The Use of Lasers in Disinfection and Cleanliness of Root Canals: a Review

The outcome of root canal treatment is based on efficient disinfection of the root canal system and prevention of reinfection. Current chemomechanical cleaning methods do not always achieve these goals, and insufficient root canal disinfection is the main reason for endodontic failure. Due to high energy content and specific characteristics of laser light, laser treatment has been proposed for cleaning and disinfecting the root canal system. This paper reviews the literature covering the effect of Er:YAG, Er,Cr:YSGG, Nd:YAG and diode laser on the root canal wall in the removal of smear layer and against intracanal bacteria. Recently, the use of laser energy to induce cavitation and acoustic streaming of intracanal irrigants has been investigated. Based on recent literature, it can be concluded that lasers have bactericidal effects. However, they still cannot replace sodium hypochlorite and should be considered as an adjunct to the current chemical root canal disinfection protocols. Certain lasers can help in removing the smear layer and debris and can modify the morphology of the root canal wall. Unfortunately, there have not been enough randomized clinical studies evaluating endodontic treatment outcome following the use of laser.Key words: Disinfection, Root Calan Preparation; Laser Therapy, Low-Level; Smear Layer     

A 10-Year Impact Evaluation of the Universal Salt Iodization (USI) Intervention in Sarawak,Malaysia, 2008–2018

A universal salt iodization (USI) was introduced in Sarawak, Malaysia in 2008 to control the iodine deficiency disorders (IDD) among its population. The purpose of this study is to evaluate the impact of the USI among school children in Sarawak after 10 years of implementation. The data were extracted from 2008 and 2018 Sarawak state-wide IDD surveys. Briefly, both surveys were cross-sectional surveys covering information on the socio-demographic, status of goitre, urinary iodine, and the amount of iodine in the salt samples. A total of 1104 and 988 between the ages of 8 and 10 were involved in the 2008 and 2018 surveys, respectively. The overall prevalence of goitre among the school children in Sarawak was significantly lower in 2018 (0.1%) compared to 2008 (2.9%). The median urinary iodine concentration (UIC) in urine samples had risen significantly from 102.1 µg/L in 2008 to 126.0 µg/L in 2018. In terms of iodine content in salt samples, the median concentration improved significantly in 2018 (35.5 µg/L) compared to 2008 (14.7 µg/L). After 10 years of USI implementation in Sarawak, the results from both surveys confirmed the effectiveness of mandatory USI in increasing the nutritional iodine status of school children in Sarawak.     

Relief of cough and nasal symptoms associated with allergic rhinitis by mometasone furoate nasal spray.

BACKGROUND: Cough commonly occurs as a symptom of seasonal allergic rhinitis (SAR), an inflammatory condition of the nasal mucous membranes that results in rhinorrhea, nasal stuffiness/congestion, nasal itching, and sneezing. Mometasone furoate nasal spray (MFNS, Nasonex, Schering, Kenilworth, NJ), an anti-inflammatory nasal corticosteroid, has been shown to be safe and effective in reducing the nasal inflammation of SAR. OBJECTIVE: To examine the effectiveness of MFNS in relieving SAR-associated cough, in addition to nasal symptoms. METHODS: This was a multicenter, randomized, double-blind study. Patients 12 years of age or older with > or = 1-year history of SAR symptoms, positive skin test to a prevailing seasonal allergen, moderate nasal symptoms, and moderate cough were treated for 14 days with MFNS 200 microg daily (n = 122) or placebo (n = 123). RESULTS: The group treated with MFNS showed significant improvement in the daytime cough severity score at endpoint compared with placebo (P = 0.049). Improvement in the nighttime cough severity score showed a trend in favor of MFNS treatment. Treatment with MFNS significantly improved total nasal symptoms in both the daytime and nighttime compared with placebo at endpoint (P < or = 0.017). Overall daytime symptom scores (cough + total nasal) improved significantly compared with placebo at endpoint (P = 0.005). Overall nighttime symptom scores improved significantly compared with placebo at endpoint (P = 0.028). Treatments were well tolerated, with no significant differences in the incidence of adverse events. CONCLUSIONS: MFNS is effective and well tolerated in the treatment of daytime cough associated with SAR.     

A dose comparison study between XVI and OBI CBCT systems

The purpose of this study is to establish a comprehensive set of dose measurements data obtained from the X-ray Volumetric Imager (XVI, Elekta Oncology Systems) and the On-Board Imager (OBI, Varian Medical Systems) cone-beam CT (CBCT) systems. To this end, two uniform-density cylindrical acrylic phantoms with diameters of 18 cm (head phantom) and 30 cm (body phantom) were used for all measurements. Both phantoms included ion chamber placement holes in the center and at periphery (2 cm below surface). For the XVI unit, the four standard manufacturer-supplied protocols were measured. For the OBI unit, the full bow tie and half bow tie (and no bow tie) filters were used in combination with the two scanning modes; namely, full-fan and half-fan. The total milliampere x seconds (mA s) setting was also varied for each protocol to establish the linear relationship between the dose deposited and the mA s used (with all other factors being held constant). Half-value layers in aluminum (Al) were also measured for beam characteristic determination. For the XVI unit, the average dose ranged from 0.1 to 3.5 cGy with the highest dose measured using the "prostate" protocol with the body phantom. For the OBI unit, the average dose ranged from 1.1 to 8.3 cGy with the highest dose measured using the full-fan protocol with the head phantom. The measured doses were highly linear as a function of mA s, for both units, where the measurement points followed a linear relationship very closely with R2 > 0.99 for all cases. Half-value layers were between 4.6- and 7.0-mm-Al for the two CBCT units where XVI generally had more penetrating beams at the similar kVp settings. In conclusion, a comprehensive series of dose measurements were performed on the XVI and the OBI CBCT units. In the process, many of the important similarities and differences between the two systems were observed and summarized in this work.     

Organ donation and transplant: The Islamic perspective

Islam is the second most practiced religion globally, and the number of Muslims in Western countries has been increasing due to recent trends in migration. Studies have shown that Muslims in the Western world have more negative attitudes toward organ donation and transplantation compared with individuals from other religious backgrounds. Multiple barriers have been postulated that may prevent Muslims from exploring organ donation or transplantation. We conducted a literature review with the goal of summarizing the opinions of major Sunni and Shia scholars and Islamic bodies about organ donation and transplantation, including their opinions and rulings on the neurological determination of death to inform healthcare professionals, community members, and leaders. We also identified factors and attitudes that may prevent members of the Muslim community from achieving equitable access to transplantation or from consenting to donate organs during life or after death. Key factors or concerns identified included: lack of information regarding organ donation, mistrust of the healthcare system, family opinions, sacredness of the body, lack of clear understanding of religious rulings, and opinions of religious leaders. Studies have suggested that partnering with religious leaders to address these concerns may help foster positive attitudes toward organ donation and transplantation.     

Various irrigation protocols for final rinse to improve bond strengths of fiber posts inside the root canal

Irrigation after post space preparation and its effects on the bond strength of different adhesive strategies are still an issue of interest. The aim of the present study was to investigate the effects of various irrigation protocols (IPs) on the push‐out bond strengths of fiber posts. One‐hundred and fifty extracted human anterior teeth were divided into three groups (n = 50 each) and endodontically treated. The post space was irrigated before post placement using the following five IPs in each group: IP1 (control): 5 ml of distilled water; IP2: 5.25% sodium hypochlorite (NaOCl) applied with passive ultrasonic irrigation (PUI); IP3: 1% NaOCl applied with PUI; IP4: 18% ethylenediaminetetracetic acid (EDTA) followed by 5.25% NaOCl; and IP5: 2% chlorhexidine (CHX). Fiber posts placement in each group was performed using three different adhesive strategies. A self‐etch adhesive system revealed higher bond strength (16.2 ± 6.9 MPa) compared with an etch‐and‐rinse adhesive (8.5 ± 4.2 MPa) and a self‐adhesive resin cement (9.2 ± 4.7 MPa). The use of 18% EDTA/5.25% NaOCl increased the bond strength of the self‐adhesive resin cement. Conversely, this IP decreased the bond strength for the etch‐and‐rinse adhesive system, whilst 1% NaOCl enhanced the bond strength for the same system. Consequently, each adhesive strategy may need to be adapted to a specific IP.     

Etiology and pathogenesis of spondyloarthritides

Seronegative spondyloarthritides are inflammatory rheumatic diseases which are classified together because of numerous common and similar clinical, epidemiologic and genetic characteristics. Pathogenesis of seronegative spondyloarthritides is usually described as development of clinical characteristics of the disease in genetically susceptible person in the presence of favorable environmental factors. Development of seronegative spondyloarthritides, notably ankylosing spondylitis, is strongly connected with presence of the HLA-B27 gene. There are clear evidence that HLA-B27 positive individuals have significantly higher risk for disease development. The role of infection in occurence of seronegative spondyloarthritides is not completely understood--its role is better clarified in the case of reactive arthritis than in ankylosing spondylitis. The relation between HLA-B27 gene and infection is not clarified. Molecular mimicry theory is based on similarities between HLA-B27 molecule and microbial particle.