studies indicate locally-delivered statins offer additional benefits to scaling and root planning (SRP), however, it is still hard to say which type of statins is better. This network meta-analysis aimed to assess the effect of locally-delivered statins and rank the most efficacious statin for treating chronic periodontitis (CP) in combination with SRP.

METHODS

We screened four literature databases (Pubmed, Embase, Cochrane Library, and Web of Science) for randomized controlled clinical trials (RCTs) published up to June 2018 that compared different statins in the treatment of chronic periodontitis. The outcomes analyzed were changes in intrabony defect depth (IBD), pocket depth (PD), and clinical attachment level (CAL). We carried out Bayesian network meta-analysis of CP without systemic diseases. Traditional and Bayesian network meta-analyses were conducted using random-effects models.

RESULTS

Greater filling of IBD, reduction in PD, and gain in CAL were observed for SRP treated in combination with statins when compared to SRP alone for treating CP without systemic diseases. Specifically, SRP+ Atorvastatin (ATV) (mean difference [MD]: 1.5 mm, 1.4 mm, 1.8 mm, respectively), SRP + Rosuvastatin (RSV) (MD: 1.8 mm, 2.0 mm, 2.1 mm, respectively), and SRP + Simvastatin (SMV) (MD: 1.1 mm, 2.2 mm, 2.1 mm, respectively) were identified. However, no difference was found among the statins tested. In CP patients with type 2 diabetic (T2DM) or in smokers, additional benefits were observed from locally delivered statins.

CONCLUSION

Local statin use adjunctive to SRP confers additional benefits in treating CP by SRP, even in T2DM and smokers. RSV may be the best one to fill in IBD. However, considering the limitations of this study, clinicians must use cautious when applying the results and further studies are required to explore the efficacy of statins in CP with or without the risk factors (T2DM comorbidity or smoking history).

The impact of simvastatin intervention on the healing of bone, soft tissue, and TMJ cartilage in dentistry: a systematic review and meta-analysis

The review aimed at assessing the osteopromotive potential as well as soft tissue and temporomandibular joint (TMJ) cartilage healing properties of simvastatin by summarizing its efficacy on the current dental treatment of periodontal bone and soft tissue defects, and temporomandibular joint (TMJ) arthritis from the available animals and human studies. An electronic search was performed on MEDLINE, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) using a combination of keywords. A hand search was undertaken on seven oral surgery journals. No limitation of publication year in the English language was placed. Controlled randomized animal and human clinical trials, as well as prospective comparative studies, were included. Data on the comparison of topical/systemic simvastatin on bone healing in intrabony and furcation defects, extraction sockets, distraction osteogenesis, as well as soft tissue healing in mucogingival grafting procedures and cartilage protection in TMJ arthritis were extracted from all the eligible studies. Studies with a minimum of ten participants and follow up at least 6 months were included. Ten animal studies and six clinical studies were included in this study. All the animal studies included a minimum of eight sites per group assessed clinically, histologically, and radiographically. All human studies included clinical and radiological evaluation. The results of the review show that simvastatin administration displays positive treatment outcomes in the full range of therapies investigated in the oral regions such as periodontal infection control, periodontal and alveolar bone regeneration, soft tissue grafting, TMJ inflammation reduction, and cartilage repair. Its mechanism includes stimulating bone formation, promoting soft tissue healing, increasing articular and condylar cartilage thickness, as well as reducing inflammation at surgical sites in TMJ disorders. Simvastatin administration is beneficial to the healing of oral bone and cartilage. More studies are desired to determine its potential in soft tissue healing.

Contribution of Statins towards Periodontal Treatment: A Review

The pleiotropic effects of statins have been evaluated to assess their potential benefit in the treatment of various inflammatory and immune-mediated diseases including periodontitis. Herein, the adjunctive use of statins in periodontal therapy in vitro, in vivo, and in clinical trials was reviewed. Statins act through several pathways to modulate inflammation, immune response, bone metabolism, and bacterial clearance. They control periodontal inflammation through inhibition of proinflammatory cytokines and promotion of anti-inflammatory and/or proresolution molecule release, mainly, through the ERK, MAPK, PI3-Akt, and NF-κB pathways. Moreover, they are able to modulate the host response activated by bacterial challenge, to prevent inflammation-mediated bone resorption and to promote bone formation. Furthermore, they reduce bacterial growth, disrupt bacterial membrane stability, and increase bacterial clearance, thus averting the exacerbation of infection. Local statin delivery as adjunct to both nonsurgical and surgical periodontal therapies results in better periodontal treatment outcomes compared to systemic delivery. Moreover, combination of statin therapy with other regenerative agents improves periodontal healing response. Therefore, statins could be proposed as a potential adjuvant to periodontal therapy. However, optimization of the combination of their dose, type, and carrier could be instrumental in achieving the best treatment response.

Identification of Genes Differentially Expressed in Simvastatin-Induced Alveolar Bone Formation

Local delivery of simvastatin (SIM) has exhibited potential in preventing inflammation and limiting bone loss associated with experimental periodontitis. The primary aim of this study was to analyze transcriptome changes that may contribute to SIM's reduction of periodontal inflammation and bone loss. We evaluate the global genetic profile and signaling mechanisms induced by SIM on experimental periodontitis bone loss and inflammation. Twenty mature female Sprague Dawley rats were subjected to ligature-induced experimental periodontitis around maxillary second molars (M2) either unilaterally (one side untreated, n = 10) or bilaterally (n = 10). After the ligature removal at day 7, sites were injected with either carrier, pyrophosphate (PPi ×3), 1.5-mg SIM-dose equivalent SIM-pyrophosphate prodrug, or no injection. Three days after ligature removal, animals were euthanized; the M1-M2 interproximal was evaluated with μCT, histology, and protein expression. M2 palatal gingiva was harvested for RNA sequencing. Although ligature alone caused upregulation of proinflammatory and bone catabolic genes and proteins, seen in human periodontitis, SIM-PPi upregulated anti-inflammatory (IL-10, IL-1 receptor-like 1) and bone anabolic (insulin-like growth factor, osteocrin, fibroblast growth factor, and Wnt/ β-catenin) genes. The PPi carrier alone did not have these effects. Genetic profile and signaling mechanism data may help identify enhanced pharmacotherapeutic approaches to limit or regenerate periodontitis bone loss. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

Simvastatin attenuates tibial bone loss in rats with type 1 diabetes and periodontitis

Background

Diabetes induces long bone loss and aggravation of periodontitis-induced alveolar bone loss. Simvastatin (SIM), which is a lipid-lowering agent is known to have an anabolic effect on bone. Therefore, we investigated effect of SIM on tibial and alveolar bone loss in type 1 diabetic rats with periodontitis.

Methods

Rats were divided into control (C), diabetes with periodontitis (DP), and diabetes with periodontitis treated with SIM (DPS) groups. DP and DPS groups were intravenously injected with streptozotocin (50 mg/kg), and C group was injected with citrate buffer. Seven days later (day 0), periodontitis was induced by ligatures of mandibular first molars. DP and DPS groups were orally administered vehicle or SIM (30 mg/kg) from day 0 to days 3, 10, or 20. Alveolar and tibial bone loss was measured using histological and m-CT analysis alone or in combination. Osteoclast number and sclerostin-positive osteocytes in tibiae were evaluated by tartrate-resistant acid phosphatase and immunohistochemical staining, respectively. Glucose, triglyceride (TG), cholesterol (CHO), and low-density lipoprotein (LDL) were evaluated.

Results

Consistent with diabetes induction, the DP group showed higher glucose and TG levels at all timepoints and higher CHO levels on day 20 than C group. Compared to the DP group, the DPS group exhibited reduced levels of glucose (day 3), TG (days 10 and 20), CHO, and LDL levels (day 20). Bone loss analysis revealed that the DP group had lower bone volume fraction, bone mineral density, bone surface density, and trabecular number in tibiae than C group at all timepoints. Interestingly, the DPS group exhibited elevation of these indices at early stages compared to the DP group. The DPS group showed reduction of osteoclasts (day 3) and sclerostin-positive osteocytes (days 3 and 20) compared with the DP group. There was no difference in alveolar bone loss between DP and DPS groups.

Conclusions

These results suggest that SIM attenuates tibial, but not alveolar bone loss in type 1 diabetic rats with periodontitis. Moreover, attenuation of tibial bone loss by SIM may be related to inhibition of osteoclast formation and reduction of sclerostin expression.

Graftless Maxillary Sinus Lift Using Lateral Window Approach: A Systematic Review

PURPOSE

The aim was to determine the survival rate of dental implants installed in the posterior region of the maxilla after a graftless maxillary sinus lift via the lateral window approach and to identify the factors involved in the results.

MATERIALS AND METHODS

A systematic search was done on MEDLINE, EMBASE, LILACS, Scopus, and Science Direct up to June 2016; additional studies were identified through an analysis of references. Primary studies in English, Spanish, Portuguese, and French were included; the selection and data extraction process was conducted by 2 investigators independently, and the methodological quality was evaluated by means of the Effective Public Health Practice Project's Quality Assessment Tool.

RESULTS

The combined search identified 232 articles. After the selection process, 11 articles were identified, 9 of which were prospective and 2 were retrospective. In all of them, the graftless maxillary sinus lift was done with the immediate installation of the implant. All the studies included presented a low methodological quality. The mean survival rate of the implants was 97% with an average new intrasinus bone formation of 6.2 mm.

CONCLUSION

This technique has a high implant survival although it is not possible to identify its correct indication and contraindication.

The effect of local and systemic statin use as an adjunct to non-surgical and surgical periodontal therapy-A systematic review and meta-analysis

OBJECTIVES

To evaluate the effect of local and/or systemic statin use as an adjunct to non-surgical and/or surgical periodontal therapy.

DATA

Literature search according to PRISMA guidelines with the following eligibility criteria: (a) English or German language; (b) interventional studies; (c) statins as monotherapy or as an adjunct to non-surgical and/or surgical treatment of periodontitis; (d) clinical and/or radiographic treatment effect size of statin intake reported.

SOURCES

Medline (PubMed), Embase (Ovid), CENTRAL (Ovid).

STUDY SELECTION

Thirteen clinical studies regarding local application and 2 with systemic administration of statins as an adjunct to non-surgical treatment (SRP) and 4 studies regarding intrasurgical statin application with a maximum follow-up of 9 months could be included; simvastatin, atorvastatin, and rosuvastatin were used. Local but not systemic statin application as an adjunct to SRP yielded significantly larger probing pocket depth (PD), radiographic defect depth (RDD), and bleeding index reduction, and larger clinical attachment level gain, and less residual PD and RDD (p≤0.016); rosuvastatin appeared as the most efficacious. Three of 4 studies reported a significant positive effect of intrasurgical statin application. No adverse events were reported after statin use. The vast majority of the included studies were from the same research group.

CONCLUSIONS

Significant additional clinical and radiographic improvements are obtained after local, but not systemic, statin use as an adjunct to SRP in deep pockets associated with intrabony defects and seemingly with furcation defects; intrasurgical statin application seems similarly beneficial. Confirmation of these results, and especially of the effect size, from other research groups is warranted.

Immunohistopathologic evaluation of Drynaria fortunei rhizome extract in the management of Class II furcation defects in a canine model

BACKGROUND

Management of furcation defects is still a challenging subject in periodontal therapy. Drynaria fortunei (Df) is a common type of traditional Chinese herb in the area of orthopedics and traumatology. In vitro and tissue engineering studies have shown that Df induces osteoblastic proliferation and promotes the differentiation of human periodontal ligament cells. This study investigated the management of Class II furcation defects in dogs using guided tissue regeneration (GTR) and Df granules mixed with β-tricalcium phosphate (β- TCP) alloplast.

METHODS

Sixteen Class II critical-sized furcation defects were surgically created in four mongrel dogs: Eight defects were treated with GTR and Df granules mixed with (β-TCP) alloplast served as the experimental group, while the other eight were managed with GTR and alloplast, served as control. Dogs were sacrificed at 4 and 8 weeks and the premolars were processed for the evaluation of treatment outcome including; osteoblastic count (OC), cementum layer thickness (CLT), percentage of collagen in bone matrix (CBM), and alkaline phosphatase (ALP) immunoreaction.

RESULTS

Experimental group treated with Df showed a significant increase (P < 0.001) in the values of OC, CLT, CBM, and ALP immunoreactivity when compared with control at 4 and 8 weeks after treatment.

CONCLUSION

Drynaria fortunei demonstrated increased regeneration and bone formation when used in the treatment of furcation defects in a canine model.

The effect of statins on periodontal treatment-a systematic review with meta-analyses and meta-regression

OBJECTIVE

This study aimed to systematically review clinical trials about the effect of statins as adjunct to mechanical periodontal therapy, on probing pocket depth, clinical attachment level, and intrabony defects, in comparison to mechanical periodontal therapy alone or in association with placebo.

MATERIAL AND METHODS

Three databases were searched for controlled clinical trials that used any locally delivered or systemically statin as a sole adjunctive therapy to mechanical periodontal treatment. Weighted mean differences between baseline and 6 months after periodontal treatment for clinical attachment level (CAL), probing pocket depth (PPD), and intrabony defect (IBD) were calculated. A high heterogeneity was detected. Therefore, a meta-regression adjusted for type of statin and year of publication was performed.

RESULTS

Fifteen studies were included in the systematic review, and ten studies were included in the meta-analysis. In the meta-regression, the adjunct use of simvastatin, rosuvastatin, and atorvastatin additionally reduced PPD in comparison to mechanical periodontal therapy and a placebo gel (2.90 ± 0.35, 3.90 ± 0.77, 3.06 ± 0.71 mm, respectively; p < 0.05). Regarding the resolution of IBD, simvastatin and rosuvastatin significantly improved in comparison to control group (0.89 ± 0.35 and 1.93 ± 0.77 mm, respectively; p < 0.05). No statistically significant difference was found between the statins for both PPD and IBD (p < 0.05). Regarding CAL gain, simvastatin provided a statistically significant improvement as compared to the control group (2.02 ± 0.79 mm; p = 0.043).

CONCLUSIONS

The use of statins, used as sole adjuncts to mechanical periodontal treatment, improved the periodontal parameters. In the quantitative analyses, simvastatin was the only drug that showed additional benefits in all evaluated parameters.

CLINICAL RELEVANCE

Statins promote significantly clinical periodontal improvements when administered in association with non-surgical scaling and root planning (SRP), when compared to SRP alone or in association with a placebo.

Efficacy of statin delivery as an adjunct to scaling and root planing in the treatment of chronic periodontitis: A meta-analysis

The action of statins in stimulating bone formation and having other pleiotropic effects, such as anti-inflammatory and immunomodulatory effects, has justified their use as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis (CP). The aim of the present study was to evaluate the efficacy of statin delivery as an adjunct to SRP in the treatment of CP. Electronic searches were conducted using the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, up until July 2017. The primary outcome was probing depth (PD), while the secondary outcomes were changes in clinical attachment level (CAL) and bone defect (BD) fill. Eleven studies were included, and all showed significant PD reduction, CAL gain, and BD fill with adjunctive statin delivery compared to SRP alone. The meta-analysis showed significant improvement in periodontal parameters for atorvastatin (PD: weighted mean difference [WMD] = -1.84, -2.56 to -1.12, P < .001; CAL: WMD = -2.31, -3.58 to -1.03, P < .001; BD fill: WMD = 2.66, -3.92 to -1.39, P < .001), simvastatin (PD: WMD = -1.91, -2.27 to -1.55, P < .001; CAL: WMD = -1.91, -2.27 to -1.55, P = .001; BD: WMD = -1.52, -2.20 to -0.85, P < .001), and rosuvastatin (PD: WMD = -0.94, -1.32 to -0.55, P < .001; CAL: WMD = -1.00, -1.41 to -0.60, P < .001; BD fill: WMD = -1.30, -1.80 to -0.79, P < .001). Adjunctive statin delivery appears to be effective in reducing PD, CAL gain, and BD fill in CP, and therefore, these drugs could be a promising therapeutic option for periodontal regeneration in future.

Does the adjunctive use of statins provide additional benefits to nonsurgical periodontal treatment? A systematic review and meta-analysis

Adjunctive therapeutic agents may be used to improve the response to nonsurgical periodontal therapy. Local delivery of statins (simvastatin, artovastatin and rosuvastatin) is a promising adjunct to scaling and root planing (SRP). Thus, the aim of this review is to evaluate if adjunctive local delivery of statins is more effective than SRP alone. Randomized clinical trials that presented a test group evaluating local delivery of statins as adjuncts in healthy, diabetic and smoking patients were included. Medline and the Cochrane library database were searched up to November 2016. Random effects meta-analyses were conducted for pocket depth change and clinical attachment gain. One hundred and twenty-five studies potentially related to the aim of this review were screened, but only 10 were included. The majority of the trials reported additional clinical benefits in the groups that were treated with adjunctive local delivery of statins. Pooled calculations showed that local delivery of statins resulted in additional reduction of pocket depth and clinical attachment gain in healthy people, smokers and diabetic patients. Local statins may offer additional clinical benefits to SRP, even in smokers and diabetics.

Harnessing cAMP signaling in musculoskeletal regenerative engineering

This paper reviews the most recent findings in the search for small molecule cyclic AMP analogues regarding their potential use in musculoskeletal regenerative engineering.

Effect of 1.2% of simvastatin gel as a local drug delivery system on Gingival Crevicular Fluid interleukin-6 & interleukin-8 levels in non surgical treatment of chronic periodontitis patients

AIM

The present study was carried out to evaluate the effect of 1.2% simvastatin gel as local drug delivery (LDD) system on Gingival Crevicular Fluid (GCF) Interleukin -6 (IL-6) and Interleukin-8 (IL-8) levels in chronic periodontitis patients, in addition to scaling and root planing (SRP).

METHODS

A total of 46 chronic periodontitis patients were equally divided into two groups. Group I patients were treated by SRP; Group II patients were treated by SRP followed by LDD of 1.2% simvastatin (SMV) gel. Plaque index (PI), Gingival index(GI), Sulcus Bleeding Index (SBI), Probing pocket depth (PPD) and Relative clinical attachment level (CAL) were recorded & GCF samples were collected at baseline (0day) and at 45th day from both the groups. The collected GCF samples were analysed for IL-6 and IL-8 levels with enzyme-linked immunosorbent assay (ELISA).

RESULTS

Both the groups showed significant reduction in all the clinical parameters scores and IL-6 and IL-8 levels after non-surgical periodontal therapy (SRP for group I/SRP+1.2% SMV gel for group II) in contrast to baseline values. However, a greater reduction was observed in group II. A non-significant positive correlation was observed between clinical parameters and IL-6 and IL-8 levels except at baseline, a significant correlation was observed between PPD &IL 6 levels in group II.

CONCLUSIONS

In adjunct to SRP, 1.2% Simvastatin gel acts as an effective local drug delivery agent for the management of chronic periodontitis.

Effect of in-situ application of simvastatin gel in surgical management of osseous defects in chronic periodontitis-A randomized clinical trial

BACKGROUND

The present randomized controlled clinical study was designed to investigate the effect of in situ application of 1.2 mg Simvastatin (SV) gel in the surgical management of Intrabony defects in chronic periodontitis patients.

METHODOLOGY

20 patients contributing 40 sites were categorized into two treatment groups: Open flap debridement plus 1.2 mg SV gel (Group 1) and Open flap debridement plus Placebo gel (Group 2). Gingival index (GI), Plaque index (PI), Pocket depth (PD) and clinical attachment level (CAL) were recorded at baseline, 3 months, 6 months and 9 months. At baseline and at the end of 6 and 9 months Radiographic evaluation of Intrabony defect fill was done using Image j software.

RESULTS

Significant reduction of GI, PD and gain in CAL was observed at the end of 9 months in both groups. Amount of bone fill and percentage of original defect fill in Group 1 was statistically highly significant than Group 2 at the end of 6 and 9 months.

CONCLUSION

Higher amount of decrease in GI and PD along with more amount of CAL gain was observed in treatment group than control group. Radiological assessment confirmed that significant intrabony defect fill and percentage fill of original defect in treatment group than controlled group.

The Effect of Locally Delivered Statins on Treating Periodontal Intrabony Defects: A Systematic Review and Meta-Analysis

BACKGROUND

Use of statins on adult patients with chronic periodontitis shows a positive effect on their periodontal status. However, effect of locally delivered statins on periodontal treatment has not yet been systematically analyzed. Hence, the present systematic review and meta-analysis aims to evaluate efficacy of statins on treating localized periodontal intrabony defects (IBDs).

METHODS

An electronic search of three databases (PubMed, Embase, and Cumulative Index to Nursing and Allied Health Literature) between January 1, 1965 and March 1, 2016, and a hand search of peer-reviewed journals for relevant articles were performed. Controlled randomized clinical trials (RCTs) and prospective studies with data on comparison between adjunctive locally delivered statin use to mechanical scaling and root planing (SRP) and placebo in each group, with minimum 10 participants and follow-up period of at least 6 months, were included.

RESULTS

Ten studies, eight RCTs and two prospective studies, were included. Each study included 15 to 105 patients between 25 and 55 years of age. Statistical results were recorded; weighted mean difference (WMD) and confidence interval (CI) were calculated; and meta-analyses were performed for defect fill, probing depth (PD) reduction, and clinical attachment level (CAL) gain in both statin and placebo/no treatment groups. Overall analysis of defect fill presented WMD of 1.37 mm (95% CI = 0.96 to 1.77; P <0.0001), PD reduction presented WMD of 1.76 mm (95% CI = 1.04 to 2.47; P <0.0001), and CAL gain presented WMD of 1.58 mm (95% CI = 0.89 to 2.28; P <0.0001). However, comparison presented considerable heterogeneity among studies.

CONCLUSIONS

This systematic review and meta-analysis find that adjunctive use of locally delivered statins to mechanical SRP is beneficial to increasing bone fill percentage. Improved inflammatory and bleeding control as well as PD reduction and CAL gain are possible advantages to using these drugs in treating patients with periodontal IBDs.

pH-Responsive Hydrogel With an Anti-Glycation Agent for Modulating Experimental Periodontitis

BACKGROUND

Stimulus-responsive devices have emerged as a novel approach for local drug delivery. This study investigates the feasibility of a novel chitosan-based, pH-responsive hydrogel loaded with N-phenacylthiazolium bromide (PTB), which cleaves the crosslinks of advanced glycation end products on the extracellular matrix.

METHODS

A chitosan-based hydrogel loaded with PTB was fabricated, and the in vitro release profile was evaluated within pH 5.5 to 7.4. BALB/cJ mice and Sprague-Dawley rats were used to evaluate the effects during the induction and recovery phases of periodontitis, respectively, and animals in each phase were divided into four groups: 1) no periodontitis induction; 2) ligature-induced experimental periodontitis (group PR); 3) experimental periodontitis plus hydrogel without PTB (group PH); and 4) experimental periodontitis plus hydrogel with PTB (group PP). The therapeutic effects were evaluated by microcomputed tomographic imaging of periodontal bone level (PBL) loss and histomorphometry for inflammatory cell infiltration and collagen density.

RESULTS

PTB was released faster at pH 5.5 to 6.5 and consistently slower at pH 7.4. In the induction phase, PBL and inflammatory cell infiltration were significantly reduced in group PP relative to group PR, and the loss of collagen matrix was significantly reduced relative to that observed in group PH. In the recovery phase, PBL and inflammatory cell infiltration were significantly reduced, and significantly greater collagen deposition was noted in group PP relative to groups PR and PH at 4 and 14 days after silk removal.

CONCLUSION

Chitosan-based, pH-responsive hydrogels loaded with PTB can retard the initiation of and facilitate the recovery from experimental periodontitis.

Controlled-release of tetracycline and lovastatin by poly(D,L-lactide-co-glycolide acid)-chitosan nanoparticles enhances periodontal regeneration in dogs

Chronic periodontitis is characterized by inflammation of periodontal tissues, leading to bone resorption and tooth loss. The goal of treatment is to regenerate periodontal tissues including bone and cementum lost as a consequence of disease. The local delivery of tetracycline was proven to be effective in controlling localized periodontal infection without apparent side effects. Previous studies suggested that lovastatin has a significant role in new bone formation; however, the local delivery of lovastatin might enhance its therapeutic effects. A number of local delivery devices have been developed recently, including poly(D,L-lactide-co-glycolide acid) (PLGA) nanoparticles. The aim of this study was to develop a local delivery device, PLGA-lovastatin-chitosan-tetracycline nanoparticles, which allows the sequential release of tetracycline and lovastatin to effectively control local infection and promote bone regeneration in periodontitis. The size and microstructure of nanoparticles were examined by transmission electron microscopy, Nanoparticle Size Analyzer, and Fourier transform infrared spectroscopy. The release of tetracycline and lovastatin was quantified using a UV-Vis spectrophotometer. Furthermore, the cytotoxic effect and alkaline phosphatase activity of the nanoparticles in osteoblast cell cultures as well as antibacterial activity against periodontal pathogens were investigated. Finally, the bone regeneration potential of PLGA nanoparticles in three-walled defects in beagle dogs was investigated. The results indicated that PLGA-lovastatin-chitosan-tetracycline nanoparticles showed good biocompatibility, antibacterial activity, and increased alkaline phosphatase activity. The volumetric analysis from micro-CT revealed significantly increased new bone formation in defects filled with nanoparticles in dogs. This novel local delivery device might be useful as an adjunctive treatment in periodontal regenerative therapy.

Targeted delivery as key for the success of small osteoinductive molecules

Molecules such as growth factors, peptides and small molecules can guide cellular behavior and are thus important for tissue engineering. They are rapidly emerging as promising compounds for the regeneration of tissues of the musculoskeletal system. Growth factors have disadvantages such as high cost, short half-life, supraphysiological amounts needed, etc. Therefore, small molecules may be an alternative. These molecules have been discovered using high throughput screening. Small osteoinductive molecules exhibit several advantages over growth factors owing to their small sizes, such as high stability and non-immunogenicity. These molecules may stimulate directly signaling pathways that are important for osteogenesis. However, systemic application doesn't induce osteogenesis in most cases. Therefore, local administration is needed. This may be achieved by using a bone graft material providing additional osteoconductive properties. These graft materials can also act by themselves as a delivery matrix for targeted and local delivery. Furthermore, vascularization is necessary in the process of osteogenesis. Many of the small molecules are also capable of promoting vascularization of the tissue to be regenerated. Thus, in this review, special attention is given to molecules that are capable of inducing both angiogenesis and osteogenesis simultaneously. Finally, more recent preclinical and clinical uses in bone regeneration of those molecules are described, highlighting the needs for the clinical translation of these promising compounds.

Simvastatin prodrug micelles target fracture and improve healing

Simvastatin (SIM), a widely used anti-lipidemic drug, has been identified as a bone anabolic agent. Its poor water solubility and the lack of distribution to the skeleton, however, have limited its application in the treatment of bone metabolic diseases. In this study, an amphiphilic macromolecular prodrug of SIM was designed and synthesized to overcome these limitations. The polyethylene glycol (PEG)-based prodrug can spontaneously self-assemble to form micelles. The use of SIM trimer as the prodrug's hydrophobic segment allows easy encapsulation of additional free SIM. The in vitro studies showed that SIM/SIM-mPEG micelles were internalized by MC3T3 cells via lysosomal trafficking and consistently induced expression of both BMP2 and DKK1 mRNA, suggesting that the prodrug micelle retains the biological functions of SIM. After systemic administration, optical imaging suggests that the micelles would passively target to bone fracture sites associated with hematoma and inflammation. Furthermore, flow cytometry study revealed that SIM/SIM-mPEG micelles had preferred cellular uptake by inflammatory and resident cells within the fracture callus tissue. The treatment study using a mouse osteotomy model validated the micelles' therapeutic efficacy in promoting bone fracture healing as demonstrated by micro-CT and histological analyses. Collectively, these data suggest that the macromolecular prodrug-based micelle formulation of SIM may have great potential for clinical management of impaired fracture healing.

Statins and alveolar bone resorption: a narrative review of preclinical and clinical studies

CONTEXT

Tooth extraction and periodontal disease are both common clinical situations associated with alveolar bone loss.

OBJECTIVE

To analyze the reported results of in vivo studies investigating the effectiveness of statins to reduce alveolar bone resorption.

STUDY DESIGN

Systematic electronic search of the MEDLINE-PubMed database.

RESULTS

A total of 21 studies met the inclusion criteria. This review showed that the use of statins reduced significantly alveolar bone resorption observed during periodontal disease and after tooth extraction. Oral administration was effective using high statin concentrations, although local administration using a biodegradable carrier was effective with lower concentrations. It was recently reported that statins were effective to reduce alveolar bone loss as an adjunct to scaling and root planing (SRP) in several clinical trials. Further studies are needed to confirm these promising results.

The role of topical simvastatin on bone regeneration: A systematic review

Objectives: The aim of this systematic review was to summarize the results concerning the use of simvastatin for promoting bone regeneration and to discuss the level of scientific evidence supporting such findings. Material and Methods: A Pubmed search using “Simvastatin”[Mesh] AND “Bone Regeneration”[Mesh] as Boolean operators was constrained to the last 10 years and only included papers written in English. Results: Of the 41 relevant papers reviewed, most of them (76.2%) have been published in the last 5 years, and most of them address animal studies (66.6%) performed on rats or rabbits in extraoral regions. Only 4 randomized controlled trials (RCTs) assessed the role of topical simvastatin in periodontal patients. Conclusions: A large part of the evidence concerning the role of topical simvastatin on bone regeneration comes from animal studies (mainly rats) focusing on extraoral bone defects. Only the use of subgingival simvastatin after root scaling has been properly supported by RCT.

Key words:Simvastatin, bone regeneration, topical administration, osteogenesis, osteoinduction.

Evaluation of anti-inflammatory effect of statins in chronic periodontitis

Objectives:

Statins are the group of lipid-lowering drugs commonly used to control cardiovascular and cerebrovascular diseases. Statins have potential anti-inflammatory effect by blocking the intermediate metabolites of the mevalonate pathway. The objective of this study was to evaluate the anti-inflammatory effect of statin medication in chronic periodontitis patients.

Materials and Methods:

Thirty patients of age group between 40 and 60 years were selected from the outpatient pool of Department of Periodontics, Thaimoogambigai Dental College and Hospital, Chennai. Thirty patients selected were grouped into two groups, Group-I consists of patients with generalized chronic periodontitis and on statin medication and Group-II consists of patients with generalized chronic periodontitis. Clinical parameters were recorded and gingival crevicular fluid (GCF) samples were analyzed for interleukin (IL)-1β using commercially available enzyme-linked immunosorbent assay.

Results:

The mean GCF IL-1β levels in generalized chronic periodontitis patients who are on statin medication (Group-I) were lower than the generalized chronic periodontitis patients without statin medication (Group-II).

Conclusion:

Reduction of GCF IL-1β levels in statin users indicate that statins have anti-inflammatory effect on periodontal disease.

Statins, bone metabolism and treatment of bone catabolic diseases

The discovery that statins had bone anabolic properties initiated many investigations into their use for treatment of bone catabolic diseases, such as osteoporosis. This paper reviews the molecular basis of statin's role in bone metabolism, and animal and human studies on the impact of systemic statins on osteoporosis-induced bone fracture incidence and healing, and on bone density. Limitations of systemic statins are described along with alternative dosing strategies, including local applications and bone-targeting systemic preparations. The principal findings of this review are: (1) traditional oral dosing with statins results in minimal efficacy in the treatment of osteoporosis; (2) local applications of statins show promise in the treatment of accessible bony defects, such as periodontitis; and (3) systemically administered statins which can target bone or inflammation near bone may be the safest and most effective strategy in the treatment of osseous deficiencies.

Tooth loss, periodontitis, and statins in a population-based follow-up study

BACKGROUND

Statins, frequently prescribed in lipid-lowering therapies, seem to have additional beneficial effects on periodontitis and tooth loss. If this is true, then chronic treatment with statins should also result in diminished tooth loss as a long-term response.

METHODS

A 5-year population-based follow-up study of tooth loss was performed comparing participants treated with statins (n = 134) with those not on the drugs (Study of Health in Pomerania). Negative binomial regression models were used to analyze the count variable of the outcome, including risk factors for tooth loss and measures of cholesterol metabolism.

RESULTS

When adjusted for age and sex, statins were associated with reduced tooth loss during the follow-up period (incidence risk ratio [IRR] = 0.70, 95% confidence interval [CI] = 0.50 to 0.99, P = 0.04). When additionally adjusted for risk factors of periodontal breakdown, IRR was 0.72 (95% CI = 0.52 to 1.01). There was significant interaction with low-density lipoprotein cholesterol (LDL-c) at baseline. After stratification by LDL-c, statins were associated with reduced tooth loss, resulting in IRR = 0.89 (95% CI = 0.44 to 1.83) and 0.64 (95% CI = 0.43 to 0.95), P = 0.03, at LDL-c concentrations ≤100 mg/dL and >100 mg/dL (2.58 mmol/L), respectively. The data also showed reduced tooth loss associated with the 5-year reduction in LDL-c levels on a mmol/L basis and independently of statins (IRR = 0.87, 95% CI = 0.80 to 0.96, P = 0.004).

CONCLUSION

Long-term treatment with systemically administered statins may have the beneficial effect of protecting against tooth loss.