Consensus Conference on Supra- and Subgingival Air Polishing

1. Supra- and subgingival air polishing using glycine powder is safe and effective for removal of biofilms from natural tooth structure and restorative materials;
2. there is no evidence of soft-tissue abrasion when using glycine powder in an air-polishing device;
3. in periodontal probing depths of 1 mm to 4 mm, glycine-powder air polishing, using a standard air-polishing nozzle, is more effective at removing subgingival biofilm than manual or ultrasonic instruments; and
4. at probing depths of 5 mm to 9 mm, using a subgingival nozzle, glycine powder air polishing is more effective at removing subgingival biofilm than manual or ultrasonic instrumentation. This conference statement, supported by an industry grant, was drafted by a panel of distinguished dental professionals.

A classic study by Axelsson et al¹ followed 257 adults for a 30-year period. The study initially enrolled 555 individuals, 180 allocated to a control group. Of the remaining 375 patients in the test group, 257 completed the 30-year study period. The study persuasively demonstrated the values of oral hygiene and periodontal maintenance therapy in the prevention of dental caries and long-term preservation of periodontal health. The calculated annual rates of tooth loss for the entire 30-year period were 0.01, 0.02, and 0.06 for the following age groups: 20 to 35 years, 36 to 50 years, and 51 to 65 years, respectively. Caries incidence was less than 2 surfaces per subject over the 30 years, and virtually no loss of clinical attachment level occurred.

It is generally accepted that the fundamental role of a periodic dental prophylaxis or an established periodontal maintenance program is to achieve stable oral health.^1-3 Depending on the level of risk for development of dental caries, periodontal disease, or disease recurrence, recommended recall intervals can vary considerably. The current standard of care suggests that patients at high risk for caries and/or at high risk for initial development or recurrent periodontal disease should be seen 3 to 4 times per year for evaluation and preventive care.^4,5 Indeed, shorter intervals may be required, eg, 4 to 6 times per year, for patients with aggressive disease, multiple risk factors, or a history of recurrent periodontitis.^4,5

Obviously, long-term preventive maintenance therapy will involve numerous sessions of tooth polishing, scaling, and possibly root planing. Such instrumentation, over time, can result in a cumulative loss of tooth structure, eg, enamel, cementum, or dentin.^6,7 Cleaning of teeth during a dental prophylaxis or a periodontal maintenance appointment generally involves manual or ultrasonic scaling, followed by polishing with a mild abrasive. Polishing of teeth using air-powder jet devices has become common practice as the procedure greatly facilitates the removal of tooth stains and supragingival calculus.⁸ However, studies on human or bovine teeth specimens have shown hard-tissue ablation defects of enamel and dentin, especially if traditional bicarbonate powders are delivered by an air-powder jet device.^9,10 As an alternative to the bicarbonate powders, glycine powders consisting of smaller and softer particles have been developed. Studies indicate that use of glycine powder results in satisfactory clinical and microbiologic outcomes and less abrasive effects on tooth structure, compared to the use of hand or ultrasonic scaling or air-powder jet devices using bicarbonate powder.^11-13

A consensus conference on the clinical relevance of the subgingival use of air polishing was held during the Europerio 7 Congress in 2012.¹⁴ The outcomes of the consensus conference were fully supportive of using glycine powders delivered by an air-powder device as part of the preventive treatment for biofilm-related dental diseases. However, despite such reports, questions persisted in the United States regarding safety and efficacy of using glycine powder as the active agent during air polishing of teeth. Consequently, a consensus conference was organized in the United States to evaluate and address issues of safety and efficacy when using glycine powder in an air-powder jet device for supra- and subgingival applications during dental prophylaxis and periodontal maintenance.

The consensus conference, with focus on dental air polishing, was supported by a grant from the Hu-Friedy Manufacturing Company, LLC. The conference was held on June 19, 2014 in Las Vegas, Nevada. Participants comprised an assembled panel of distinguished dental professionals, all with extensive knowledge and experience with dental air polishing as used for prophylaxis and periodontal maintenance therapy. Conference participants included: panel member and presenter Charles M. Cobb, DDS, MS, PhD; panel member and presenter Diane M. Daubert, RDH, MS; panel member Karen Davis, RDH; presenter Jodi Deming, RDH; moderator Thomas F. Flemmig, MBA, Dr. med. dent., Dr. med. dent. habil.; panel member Anna Pattison, RDH, MS; panel member Jean-François Roulet, DDS; and panel member Roger Vernon Stambaugh, DMD, MS.

The principal goal for the Consensus Conference was to use evidence-based scientific information to answer questions that have persisted in the dental community in the United States regarding the safety and efficacy of air polishing as used in dental prophylaxis and periodontal maintenance therapy.

Prior to the conference, all participants were asked to read a compilation of published studies consisting of peer-reviewed publications and randomized clinical-trial reports that followed the CONsolidated Standards of Reporting Trials 2010 guideline (CONSORT) statement.¹⁵ In addition, oral reports covering preassigned interest areas related to dental air polishing, based on existing published evidence were presented to the group. Areas of interest included:

• impact of air polishing on enamel, exposed root cementum and/or dentin and gingiva, and other oral mucosae;
• impact on restorative materials, eg, amalgam, composites, glass-ionomer and orthodontic bonding agents, and porcelain;
• efficacy of removal of supra- and subgingival microbial biofilms in both shallow and deep periodontal pockets; and
• overall safety and potential for adverse events.

Initially, it was confirmed that all panel members understood and were in complete agreement regarding the mechanics and physical principles of air polishing: “Air-polishing devices discharge a mixture of pressured air and abrasive particles. A water jet focuses the abrasive action and surrounds the centrally located air-particle jet. The abrasive effects of air-polishing devices depend on a number of factors, including abrasiveness of the particles (hardness, size, and shape), amount air pressure, water flow, nozzle configuration, and design features.” After reviewing the published peer-reviewed evidence base, the following consensus was reached by panel members:

The subject of sequencing the use of air polishing in those cases in which supra- and subgingival calculus is clinically evident was not discussed by the conference particpants. However, it is generally understood that air polishing is not an effective or efficient method for the removal of dental calculus. Thus, air polishing should be used on calculus-free surfaces or after existing calculus has been removed with the use of more aggressive types of instrumentation.^13,16,17

• The removal of biofilm and stain on intact tooth enamel using air polishing with sodium bicarbonate or glycine powders has been demonstrated to be safe.^18-20
• Air polishing with calcium carbonate, aluminum trihydroxide, or calcium sodium phosphosilicate powders can produce defects in enamel.²⁰

• The removal of biofilm on root cementum or root dentin using air polishing with glycine powder results in the least amount of root substance removal compared with other air- polishing powders.^10,11,21
• Air polishing with sodium bicarbonate, calcium carbonate, aluminum trihydroxide, or calcium sodium phosphosilicate powders may produce root-surface defects.^21,22

• Air polishing with glycine powder is safe for the removal of biofilms on the surface of gingiva and other oral mucosae.^13,16,23-24
• Air polishing with sodium bicarbonate has been shown to result in substantial gingival erosions when directed toward the gingiva.²³

• The removal of biofilm on amalgam, composite (including orthodontic bonding agents), glass ionomer, or porcelain restorative materials, air polishing with glycine powder results in the least amount of induced surface damage compared to other air-polishing powders.^18,20,26-28
• Air polishing with sodium bicarbonate, calcium carbonate, aluminum trihydroxide, or calcium sodium phosphosilicate powders can produce significant surface defects in restorations comprised of various materials.^20,26-28
• Air polishing with sodium bicarbonate on amalgam is safe.^18,20,29

• Supragingival Air Polishing
• Air polishing with sodium bicarbonate has been shown to be significantly more efficient in removing supragingival biofilm and stains compared to coronal polishing with rubber cup and pumice.¹⁸

• Clinical trials have evaluated the efficacy and safety of subgingival air polishing with glycine powder in shallow periodontal pockets (probing depth of ≤ 4 mm) in patients receiving periodontal maintenance therapy.^12,24,25
• In shallow periodontal pockets of ≤ 4 mm, subgingival air polishing with glycine powder directed into the periodontal pocket has been shown to be more efficacious in removing subgingival biofilm compared to scaling and root planing with hand instruments.^24,25 However, in terms of clinical parameters (bleeding on probing, probing depths, clinical attachment levels), treatments had no statistically significant differences.²⁵
• Clinical trials have shown that subgingival biofilm removal in shallow periodontal pockets by air polishing with glycine powder is safe.^12,16,24,25
• Patients perceived subgingival biofilm removal in shallow periodontal pockets by air polishing with glycine powder as more comfortable compared to subgingival instrumentation with hand instruments.^24,25
• In the last 16 years, only three isolated case reports showed air-polishing device was directly related to air emphysema.^30,31 As with any instrument that uses pressurized air (eg, high-speed handpiece, air-water syringe), the occurrence of an air emphysema is always a possibility.¹² However, given the rarity of published reports, the level of risk must be considered extremely rare.

• Clinical trials have evaluated the efficacy and safety of subgingival air polishing with glycine powder in deep periodontal pockets (probing depths of 5 mm to 9 mm) in patients receiving periodontal maintenance therapy.^13,24 Deep subgingival air polishing is safe only when performed with equipment that has a subgingival nozzle that attaches to the handpiece and pressure valves that have been appropriately set for subgingival air polishing.¹⁶
• In deep periodontal pockets, subgingival air polishing using a subgingival nozzle with glycine powder has been shown to be as efficacious or more efficacious in removing subgingival biofilm compared to subgingival root instrumentation using hand instruments or ultrasonic scalers.^13,24
• In terms of measurable clinical parameters, no statistically significant difference in the efficacy of subgingival air polishing, subgingival root instrumentation using hand instruments or ultrasonic scalers could be found.²⁴
• Biofilm debridement of all oral mucosae using air polishing with glycine powder resulted in a beneficial shift of the oral microbial composition.¹³
• Results from clinical trials show that subgingival biofilm removal in deep periodontal pockets by air polishing using a subgingival nozzle with glycine powder is safe.²⁴
• Results of clinical trials indicate that subgingival biofilm removal in deep periodontal pockets using air polishing with glycine powder is more efficient than that achieved by use of hand instruments or ultrasonic scalers.¹⁶
• Patients report that subgingival biofilm removal in deep periodontal pockets by air polishing with glycine powder is as comfortable or more comfortable than subgingival instrumentation with hand instruments or ultrasonic scalers.^13,16

One may question the utility of subgingival air polishing, as few studies used traditional periodontal parameters as outcome measures. Most studies were designed to test safety, efficiency, efficacy of removing subgingival biofilms at various probing depths, and impact on various oral tissue and biomaterials surfaces. Wennström et al¹⁷ reported subgingival air polishing resulted in a significant reduction in bleed on probing versus that achieved by ultrasonic instrumentation with a slim insert. In this same study,¹⁷ both methods of treatment resulted in statistically significant reductions in periodontal probing depth. However, given the superior patient comfort factor,^16,25 superior efficiency,¹⁶ and equivalent or superior reduction in subgingival microbial loads^{12,13,16,17,25} when compared to manual instrumentation, the value of air polishing in the private-practice settings appears to be clinically favorable and patient oriented.

Supra- and subgingival air polishing using glycine powder is safe and effective for removal of biofilms from natural tooth structure and restorative materials. Further, there is no evidence of soft-tissue abrasion when using glycine powder in an air-polishing device. The use of glycine-powder air polishing is more effective in removing subgingival biofilm than the utilization of manual or ultrasonic instruments in periodontal pockets up to 4-mm probing depths when used with a standard air polishing nozzle and in periodontal pockets of 5 mm to 9 mm of probing depth when used with a subgingival nozzle.

Charles M. Cobb, DDS, MS, PhD

Professor Emeritus

Department of Periodontics

School of Dentistry

University of Missouri-Kansas City

Diane M. Daubert, RDH, MS

Clinical Assistant Professor

Department of Periodontics

School of Dentistry

University of Washington

Karen Davis, RDH, BSDH

Private Practice

Dallas, Texas

Jodi Deming, RDH

Private Practice

Bellevue, Washington

Thomas F. Flemmig, Dr med dent, Dr med dent habil, MBA

Dean and Clinical Professor in Periodontology

Faculty of Dentistry

The University of Hong Kong

Anna Pattison, RDH, MS

Former Associate Professor

University of Southern California

Jean-François Roulet, DDS

Professor and Chair

Department of Restorative Dental Sciences,

University of Florida

Roger V. Stambaugh, DMD, MS

Private Practice

Burlington, WA

1. Axelsson P, Nyström B, Lindhe J. The long-term effect of a plaque control program on tooth mortality, caries and periodontal disease in adults. Results after 30 years of maintenance. J Clin Periodontol. 2004:31(9):749-757.

2. Hirschfeld L, Wasserman B. A long-term survey of tooth loss in 600 treated periodontal patients. J Periodontol. 1978:49(5):225-237.

3. Knowles JW, Burgett FG, Nissle RR, et al. Results of periodontal treatment related to pocket depth and attachment level. Eight years. J Periodontol. 1979;50(5):225-233.

4. Lang NP, Tonetti MS. Periodontal risk assessment (PRA) for patients in supportive periodontal therapy (SPT). Oral Health Prev Dent. 2003;1(1):7-16.

5. Axelsson P, Lindhe J. Effect of controlled oral hygiene procedures on caries and periodontal disease in adults. Results after 6 years. J Clin Periodontol. 1981;8(3):239-248.

6. Topoll HH, Lange DE, Horvath G. Profilometric and photomacroscopic studies of the surfaces of dental enamel, dentin, and root cementum after treatment with a powder-abrasion device (in German). Quintessenz. 1986;37(8):1397-1406.

7. Sahrmann P, Ronay V, Schmidlin PR, et al. Three-dimensional defect evaluation of air polishing on extracted human teeth. J Periodontol. 2014;85(8):1107-1114.

8. Berkstein S, Reiff RL, McKinney JF, Killoy WJ. Supragingival root surface removal during maintenance procedures utilizing an air-powder abrasive system or hand scaling. An in vitro study. J Periodontol. 1987;58(5):327-330.

9. Atkinson DR, Cobb CM, Killoy WJ. The effect of an air-powder abrasive system on in vitro root surfaces. J Periodontol. 1984;55(1):13-18.

10. Jost-Brinkmann PG. The influence of air polishers on tooth enamel. An in-vitro study. J Orofac Orthop. 1998;59(1):1-16.

11. Petersilka GJ, Bell M, Häeberlein I, et al. In vitro evaluation of novel low abrasive air polishing powders. J Clin Periodontol. 2003;30(1):9-13.

12. Flemmig TF, Hetzel M, Topoll H, et al. Subgingival debridement efficacy of glycine powder air polishing. J Periodontol. 2007;78(6):1002-1010.

13. Flemmig TF, Arushanov D, Daubert D, et al. Randomized controlled trial assessing efficacy and safety of glycine powder air polishing in moderate-to-deep periodontal pockets. J Periodontol. 2012;83(4):444-452.

14. Sculean A, Bastendorf KD, Becker C, et al. Paradigm shift in mechanical biofilm management? Subgingival air polishing: a new way to improve mechanical biofilm management in the dental practice. Quintessence Int. 2013;44(7):475-477.

15. CONSORT website. CONSORT 2010 checklist. https://www.consort-statement.org/checklists/view/32-consort/66-title. Accessed January 5, 2017.

16. Moëne R, Décaillet, Andersen E, Mombelli A. Subgingival plaque removal using a new air polishing device. J Periodontol. 2010;81(1):79-88.

17. Wennström JL, Dahlen G, Ramberg P. Subgingival debridement of periodontal pockets by air polishing in comparison with ultrasonic instrumentation during maintenance therapy. J Clin Periodontol. 2011;38(9):820-827.

18. Gutmann ME. Air polishing: a comprehensive review of the literature. J Dent Hyg. 1998;72(3):47-56.

19. Graumann SJ, Sensat ML, Stoltenberg JL. Air polishing: a review of current literature.

J Dent Hyg. 2013;87(4):173-180.

20. Barnes CM, Covey DA, Watanabe H, et al. An in vitro comparison of the effects of various air polishing powders on enamel and selected esthetic restorative materials. J Clin Dent. 2014;25(4):76-87.

21. Pelka M, Trautmann S, Petschelt A, Lohbauer U. Influ¬ence of air-polishing devices and abrasives on root dentin - an in vitro confocal laser scanning microscope study. Quintessence Int. 2010;41(7):e141-e148.

22. Petersilka GJ, Bell M, Mehl A, et al. Root defects following air polishing. An in vitro study on the effects of working parameters. J Clin Periodon¬tol. 2003;30(2):165-170.

23. Petersilka GJ, Faggion CM, Jr., Stratmann U, et al. Effect of glycine powder air-polishing on the gingiva. J Clin Periodontol. 2008;35(4):328-333.

24. Petersilka GJ, Steinmann D, Häeberlein I, et al. Subgingival plaque removal in buccal and lingual sites using a novel low abrasive air-polishing powder. J Clin Periodontol. 2003;30(4):328-333.

25. Petersilka GJ, Tunkel J, Barakos K, et al. Subgingival plaque removal at interdental sites using a low-abrasive air polishing powder. J Periodontol. 2003;74(3):307-311.

26. Pelka MA, Altmaier K, Petschelt A, Lohbauer U. The effect of air-polishing abrasives on wear of direct res¬toration materials and sealants. J Am Dent Assoc. 2010;141(1):63-70.

27. Engel S, Jost-Brinkmann PG, Spors CK, et al. Abrasive effect of air-pow¬der polishing on smooth surface sealants. J Orofac Orthop. 2009;70(5):363-370.

28. Giacomelli L, Salerno M, Derchi G, et al. Effect of air polishing with glycine and bicarbonate powders on nanocomposite used in dental restorations: an in vitro study. Int J Periodon¬t Restorative Dent. 2001;31(5):e51-e56.

29. Barnes CM, Hayes EF, Leinfelder KF. Effects of an air polishing system upon dental restorative materials. J Gen Dent. 1987;35(3):186-189.

30. Finlayson RS, Stevens FD. Subcutanmeous facial emphysema secondary to the use of the Cavi-Jet. J Periodontol. 1988;59(5):315-317.

31. Petersilka GJ. Subgingival air-polishing in the treatment of periodontal biofilm infections. Periodontol 2000. 2011;55(1):124-142.