Evaluation of the effect of the photobiomodulation therapy on the pain related to dental injections: A preliminary clinical trial.

BACKGROUND: Pain from dental injections is a common reason why people fear dentistry and avoid dental treatment. Thus, researchers have attempted to find methods to decrease dental injection pain. OBJECTIVES: Considering the analgesic effect of the photobiomodulation therapy (PBMT), the aim of this study was to evaluate the effects of PBMT on the pain caused by dental anesthetic injections. MATERIAL AND METHODS: This randomized, split-mouth, triple-blind clinical trial evaluated 60 bilateral canine teeth in 30 dental students. After the random selection of the test (laser) quadrant, the injection site was irradiated with a 940 nm diode laser. Buccal infiltration anesthesia was then administered by injecting lidocaine plus epinephrine with a short needle. The level of pain experienced during the injection was determined using a 100-millimeter visual analog scale (VAS). The same procedure was performed for the control (no laser) quadrant, with the difference being that the laser handpiece was turned on, but no radiation was administered. The 2 groups were compared using the non-parametric Wilcoxon signed-rank test. RESULTS: The mean VAS pain scores were 21.2 ±15.7 for the laser quadrant and 27.9 ±18.9 for the control quadrant; this difference was statistically significant (p = 0.030), but did not seem to be clinically relevant. CONCLUSIONS: The photobiomodulation therapy prior to dental anesthetic injections has no clinical advantage for reducing injection pain.

In vitro Effect of 810 nm and 940 nm Diode Laser Irradiation on Proliferation of Human Gingival Fibroblasts and Expression of Procollagen Gene.

Factors promoting fibroblast proliferation and collagen synthesis can subsequently enhance wound healing. This study aimed to assess the effect of 810 and 940 nm diode laser on fibroblast proliferation and procollagen gene expression. In this study, human gingival fibroblasts were cultured in Dulbecco's modified Eagle's medium and underwent 810 and 940 nm diode laser irradiation once, twice, thrice and four times at 1, 3, 5 and 7 days after culture. The methyl thiazolyl tetrazolium assay was performed to assess the proliferation while the real-time polymerase chain reaction was performed to assess the expression of procollagen gene at the mRNA level. We applied two-way ANOVA and Tukey's test for analysis. Wavelength had no significant effect on the proliferation of gingival fibroblasts, but increasing the number of irradiation sessions of both wavelengths increased the proliferation of human gingival fibroblasts. Significant differences were noted in the number of human gingival fibroblasts between groups irradiated 1 and 4 and also 2 and 4 times. Procollagen gene was well expressed in all groups but its expression was significantly higher in 940 nm laser group after four irradiation cycles. Four times radiation of 940 nm laser seems to be more effective than all others.

Comparison of clinical efficacy of temporalis myofascial flap and dermal graft as interpositional material in treatment of temporomandibular joint ankylosis.

UNLABELLED: Temporomandibular joint (TMJ) ankylosis is a very distressing structural condition. Interpositional arthroplasty has become the acceptable standard for the primary surgical management of TMJ ankylosis. Up to now, diverse interpositional materials have been proposed in this regard, with especial advantages and limitations. The temporalis muscle and facial flap, as well as the dermal graft, are among the most popular ones. This study aimed to compare the short-term clinical consequences between these 2 interpositional materials in patients with operated TMJ ankylosis. MATERIALS AND METHODS: Twenty patients with TMJ ankylosis were randomized in 2 age- and sex-matched 10-patient groups and received either a temporalis muscle and facial flap or a dermal graft as the interpositional material. The maximal incisal opening (MIO) and the amount of lateral excursion (LE) were measured before and 3 months after surgery, and the mandibular deviation (MD) at the mouth opening 3 months after operation was compared between the 2 groups. RESULTS: Twenty patients were enrolled in the study. The presurgical MIO and LE were not significantly different between the 2 groups. Three months after the operation, evaluation of the patients did not reveal a significant difference considering the amount of the MIO, LE, or MD. The mentioned parameters were significantly improved 3 months after the operation in both groups. CONCLUSIONS: The interpositional arthroplasty in TMJ ankylosis patients using either a temporalis muscle and facial flap or a dermal graft would yield a comparable and almost satisfactory clinical outcome.

Efficacy of Low-Level Laser, Hard Occlusal Appliance and Conventional Pharmacotherapy in the Management of Myofascial Pain Dysfunction Syndrome; A Preliminary Study.

Introduction: Myofascial pain dysfunction syndrome (MPDS) is a common temporomandibular joint disorder. Due to its multifactorial etiology, treatment usually involves more than one modality to obtain complementary results. The purpose of this study was to compare the combined effect of a low-level laser, a hard occlusal appliance, and conventional pharmacotherapy with pharmacotherapy only in the management of patients with MPDS. Methods: In this study, 15 patients with MPDS were diagnosed and randomly assigned to 3 groups (n=5). Subjects in Group 1 were treated with pharmacotherapy (PT); Group 2 received the diode laser (940 nm gallium arsenide) every other day for a total of 10 sessions, plus pharmacotherapy (PTL) and Group 3 were given hard occlusal splint 12 h/day for 4 weeks, plus pharmacotherapy (PTO). The intensity of pain was measured using the visual analog scale (VAS) prior to the treatment, 2 and 4 weeks after the onset of treatment and 2 weeks later. The maximum painless mouth opening and pain intensity at muscle palpation were also recorded. Comparisons were made between the groups via repeated measure analysis of variance (ANOVA) (P<0.05). Results: Pain relief in the subjective VAS was observed in both laser and appliance groups in the third and fourth examination sessions (P<0.05). No statistically significant reduction in pain was noted using pharmacotherapy only. The maximum painless mouth opening and muscle tenderness were not significantly different between the 3 groups (P>0.05). Conclusion: Both the laser and the occlusal appliance combined with pharmacotherapy proved to be effective for pain reduction in patients with MPDS. All groups, however, failed to result in a significant improvement in the maximum mouth opening or tenderness in masticatory muscles.

A Comparative Study of Low-Level Laser Therapy and Transcutaneous Electrical Nerve Stimulation as an Adjunct to Pharmaceutical Therapy for Myofascial Pain Dysfunction Syndrome: A Randomized Clinical Trial.

OBJECTIVES: Myofascial pain dysfunction syndrome (MPDS) is the most common form of temporomandibular disorders. Because of the multifactorial nature of the problem, its management usually involves several treatment modalities to maximize their synergistic effects. This randomized clinical trial aimed to assess the efficacy of low-level laser therapy (LLLT) and transcutaneous electrical nerve stimulation (TENS) as an adjunct to pharmaceutical therapy for treatment of MPDS. MATERIALS AND METHODS: This clinical trial evaluated 108 MPDS patients. First, the initial pain intensity of patients was determined using a visual analogue scale (VAS). The first phase of the study included education, awareness, self-care, behavior and relaxation therapy. After 1 month, the pain score was measured again using VAS. Patients who acquired a pain score >1 were divided into three groups of LLLT with diode (GAAlAr) laser with 0.2 W power, TENS, and control, using block randomization. All groups received 10 mg fluoxetine once daily, 0.25 mg clonazepam once daily and 10 mg baclofen three times a day. ANOVA was used to compare the recovery rate of the three groups. RESULTS: Pain in the trapezius muscle and pain on mouth opening resolved faster in the laser + medication group. The recovery rate was faster in the mean muscle pain, general pain reported by patients, pain in the masseter and pterygoid muscles and pain and limitation in lateral movements in both laser + medication and TENS groups. CONCLUSION: Combination of LLLT and TENS with medication accelerated pain relief and resolved movement restrictions in MPDS patients.(IRCT registration number: IRCT201411113144N4).

Debonding Time and Dental Pulp Temperature With the Er, Cr: YSGG Laser for Debonding Feldespathic and Lithium Disilicate Veneers.

Introduction: The removal of ceramic veneers is a time-consuming procedure in a dental office. Little research has been done in alternative removal techniques for ceramic veneers. The objective of this study was to evaluate the removal of feldspathic and lithium disilicate reinforced glass ceramic veneers by Er, Cr: YSGG and to measure debonding time and pulpal temperature increase during veneer removal. Methods: Fifty-seven bovine incisor teeth were prepared and divided into 3 groups. Ceramic specimens with a thickness of 0.7mm, a width of 4mm and a length of 8 mm were fabricated from feldspathic ceramic, lithium disilicate reinforced glass ceramic HT (high translucency) and lithium disilicate reinforced glass ceramic MO (medium opacity) (19 for each group). Specimens were cemented on the labial surface of incisors using resin cement. The Er, Cr: YSGG laser was applied to each specimen at 2.5 W and 25 Hz. Debonding time was measured for each specimen, and the intrapulpal temperature was detected in 3 specimens for each group. Data were analyzed via one-way analysis of variance (ANOVA) at significance level of 0.05 (α = 0.05). Results: Mean debonding time was 103.68 (26.76), 106.58 (47.22) and 103.84 (32.90) seconds for feldspathic, lithium disilicate MO, and lithium disilicate HT respectively. There was no significant statistical difference among the groups (P value = 0.96). The intrapulpal temperature increase was less than 1°C in all groups. Conclusion: Er, Cr: YSGG can successfully be used to efficiently debond feldspathic and lithium disilicate reinforced glass ceramic veneers. There was no significant difference for debonding time among these ceramic materials. During ceramic laminate veneer removal by laser irradiation, no irritating temperature rise was detected.

Repair bond strength of composite: Effect of surface treatment and type of composite.

BACKGROUND: By an increase in use of composite restorations, some defects are also seen in these restorations, which need to be repaired. Since complete replacement of an old restoration may compromise the tooth structure, repair of defect is a more practical approach if there is no caries recurrence. Risk of pulp injury also decreases as such. One major challenge in restoration repair is to obtain a durable bond between the new and old composite. Laser irradiation has been suggested for surface preparation of old composite. This study aimed to assess the effect of composite surface preparation with Er,Cr:YSGG laser on microtensile bond strength to new composite. MATERIAL AND METHODS: A total of 18 blocks were fabricated in three groups of nanohybrid, microhybrid and Beautiful II giomer measuring 4x7x7 mm and subjected to 10,000 thermal cycles between 5-55°C with 30 seconds of dwell time. The samples were randomly assigned to no surface treatment (etching and bonding) or laser plus etching and bonding groups. Composite cylinders measuring 4x7x7 mm were fabricated of Beautiful, nanohybrid and microhybrid composites on old composite surfaces and subjected to 500 thermal cycles for 50 seconds between 5-55°C with 30 seconds of dwell time. Each block was sectioned into 10 samples and they were subjected to microtensile bond strength test. Data were analyzed using ANOVA and Tukey's test. RESULTS: In all composites, the mean bond strength in laser subgroups was higher than that in control subgroups except for giomer, which showed lower bond strength in laser subgroup. The lowest mean bond strength was noted in repair of Z350XT with Z350XT when the surface of old composite was etched (10.92 MPa). The highest mean bond strength was noted in repair of Z250 with giomer when the old composite surface was irradiated with laser (30.55 MPa). CONCLUSIONS: Er,Cr:YSGG laser plus etching increased the bond strength in all groups except for giomer group, which showed a reduction in bond strength. Key words:Composite resins, surface treatment, tensile bond strength, laser, er,cr:ysgg, giomer.

Evaluation of levels of knowledge about etiology and symptoms of oral cancer in southern Iran.

BACKGROUND: Knowledge regarding risk factors and primary signs of oral cancer in the general population can help them to avoid risky behaviour and seek timely advice from a physician. The aim of this study was to survey adult knowledge about risk factors and signs of oral cancer in Shiraz Dental University. MATERIALS AND METHODS: In this descriptive cross-sectional study using an investigator-made questionnaire, 783 adults who were referred to Shiraz Dental University participated. Questionnaire data were analyzed by ANOVA and T-test. RESULTS: The results showed that 32.3% of participants were aware of oral cancer and gained their knowledge from the media. The risk factors mentioned by these participants was as follows: sunlight 30.8%, hot and peppery food 40.7%, alcoholic drinks 47.4% and smoking 73.6% (there was significant relationship for drinking alcohol and gender, education and times of using dental service, p<0.05). They also mentioned the primary signs of oral cancer as follows: red patch without pain 27.8%, white patch without pain 13.5% and prolong scarring without pain 56.7% (there was significant relationship between these three signs and education and times of using dental service, p<0.05). The mean knowledge about the risk factors and signs of oral cancer were 1.94 from 5 with 1.14 standard deviation and 0.96 from 3 with 0.93 standard deviation. CONCLUSIONS: The observed low level of knowledge of people regarding both risk factors and signs of oral cancer emphasizes the need for more efforts to be made about the above mentioned issues by the media.

HER2/neu expression in head and neck squamous cell carcinoma patients is not significantly elevated.

BACKGROUND: HER2/neu, a member of EGFR family, is over expressed in some tumors .The purpose of this study was to determine the salivary level and tissue expression of HER2/neu in patients with head and neck squamous cell carcinoma (HNSCC) and any correlation with clinicopathologic parameters. METHODS: An enzyme- linked immunosorbent assay (ELISA) was used to evaluate the salivary level and immunohistochemistry (IHC) to assess tissue expression of HER2/neu in 28 patients with HNSCC and 25 healthy controls. RESULTS: The salivary levels of HER2/neu in HNSCC patients was not significantly higher than in the healthy controls (p>0.005). There was no apparent correlation in salivary HER2/neu level with clinicopathological features such as age, sex, grade, tumor size and nodal status. All HNSCC specimens were positive (membranous or/and cytoplasmic) for HER2/ neu, except one sample. Only one HNSCC specimen was stained in cytoplasm purely. All control specimens were membranous and cytoplasmic positive for HER2/neu. There was a significant difference between cytoplasmic staining in case and control groups (p-value<0.05). CONCLUSION: In our cases, no overexpression of HER2/neu was observed. Thus, our findings suggested that the use of Her-2 as a salivary marker of HNSCC cannot be recommended.

The Incidence of Intravascular Needle Entrance during Inferior Alveolar Nerve Block Injection.

BACKGROUND AND AIMS: Dentists administer thousands of local anesthetic injections every day. Injection to a highly vascular area such as pterygomandibular space during an inferior alveolar nerve block has a high risk of intravascular needle entrance. Accidental intravascular injection of local anesthetic agent with vasoconstrictor may result in cardiovascular and central nervous system toxicity, as well as tachycardia and hypertension. There are reports that indicate aspiration is not performed in every injection. The aim of the present study was to assess the incidence of intravascular needle entrance in inferior alveolar nerve block injections. MATERIALS AND METHODS: Three experienced oral and maxillofacial surgeons performed 359 inferior alveolar nerve block injections using direct or indirect techniques, and reported the results of aspiration. Aspirable syringes and 27 gauge long needles were used, and the method of aspiration was similar in all cases. Data were analyzed using t-test. RESULTS: 15.3% of inferior alveolar nerve block injections were aspiration positive. Intravascular needle entrance was seen in 14.2% of cases using direct and 23.3% of cases using indirect block injection techniques. Of all injections, 15.8% were intravascular on the right side and 14.8% were intravascular on the left. There were no statistically significant differences between direct or indirect block injection techniques (P = 0.127) and between right and left injection sites (P = 0.778). CONCLUSION: According to our findings, the incidence of intravascular needle entrance during inferior alveolar nerve block injection was relatively high. It seems that technique and maneuver of injection have no considerable effect in incidence of intravascular needle entrance.

Central giant cell granuloma of the posterior maxilla: a case report.

Central giant cell granuloma (CGCG), formerly called giant cell reparative granuloma, is a non-neoplastic proliferative lesion of unknown etiol-ogy. It occurs most commonly in the mandible. The case reported here resembled a wide variety of conditions that led to a misdiagnosis both on clinical and radiographic examinations but was histopathologically diagnosed as CGCG. We describe a case of CGCG arising from the poste-rior maxilla to highlight the importance of histo-pathology in the diagnosis of this enigmatic le-sion.