Iraqi Journal of Laser

BackgroundFemale infection with HPV (human papilla virus) has been established as an essential cause of CIN(cervical intraepithelial neoplasia).The danger of transformation from CIN to frank malignancy should be considered. Objective: The goal of this study isto evaluate theeffectiveness of CO2 laser vaporization of ectocervical lesion high grade squamous intraepithelial lesion (HGSIL). Patients and Methods:Four Female out of 150 affected with HGSIL lesions were submitted to CO2laser vaporization and followed up in 4 months later, and 10women with HGSIL lesion submitted to electrocautery diathermy for the comparison. Results: Among women treated by CO2laser vaporization, 3 women had negative results (clear cervix), at 4 months follow up; one woman had recurrence at 4 months following up, the recurrence was dueto incomplete destruction of the deepest part of the lesion involving the glandular crypts.Conclusion: The preservation of the anatomical integrity of the cervical tissue offers a better follow-up of those patients.Although other treatment modalities are available, CO2 laser represents an acceptable surgical tool for the management of cervical intraepithelial neoplasia (CIN) with minimal complications

Diabetic retinopathy is one of most important complications of diabetes mellitus that can be treated by Nd:YAG laser. Laser is used in ophthalmic practice for photocoagulation and photo disruption. The purpose of this study is to evaluate changes in immunological ,hematological and biochemical values after treatment of diabetic retinopathy by laser.Blood samples from 10 patients suffering from diabetic retinopathywere taken before and after laser treatment to coagulate retina to prevent leakage and hemorraghe to avoid deterioration of vision.In group one(4patients= 40%),blood tests were done one day after treatment. In group two (6patients=60%) tests were done 7 days after treatmentwith laser.The study showed no clear changes in the valuesof biochemical tests(except glucouseisalready high)and hemtologyical tests(except PT, PTT, clotting time and bleeding time for those patients takingl00mg acetylsalicylic acidor warfarin) after irradiation with laser, probably because that main organs that affecting these tests or the elements that involve in these tests havenotbeen irradiateddirectly. The main changes werein mmunoglobulin valueswhich increasedasnoticedinbothgroups,because all light-induced biological effects depend on the parameters of irradiation,the resultssuggest that the laser irradiation may play two principalrolesin immunological changes. First, is stimulation of cellular proliferation, and stimulation of cellular differentiation that is responsible for different types of immunoglobulin. The other suggestion is that laser is acting as a triggering factor which induces systematic effects through the circulation when laser interacts with living cells soit hassystemic effects through circulating blood.

Dental caries (tooth decay) is one of the most prevalent infectious disease and although of multifactorial origin,Streptococcus mutansis considered the principal pathogen in its development (i.e. bacterial processes damage hard tooth structure (enamel, dentine and cementum), producing dental cavities (holes inthe teeth). The bactericidal properties of the Nd:YAG laser hasbeenresearched analyzing its use in caries prevention and bacterial reduction.One hundred twenty five samples were collected from cariousteeth and isolated bacteria were diagnosed using microscopic examination,culture,biochemicaltests, and Api 20 strep system.The results of this study showed that a noticeable decrease in the viability of Streptococcusmutanswere obtained using Q-switched Nd:YAG laser (1064 nm), (3 Hz) repetition frequency,(0.796 ,0.955) J/ cm2energy density by applying (900,1260) number of pulses. Itwas concluded that the bactericidal effect of laser irradiation being dependent onthetype of bacteria, energy density, number of pulses, and laser dose. Suggesting that the results obtained in this study may be useful in the treatment of dental plaque-related disease. Introduction Since Theodore Maiman operated the first ruby laser in July of 1960, biomedical uses of laser have been under investigation(Niemz,2004; Incei,2004;Berrocal et al,2005).Dental caries is a multi-factorial oral disease developed by the localized dissolution of the tooth hard tissues ,caused by acids produced by bacteria in the biofilms (dental plaque ) which eventually leads to cavities(Sbedil et al.,2008;Jeevarthan et al,2007 andMoatet al.,2002). S.mutansis the principal etiological agent of dental caries (Smith et al.,2005;Napimoga et al.,2005) that possesses a variety of mechanisms for survival in the human oral cavity(Chong et al.,2008).Virulence factors of mutans streptococci promoting their colonization and survival in the biofilm,the dental plaque, are adhesin–like cell surface proteins, acidtolerance, acid production and production of glucosyltransferases, fructosyltransferase,mutacin, intracellular polysaccharides,dextranase, glucan-binding protein, Ag I/II (LisaGrőnroos,2000;Kuramitsu,1993 andTamesadaetal.,2004).In addition, many oral streptococci producesIgA protease which impairs the host defense by cleaving the secretory IgA present,and facilitated the primary colonization of mutans streptococci (L. Grőnroos,2000). Colonization of enamel surfaces by the cariogenic bacterium S. mutansis thought to be initiated by attachment to a saliva-derived conditioning film, the acquired enamel pellicle (Moat et al.,2002;Shimotoyodomaetal.,2002 and Shimotoyodoma et al.,2007) via a sucrose-independent initial adherence to the acquired salivary pellicle(i.e., bacterial surface proteins interact with host or bacterial products adsorbed on the tooth surface),followed by sucrose-