Research in the field of periodontal disease continues to focus on disease-associated microorganisms, as the microbial plaque and the host immune responses are considered to be important causative factors, that are highly responsible for the progression of this disease. The purpose of this article is to compare the reduction in the number of specific periodontopathogens in two test groups according to different therapeutic approaches in periodontal disease and to show possible differences. This article is based on a prospective clinical study involving eighteen subjects with forty-four average periodontal pockets assigned to study groups treated by two different methods, SRP and SRP followed by a single PDT application. Efficiency in removing specific bacterial species was evaluated by PCR testing, at baseline and immediately after treatment. The hypothesis that using SRP + aPDT results in an increased decontamination potential was confirmed statistically, when all five specific bacterial pathogens were investigated together. When the pathogens were considered separately, two of the five microorganisms tested were significantly lower in the SRP + PDT group (p < 0.00), and important germ counts reductions were also observed for the other three. There is also a statistically significant relation between the pain at 48 h postoperatively and the type of treatment the patients received, as resulted from the Questionnaire Form. Our results demonstrate that aPDT, as an adjunctive treatment to conservative mechanical cleaning of root surfaces at sites affected by periodontitis, represents an effective tool in terms of reducing specific periodontopathogen germs.

(1) Background: The prevention of demineralizing lesions at the enamel structure level continues to represent a challenge in daily dental practice. When bacteria influence the pH level, this will decrease below the threshold for remineralization and the dissociation of hydroxyapatite will occur with a high percentage of phosphate and calcium loss. These elements continue to be studied by many authors in order to obtain a working protocol that will lead to their stabilization at the level of the enamel structure, thus preventing the demineralization process. The aim of this study is to evaluate and compare the influence of two types of laser wavelengths on the surface morphology and mineral components of the enamel through an examination with scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDX). (2) Methods: Thirty permanent human incisors extracted for periodontal reasons from patients aged 25–40 years old were selected for this study. Metallic brackets (SS Standard 022 Slot, OC Orthodontics, McMinnville, OR, 97128, USA) were bonded onto each tooth. The buccal surface was randomly assigned three sections: Section A—negative control (no treatment), section B—treated with 980 nm Gallium–Aluminum–Arsenide diode laser (a 300 µm optic fiber was used with 0.8 W output power, energy density of 5.33 J/mm², in continuous mode, for 30 s, oriented perpendicularly to the enamel surface in contact mode) (KaVo GENTLEray 980 Diode Laser, Kaltenbach & Voigt GmbH, Biberach, Germany), and section C—treated with Nd:YAG laser (a 300 µm fiber was carried out at a 1 mm distance from the enamel surface with 0.75 W power, 75 mJ pulse energy, pulse repetition rate of 10 Hz, 5 J/mm² fluency, average exposure time of 30 s, and water cooling assisted) (LIGHTWALKER AT S, M021-5AF/1 S, Fotona d.o.o, Ljubljana, Slovenia). The elements evaluated in this study were calcium (Ca), phosphate (P), oxygen (O), and carbon (C). A one-way analysis of variance, paired t-tests, and independent t-tests were carried out to evaluate the results using the SPSS 19 IBM Statistical package software for Microsoft. (3) Results: The evaluation of the data indicated that both wavelengths produced an increase in Ca wt% (for diode laser the mean of Ca wt% before irradiation was 21.06, while that after treatment reached 28.24; and for Nd:YAG laser, the mean of Ca wt% before irradiation was 21.31, while that after treatment reached 33.88); as well, the 980 nm diode laser decreased P wt% (from 17.20 before irradiation to 16.92 after irradiation) and the Nd:YAG laser increased P wt% (from 17.46 before irradiation to 18.28 after irradiation). These results showed a statistically significant difference at the p < 0.05 level. (4) Conclusions: It can be concluded that the best improvement of enamel chemical composition was obtained with Nd:YAG irradiation.

In orthodontic practice, due to the increased interest among patients in smile aesthetics, different types of brackets are now being used, with those most frequently applied being ones made of polycrystalline and monocrystalline ceramic. The aim of this study was to evaluate the laser Er:YAG-assisted debonding technique compared to conventional methods for removing monocrystalline ceramic brackets from human teeth. The study sample included 60 vital teeth (frontals of the upper jaw) from 10 patients who had monocrystalline ceramic brackets and were in the final phase of orthodontic treatment. The debonding procedure was carried out following a split-mouth study design, using either the conventional technique or laser Er:YAG 2940 nm radiation. For each tooth, three variables were evaluated: the patient’s sujective tooth sensitivity associated with the debonding, the time required for debonding, and pulp blood flow microdynamics after the debonding. Three evaluation instruments were used to assess and quantify the treatment effects: (i) the Wong–Baker FACES Pain Rating Scale for pain assessment; (ii) a digital stopwatch/timer to measure the time required to remove the bracket; and (iii) laser Doppler flowmetry (LDF) for recording the pulp blood flow evolution. The statistical analysis of the recorded data showed a statistically significant difference between the two debonding methods regarding the tooth sensitivity during the debonding and the time required for the procedure. The subjective tooth sensitivity was reduced from a mean ± standard deviation of 3.07 ± 1.46 to 0.47 ± 0.86 on the Wong–Baker FACES scale (Wilcoxon signed rank, p < 0.001). The necessary time for debonding was reduced by 0.697 ± 0.703 s per tooth (paired t-test, p < 0.001). There was no difference in the blood microdynamics between the two debonding techniques. According to the results of this study, the laser Er:YAG-assisted debonding technique may be a viable alternative to the conventional method for monocrystalline ceramic brackets.

Maxillary obturator prostheses are dental devices used to close palatal defects created by surgical resection of different type of tumors, congenital malformation or trauma. The most popular material used for denture fabrication is the polymethyl methacrylate (PMMA). In recent years thermoplastic resins has attracted attention as a denture base material. This paper presents experimental compression and traction tests of VertexTMThermoSense from Vertex-Dental B.V. VertexTMThermoSense is a thermoplastic material based on a compounded mixture of Polyamide and pigments used in the fabrication of removable full and partial dental prostheses. Test results show that the average compressive yield strength of the samples is 60.18 MPa. The result of the tensile test showed an average of 49.4 MPa yield strength. VertexTMThermoSense has a very good average of the yield strain of 10%. The average of Young modulus is 1050 MPa.

A new structure and construction of a rehabilitation system for the lower limb is proposed. In many cases rehabilitation is suboptimal due to subjective and empirical choice of evaluation criteria, and therefore three new criteria are introduced. The test bed allows the measurement of three basic parameters (displacement, velocity and force), which are used to calculate the proposed criteria. The system is described in regard with structure, construction and data acquiring. In order to validate the design, a primary set of measurements are performed on the system driven by a healthy person.