**3. Clinical applications and descriptions**

**Figure 2** shows in detail the transmission of the major important laser wavelengths in particular constituents of the skin tissue, while **Figure 3** illustrates the optical absorption characteristics of water, hemoglobin, and melanin and shows precisely the primary constituents of the

**Figure 4** displays the curves of the absorption by the principal components of teeth tissues and laser wavelengths. The biggest absorption occurs with wavelength of approximately

The time duration of treatment session on a given point is significant since it determined the total number of the photons penetrated in the tissue [25]. Photons emitted by laser source do not penetrate into deeper tissue layers even if a given point is irradiated for a longer time [5, 29]. If we mention the above example with the electric torch, we can see that the laser beam will not reach further and it is not more intensive, no matter whether the laser is on for an

In spite of this explanation, the treatment effect is obtained in a deeper layer after the long period of laser irradiation. This phenomenon occurring is similar to the exponential dependence between the transmitted energy (total number of photons transmitted during a thera-

The relation between the time duration of a treatment session and therapeutic effects can be explained by the penetrating photons that initiate the chain reaction which transfers the biological effects of the therapeutic session to the deeper tissue layers and at sides [30].

**Figure 4.** Characteristics of laser beam absorption as the function of wavelength for the main components of the tooth [26].

ranks second, respectively. The abovementioned dependence for particular tooth tissues.

laser radiation—10,600 nm

2900 nm. This is the radiation generated by Er:YAG laser and CO<sup>2</sup>

peutic session) and the depth of penetration [3, 29].

tissue where absorption covers 100%.

22 Prevention, Detection and Management of Oral Cancer

hour or for a minute.

### **3.1. Laser treatment of hard tooth substance (enamel and dentin)**

The carious material contains a higher content of water compared with other surrounding dental healthy hard tissues. As a result, the ablation efficiency of caries is higher than other healthy tissues. There was a possible selectivity in removing carious material by using Er:YAG laser because of the various energy dose requirements to ablate the carious and also healthy tissue leaving those healthy tissues minimally affected. It was found that the Er:YAG laser can ablate the carious dentin effectively with the minimal thermal damage to the other surrounding intact dentins [19, 31, 32] (**Figures 5**–**8**).

The laser can remove infected and softened carious dentin to the same degree as the bur treatment [33]. However, the lower degree of vibration was remarked with the Er:YAG laser treatment (see **Figures 10**–**14**).

**Figure 5.** Decay present on the facial of the maxillary left lateral incisor.

**Figure 6.** The erbium laser used to remove the decay. No anesthesia was required.

**Figure 7.** After caries removal and preparation is complete.

**Figure 8.** Definitive direct-bonded restoration after preparation with the erbium laser [33].

The YSGG laser was cleared for classes I, II, III, IV, and V cavity preps, as well as caries removal, in 1999, with a similar clearance for children soon thereafter (1999). Since then, published reports have demonstrated the laser's ability to reduce and even eliminate the smear layer associated with traditional rotary instruments which can improve surface adhesion and bond strength for restorations [18, 20].

**3.2. Soft tissue**

applications [35].

*3.2.1. Periodontal disease*

any periodontal program [34]. See **Figures 11**–**13**.

at 1–2 mm (when power and spray are at proper settings).

The YSGG laser was the exclusive laser evacuated for major indications in periodontal therapy, while other lasers such as the diode laser or Nd:YAG are absolved for soft tissue applications related to perio; none have been cleared for cutting oral osseous tissues, a core component of

**Figure 9.** Cutting with YSGG (Waterlase). Optimization of the cutting efficiency: distance to tissue should be maintained

Laser Dental Treatment Techniques http://dx.doi.org/10.5772/intechopen.80029 25

The YSGG laser was approved by the FDA for a wide array of indications related to the periodontal health like laser curettage, sulcular debridement, ostectomy, soft tissue flap elevation, removing of pathological tissues from bony sockets, and other related clinical

Also, because the laser reacts at a cellular level and helps to prohibit the pain response, most hard-tissue procedures can be completed without the aid of injected anesthetic [10].

The YSGG laser provides the precise treatment of pits and fissures on the occlusal surfaces of the molars as shown in **Figures 9** and **10**, which has aided in the growing discipline of "micro" and "minimally invasive" dentistry.

**Figure 9.** Cutting with YSGG (Waterlase). Optimization of the cutting efficiency: distance to tissue should be maintained at 1–2 mm (when power and spray are at proper settings).

#### **3.2. Soft tissue**

**Figure 7.** After caries removal and preparation is complete.

24 Prevention, Detection and Management of Oral Cancer

bond strength for restorations [18, 20].

and "minimally invasive" dentistry.

The YSGG laser was cleared for classes I, II, III, IV, and V cavity preps, as well as caries removal, in 1999, with a similar clearance for children soon thereafter (1999). Since then, published reports have demonstrated the laser's ability to reduce and even eliminate the smear layer associated with traditional rotary instruments which can improve surface adhesion and

Also, because the laser reacts at a cellular level and helps to prohibit the pain response, most

The YSGG laser provides the precise treatment of pits and fissures on the occlusal surfaces of the molars as shown in **Figures 9** and **10**, which has aided in the growing discipline of "micro"

hard-tissue procedures can be completed without the aid of injected anesthetic [10].

**Figure 8.** Definitive direct-bonded restoration after preparation with the erbium laser [33].

#### *3.2.1. Periodontal disease*

The YSGG laser was the exclusive laser evacuated for major indications in periodontal therapy, while other lasers such as the diode laser or Nd:YAG are absolved for soft tissue applications related to perio; none have been cleared for cutting oral osseous tissues, a core component of any periodontal program [34]. See **Figures 11**–**13**.

The YSGG laser was approved by the FDA for a wide array of indications related to the periodontal health like laser curettage, sulcular debridement, ostectomy, soft tissue flap elevation, removing of pathological tissues from bony sockets, and other related clinical applications [35].

**Figure 10.** YSGG (Waterlase) parameters. Radiation wavelength and power (energy) density. To reduce cutting speed with Waterlase—"defocus," back off from tissue; there is optimal distance range to cut tissue.

**Figure 11.** Hand scaling [35].

#### *3.2.2. Removal of oral pyogenic granuloma*

A variety of benign soft tissue swellings can be found arising from oral mucosa, most of which are inflammatory hyperplasia and granuloma. These lesions can be divided into those which arise from the mucosa covering the alveolar processes and those which arise elsewhere in the oral cavity [36]. The soft tissue masses which are excised should be sent for histological

Laser Dental Treatment Techniques http://dx.doi.org/10.5772/intechopen.80029 27

examination.

**Figure 13.** Thoroughly debrided root surface [35].

**Figure 12.** Laser-assisted scaling using the Er,Cr:YSGG laser [35].

**Figure 12.** Laser-assisted scaling using the Er,Cr:YSGG laser [35].

**Figure 13.** Thoroughly debrided root surface [35].

*3.2.2. Removal of oral pyogenic granuloma*

26 Prevention, Detection and Management of Oral Cancer

**Figure 11.** Hand scaling [35].

A variety of benign soft tissue swellings can be found arising from oral mucosa, most of which are inflammatory hyperplasia and granuloma. These lesions can be divided into those which

**Figure 10.** YSGG (Waterlase) parameters. Radiation wavelength and power (energy) density. To reduce cutting speed

with Waterlase—"defocus," back off from tissue; there is optimal distance range to cut tissue.

arise from the mucosa covering the alveolar processes and those which arise elsewhere in the oral cavity [36]. The soft tissue masses which are excised should be sent for histological examination.

**Figure 14.** Pyogenic granuloma of the left side of palatal mucosa [8].

0.1 and 1.0 second and works in continuous, single, and repeated pulsed modes. The laser surgical operations had been done at repetitive pulsed mode for 5–8 W maximum power, 0.2–0.4 seconds pulse duration, and 0.2–0.4 seconds pulse interval. The results were evaluated clinically depending on swelling, infection, disturbance of function, pain, and bleeding. The postoperative swelling was minimal to moderate. No sutures were required. No bleeding was seen neither intraoperative nor postoperative period. Postoperative pain was mild in few patients. No disturbance of function was observed

Laser Dental Treatment Techniques http://dx.doi.org/10.5772/intechopen.80029 29

Using the laser dramatically can reduce the need of applying a high-speed drill to the tooth surface for any reason. Nevertheless, it was not yet to completely replace the drill because a

The fact that a single instrument can remove the bulk amounts of enamel, dentin, and decay and then cut the soft tissue around the area typically requires an anesthetic to take the effect.

The YSGG laser has practical viable applications across a wide clinical spectrum like hard tissue, soft tissue, bone, endo, and perio, and because it has utility in both hard and soft tissue applications, the Er,Cr:YSGG laser outperforms other conventional modalities in

laser cannot effectively cut reflective surfaces such as the metal and the porcelain.

It observes an exciting new era of effective laser dentistry.

**Figure 17.** Complete excision of granuloma by diode laser 5 W pulsed mode [8].

The author declares no conflict of interest, financial or otherwise.

[8] (**Figures 14**–**17**).

**4. Conclusion**

many ways.

**Conflict of interest**

**Figure 15.** Complete excision of granuloma by diode laser 5 W pulsed mode [8].

**Figure 16.** Pyogenic granuloma of the right side of maxillary alveolar mucosa [8].

A study by Mahmood et al. [8] has enrolled 35 patients with oral pyogenic granuloma. The type of laser, which was used in this study, is a diode laser with 810 nm wavelength, gallium aluminum arsenide (GaAlAs), output power of 15 W, and pulse duration between

**Figure 17.** Complete excision of granuloma by diode laser 5 W pulsed mode [8].

0.1 and 1.0 second and works in continuous, single, and repeated pulsed modes. The laser surgical operations had been done at repetitive pulsed mode for 5–8 W maximum power, 0.2–0.4 seconds pulse duration, and 0.2–0.4 seconds pulse interval. The results were evaluated clinically depending on swelling, infection, disturbance of function, pain, and bleeding. The postoperative swelling was minimal to moderate. No sutures were required. No bleeding was seen neither intraoperative nor postoperative period. Postoperative pain was mild in few patients. No disturbance of function was observed [8] (**Figures 14**–**17**).
