Indian Journal of Dental Research

ORIGINAL RESEARCH
Year
: 2015  |  Volume : 26  |  Issue : 4  |  Page : 384--389

The clinical efficacy of laser assisted modified Widman flap: A randomized split mouth clinical trial


Pundir J Aena1, Agrawal Parul1, Pundir Siddharth2, Goyal Pravesh1, Diwan Vikas1, Agrawal Vandita1,  
1 Department of Periodontics, Rungta College of Dental Science and Research, Bhilai, Chhattisgarh, India
2 Department of Oral Pathology, Rungta College of Dental Science and Research, Bhilai, Chhattisgarh, India

Correspondence Address:
Pundir J Aena
Department of Periodontics, Rungta College of Dental Science and Research, Bhilai, Chhattisgarh
India

Abstract

Objective: The objective of the study was to compare the clinical efficacy of use of a diode laser (DL) (810 nm) as an adjunct to modified Widman flap (MWF) surgery to that of MWF alone. Materials and Methods: Twenty-five patients between the ages of 20 and 50 years with generalized chronic periodontitis were selected for the study. Control sites (Group A) were randomly selected to receive an MWF, and the contralateral test sites (Group B) received MWF in conjunction with low-level laser therapy. The energy density of 4 J/cm 2 was applied to the gingival surface after periodontal treatment. The study tooth/site was treated along with any additional teeth in the quadrant in which the site was located if needed. Randomization was done using a coin flip. The DL was used to de-epithelialize the inner part of the periodontal flap and photo-biostimulate the surgical area. Plaque index (PI), papillary bleeding index (PBI), probing depth (PD), and clinical attachment level (CAL) scores were recorded at baseline and at 6 and 9 months. Statistical Analysis: Data were expressed as the mean ± standard deviation. Statistical analyzes were performed using paired Student's t-testfor intragroup comparisons and unpaired Student's t-test for intergroup comparisons.Results: No significant difference was observed in PI scores between the two groups at baseline, 6 and 9 months. PBI scores were significantly lower in Group B versus Group A at 6 months (P < 0.01). However, no significant difference was observed between the two groups in PBI scores at the end of 9 months. PD reduction in Group B versus Group A was statistically significant at the end of 9 months (P < 0.01). Gains in CAL were significantly greater in Group B versus Group A at 6 and 9 months. Conclusion: The use of an 810 nm DL provided additional benefits to MWF surgery in terms of clinical parameters.



How to cite this article:
Aena PJ, Parul A, Siddharth P, Pravesh G, Vikas D, Vandita A. The clinical efficacy of laser assisted modified Widman flap: A randomized split mouth clinical trial.Indian J Dent Res 2015;26:384-389


How to cite this URL:
Aena PJ, Parul A, Siddharth P, Pravesh G, Vikas D, Vandita A. The clinical efficacy of laser assisted modified Widman flap: A randomized split mouth clinical trial. Indian J Dent Res [serial online] 2015 [cited 2019 Aug 24 ];26:384-389
Available from: http://www.ijdr.in/text.asp?2015/26/4/384/167626


Full Text



Periodontitis is a chronic inflammatory disease that affects the supporting structures of teeth, resulting in tooth loss. It is mainly initiated by plaque-biofilm and characterized by bacteria-induced inflammation which leads to the destruction of tooth-supporting structures and alveolar bone. A major objective of periodontal therapy is to remove the soft and hard, supra- and sub-gingival deposits from the root surface to stop disease progression.[1] Mechanical scaling and root debridement have shown to be an effective treatment approach for periodontal disease.[2] The surgical procedure involving treatment of periodontal pockets by modified Widman flap (MWF) approach mainly aims at reattachment and readaptation of the pocket walls rather than the surgical eradication of the outer walls of the pockets.[3] In recent years, various innovative adjunctive treatments have been developed to improve the clinical effectiveness of scaling and root debridement.[4]

Among the various new technologies offered, therapeutic laser treatment, also referred to as low-level laser therapy (LLLT), offers numerous benefits. Along with the primary benefit of being nonsurgical, it promotes tissue healing and reduces edema, inflammation, and pain.[5] The use of LLLT as a therapeutic agent was first investigated by Mester et al.,[6] who found that it improved wound healing in rats. It is suggested that LLLT alters cellular behaviour by affecting the mitochondrial respiratory chain or membrane calcium channels, and thus facilitates collagen synthesis, angiogenesis, and growth factor release, which eventually accelerate wound healing.[7] Laser-enhanced biostimulation has been reported to induce the intracellular metabolic changes, resulting in faster cell division, proliferation rate, migration of fibroblasts, and rapid matrix production. It has also been found to promote fibroblast maturation and proliferation, macrophage phagocytosis and lymphocyte activation.[8] Recently LLLT has been used in the field of dentistry as an adjunct to nonsurgical periodontal treatment.[9] However, the use of LLLT has still not been widely accepted by the medical and dental community due to the lack of a sufficient number of controlled clinical trials.

Thus, the purpose of this study was to evaluate and compare the long-term clinical outcomes of diode laser (DL) assisted MWF surgery versus conventional treatment with the MWF procedure.

 Materials and Methods



After receiving the approval from the Institutional Ethical Committee, 25 patients (12 women, 13 men) between the ages of 20 and 50 years were selected for the study from the outpatient Department of Periodontics. A detailed case history proforma was designed and details of all the patients were recorded. The verbal and written consent was obtained from all the patients after explaining the complete clinical procedure. All the patients were nonsmokers. The patients who reported long-term steroidal or antibiotic therapy, systemic diseases likely to affect wound healing or pregnancy were excluded. Three patients dropped out after the first surgical procedure because they could not keep subsequent appointments. The study was conducted from August 2012 to November 2013.

Clinical parameters

Baseline measurements including plaque index (PI), papillary bleeding index (PBI), probing pocket depth (PPD), and clinical attachment level (CAL) were recorded. Each patient had two contralateral periodontal pockets. To qualify for this study, patients had to have, in two contralateral quadrants, at least the same posterior or anterior tooth with one site, each with a probing depth (PD) ≥7 mm, clinical attachment loss ≥7 mm [Figure 1], and a gingival index ≥1.[10]{Figure 1}

This study was a randomized single-masked split mouth clinical study. The patient did not know which site received laser (810 nm) therapy. One clinician enrolled, evaluated and treated all the patients. All the patients received a hygienic treatment phase consisting of oral hygiene instructions, supragingival prophylaxis, and non surgical procedure comprising of thorough sub gingival scaling and root planing ≥6 weeks before surgical treatment. At the baseline visit, the contralateral surgical sites were randomly assigned to control or test by a coin flip. After the hygienic treatment, phase A periodontal charting was made. Any teeth, with pockets equal to or deeper than 5 mm that were present in the same quadrant as the study teeth, were surgically treated. The test sites received MWF using active DL inside the flap [Figure 2]a while the control sites received MWF alone [Figure 2]b. The time interval between the two surgeries was 3 weeks. In all sites, the MWF was followed by the elimination of granulation tissue using hand instruments, ultrasonics and rotary instruments [Figure 3]a and [Figure 3]b. Thorough root planning was done on all root surfaces with curettes. In one control quadrant and in one test quadrant in two different patients, minor osteoplasty was performed.{Figure 2}{Figure 3}

A 810 nm aiming beam was used to remove all visible epithelium in the inner side of the flap from the free gingival margin to the bottom of the apical aspect of the flap (both labial and lingual/palatal). The tip was initiated with the use of articulating paper. The treatment was performed from the coronal to the apical aspect of parallel paths, and the laser emission was interrupted for 30 s if the irradiation exceeded 10 s. The resultant char layer was totally removed with moist gauze before replacing the flaps [Figure 4]. Care was taken to avoid any laser contact to the root surface or the alveolar bone by placing a periosteal retractor between the hard and soft tissue and aiming the laser (810 nm) beam at a 45° angle to the soft-tissue flap. A second laser application with the same laser in continuous mode at 0.1 W was made. All surfaces of the flap, inner and outer, exposed bone, and exposed root structures involved in the surgery were irradiated, leading to a total dosage of 4 J/cm 2 per surface. The MFW was sutured [Figure 5] with an interrupted suture using 4-0 black silk suture in all patients. The power output of the laser was assessed throughout the duration of the study using a hand-held meter provided with the unit.{Figure 4}{Figure 5}

Postsurgical care consisted of 0.2% chlorhexidine rinse twice a day for 14 days. Sutures were removed at 7 days postsurgery. Follow-up appointments were scheduled at monthly intervals of 3, 6, and 9 months. All clinical parameters were again measured at 6 and 9 months postsurgery [Figure 6].{Figure 6}

Statistical analysis

Data were expressed as the mean ± standard deviation. Differences in PI, PBI, PPD, and CAL scores between baseline, 6 and 9 months were analyzed with the paired Student's t-test for intragroup comparisons and unpaired Student's t-test for intergroup comparisons. The individual patient was included as a random effect in all mixed effects regression models since each patient gave more than one tooth. Statistical significance was set at P < 0.01 – significant and P < 0.001 – highly significant.

 Results



Twenty-two subjects (n = 22 in each group) completed the 9-month follow-up period. No statistically significant differences were found in the mean values for the PI between the test and control groups at baseline (P = 0.173), 6 months (P = 0.729), and 9 months (P = 0.801). At 6 months, the mean difference in PBI scores between the test and control groups was 0.018 which was statistically significant (P < 0.01). However, no significant difference was observed between the two groups in PBI scores at the end of 9 months. No statistically significant differences were found in PD between the test and control groups at baseline (P = 0.646) and 6 months (P = 0.109). However, there was the highly significant difference between test and control groups at 9 months (P = 0.014). The decrease in PD in the test group from baseline to 6 months was 64.26% as compared to the control group which showed a decrease of 54.52%. Again, there was statistically significant difference between test and control groups in CAL at 6 (P = 0.036) and 9 months (P < 0.001). This gain in CAL from the baseline to 6 months postoperatively was 81.84% for the test group and 67.93% for the control group as shown in [Table 1]. The changes in CAL at baseline, 6 and 9 months are presented in [Figure 7]. The differences in P values in PI, PBI, PD and CAL in test and control groups at 6 and 9 months are presented in [Figure 8].{Table 1}{Figure 7}{Figure 8}

 Discussion



The present study indicated that the use of the DL as an adjunct to the surgical treatment of deep periodontal pockets resulted in statistically significant reductions in PD and CAL gain at the end of 9 months posttreatment.

Results obtained in the present study with conventional MWF surgery, that is, reduction in PD and gain in CAL, confirm those reported by other investigators. For example, Lindhe et al.[11] reported a PD reduction of 3.4 mm ± 0.8 mm and CAL gain of 1.5 mm ± 0.6 mm after open flap debridement on nonmolar teeth with initial PD >6 mm. Similarly, Pihlstrom et al.[12] showed a significant PD reduction of 3.4 mm and CAL gain of 1.19 mm, and Isidor and Karring [13] reported PD reduction of 2.5 mm ± 0.4 mm and CAL gain of only 0.2 mm ± 0.3 mm after periodontal surgical treatment. In our study, MWF surgery resulted in immediate PD reduction and CAL gain, which is in line with the findings of Pihlstrom et al.[12] for deeper pockets (>6 mm).

There are presently five peer-reviewed published clinical trials using a DL wavelength. Two of these are an investigation of the effects of LLLT on the gingival inflammatory response in human experimental gingivitis model.[14],[15] One study reported significant effects on clinical parameters that favored the DL wavelength.[16] Important factors in the effectiveness of LLLT include dose, wavelength and the amount of energy applied.[17] The dose applied during laser application is the most important treatment parameters in the usage of LLLT. However, a precisely determined dose has not been proved for each indication. Biostimulation has been reported in the literature with doses between 0.001 J/cm 2 and 10 J/cm 2 as a therapeutic window.[18] Even though applied dose is in the therapeutic window range, it might be too low or too high for the desired effect. Mester et al.[6] suggested in 1971 that doses of ≈1–2 J/cm 2 are necessary to see an effect on wound healing. In our study we used a DL with a wavelength of 810 nm, the output power of 0.5–7 W, leading to a total dosage of 4 J/cm 2 energy density on each surface after treatment. This dose has also been proved to enhance the epithelialization and wound healing by previous studies after gingivectomy and gingivoplasty.[19],[20]

In the present study, addition of DL to conventional MWF surgery resulted in greater reduction in PD and greater gain in CAL compared to MWF surgery alone. The reduction in PD and the gain in CAL were significantly greater in the laser group from 6 to 9 months. No further differences in any of the observed clinical parameters were found after 9 months. This improvement could be a result of an increase in the anti-inflammatory cytokine levels and an increase of microcirculation by the low-level laser irradiation.[21]

The mechanism of LLLT involves photoreceptors in the electron transport chain within the membrane of cell mitochondria. Absorption of light creates a short-term activation of respiratory chain components, promoting ATP production and activation of nucleic acid synthesis.[22] LLLT has an additional effect on fibroblasts by promoting proliferation and increasing cell numbers, secretion of growth factors, and differentiation of fibroblasts into myofibroblasts.[23],[24]

During wound healing the inflammatory response and synthesis of specific extracellular matrix molecules by fibroblasts; angiogenesis, reepithelialization and remodeling are regulated by growth factors including transforming growth factor-beta1 (TGF-β1) and basic fibroblast growth factor (bFGF).[25] TGF-β1 plays an important role in wound healing by stimulating fibroblast proliferation, increasing the synthesis of extracellular matrix molecules and inhibitors of matrix metalloproteinases (MMPs), and inhibiting MMP synthesis.[26] bFGF is a potent mitogen and chemo attractant for fibroblasts and endothelial cells and induces a predominantly angiogenic response in the wound and activates the neutral proteases in both epithelial cells and fibroblasts.[27] Variousin vitro studies have shown that laser irradiation increases bFGF release from gingival fibroblasts.[28] This collectively results in improved wound contraction and accelerated wound healing.[29],[30]

 Conclusion



Despite a large number of publications concerning the application of lasers in periodontics, there still are relatively few longitudinal clinical trials. This, in turn, has led to a persistent disagreement among the clinicians regarding the appropriate application of lasers to the treatment of chronic periodontitis. The present study demonstrated that LLLT application as an adjunct to MWF yielded greater PD reduction and CAL gain as compared to the conventional treatment. Further studies are required to assess the long-term effectiveness of biostimulation with LLLT as an adjunct in the treatment of periodontitis.

Acknowledgement

My sincere acknowledgement to the staff and students of Department of Periodontics, Rungta College of Dental Science and Research, Bhilai, Chhattisgarh, India.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Cobb CM. Non-surgical pocket therapy: Mechanical. Ann Periodontol 1996;1:443-90.
2Morrison EC, Ramfjord SP, Hill RW. Short-term effects of initial, nonsurgical periodontal treatment (hygienic phase). J Clin Periodontol 1980;7:199-211.
3Ramfjord SP, Nissle RR. The modified Widman flap. J Periodontol 1974;45:601-7.
4Sanz M, Teughels W; Group A of European Workshop on Periodontology. Innovations in non-surgical periodontal therapy: Consensus Report of the Sixth European Workshop on Periodontology. J Clin Periodontol 2008;35 8 Suppl: 3-7.
5Sun G, Tunér J. Low-level laser therapy in dentistry. Dent Clin North Am 2004;48:1061-76, viii.
6Mester E, Spiry T, Szende B, Tota JG. Effect of laser rays on wound healing. Am J Surg 1971;122:532-5.
7Marques MM, Pereira AN, Fujihara NA, Nogueira FN, Eduardo CP. Effect of low-power laser irradiation on protein synthesis and ultrastructure of human gingival fibroblasts. Lasers Surg Med 2004;34:260-5.
8Walsh LJ. The current status of low level laser therapy in dentistry. Part 1. Soft tissue applications. Aust Dent J 1997;42:247-54.
9Kreisler M, Al Haj H, d'Hoedt B. Clinical efficacy of semiconductor laser application as an adjunct to conventional scaling and root planing. Lasers Surg Med 2005;37:350-5.
10Löe H. The gingival index, the plaque index and the retention index systems. J Periodontol 1967;38:610-6.
11Lindhe J, Westfelt E, Nyman S, Socransky SS, Heijl L, Bratthall G. Healing following surgical/non-surgical treatment of periodontal disease. A clinical study. J Clin Periodontol 1982;9:115-28.
12Pihlstrom BL, Oliphant TH, McHugh RB. Molar and nonmolar teeth compared over 6 1/2 years following two methods of periodontal therapy. J Periodontol 1984;55:499-504.
13Isidor F, Karring T. Long-term effect of surgical and non-surgical periodontal treatment. A 5-year clinical study. J Periodontal Res 1986;21:462-72.
14Magnusson I, Runstad L, Nyman S, Lindhe J. A long junctional epithelium – A locus minoris resistentiae in plaque infection? J Clin Periodontol 1983;10:333-40.
15Noguchi T, Sanaoka A, Fukuda M, Suzuki S, Aoki T. Combined effects of Nd:YAG laser irradiation with local antibiotics applications into periodontal pockets. J Clin Periodontol 2005;32:670-6.
16Finkbeiner RL. The results of 1328 periodontal pockets treated with the argon laser: Selective pocket thermolysis. J Clin Laser Med Surg 1995;13:273-81.
17Khadra M, Kasem N, Lyngstadaas SP, Haanaes HR, Mustafa K. Laser therapy accelerates initial attachment and subsequent behaviour of human oral fibroblasts cultured on titanium implant material. A scanning electron microscope and histomorphometric analysis. Clin Oral Implants Res 2005;16:168-75.
18Tuner J, Hode L. Some Basic Laser Physics. 2nd ed. Grangesberg (Sweden): Prima Books; 2007. p. 317-38.
19Lagan KM, Clements BA, McDonough S, Baxter GD. Low intensity laser therapy (830nm) in the management of minor postsurgical wounds: A controlled clinical study. Lasers Surg Med 2001;28:27-32.
20Ozcelik O, Cenk Haytac M, Kunin A, Seydaoglu G. Improved wound healing by low-level laser irradiation after gingivectomy operations: A controlled clinical pilot study. J Clin Periodontol 2008;35:250-4.
21Woodruff LD, Bounkeo JM, Brannon WM, Dawes KS, Barham CD, Waddell DL, et al. The efficacy of laser therapy in wound repair: A meta-analysis of the literature. Photomed Laser Surg 2004;22:241-7.
22Yu W, Naim JO, Lanzafame RJ. The effect of laser irradiation on the release of bFGF from 3T3 fibroblasts. Photochem Photobiol 1994;59:167-70.
23Kreisler M, Christoffers AB, Al-Haj H, Willershausen B, d'Hoedt B. Low level 809-nm diode laser-inducedin vitro stimulation of the proliferation of human gingival fibroblasts. Lasers Surg Med 2002;30:365-9.
24Pereira AN, Eduardo Cde P, Matson E, Marques MM. Effect of low-power laser irradiation on cell growth and procollagen synthesis of cultured fibroblasts. Lasers Surg Med 2002;31:263-7.
25Aukhil I. Biology of wound healing. Periodontol 2000 2000;22:44-50.
26Roberts AB, Sporn MB. The Molecular and Cellular Biology of Wound Repair. 2nd ed. New York: Plenum Publishers; 1996. p. 275-308.
27Cochran DL, Wozney JM. Biological mediators for periodontal regeneration. Periodontol 2000 1999;19:40-58.
28Saygun I, Karacay S, Serdar M, Ural AU, Sencimen M, Kurtis B. Effects of laser irradiation on the release of basic fibroblast growth factor (bFGF), insulin like growth factor-1 (IGF-1), and receptor of IGF-1 (IGFBP3) from gingival fibroblasts. Lasers Med Sci 2008;23:211-5.
29Medrado AR, Pugliese LS, Reis SR, Andrade ZA. Influence of low level laser therapy on wound healing and its biological action upon myofibroblasts. Lasers Surg Med 2003;32:239-44.
30Walsh LJ. The current status of laser applications in dentistry. Aust Dent J 2003;48:146-55.