Thereza C.C.G.P. Ladalardo

Laser therapy in the treatment of dentine hypersensitivity

Cervical dentine hypersensitivity is the most frequent complaint among reported odontalgias. Thus, this study evaluated the effectiveness of two types of lasers (660 nm wavelength red, and 830 nm wavelength infrared) as dentine desensitizers, as well as both the immediate and late therapeutic effects in individuals 25 to 45 years of age. A total of 40 teeth with cervical exposure were treated in 4 sessions. They were divided into 2 groups according to treatment. A 660 nm wavelength red diode laser and an 830 nm wavelength infrared diode laser were used. Dentine sensitivity to cold nociceptive stimulus was evaluated by means of a pain numeric scale from zero to 10 before each treatment session, at 15 and 30 min after irradiation, and in a follow-up period of 15, 30 and 60 days after the end of treatment. Significant levels of dentinal desensitization were only found in patients ranging in age from 25 to 35 years. The 660 nm red diode laser was more effective than the 830 nm infrared laser and a higher level of desensitization was observed at the 15 and 30 minute post-irradiation examinations. The immediate and late therapeutic effects of the 660 nm red diode laser were more evident in 25-35-year-old patients compared with those of the 830 nm infrared diode laser, in terms of the different age groups.

LLLT in treating dentinary hypersensibility: a histologic study and clinical application

Dental hypersensitivity has been studied for several years and it is reported as a striking painful condition that originates from the exposition of dentinal tubuli as a result of the reduction of the thickness of the enamel or cement. Usually the exposed area is subjected to several kinds of stimuli, resulting in a rapid sharp acute pain. The aim of this study was evaluated the efficiency of LLLT in the treatment of patients with dental hypersensitivity. 1102 teeth of 388 patients from the Laser Center of the Camilo Castelo Branco University were treated with LLLT between 1995-2000. 98 males and 290 females aged 30 to 45 years old were treated. For LLLT, a diode laser was used at 780nm, CW, 40mW, elliptical area of the beam 2mm2, exposure time per point 25s. This corresponds to an equivalent dose of 50 J/cm2 at each point (considering the area of the spot). If a 1cm2 area is considered, the total dose per tooth is 4J/cm2. With the diode laser 830nm, CW, 50mW, elliptical area of the beam 2mm2, exposure time per po int of 20s. This corresponds to an equivalent dose of 50J/cm2 at each point (considering the area of the spot). If a 1cm2 area is considered, the total dose per tooth is 4J/cm2. The results showed 403 (36.57%) out of 1102 teeth required a single session for complete remission of the symptoms. 255 (23.14%) needed two sessions; 182 (16.51%) three sessions; 107 (9.7%) four sessions; and 59 (5.35%) five sessions. 96 (8.71%) did not respond to LLLT and the patients were re-assessed and treatment changed. The more affected tooth was the lower premolar (301 - 27.4%), followed by lower molars (163 - 14.8%), upper premolar (149 - 13.5%), and upper molars (52 - 4.7%), upper canine (119 - 10.7%), upper incisive (108 - 9.9%), lower canine (62 - 5.6%), and upper molars (52 - 4.7%). The result of the present investigation demonstrates indeed that LLLT, when based on the use of correct irradiation parameters, is effective in treating dentinal hypersensitivity as it quickly reduces pain and maintains a prolonged painless status. The authors concluded that the use of LLLT was effective on 91.27% of the cases. Previous studies were carried out by the authors to evaluate histologically the reaction of the dentinal pulp in rats after application of LLLT. The LLLT was shown to be efficient in the stimulation of odontoblast cells, producing reparative dentin and closing dentin tubuli.

Desmineralização dentária de pacientes respiradores orais submetidos à expansão maxilar

UNLABELLED Mouth breathing may cause deformities on the dental arch and be a risk factor for caries and periodontal disease; fixed orthodontic appliances compound the problem. AIM to evaluate mineralization of tooth enamel and the oral cariogenic microbiota of mouth breathers that are using maxillary expanders. MATERIAL AND METHOD a prospective study of 20 mouth-breathing patients with maxillary atresia, aged from 09 to 13 years. Enamel mineralization was measured using a fluorescence technique, before installing the expander and after its removal. The cariogenic microbiota was evaluated by the No Caries®. The t test (p<0.05) was applied for the statistical analysis, and the oral microbiota was analyzed by incidence. RESULTS there was a statistically significant difference in the enamel mineralization level after maxillary expansion; the mean value was 3.08. The colorimetric test showed that the caries development potential was reduced in 45%, increased in 15%, and unaltered in 40% after maxillary expander use. CONCLUSION there was a statistically significant difference in enamel mineralization after maxillary expansion; this difference was within the clinically normal range; the cariogenic potential increased in a small number of patients during orthodontic treatment.

Functional and electrophysiological evaluation of the effect of laser therapy in the treatment of peripheral facial paralysis

This clinical case report relates to a total of 4 patients, carriers of idiopathic facial paralysis, treated with Low Level Laser Therapy using a Gallium-Aluminum-Arsenide diode laser of 780 nm, 50 mW, continuous wave emission, spot size 3 mm2 and total dosage of 20 joules per session distributed to the peripheral trajectory of the injured nerve in a point by point contact mode. Altogether 24 treatment sessions were performed in a period of 12 consecutive weeks twice a week All treated patients presented recovery signs from the initial degree of paralysis.

Comparative clinical study of the effect of LLLT in the immediate and late treatments of hypoesthesia due to surgical procedures

We evaluated the effect of LLLT in 68 patients who presented hypoesthesia due to odontological surgery procedures: dental implant surgeries (N=51); extraction of impacted lower third molars (N=10); endodontics in lower first molars (N=7). Lesions treated within 30 days after the nerve injury had occurred were part of the immediate group, and lesions with more than 30 days from the occurrence of the injury were part of the late group. Treatments were carried out with an infrared diode laser of 40 mW-830nm, continuous wave emission, spot size 3 mm2, and a total dosage of 18 joules per session in a contact mode of application, 20 sessions altogether. The efficacy of laser therapy in peripheral nerve regeneration is also related to the degree of the peripheral nerve lesion, and not only to the lesion duration. LLLT resulted in neurosensory functional improvement in both immediate and late treatments of hypoesthesia.

Evaluation of the mineralization degree of the vestibular surface of the upper central incisors with a 655-nm diode laser in mouth breathers: preliminary results

Mouth breathing unbalances the physiological mechanisms of the dental surface hydration by compromising lip closure, and, very often, causing the vestibular positioning of upper incisors. That variance leads to the interruption of the dental demineralization and remineralization feedback, prevailing a demineralized condition of the dental surface which increases caries risk. The laser fluorescence examination allows an early demineralization diagnosis, thus it makes possible through preventive measures to minimize the risk factor - dental mineral structure loss - in the bacterial infection of the demineralized area, and hence, preventing invasive therapeutical procedures. A DIAGNOdent apparatus was used to evaluate the mineralization degree of the upper central incisors in 40 patients - twenty of them with a mouth breathing diagnosis; the remaining twenty were nasal breathers (control group). Age ranging from 6 to 12 years, both male and female. To measure the vestibular surface of the incisors, it was divided into 3 segments: cervical, medial and incisal. The average of the results pertaining to the mouth breathing patients was as follows: tooth 11 cervical third - 5.45, medial third - 7.15, incisal third - 7.95, and tooth 21 - cervical third - 5.95, medial third - 7.25, incisal third - 8.15. The control patients, nasal breathers, presented the following results: tooth 11 cervical third - 1.75, medial third - 2.30, incisal third - 1.85, and tooth 21 - cervical third - 1.80, medial third - 2.20, incisal third - 2.15. The mouth breathing patients showed demineralization in the teeth examined at the initial stage, subclinical, comparing with the control patients, nasal breathers, who did not present any mineral deficit in these teeth.

LLLT in treating dentinary hypersensitivity: new concepts

Dental hypersensitivity has been studied for several years and it is reported as a strikingly painful condition originating from the exposition of dentinal tubuli . The exposed area is subjected to several kinds of stimuli, resulting in a rapid sharp acute pain. LLLT has been shown to have antiinflammatory, analgesic and cellular effects in both hyperemia and inflammation of the dental pulp. Our previous histological study showed that irradiated animals presented an increased production of dentine and shutting of dentinal tubuli. On the other hand, non-irradiated subjects still showed signals of intense inflammatory reaction and even necrosis at the same experimental times. Irradiated teeth did not show cell degeneration. The LLLT was shown to be efficient in the stimulation of odontoblast cells, producing reparative dentin and closing dentin tubuli. Our clinical studies with 660nm, 790nm and 830nm diode laser, and the total dose per tooth of 4J/cm was shown effective in treating dentinal hypersensitivity as it quickly reduces pain and maintains a prolonged painless status in 91.27 % to 97% of the cases. In a recent study our team observed that significant levels of dentinal desensitization were only found in patients belonging to the 25-35 age group. In conclusion, the results demonstrated indeed that LLLT, when based on the use of correct irradiations parameters is effective in treating hypersensitivity, but the age of patients is one of the factors that may alter the success of treatment due to dentinal sclerosis, which makes the penetration of light more difficult.

Comparative clinical evaluation of the immediate and late analgesic effect of GaAlAs diode lasers of 830 and 660 nm in the treatment of dentine pain: preliminary results

In this comparative clinical study, we aimed at evaluating the immediate and late analgesic effect of GaAlAs diode lasers of 660 nm and 830 nm in treatment of dentine pain. We used GaAlAs diode lasers of 660 nm and 830 nm with 35 mW, continuous wave emission, spot size 1 mm2 and a dosage of 4 joules/cm2 applied to the cervical dentine surface. In total 4 treatment sessions were performed at intervals of 7 days in a period of 4 consecutive weeks. A total of 40 teeth treated were divided into two groups comprising 20 teeth each: one group irradiated with a 660 nm wavelength laser, and the other one with a 830 nm wavelength laser. By means of a quantitative visual analogue scale (V.A.S.), we measured the sensitive responses to cold stimulus pre- treatment, and at a follow-up period of 15 and 30 minutes post-treatment in both groups in order to evaluate the immediate analgesic effect. The late effect was evaluated at a follow-up period of 15 and 30 days. Using the GaAlAs diode laser of 660 nm wavelength resulted in better levels of dentine desensitization, at both immediate and late analgesic effect analysis compared with the use of the GaAlAs diode laser of 830 nm wavelength.

Low-reactive-level laser treatment in facial paralysis

This study was carried out with a 41-year-old female patient with facial paralysis as a consequence of facial nerve injury during neurosurgery. Low-reactive level laser treatment (LLLT) with a diode laser of 830 nm, 40 mw, continuous wave, spot area 3 mm2, was applied twice a week for 2 weeks, then 1 weekly session following up to 30 sessions, resulting in about 80% improvement of the motor activity.