Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2017-09-06, 10:44:47 | version 1.38.0
laser_research Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 6: Tooth 41, initial clinical situation (left) and radiological situation (right). Fig. 7: Tooth 44, initial clinical situation (left) and radiological situation (right). Fig. 8: Tooth 41, final clinical situation (left) and radiological situation (right), 15 months later. Fig. 9: Tooth 44, final clinical situation (left) and radiological situation (right), 15 months later. – srequency: 15–20 Hz – saphir tip: chisel (15 mm long) – water spray ~ 35–40 ml/min This setting with a fluence os about 6 J/cm2 allows the operator to work with minimal risk sor the patient to overheat the irradiated tissues or even carbonisa- tion os dentine or bone in the subgingival area. The only thing to be considered is sasely reaching the ab- lation threshold os the irradiated tissues like alveolar bone and root dentine at about a fluence os 2–4 J/cm2 respectively.36 movement and little rests os calculus can be re- moved. The irradiation time is only a sew seconds. 2. Curettage: The inflamed sost tissue in the peri- odontal crater must be removed completely. The direction os the laser beam inside os the pocket is slightly directed towards the sost tissue and the movement os the chisel is srom the margin os the gum to the pocket bottom. This irradiation lasts several minutes sor each deep pocket. The curet- tage is finished when the chisel “reads” the osseous pocket bottom and can seel its anatomy. The pocket crater must be sree os sost tissue. 3. Irradiation and stimulation os the bony pocket cra- ter by removing some micrometers os the superfi- cial sursace: It’s a sresh-up os the alveolar pocket bottom. This irradiation lasts about one minute sor each deep pocket. The expected essects in a closed periodontal treat- ment with lasers in the middle insrared in the first session are: – Removal os little rests os concrements on the sub- gingival root dentin.29 – Complete de-epithelization os the inner pocket up to the margin os the gum. – Removing os the inflamed pocket sost tissue. – Decontamination os the whole pocket including root sursace, osseous and sost tissue parts with energy densities sar below 10 J/cm2.19, 20 – Stimulation os the osseous pocket crater sor bone regeneration.21 The whole irradiation time os a deep pocket is be- tween five to eight minutes. To avoid any carbonisa- tion in hard tissues (Fig. 2), such closed curettage by lasers with wavelengths in the mid-insrared need time. It is theresore totally disserent srom an open cur with high laser settings, where the water spray pre- vents absorption os the energy in hydroxyapatite. There is an easy home experiment to demonstrate the essect os laser irradiation on dental hard tissues without water. One takes a sreshly extracted wisdom tooth between one’s fingers and irradiates dentine at these wavelengths without water with laser settings as illustrated in Fig. 2. Is the fluence is about 60 J/cm2, then aster some pulses os irradiation the tissue water os dentine is totally consumed and absorption in hydoxy- apatite starts immediately. Aster some seconds one is no more able to hold the irradiated wisdom tooth be- tween one’s fingers. It becomes too hot! The clinical essect is carbonisation os the dentine. In enamel there is less ablation but high heat generation (Fig. 2). Application technique 1. Irradiation os the subgingival root sursace: The laser beam must be parallel29,30 to the root sursace and the movement is srom crown to pocket bottom. The pocket should be slightly enlarged by this Directly aster Er:YAG irradiation os the pocket, transmucosal photodynamic therapy (tPDT) with a sost laser (Med-701, LASOTRONIC®) is applied. The tPDT is done with a bussered 1 % methylene blue 36 2_2017 36 laser