26 January 2023

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Effects of local simvastatin in periodontal maintenance treatment

Lara Figini

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Object of the study

Periodontal maintenance therapy (PMT) includes the removal of bacterial plaque and calculus from the supragingival and subgingival areas through mechanical and selective root planing treatment RP. 

Several literature studies have found that patients undergoing regular PMT show a lower incidence of periodontal problems and keep their teeth longer than those who do not follow a regular periodontal maintenance protocol. To treat residual pockets that are inflamed or progressing during PMT, adjunctive therapies have been developed to further reduce bacterial burden, inflammation, PD pocket depth and improve clinical attachment levels (CAL). 

Additional therapies for traditional PMT include the local administration of anti-inflammatories or growth factors, and simvastatin. Simvastatin (SIM) is a specific competitive inhibitor of 3-hydroxy-2-methylglutaryl coenzyme A reductase. It was originally developed to reduce serum cholesterol but has been shown to also have anti-inflammatory and bone anabolic properties. 

The application of statins, as demonstrated by various human clinical studies during initial periodontal therapy, can reduce the PD of the periodontal pocket, reduce clinical attachment loss and reduce inflammation. However, further research is needed to investigate the effects of SIM when applied to residual pockets in patients who have already undergone initial therapy and are receiving PMT.

Type of research and methods of analysis

In a double-blind, randomized, controlled study published in the Journal of Periodontology in July 2022, the authors investigated whether local application of SIM, in combination with minimally invasive treatment of papilla reversal and planing (PR/RP), may be effective for improving the clinical attachment level (CAL), for reducing probing depth (PD) and for obtaining an increase in interproximal bone height (IBH) in patients undergoing PMT with persistent periodontal pockets of 6-9 mm. 

Fifty patients with stage III and grade B periodontitis with interproximal PD of 6-9 mm and bleeding on probing (BOP) were included in the study. Patients were randomly assigned to the experimental group [PR/RP+SIM/methylcellulose (MCL); n = 27] or control group (PR/RP+MCL; n = 23). 

The root surfaces were accessed via reflection of interproximal papillae, followed by RP 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

Results obtained at the baseline time and at 12 months respectively for the PR/RP+SIM/MCL and PR/RP+MCL treatments: CAL: -1.9 ± 0.3 mm, p < 0.0001; -1.0 ± 0.3mm, 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). PR/RP+SIM/MCL had greater improvements for CAL (p = 0.03), PD (p = 0.007), and BOP (p = 0.047).

Conclusions

From the data of this study, the researchers concluded that the addition of SIM/MCL to PR/RP improved CAL, PD and BOP, compared with PR/RP alone in periodontal maintenance patients.

Clinical implications

Dentists should take into consideration that the addition of local simvastatin can significantly improve periodontal parameters and can be useful as a support in periodontal maintenance therapies. However, further research should be conducted on the anti-inflammatory and antimicrobial effects of SIM, and on the long-term clinical effects.

Amy C. Killeen, Lauren E. Krell, Mattie Bertels, Mary M. Christiansen, Laura Anderson, Robin L. Hattervig, Kaeli K. Samson, Dong Wang, Richard A. Reinhardt. “Effect of locally applied simvastatin on clinical attachment level and alveolar bone in periodontal maintenance patients: A randomized clinical trial.” J Periodontol. 2022 Nov; 93(11):1682-1690. doi: 10.1002/JPER.21-0708. Epub 2022 Jul 12.