CASE SERIES

Use of a Carbon Dioxide Laser as an Adjunct to Scaling and RootPlaning for Clinical New Attachment: A Case Series

Jeffrey D. Pope,* Jeffrey A. Rossmann,* David G. Kerns,* M. Miles Beach,* and Daisha J. Cipher†

Introduction: Severe, chronic periodontitis (CP) is typically treated either with scaling and root planing (SRP) orsurgical therapy in an effort to gain clinical attachment. The advantage of non-surgical therapy is decreased morbidityto the patient; however, the site typically heals by formation of a long junctional epithelium. The advantage of surgicaltherapy is access for debridement and the use of bone or bone substitutes in combination with a barrier membranefor epithelial exclusion. Compared with a non-surgical approach, surgical therapy is more invasive, and patient accep-tance of treatment is typically more challenging. The use of lasers in dentistry appears to be rapidly increasing, as evi-denced by the influx of new lasers into the dental market as well as numerous anecdotal reports of beneficial results withtheir use.

Case Series:This report presents a novel approach to the treatment of severeCPusing a carbon dioxide (CO2) laser incombination with SRP. This study presents the findings of 17 patients (nine males and eight females, aged 34 to 71 years;mean age: 54 years) that were compared in a split-mouth design and followed for 3 months. To the best of the authors’knowledge, this is the first reported case series using a CO2 laser for de-epithelialization in combination with SRP for thetreatment of CP.

Conclusion:Sites treatedwith theCO2 laser tended to showa greater decrease in probing depths, greater amounts ofrecession, and greater gains in clinical attachment levels, but the results were not statistically significantly better than SRPalone. Clin Adv Periodontics 2014;4:209-215.

Key Words: Case reports; dental scaling; lasers; periodontitis; regeneration; root planing.

BackgroundThe primary goal of scaling and root planing (SRP) orsurgical therapy for the treatment of periodontal diseaseis the formation of new clinical attachment. SRP is notexpected to influence new bone formation to any greatdegree but hopefully would lead to healing with a connec-tive tissue (CT) attachment rather than a long junction-al epithelium.1 Predominant human histologic evidence

demonstrates healing by a long junctional epitheliumwith no or minimal CT attachment.2

Often clinicians treat intrabony defects with guided tis-sue regeneration (GTR) in which the operator reflects full-thickness mucoperiosteal flaps, debrides the defect, graftswith bone or a bone substitute, and covers the graft with abarrier membrane.3 The concept of GTR is to selectively al-low cells from the bone, CT, and periodontal ligament torepopulate the root surface before epithelial cells contactthe healing site.

Lasers have been used extensively in the dental field sincetheir inception and were first applied in vivo to humanteeth in 1965.4 Rossmann et al.5-8 showed the carbon diox-ide (CO2) laser will effectively remove gingival epitheliumwithout causing damage to the underlying CT. A controlledclinical trial byCentty et al.9 evaluated patientswith contra-lateral defects in a split-mouth design. The results of that

* Department of Periodontics, Texas A&M Health Science Center, BaylorCollege of Dentistry, Dallas, TX.

† Department of Biostatistics and Research, University of Texas Arlington,Arlington, TX.

Submitted May 16, 2012; accepted for publication March 26, 2013

doi: 10.1902/cap.2013.120061

Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 209

study also verified the CO2 laser can de-epithelialize com-pletely the inner and outer aspect of a mucoperiosteal flapwhile leaving the underlying CT undisturbed.

In an attempt to use the concepts of GTR in a non-surgical protocol, this case series presents a novel approachto periodontal treatment with the adjunctive use of a CO2

laser. This series is a prospective, split-mouth design thatevaluates the clinical outcome of using a CO2 laser de-epithelialization technique to block epithelial down-growth in conjunction with SRP (test sites) versus SRPalone (control sites) for the treatment of severe, chronicperiodontitis (CP).

Clinical Presentation and CaseManagementThis case series consisted of 17 patients (nine males andeight females, aged 34 to 71 years; mean age: 54 years)and was conducted from February 2011 to April 2012.Study participants were required to have a minimum oftwo contralaterally similar periodontal probing depths(PDs) ‡5 mm with clinical attachment loss (AL) ‡4 mmon two or more posterior teeth (Fig. 1). Recession (REC),bleeding on probing (BOP), furcation (FUR) involvement,and mobility (MOB) were also recorded. There were 92posterior teeth with 252 qualifying sites that were includedin the study.A customacrylic stentwas used for reproduciblemeasurements, and one periodontal probe‡ was used for allexaminations. Oral hygiene instructions were given at theinitial evaluation and reinforced at every patient visit. Ap-proval for research was granted by the Institutional ReviewBoard at Texas A&MHealth Science Center, Baylor Collegeof Dentistry, Dallas, Texas. All participants signed a writteninformed consent document before treatment.

Patients were subjected to SRP under local anesthesia.All SRP was performed by one of the authors (JDP). Soft-tissue curettage was inadvertently performed during thescaling procedure. No direct attempt was made to removethe sulcular epithelium by directing the instruments towardthe soft-tissue wall. Immediately after SRP, the patient’s leftor right side was randomly assigned to the test or controlgroup using a random allocation table. The control sidedid not receive any additional treatment. The test sidewas treated using a CO2 laser set at 8-Wpulsedmode usinga 0.8-mm spot size to deliver an energy density ofz150 to250 mJ/cm2. This power setting has been shown histolog-ically to effectively remove epithelium without damagingthe underlying CT.5-8 The buccal and lingual gingival epi-thelium was completely removed around the test teeth toa level z5 mm apical to the gingival margin (Fig. 2). Carewas taken to avoid using the CO2 laser on hard tissue ormucosa; the laser tip was not introduced into the peri-odontal pocket. Patients were given 0.12% chlorhexidinegluconate at the initial visit with instructions to use themouthrinse twice daily for the first 4 weeks after SRP. Thepatients returned at 10, 20, and 30 days after scaling foradditional laser de-epithelialization (at a similar or reducedsetting) to the test side in an effort to block epithelial

downgrowth on the root surface, using a previously pub-lished protocol (Fig. 3).10 This was performed under localanesthesia as needed for patient comfort. Patients were in-structed to take 400 mg ibuprofen every 4 to 6 hours asneeded for discomfort. Patients were evaluated 3 monthsafter scaling (Fig. 4). Clinical measurements were takenat baseline by the primary examiner (JDP) and one addi-tional periodontist (JAR or DGK). Final measurementswere taken by a masked examiner (MMB).

Clinical OutcomesMethods of Statistical AnalysisThe unit of analysis for this case series was the patient,with teeth nested within patients. Mean – SDs were calcu-lated for the continuous clinical measurements and n (per-centage) for binary measurements (Table 1). Linear mixedmodels were constructed to compare the two procedureson changes over time in PDs, REC, clinical attachmentlevels (CALs), and BOP. The fixed-effects portion of eachmodel was “procedure” (CO2 laser in combination withSRP versus SRP alone), and the random-effects portionof each model was the patient, with teeth nested withineach patient. “Time” was specified as the repeated effect,with two levels (baseline and 3 months after surgery) witha first-order autoregressive covariance structure. Subse-quently, data collected frommaxillarymolars,maxillarypre-molars, mandibular molars, and mandibular premolars wereanalyzed separately. First, linear mixed models were com-puted within each of the four categories to compare the

FIGURE 1 Test site at baseline. 1a Facial view, CP present. 1b Palatal view.

‡ UNC-15 probe, Hu-Friedy, Chicago, IL.

C A S E S E R I E S

210 Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 Laser De-Epithelialization With Non-Surgical Therapy

two procedures on changes over time in PDs, REC, CAL,and BOP. Main effects for procedure and time were tested(exactly as described above). Second, linear mixed modelswere computed between each of the four categories tocompare each category with one another. Main effectsfor time and “category” were tested.

Analyses of Whole SampleThe linear mixed model for PDs indicated that there wasno significant effect for procedure: F(1,15.7) ¼ 1.04, P ¼0.32. However, all sites significantly improved over time:F(1,20.5) ¼ 53.3, P <0.0001. PDs averaged 6.1 – 1.5 mm atbaseline and improved to 4.1 – 1.4 mm at 3 months for thetest sites. For the control sites, PDs averaged 6.0 – 1.2 mmat baseline and improved to 4.5 – 1.7 mm at 3 months.In summary, all sites exhibited improvement regardless ofthe procedure received (Table 1).

The linearmixedmodel forREC indicated that therewasno significant effect for procedure: F(1,226.5) ¼ 0.45, P ¼0.50. REC levels averaged 0.2 – 1.3 mm at baseline and

1.0 – 1.2 mm at 3 months for the test sites. For the controlsites, REC levels averaged 0.1 – 1.3 mm at baseline and0.8 – 1.5 mm at 3 months. All patients showed increasedamounts of REC regardless of the procedure received(Table 1).

The linear mixed model for CALs indicated that therewas no significant effect for procedure: F(1,22) ¼ 0.07,P ¼ 0.80. However, all sites significantly improved overtime: F(1,11.3) ¼ 32.7, P <0.0001. CALs averaged 6.3 –1.8mmatbaseline and improved to5.0–2.0mmat3monthsfor the test sites. For the control sites, CALs averaged 6.1 –2.0mmatbaselineand improved to5.3–2.6mmat3months.Therefore, all patients showed improved CALs regardlessof the procedure received (Table 1).

The linearmixedmodel for BOP indicated that therewasno significant effect for procedure: F(1,15.1) ¼ 0.51, P ¼0.49. However, all patients significantly improved overtime: F(1,25.7) ¼ 34.1, P <0.0001. BOP at baseline was94.9% and improved to 52.5% at 3 months for the testsites. For the control sites, BOP was 94.4% at baseline

FIGURE 2 CO2 laser de-epithelialization of thetest site at baseline. 2a Facial view showinglaser handpiece ablating epithelial layer withcarbonization of tissue present. 2b Extent ofde-epithelialization and removal of carbonizationlayer to check for epithelial remnants. 2c Facialview after completion of de-epithelialization andplacement of carbonized layer as a sealant. 2dPalatal view after completion of de-epithelializationprotocol.

FIGURE 3 Test site 10 days after laser de-epithelialization. 3a Facial view showing partialre-epithelialization. 3b Palatal wound. 3c Reap-plication of de-epithelialization protocol, facialview. 3d Palatal view after de-epithelialization.

C A S E S E R I E S

Pope, Rossmann, Kerns, Beach, Cipher Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 211

and improved to 56.8% at 3 months. Therefore, all pa-tients showed a reduction in BOP regardless of the proce-dure received (Table 1).

Overall, sites treated with the CO2 laser had a slightlygreater reduction in PDs, greater amounts of REC, andslightly greater CAL gains than sites treated by SRP alone.

Analyses of Data Within and Among SpecificTooth SitesAs shown in Table 2, linear mixed models computed withineach of the four categories (maxillary molars, maxillary pre-molars, mandibular molars, and mandibular premolars) tocompare the two procedures on changes over time revealedthat PDs decreased over time within each category. With theexception of maxillary premolars, CAL improved over time.REC did not significantly differ within any of the four sub-categories over time (P >0.10). BOP decreased over timewithin each category. Finally, none of the outcomes signifi-cantly differed by procedure within any of the categories(P >0.15).

As shown in Table 2, linear mixed models computed be-tween each of the four categories to compare each categorywith one another revealed three statistically significantdifferences. Mandibular premolar PDs andRECwere signif-icantly lower at follow-up than themaxillary premolars (P¼0.038 and P¼ 0.03, respectively). Mandibular molar BOPFIGURE 4 Test site at 3 months. 4a Facial view. 4b Palatal view.

TABLE 1 Clinical Outcomes for Analysis of Whole Sample

Measurements PD REC CAL BOP

Baseline

Test sites 6.1 0.2 6.3 95%

Control sites 6.0 0.1 6.1 94%

Whole sample 6.1 0.2 6.2 95%

Baseline to 3 months

Test sites �2.0 0.8 1.3 �42%

Control sites �1.5 0.7 0.8 �37%

Whole sample �1.8 0.7 1.0 �40%

3 months

Test sites 4.1 1.0 5.0 53%

Control sites 4.5 0.8 5.3 57%

Whole sample 4.3 0.9 5.2 55%

P ¼ 0.32 P ¼ 0.50 P ¼ 0.80 P ¼ 0.49

All values are in millimeters, except BOP, which is a percentage of sites involved. Baseline to 3 months values represent the amount of increase (positive numbers) ordecrease (negative numbers) in each parameter.

C A S E S E R I E S

212 Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 Laser De-Epithelialization With Non-Surgical Therapy

values were significantly lower than maxillary molars atfollow-up (P ¼ 0.03). No other significant comparisonsemerged.

No site-specific data analysis was performed for FURinvolvement, MOB, vertical defects, or mucogingivaldefects. All data were analyzed as mean – SD data forcomparative analysis. The authors did not note anyobservational differences among groups for how thetest and control sites responded to these parameters.

DiscussionIn this case series, a novel approach was used in an attemptto apply the concepts of GTR in a non-surgical manner forthe treatment of severe CP. Within the confines of this caseseries, the adjunctive use of CO2 laser de-epithelializationwas not clinically or statistically significantly better thanSRP alone for the treatment of severe CP in selectedposterior teeth.

It is possible that plaque control was a factor in the out-come of this study as seen in Figure 4. A plaque index wasnever recorded at any time period. By having the patientsreturn every 2 to 3 weeks for plaque control and prophy-laxis, the outcome of this study may have been different.

Yukna et al.1 reported on inserting the laser tip of aneodymium:yttrium-aluminum-garnet laser into the sulcusso that the laser irradiates the sulcular epithelium and rootsurface. In the current case series, the CO2 laser is only usedon the outer gingival epithelium, and only posterior teethwere studied. This could be another reason the resultsof this case series are not in agreement with other authorsthat report positive gains from laser therapy inside thesulcus. Additionally, a study by Crespi et al.11 used aCO2 laser in a defocused mode for root conditioning and de-epithelializationof the innerwall of the gingival flap and founda significant improvement in CAL over a 15-year follow-upwhen compared with modified Widman flap surgery.

TABLE 2 Clinical Analysis of Patient Data According to Tooth Site

Baseline 3 Months

Tooth Site PD REC CAL PD REC CAL

Maxillary molars

Test 6.20 – 1.13 0.44 – 1.18 6.64 – 1.75 4.58 – 1.52 0.98 – 1.37 5.56 – 2.32

Control 6.38 – 1.43 0.54 – 1.48 6.91 – 2.52 5.32 – 1.86 1.05 – 1.89 6.38 – 3.23

Total 6.29 – 1.29 0.49 – 1.33 6.77 – 2.16 4.95 – 1.73 1.02 – 1.65 5.97 – 2.83

Maxillary premolars

Test 5.56 – 0.51 0.04 – 1.21 5.60 – 1.41 4.00 – 1.41 0.92 – 1.41 4.92 – 1.82

Control 5.53 – 0.70 �0.28 – 0.85 5.25 – 1.05 3.75 – 1.05 0.42 – 1.18 4.17 – 1.61

Total 5.54 – 0.62 �0.15 – 1.01 5.39 – 1.21 3.85 – 1.21 0.62 – 1.29 4.48 – 1.73

Mandibular molars

Test 6.46 – 2.46 0.04 – 1.53 6.50 – 2.06 3.54 – 1.04 0.82 – 0.77 4.36 – 1.28

Control 5.77 – 0.92 �0.09 – 1.02 5.68 – 1.39 4.18 – 1.22 0.55 – 0.51 4.73 – 1.55

Total 6.16 – 1.95 �0.02 – 1.32 6.14 – 1.83 3.82 – 1.16 0.70 – 0.68 4.52 – 1.40

Mandibular premolars

Test 6.00 – 1.15 �0.20 – 1.03 5.80 – 1.48 3.10 – 0.57 1.30 – 0.67 4.40 – 1.07

Control 6.09 – 1.14 �0.36 – 1.29 5.73 – 1.10 3.45 – 0.93 1.00 – 0.77 4.45 – 1.37

Total 6.05 – 1.12 �0.29 – 1.15 5.76 – 1.26 3.29 – 0.78 1.14 – 0.73 4.43 – 1.21

Total (all sites)

Test 6.11 – 1.50 0.20 – 1.27 6.31 – 1.78 4.08 – 1.42 0.96 – 1.21 5.04 – 1.98

Control 6.00 – 1.20 0.11 – 1.28 6.11 – 2.02 4.50 – 1.66 0.78 – 1.47 5.28 – 2.64

Total 6.05 – 1.35 0.16 – 1.27 6.21 – 1.91 4.30 – 1.56 0.86 – 1.35 5.16 – 2.34

Data are presented as mean – SD. All values are in millimeters.

C A S E S E R I E S

Pope, Rossmann, Kerns, Beach, Cipher Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 213

The non-surgical results from this case series are in agree-ment with other non-surgical studies. Kaldahl et al.12 re-ported a 1.23-mm reduction in PD (0.96-mm gain in CAL)for sites with initial PDs from 5.0 to 6.0 mm at 3 months.These same authors also saw a PD reduction of 2.18 mm(1.66-mm gain in CAL) in sites ‡7.0 mm. Cobb13 reportedthat, in pockets that initially measured 4 to 6 mm, the meanreduction in PDwas 1.29mmwith a net gain in CAL of 0.55mm. Periodontal pockets ‡7.0 mm showed a mean reduc-tion in PD of 2.16 mm and a gain in CAL of 1.19 mm. In

the current study, when the authors combine the test andcontrol sites, there is a 1.8-mm reduction in probing (1.0-mm CAL gain) for all sites with PDs ‡5.0 mm at 3 months.Additional research is needed to evaluate the efficacy of CO2

laser therapy in combinationwith non-surgical therapy. Forfuture studies, the authors recommend establishing the pa-tient’s plaque control and possibly irradiating the sulcusand/or root surface using a defocused mode. A larger sam-ple size would confirm any trends noted with the adjunctiveuse of a CO2 laser in combination with SRP. n

Summary

Why are these cases newinformation?

j To the best of the authors’ knowledge, this is the first reported caseseries using a CO2 laser for de-epithelialization in combination withSRP for the treatment of CP.

What are the keys to successfulmanagement of these cases?

j Good compliance, frequent periodontal recall visits, and adequateplaque control are crucial to the success of any type of periodontaltherapy.

j Definitive root debridement for the removal of biofilm and subgingivalcalculus is essential for obtaining new attachment.

What are the primary limitations tosuccess in these cases?

j Compliance with recall visits and adequate plaque control areimportant in the maintenance of CALs.

j Access to deeper PDs and FUR involvement are critical elements fornon-surgical therapy in molar areas.

j Multiple treatment visits during the first month of therapy are required.

AcknowledgmentsThe authors thank the following people for their contribu-tions to the preparation and completion of this case series:Dr.Emet Schneiderman,Department ofBiomedical Sciences,Baylor College of Dentistry, Texas A&M Health ScienceCenter, Dallas, Texas, and Dr. Terry Rees, Ms. Jan Steele,Ms. Carla Thomas, Ms. Karen Fuentes, and Ms. AngelaLee-Noles, all from Department of Periodontics, TexasA&M Health Science Center, Baylor College of Dentistry.The authors report no conflicts of interest related to thiscase series.

CORRESPONDENCE:Dr. Jeffrey A. Rossmann, Department of Periodontics, Texas A&M HealthScience Center, Baylor College of Dentistry, 3302 Gaston Ave., Dallas, TX75246. E-mail: JRossmann@bcd.tamhsc.edu.

C A S E S E R I E S

214 Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 Laser De-Epithelialization With Non-Surgical Therapy

References1. Yukna RA, Carr RL, Evans GH. Histologic evaluation of an Nd:YAG

laser-assisted new attachment procedure in humans. Int J PeriodonticsRestorative Dent 2007;27:577-587.

2. Cobb CM. Non-surgical pocket therapy: Mechanical. Ann Periodontol1996;1:443-490.

3. Gottlow J, Nyman S, Lindhe J, Karring T, Wennstrom J. Newattachment formation in the human periodontium by guided tissueregeneration. Case reports. J Clin Periodontol 1986;13:604-616.

4. Goldman L, Gray JA, Goldman J, Goldman B, Meyer R. Effect of laserimpacts on teeth. J Am Dent Assoc 1965;70:601-606.

5. Rossmann JA, Gottlieb S, Koudelka BM, McQuade MJ. Effects of CO2

laser irradiation on gingiva. J Periodontol 1987;58:423-425.

6. Rossmann JA, McQuade MJ, Turunen DE. Retardation of epithelialmigration in monkeys using a carbon dioxide laser: An animal study.J Periodontol 1992;63:902-907.

7. Rossmann JA, Cobb CM. Lasers in periodontal therapy. Periodontol2000 1995;9:150-164.

8. Rossmann J; Research, Science and Therapy Committee of theAmerican Academy of Periodontology. Lasers in periodontics. J Peri-odontol 2002;73:1231-1239.

9. Centty IG, Blank LW, Levy BA, Romberg E, Barnes DM. Carbondioxide laser for de-epithelialization of periodontal flaps. J Periodontol1997;68:763-769.

10. Israel M, Rossmann JA, Froum SJ. Use of the carbon dioxide laser inretarding epithelial migration: A pilot histological human study utilizingcase reports. J Periodontol 1995;66:197-204.

11. Crespi R, Cappare P, Gherlone E, Romanos GE. Comparison ofmodified Widman and coronally advanced flap surgery combined withCO2 laser root irradiation in periodontal therapy: A 15-year follow-up.Int J Periodontics Restorative Dent 2011;31:641-651.

12. Kaldahl WB, Kalkwarf KL, Patil KD, Dyer JK, Bates RE Jr. Evaluationof four modalities of periodontal therapy. Mean probing depth, probingattachment level and recession changes. J Periodontol 1988;59:783-793.

13. Cobb CM. Clinical significance of non-surgical periodontal therapy: Anevidence-based perspective of scaling and root planing. J Clin Peri-odontol 2002;29(Suppl. 2):6-16.

indicates key references.

C A S E S E R I E S

Pope, Rossmann, Kerns, Beach, Cipher Clinical Advances in Periodontics, Vol. 4, No. 4, November 2014 215