The effect of laser therapy for the treatment of dentin hypersensitivity on surface roughness and bacterial adhesion.

The aim of the study was to measure the degree of dentine surface roughness caused by five distinct lasers used to treat dentine hypersensitivity, as well as to evaluate the subsequent bacterial colonization on these irradiated surfaces. Sixty human maxillary premolar teeth without caries or restoration which were extracted for periodontal reasons were used in this study. Five different types of lasers were applied to the root dentin surface. Tested samples were divided into six groups of 10 samples each; control, diode (810 nm), diode (980 nm), Nd: YAG, Er: YAG, and Er, Cr: YSGG laser groups. The arithmetic mean of the surface roughness values (Ra) and the average roughness over a measurement area (Sa) were measured pre- and post-application using any of the laser types. Swab samples were then collected from the dentin surface. Following a 24-hour incubation period at 37 °C, the colony forming units were counted using a stereoscope. The results demonstrated a statistically significant difference in the surface roughness values pre- and post-application (Ra and Sa, respectively) in the Er, Cr: YSGG laser group (p = 0.037,p = 0.007). No significant difference was observed in the other groups (p > 0.05). There was no statistically significant difference in the number of bacterial colonies observed between the test and control groups. Diode and Nd: YAG lasers showed either a decrease or no change in surface roughness; however, the hard tissue lasers (Er: YAG, Er, Cr: YSGG) showed an increase. The Er: YAG and Nd: YAG laser groups exhibited decreased bacterial adhesion compared to the other groups.

Efficiency of HEPA-filtered extra-oral suction unit on aerosols during prosthetic dental preparation: A pilot study.

OBJECTIVES: Aerosols formed during dental treatments have a huge risk for the spread of bacteria and viruses. This study is aimed at determining which part of the working area and at what size aerosol is formed and ensuring more effective use of HEPA-filtered devices. MATERIALS AND METHODS: Anterior tooth preparation was performed by one dentist with one patient. Particle measurements were made using an airborne particle counter and were taken at four different locations: the chest of the patient, the chest of the dentist, the center of the room, and near the window. Three groups were determined for this study: group 1: measurement in a 24-h ventilated room (before the tooth preparation, empty room), group 2: measurement with the use of saliva ejector (SE), and group 3: measurement with the use of saliva ejector and HEPA-filtered extra-oral suction (HEOS) unit. RESULTS: The particles generated during tooth preparation were separated according to their sizes; the concentration in different locations of the room and the efficiency of the HEOS unit were examined. CONCLUSIONS: The present study showed that as the particle size increases, the rate of spread away from the dentist's working area decreases. The HEPA-filtered extra-oral suction unit is more effective on particles smaller than 0.5 microns. Therefore, infection control methods should be arranged according to these results. CLINICAL RELEVANCE: The effective and accurate use of HEPA-filtered devices in clinics significantly reduces the spread of bacterial and viral infections and cross-infection.

Effectiveness of in-office bleaching treatment with different activation techniques on tooth color changes and sensitivity: A randomized clinical trial.

PURPOSE: To investigate the effectiveness of different light activation methods for in-office bleaching agents in terms of color change durability and tooth sensitivity (TS). METHODS: 80 subjects were randomly divided into four groups (n= 20). A bleaching agent (40% H2O2) was activated using a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, an 810-nm diode laser, a light-emitting diode (LED), and conventional (chemical) treatment. The CIE L*a*b* system and ΔE* values were used to measure color changes in the teeth using a spectrophotometer. TS was measured using the visual analogue scale (VAS). The measurements were performed before the treatment, immediately afterwards, and 2 weeks, 1 month, and 6 months later. A P< 0.05 was accepted as statistically significant. RESULTS: The most statistically significant color change occurred in the 2nd week (⏊E2) in all groups (P< 0.05). However, the most color change in the 2nd week (ΔE2) occurred in the Nd:YAG group, yet there was no statistically significant result between Nd:YAG and LED (P< 0.05). After the procedure (VAS2), a statistically significant increase in TS was observed in all groups (P< 0.05), with the highest sensitivity observed in the LED group; significant differences were observed between the LED and the other groups (P< 0.05). CLINICAL SIGNIFICANCE: Although all light activation techniques showed noticeable color changes, the conventional technique showed appreciable color change at the 6-month follow-up. Nd:YAG and diode laser activation can be preferable alternatives to LED and conventional activation in clinical practice as they bleach more and faster, decrease the number of sessions and chair time, and cause minimum sensitivity.

The effects of posterior alveolar bone height on the height of maxillary sinus septa.

PURPOSE: The purpose of this study was to evaluate whether posterior alveolar bone height affects maxillary sinus septa (MSS) height in dentate and edentulous patients, as determined by cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This retrospective analysis enrolled 166 patients (91 men and 75 women) with a mean age of 43.12 ± 15.26 years (range 18-74 years), who had at least one MSS on CBCT images. MSS were categorized into three regions: anterior, middle, and posterior. Patients were categorized as complete or partial posterior edentulous or fully posterior dentate. The maximum vertical diameter of the sinus septa and alveolar bone height was analyzed in sagittal CBCT sections; P < 0.05 was regarded as statistically significant. RESULTS: We found 210 MSS among the patients in this study. Of the 166 patients, 36 had bilateral septa and 4 had three septa. The septa were mainly located in the middle region in the dentate (n = 70; 33.3%) and edentulous (n = 59; 28.1%) patients. The mean septal height was significantly higher in men than in women (P = 0.024). In dentate patients, the mean MSS height was similar among the three regions. In edentulous patients, the anterior mean MSS height (4.96 ± 2.77 mm) was lower than that of the other two regions. There was no statistically significant association between septa and alveolar bone height in any anatomic region, in either group (r = 0.022; P = 0.748). CONCLUSIONS: These results suggest that MSS height is not influenced by alveolar bone height.

A Simplified Way for the Stabilization of Pediatric Mandibular Fracture With an Occlusal Splint.

The management of pediatric mandibular fractures is challenging for maxillofacial surgeons due to ongoing mandibular growth involving tooth buds. The treatment of such fractures has been a topic of much research. Generally accepted methods for the treatment of mandibular parasymphyseal or symphyseal fractures in children are conservative approaches involving the use of acrylic splints, lateral compression with an open-cap splint stabilized by circummandibular wiring, and maxillomandibular fixation with an arch bar and eyelet wiring. The aim of this technical note was to describe a straightforward approach to the treatment of pediatric mandibular fractures, in which an occlusal splint is secured to prevent trauma to the soft tissue, without the need for general anesthesia.

Effectiveness of occlusal splints and low-level laser therapy on myofascial pain.

The present study was designed to evaluate the effects of low-level laser (Nd:YAG) therapy and occlusal splints in patients with signs and symptoms of temporomandibular disorders (TMD) characterized with myofascial pain (MP). A total of 30 patients were selected after being diagnosed with MP according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TDM). The patients were divided into three groups. The first group was occlusal splint (OS) group A (n = 10), the second was low-level laser therapy (LLLT) group B (n = 10), and the last group C was placebo (n = 10). LLLT (1,064 nm, 8 j/cm(2), 250 mW, Fotona) was applied to the patients in the study group once a day for 10 days, for a total of ten sessions. The same parameters and application times were used for placebo group, but the patients were not irradiated. The application was on the trigger points. The patients in the OS group were instructed to wear occlusal splints 12 h/day for 3 weeks. Functional examination was based on RDC/TDM, and pressure pain values were obtained with the Visual Analog Scale. Comparisons were made between the groups before and after the treatment according to Wilcoxon, Mann-Whitney U, and Kruskal-Wallis tests. The pain score values decreased significantly after both LLLT (p < 0.05) and occlusal splint therapy (p < 0.05) compared to placebo group (p < 0.05). There was no significant difference between LLLT and OS groups after treatment (p > 0.05). OS and LLLT are effective for decreasing MP. In addition, this particular type of LLLT is as effective as occlusal splint for pain relief.

Evaluation of graphene oxide-doped poly-lactic-co-glycolic acid (GO-PLGA) nanofiber absorbable plates and titanium plates for bone stability and healing in mandibular corpus fractures: An experimental study.

BACKGROUND: Open reduction with internal fixation is the preferred treatment option for displaced facial bone fractures. The superior mechanical properties of metallic plates have made them the most widely used material in existing bone fixation systems. However, after the healing period, these permanent plates can cause various problems. Alternative bioresorbable materials are being investigated to reduce these potential problems. This study compares bone stability and viability by using graphene oxide (GO)-doped poly-lactic-co-glycolic acid (PLGA) nanofiber plates and titanium plates for rats with fractured mandibles. MATERIALS AND METHODS: The study included 20 male Sprague-Dawley rats, divided into four groups: a control group (Group I), a mandibular fracture group with no additional application (Group II), a mandibular fracture group repaired with titanium plates (Group III), and a mandibular fracture group repaired with GO-PLGA plates (Group IV). After 2 months, all of the rats were euthanized. A bone compression test was performed to assess bone stability, and a histological examination was performed to evaluate bone healing. RESULTS: The osteocyte lacunae, Haversian ducts, canaliculi, and vascular structures of Group IV were found to be higher. In the compression test, vertical compression was applied to the bone axis, and Group IV had a higher maximum load and maximum stretch. GO-PLGA plates were found to be statistically superior to titanium plates in terms of both bone stability and bone healing (p < 0.05). CONCLUSIONS: The present study found that GO-PLGA plates are more effective than titanium plates for the treatment of mandibular corpus fractures.

Effect of surface finishing treatments on the color stability of CAD/CAM materials.

PURPOSE: The aim of this study was to evaluate the effect of different surface finishing processes on the color stabilities of lithium disilicate glass-ceramics, zirconia-reinforced lithium silicate ceramics, and resin nanoceramics after artificial ageing. MATERIALS AND METHODS: 216 samples were prepared from 3 different CAD/CAM materials (LAVA Ultimate, IPS e.max CAD, VITA Suprinity) with A1 HT color at a size of 14 × 12 mm and a thickness of 0.5 ± 0.05 mm. Color measurements of the samples were performed with a spectrophotometer using color parameters and CIE Lab color system on a gray backing between baseline color and after 5000 cycles of artificial ageing in 4 stages (i.e. the first measurement before the treatment, the second measurement after polishing, the third measurement after cement application, and the fourth measurement after artificial ageing). The results were evaluated using the Variance analysis and Fisher's LSD test. RESULTS: Resin nanoceramics (LU) exhibited higher color change values than zirconia-reinforced lithium silicate (VS) and lithium disilicate (EC) ceramics after artificial ageing. Manual polishing and glazing resulted in similar color change for LU and VS (P>.05). In the EC group, glazing provided statistically different results as compared to the manual polishing and control groups (P<.05). Among the ceramic groups, color change values of the subgroup, which was treated by glazing, of the zirconia-reinforced lithium silicate (VS) and lithium disilicate (EC) samples were below the clinically acceptable level (ΔE < 3.5). CONCLUSION: The lowest color change for all stages was observed in Vita Suprinity.

The potential etiologic factors influencing tinnitus intensity in patients with temporomandibular disorders.

OBJECTIVES: To investigate the potential relationships between the intensity of tinnitus associated with temporomandibular disorders (TMD) and potential etiologic factors, including age, gender, freeway space, sleep bruxism (SB), joint clicking, and headache. METHODS: The sample was comprised of 90 patients without any hearing loss, as confirmed by otorhinolaryngology, who self-reported subjective tinnitus and simultaneous TMD, based on the Research Diagnostic Criteria for TMD (RDC/TMD). RESULTS: The results showed a positive, weak correlation between the intensity of tinnitus and age (r = 0.225, p = 0.033). The presence of SB and headache were seen in higher proportions in the present sample, at 75.5% (n = 68) and 66.6% (n = 60), respectively. CONCLUSIONS: In a population of patients with subjective tinnitus and TMD, no significant associations were found between tinnitus intensity and age, freeway space, SB, clicking presence, and headache, though gender did show a weak correlation with tinnitus intensity.

Efficacy of Low-Level Laser Therapy in Subjective Tinnitus Patients with Temporomandibular Disorders.

OBJECTIVE AND BACKGROUND: Tinnitus is an apparent sound, perceived in the ear with no stimulus. It has been described as a sound originating from the brain. It affects 17% of the general population. Etiological factors for tinnitus include temporomandibular joint disorders (TMJ, TMD) and Costen's syndrome. The aim of treatment is to eliminate the tinnitus or at least decrease its apparent volume. MATERIALS AND METHODS: In total, 46 patients referred to our department with bilateral subjective tinnitus with TMDs were selected for this study. Low-level laser therapy (LLLT) with an neodymium-doped yttrium aluminum garnet (Nd:YAG) (1064 nm) laser, LLLT with a diode laser (810 nm), and placebo treatment were applied to the patients. There were 15 patients each in the Nd:YAG and placebo groups and 16 patients in the 810 nm diode laser group. LLLT was applied for 10 days, once per day. A visual analog scale (VAS) was used, with values between 0 and 10. VAS scores were recorded before treatment, on the last day of treatment, and 1 month after treatment. The VAS scores were the same on the last day of treatment and 1 month after treatment. The VAS scores before treatment and at 1 month after treatment were compared in a statistical analysis. RESULTS: There were statistically significant differences in the Nd:YAG laser (p = 0.001) and 810 nm diode laser groups (p = 0.005), but no difference in the placebo group (p = 0.065). CONCLUSIONS: Both the Nd:YAG and 810 nm diode lasers were effective for the treatment of subjective tinnitus related to TMDs.

Mechanical properties of bovine hydroxyapatite (BHA) composites doped with SiO2, MgO, Al2O3, and ZrO2.

Biologically derived hydroxyapatite from calcinated (at 850 degrees C) bovine bones (BHA) was doped with 5 wt% and 10 wt% of SiO(2), MgO, Al(2)O(3) and ZrO(2) (stabilized with 8% Y(2)O(3)). The aim was to improve the sintering ability and the mechanical properties (compression strength and hardness) of the resultant BHA-composites. Cylindrical samples were sintered at several temperatures between 1,000 and 1,300 degrees C for 4 h in air. The experimental results showed that sintering generally occurs at 1,200 degrees C. The BHA-MgO composites showed the best sintering performance. In the BHA-SiO(2) composites, extended formation of glassy phase occurred at 1,300 degrees C, resulting in structural degradation of the resultant samples. No sound reinforcement was achieved in the case of doping with Al(2)O(3) and zirconia probably due to the big gap between the optimum sintering temperatures of BHA and these two oxides.