EFFICACY OF DIODE LASER IN THE MANAGEMENT OF ORAL LICHEN PLANUS:A SYSTEMATIC REVIEW

Mai Abdel Fattah 1 and Ahmed Salah 2 . 1. B.D.S., M.Sc. Assistant lecturer, Oral Medicine, Oral Diagnosis and Periodontology Department, Faculty of Dentistry, MSA University, 6th October, Egypt. 2. MBBCH, M.S. Anaesthesia, Faculty of Medicine, Cairo University, Egypt. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History


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(cyclosporine, tacrolimus, and pimecrolimus), phototherapy, CO2 laser and recently, diode laser. The most common treatment of OLP involves the use of topical steroids; steroids are effective in the treatment of OLP because of their anti-inflammatory effect and anti-immunologic properties of suppressing T-cell function (Radfar et al., 2008). Prolonged using of corticosteroids cause adverse effects such as candidiasis, dry mouth, bad taste, nausea, sore throat, and, uncommon moon face, and inhibition of the hypothalamus-pituitary-adrenal axis (Thongprasom and Dhanuthai, 2008).
"Recently, there has been much interest and controversy regarding the use of laser in medicine. CO2 laser is considered as one of the earliest lasers used in the medical field (Pick and Powell, 1993).
The CO2 laser has a low power of penetration to tissues that reaches about 0.05 mm. It works only superficially and eliminates the superficial layers of the injured area. In OLP the deeper layer of subepithelial connective tissue and lymphocytic infiltrate cannot be reached (MLA Anderson, 2000).
Diode lasers provide great benefits over many other lasers because of its small size comparable to other types of laser. Application of diode 980 in 8w power in defocused continuous mode will elevate the temperature of affected tissues to above 50 degrees and less than 100 degree; this temperature results in protein denaturation which causes destruction of the diseased epithelium with its surface antigen, in addition to all the immune reaction components present in the range of diode laser treatment, as antigen antibodies, cytotoxic proteins and subepithelial lymphocytic infiltrate due to its deeper penetration which gives long remission duration. Besides, it provides a dressing layer for the treatment site that helps to decrease post-operative pain, and accelerate healing with less risk of secondary infection (Catone and Alling, 1997).
Using diode laser seems to be an easy and effective treatment option for OLP failing to respond to steroids or in cases where the cosmetic sequelae are an issue (Sivolella et al., 2012).
Although multiple studies have evaluated the efficacy of diode laser for the treatment of OLP, there is a lack of class one evidence in this regard. Therefore, we conducted this systematic review to synthesize evidence from published literature. About the safety and efficacy of Diode Laser for the treatment of OLP.

Methods:-
We followed the PRISMA checklist during the preparation of this systematic review and Meta-analysis. All steps were performed in strict accordance to the Cochrane Handbook for systematic Review of interventional studies.
Criteria for considering studies to this review:-1. We included studies that meet the following inclusion criteria: 2. Study design: studies that were prospective observational studies randomized controlled trials, quasi experimental studies, and single arm studies. 3. Population: studies whose population patients were suffering from OLP. 4. Intervention: studies where OLP patients received treatment with lasers 5. Comparison: studies with/without control group We excluded retrospective studies, thesis, and conference abstracts. We also, excluded studies whose data were not reliable for extraction or analysis.

Literature search and screening:-
We searched PubMed through May 2017 using relevant keywords: (OLP, diode laser and LLLT)). Titles and abstracts of retrieved records were screened for eligibility according to the previously mentioned criteria.

Data extraction:-
A uniform online data extraction sheet was constructed. The sheet includes data extracted in four domains: (1) characteristics of study design, (2) characteristics of study population, (3) risk of bias domains, and (4) data of the safety and efficacy of the laser.

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Quality assessment:-The quality of randomized controlled trials was assessed by the Cochrane Risk of bias assessment tool, Cochrane handbook of systematic reviews of interventions 5.1.0 (Higgins and Green, 2011). The non-controlled studies were assessed by quality assessment of before-after (Pre-Post) studies with no control group (NIH and NHLBI, 2014). The quality of the included studies was acceptable.

Data analysis:-
The proportion of patients who achieved clinical improvement in each study was pooled together using the Mantel Hansel method in a random effect model meta-analysis. The mean decrease in visual analogue score and area of lesion were pooled as mean difference with 95% confidence intervals in a random effect model. Heterogeneity was assessed by I-square and Chi-square tests. The analysis was carried out using the Review manager software.
Results:-Results of literature search:-Our search strategy retrieved 1034 records. Following title and abstracts screening, 16 articles were found relevant to our research question. Of them, 14 articles were found relevant to our research question and met our eligibility criteria and were included in this systematic review and meta-analysis. The PRISMA flow diagram for the study selection process is shown in diagram 1.

Characteristics of the included studies:-
Of the 14 included studies, 5 RCT (randomized control trail), 6 cases series studies, 2 were case report studies and 1clinical study. The summary of study design, population characteristics and diode laser information of each study is shown in tables 1& 2.     Corticosteroids) with 95% confidence interval.

Recurrence:-
No cases of recurrence were reported in all the included studies except for the study (Soliman et al., 2005). Where three patients treated with LLLT had a recurrence of the disease after three months in one case and after four months in the other two.

Complications:-
There were no complications mostly resulting from using the treatment. Functional disability was reported in the study (Soliman et al., 2005). The argued that this disability was a result of pain and edema associated with laser therapy.
Therapy side effects:-Edema found in cheeks sites in all patients just after 3 days' post-treatment. This edema had a regressive course over two weeks then was no traces of its study (Soliman et al., 2005).

Decrease in size of lesion:-
Most studies reported positive results supporting rapid healing of the treated lesions that could be up to a mean of 90% ± 10.6% .

Functional disorders (scarring and bleeding):-
There was better symptomatology post-treatment in almost all studies. 79.27% of the patients had been relieved just after four sessions (Cafaro et al., 2014).

Summary of findings:-
In this systematic review, we have reviewed the evidence regarding the potential of treating OLP lesions using LLLT. Diode laser seems to be a safe and well tolerable method for relieving the symptoms and burden OLP. Postoperative pain reported on VAS was significantly lower after the operation and on the long follow-up. Laser therapy had almost no events of therapy side effects, complications, and recurrence rates.
Data available from clinical studies and case series support the use of diode laser in management of these (erosiveatrophic/ unresponsive to local treatment) lesions as it is a potent, well-tolerated, and safe procedure. Cafaro et al., 2014 showed that local steroids provided less improvement in pain scores than that provided by LLLT. In one study, topical steroids achieved more pleasant outcomes than LLLT after treatment (Elshenawy and Eldin,