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 Table of Contents  
Year : 2021  |  Volume : 33  |  Issue : 1  |  Page : 60-65

Efficacy of cryogun versus diode laser therapy in the management of oral leukoplakia

1 Department of Oral Medicine and Radiology, CKS Theja Dental College, Tirupathi, Andhra Pradesh, India
2 Clinical Practice, Department of Oral Medicine and Radiology, Ireland
3 Department of Oral Medicine and Radiology, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India
4 Department of Oral Medicine and Radiology, Sri Sai Dental College, Srikakulam, Andhra Pradesh, India

Date of Submission29-Jun-2020
Date of Decision11-Jan-2021
Date of Acceptance13-Jan-2021
Date of Web Publication26-Mar-2021

Correspondence Address:
Dr. K Naga Venkata Sai Praveen
Department of Oral Medicine and Radiology, CKS Theja Dental College, Tirupathi
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jiaomr.jiaomr_126_20

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Background and Aim: This study was aimed to clinically evaluate the effectiveness of 810 nm diode laser and cryosurgery in the management of oral leukoplakia (OL) in terms of healing outcomes. Materials and Methods: Thirty subjects clinically and histo-pathologically diagnosed as having OL were randomly allocated into two groups. Group-1 consisting of 15 subjects each treated with cryotherapy, Group-2 was treated with an 810 nm diode Laser. VAS scale was used for evaluating the postoperative discomfort due to pain and Bates- Jensen Wound Assessment Tool was used to evaluate clinical wound healing. Results: Data analysis was done by using one-way ANOVA for intragroup variations. For intergroup comparisons Paired t- test was used. A statistically significant number of recurrences was noticed in the cryo group compared to the LASER group. Conclusion: This study results suggest that both cryosurgery and laser therapy were effective in terms of patient comfort. However more number of recurrences and mild post operative edema in the cryo group make LASER therapy a better management option.

Keywords: Cryotherapy, Diode LASERs, oral leukoplakia, oral premalignant lesion

How to cite this article:
Sai Praveen K N, Veeraraghavan G, Ramesh T, Teja T N, Upendra G, Kalyan Y. Efficacy of cryogun versus diode laser therapy in the management of oral leukoplakia. J Indian Acad Oral Med Radiol 2021;33:60-5

How to cite this URL:
Sai Praveen K N, Veeraraghavan G, Ramesh T, Teja T N, Upendra G, Kalyan Y. Efficacy of cryogun versus diode laser therapy in the management of oral leukoplakia. J Indian Acad Oral Med Radiol [serial online] 2021 [cited 2021 Apr 14];33:60-5. Available from: https://www.jiaomr.in/text.asp?2021/33/1/60/312192

   Introduction Top

Oral cancer, mostly comprising of oral squamous cell carcinoma (OSCC), is the sixth most common cancer in the world with the etiology being multifactorial.[1] Although it is not known if OSCC can occur without premalignant changes in the tissues, at least 20% of OSCCs are documented arising in or associated with a clinically visible precursor lesion, such as oral leukoplakia (OL).[2] One of the new approaches for the control of this cancer is early detection of OL, which is considered to be the most common premalignant oral lesion and is represented in about 60% of patients diagnosed with OSCC.[1]

The term OL was first used by Schwimmer in 1877 to describe a white lesion of the tongue.[3] World health organization in the year 2005 has defined OL as “a white patch of questionable risk having excluded all other known disorders that carry no increased risk for cancer.”[4] Thus, OL is a clinical term used when any other white oral lesion has been excluded. OL is often associated with tobacco smoking, although idiopathic forms are not rare.[5]

Numerous protocols for the management of oral leukoplakia have been proposed which includes a conservative way of management such as Retinoids, antioxidants, and topical bleomycin along with surgical techniques such as scalpel excision, electrocoagulation, cryosurgery, and laser therapy. A consensus considered that surgery is the first choice in the management of OL.[6],[7]

LASER surgery

The word LASER is an acronym for Light Amplification by the Stimulated Emission of Radiation. Lasers are devices that produce intense beams of light that are monochromatic, coherent, and highly collimated. The rate of temperature rise plays a vital role in this effect. Diode lasers – also known as low-level lasers possessing penetration depth of 2 to 3 mm into the tissues (depending on wavelength), causes less damage to the surrounding tissues and are being commonly used in treating oral lesions. Moreover, it has the advantages of a compact and portable design.[8]

Cryosurgery- is controlled and targeted destruction of diseased tissue by the application of cold temperature using a cryogen. It is a simple, cost-effective, efficient, and aesthetically acceptable modality. It is being used in Oral medicine for over 30 years. Several cryogens such as liquid nitrogen, nitrous oxide, carbon dioxide are made available for this technique. Cryosurgery has advantages like the reasonably predictable volume of tissue destruction, with relatively less pain, safe, easy to perform, and inexpensive procedure with less patient discomfort.[9]

Both cryosurgery and laser surgery have added advantages like selective removal of the affected epithelium, minimal damage to surrounding healthy tissue along with minimal postoperative pain, edema, and scarring.[8],[9] The existing literature has shown the individual effectiveness of the modalities in managing OL. Very few studies have shown the comparison and efficacy in the management of oral leukoplakia. On this basis, this study was undertaken to elicit the effectiveness of cryosurgery and laser therapy in the management of oral leukoplakia.

   Materials and Methods Top

A total of 30 subjects attending the outpatient department of Dental College, Bhimavaram for routine dental treatment, who were clinically and histopathologically diagnosed as having OL were included in the present longitudinal comparative clinical study. The study was conducted after taking clearance from the Institutional Review Board (Institutional Ethical Number: VDC/IEC/2014-21; Date: 22-1-2014). Among these, subjects diagnosed with systemic diseases, that can interfere with healing were excluded from the study.

Sample size estimation


L = allowable error = 20% of P = 16.8

P = prevalence = 84

q = 100-P = 16

z = 1.96

Substituting the values in formula,

With aforementioned calculations, sample size determined is 18 in number. But considering nonresponsive errors/drop out, final sample size derived is 30 in number.

All the subjects (diagnosed cases of oral leukoplakia) enrolled were explained about the purpose of this study in the local vernacular language. Written informed consent was obtained from each subject for the intervention to be conducted on them following Helsinki's declaration. Details of general information, any relevant past dental and medical history were recorded in a specially designed proforma. Patients were counselled to quit tobacco and alcohol habits before treatment. They were randomly allocated into two groups, each group comprising of 15 subjects.

Cryosurgery was performed with a gas expansion cryoprobe using nitrous oxide gas after applying topical anesthetic gel [Figure 1]. The lesion was frozen for 10 seconds and thawed immediately, and this cycle was repeated two times [Figure 2]. For the laser application, a Fotona XD-2 810 nm diode laser was employed [Figure 3]. Both the operator and patient were insisted to put on protective eyewear for safety concerns [Figure 4]. Ablation of the lesion was done in contact mode, and care was taken not to produce excessive charring.
Figure 1: Apparatus Used For Performing Cryosurgery

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Figure 2: Patient Undergoing Cryosurgery

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Figure 3: Fotona Xd-2 810 nm Diode Laser

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Figure 4: Patient Undergoing Laser Therapy

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Patients were asked to apply ice packs and an anesthetic mouth wash was also prescribed for 1 week to prevent discomfort at the operated site. All the cases were examined on the first, second, and third successive weeks postoperatively and were recalled for every month for 2 months. Evaluation of postoperative discomfort was done by using a visual analog scale (VAS)[2] scoring while Bates-Jensen Wound Assessment Tool[10] was used to evaluate clinical wound healing [Figure 5] and [Figure 6].
Figure 5: (a) Pre Operative Treatment Photograph of Cryo Group. (b) Postoperative Treatment Photograph

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Figure 6: (a) Pre operative treatment photograph of laser Group. (b) Postoperative treatment photograph

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Statistical analysis

Data analysis was done using a one-way ANOVA test for intragroup variations. For intergroup comparisons, Paired t-test was used. A Chi-square test was performed to know the significance of recurrences in both the study groups. Results with a P < 0.05 were considered significant.

   Results Top

In this study, a one-way ANOVA test was performed to know the postoperative pain in, cryo and LASER group subjects during first, second, third week, second and third month follow-up periods. The results showed a significant decrease in the postoperative pain scores with P = 0.01 for the cryo group and 0.05 for the laser group [Table 1]. In this study, complete healing of the treated site was noticed by the end of the third week and second month follow-up period in cryo and laser groups, respectively [Table 2].
Table 1: Post-Operative pain in laser and cryo group at different time intervals

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Table 2: Wound healing scores in cryo and laser group at different time intervals

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Paired t-test was used to compare the postoperative pain scores at different time intervals between both the groups. The results revealed a significant difference in postoperative pain scores between the cryo group and the laser group in the first week (P = 0.027) with a mean value of 1.00 in the cryo group and 1.53 in the laser group and P value significant at the level of 0.05. This infers that there was comparatively less discomfort due to postoperative pain in the cryo group than in the laser group. By the end of the third week, there was a complete reduction in postoperative pain (with a score of 0) in both cryo and laser groups. A similar observation was found even during second and third- month follow-up [Graph 1].

A significant difference in wound healing scores between the cryo group and the laser group subjects was noticed in the first, second, third week, second month with a P value of 0.003 in the first week and 0.001 in successive weeks with an insignificant difference during third-month follow-up with a P value of 0.082 was noticed [Graph 2].

A Chi-square test was performed to know the significance of recurrences in both the study groups. Of the total 15 subjects in both the groups a total of 4 cases (26.7%) and 1 case (6.7%) of recurrence was noticed by the end of the third month in cryo and Laser groups respectively. A statistically significant number of recurrences were noticed in the cryo group (p-value: 0.021) by the end of this third-month follow-up [Graph 3].

   Discussion Top

Oral cancer often begins as potentially malignant disorders that can be best characterized as lesions in which there is a risk for uncontrolled cellular growth and transformation into cancer, followed by the disruption of normal functioning tissues.[11],[12] Oral leukoplakia forms part of a set of potentially malignant disorders.[13]

It has been reported that dysplastic OL carries a 5-fold greater risk of malignant transformation than non-dysplastic OL. This malignant potential of OL highlights the importance of early detection and prompt treatment of this lesion.[13] In this study, patients were selected based on the histopathological dysplastic features of the lesion similar to studies conducted by Ishii et al.[14] and Chuan-Hang Yu et al.[15]

Various non-surgical and surgical modalities have been reported in the management of oral leukoplakia but, currently, there is no consensus on which is the best. This could be attributed to the fact that the outcome seems to vary and long-term follow-up studies are very few. Management of OL is primarily directed towards the elimination of possible causative factors, like tobacco and alcohol usage, followed by other modalities.[16] According to Kundoor et al.[17] non-surgical means of management failed to prevent malignant transformation and achieve recurrence-free treatment.

Surgical management include conventional surgery, electrocoagulation, cryosurgery, and laser surgery (excision or evaporation). Most of the time, the treatment of OL is always directed towards the patient's comfort. Both Cryosurgery and Laser therapy have advantages like the reasonably predictable volume of tissue destruction, with relatively less pain, safe, easy to perform, and inexpensive technique with less patient discomfort.[14],[18] Till date there are very few studies regarding the comparison of diode laser (810 nm) and cryosurgery in the management of OL.

When the postoperative pain was analyzed based on findings, all the subjects of cryo group reported mild pain at the first-week follow-up which regressed completely by their third week. This goes by the observations of Narula et al.[19] Mild pain usually exists in subjects treated with cryotherapy because of the deposition of cellular degradation products that affect the peripheral nerves adjacent to the site of therapy.[18]

Postoperative pain was reduced completely within a short duration of 1 week in the study conducted by Chuan-Hang Yu et al. (2009)[15] which is not by this study. This may be probably due to differences in the cryogen used, size of the lesion, and mode of treatment.[18]

When postoperative pain was analyzed among the laser group, all the 15 subjects reported mild postoperative pain during the first week follow-up period which also subsided completely by the end of the third week. This is in agreement with studies conducted by studies of Pick et al.,[20] Pecaro et al.,[21] and Frame.[22] The probable reason might be peripheral nerve fiber exposure during the healing process.[22]

Observations of Raval et al.[8] has shown a reduction of postoperative pain by the end of the first week which is dissimilar to our study. This may be due to the difference in the power of Laser used.[6]

In a comparison of postoperative pain in both the study groups significant difference was observed at first-week follow-up with less postoperative pain noticed in the Cryo group than in the Laser group. This is attributed to the fact that in cryosurgery depth of freezing is variable (i.e., majority of the times superficial depth) depending on the factors such as pressure on the mucosa, length of freezing, and vascularity of tissues, whereas the depth of penetration in laser therapy is fixed which is about 2 to 3 mm and is deeper to a certain extent when compared to cryosurgery.[8],[23]

Out of 15 subjects treated with cryotherapy, healing was completed by the end of the third week in all the subjects. These study results are similar to observations of Narula et al.[19] Chuan-Hang Yu et al.[15] reported complete healing within 2 weeks which is not per this study. This could be due to a difference in the number of sessions used for the cryotherapy procedure.[24]

Healing was completed by the second month in all the subjects treated using an 810 nm Diode Laser. These observations are following the studies of Akbulut et al.[25] and Kapoor et al.[26] Observations of Kundoor et al.,[17] and Sarkar et al.[6] has shown complete regression of treated site by the end of the third week.

In a comparison of postoperative healing in both the study groups significant difference was observed at first, second, third week and second-month follow-up with less duration for healing noticed in the Cryo group than Laser group. As described elsewhere, the depth of penetration plays a key role in postoperative healing. In cryo group where the depth of penetration is very low and superficial will result in less damage and consequently results in faster healing.[23]

On comparison rate of recurrence in both, the study groups revealed a significant number of recurrences noticed in the Cryo group than in the Laser group which was not per the findings of Varun Kumar et al.[27] This could be best explained as the depth of freezing achieved by the application of cryotherapy varies from 2 mm to several centimeters.

Limitations and future prospects

Limitations of cryotherapy include lack of precision in the procedure, making it difficult to judge the final volume of tissue necrosis. Disadvantages of LASER surgery include prolonged healing time and ocular damage of the operator if not used with appropriate eyewear. Inadequate destruction of lesions and continuation of tobacco usage habit results in a higher rate of recurrence. Due to this, future studies should monitor smoking cessation and a much more extended follow-up period to attain better results.[24],[28]

   Conclusion Top

Treatment with cryosurgery has advantages like the selective removal of the affected epithelium and minimal damage to surrounding healthy tissue, resulting in excellent wound healing with no or minimal scar tissue and a good functional result. Similarly, laser surgery also has its advantages in that it results in minimal postoperative edema, pain, inflammation, and scarring. Thus, both of these treatment modalities can be tried as an alternative to conventional treatment. Nevertheless owing to the patient's comfort, laser therapy is quite advantageous over cryosurgery.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

   References Top

Warnakulasuriya S. Global epidemiology of oral and oropharyngeal cancer. Oral Oncol 2009;45:309-16.  Back to cited text no. 1
Greenberg MS, Glick M, Ship JA. Text Book of Burket's Oral Medicine. 11th ed.. BC Decken Ontario, Canada 2008.  Back to cited text no. 2
Neville BW, Day TA. Oral cancer and precancerous lesions. CA Cancer J Clin 2002;52:195-215.  Back to cited text no. 3
Lima JS, Pinto DS Jr, Sousa SOM, Correa L. Oral leukoplakia manifests differently in smokers and non-smokers. Braz Oral Res 2012;26:543-9.  Back to cited text no. 4
Axell T. Occurrence of leukoplakia and some other oral white lesions among 20,333 adult Swedish people. Community Dent Oral Epidemiol 1987;15:46-51.  Back to cited text no. 5
Sarkar S, Kailasam S, Iyer VH: Effectiveness of Diode Laser and Er, Cr: YSGG Laser in the Treatment of Oral Leukoplakia - A Comparative Study. Dentistry 2015;5:274.  Back to cited text no. 6
Kumar A, Cascarini L, McCaul JA, Kerawala CJ, Coombes D, Godden D, et al. How should we manage oral leukoplakia? Br J Oral Maxillofac Surg 2013;51:377-83.  Back to cited text no. 7
Raval N, Raju DR, Athota A, Reddy TY. Diode laser and white lesions: A clinical study on postoperative recovery, depth control and wound healing. J Indian Acad Oral Med Radiol 2011;23:S308-11.  Back to cited text no. 8
Valappila Nidhin J, Ganapathi KS, Sweta S. Cryosurgery as a treatment modality in Leukoplakia-A pilot study. UJMDS. 2013;1:31-4.  Back to cited text no. 9
Harris C, Bates-Jensen B, Parslow N, Raizman R, Singh M, Ketchen R. Bates-Jensen wound assessment tool: Pictorial guide validation project. J Wound Ostomy Continence Nurs 2010;37:253-9.  Back to cited text no. 10
Feller LL, Khammissa RR, Kramer BB, Lemmer JJ. Oral squamous cell carcinoma in relation to field precancerisation: Pathobiology. Cancer Cell Int 2013;13:31.  Back to cited text no. 11
Martorell-Calatayud A, Botella-Estrada R, Bagán-Sebastián JV, Sanmartín-Jiménez O, Guillén-Barona C. Oral leukoplakia: Clinical, histopathologic, and molecular features and therapeutic approach. Actas Dermosifiliogr 2009;100:669-84.  Back to cited text no. 12
Warnakulasuriya S, Johnson NW, van der Waal I. Nomenclature and classification of potentially malignant disorders of the oral mucosa. J Oral Pathol Med 2007;36:575-80.  Back to cited text no. 13
Ishii J, Fujita K, Munemoto S, Komori T. Management of oral leukoplakia by laser surgery: Relation between recurrence and malignant transformation and clinicopathological features. J Clin Laser Med Surg 2004;22:27-33.  Back to cited text no. 14
Yu CH, Chen HM, Chang CC, Hung HY, Hsiao CK, Chiang CP. Cotton-swab cryotherapy for oral leukoplakia. Head Neck 2009;31:983-8.  Back to cited text no. 15
Lodi G, Sardella A, Bez C, Demarosi F, Carrassi A. Systematic review of randomized trials for the treatment of oral leukoplakia. J Dent Educ 2002;66:896-902.  Back to cited text no. 16
Reddy Kundoor VK, Patimeedi A, Roohi S, Maloth KN, Kesidi S, Masabattula GK. Efficacy of diode laser for the management of potentially malignant disorders. J Lasers Med Sci 2015;6:120-3.  Back to cited text no. 17
Amanat D, Ebrahimi H, Zahedani MZ, Zeini N, Pourshahidi S, Ranjbar Z. Comparing the effects of cryotherapy with nitrous oxide gas versus topical corticosteroids in the treatment of oral lichen planus. Indian J Dent Res 2014;25:711-6.  Back to cited text no. 18
[PUBMED]  [Full text]  
Narula R, Malik B. Role of cryosurgery in the management of benign and premalignant lesions of the maxillofacial region. Indian J Dent Sci 2012;4:63-6.  Back to cited text no. 19
Pick RM, Pecaro BC. Use of the CO2 laser in soft tissue dental surgery. Lasers Surg Med 1987;7:207-13.  Back to cited text no. 20
Pecaro BC, Garehime WJ. The CO2 laser in oral and maxillofacial surgery. J Oral Maxillofac Surg 1983;41:725-8.  Back to cited text no. 21
Frame JW. Removal of oral soft tissue pathology with the CO2 laser. J Oral Maxillofac Surg 1985;43:850-5.  Back to cited text no. 22
Sako K, Marchetta FC, Hayes RL. Cryotherapy of intraoral leukoplakia. Am J Surg 1972;124:482-4.  Back to cited text no. 23
Prasad M, Kale TP, Halli R, Kotrashetti SM, Baliga SD. Liquid nitrogen cryotherapy in the management of oral lesions: A retrospective clinical study. J Maxillofac Oral Surg 2009;8:40-2.  Back to cited text no. 24
Akbulut N, Kursun ES, Tumer MK, Kamburoglu K, Gulsen U. Is the 810-nm diode laser the best choice in oral soft tissue therapy? Eur J Dent 2013;7:207-11.  Back to cited text no. 25
  [Full text]  
Kapoor D, Kapoor V, Garg S, Gill S. Diode laser as a treatment option for leukoplakia tongue: A case report. Indian J Dent Sci 2014;6:62-3.  Back to cited text no. 26
Kumar V, Malhotra D, Mular AG, Sachan S, Sharma D. Cryosurgery for the treatment of oral leukoplakia: Satisfying or not? Indian J Dent Sci 2017;9:256-60.  Back to cited text no. 27
  [Full text]  
Natekar M, Raghuveer HP, Rayapati DK, Shobha ES, Prashanth NT, Rangan V, et al. A comparative evaluation: Oral leukoplakia surgical management using diode laser, CO2 laser, and cryosurgery. J Clin Exp Dent 2017;9:e779-84.  Back to cited text no. 28


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  [Table 1], [Table 2]


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