The effect of the combined use of silver diamine fluoride and potassium iodide in disrupting the plaque biofilm microbiome and alleviating tooth discoloration: A systematic review.

Silver diamine fluoride (SDF) is used in minimally invasive dentistry for arresting dental caries. However, discoloration of teeth is a significant side effect that has limited the use of SDF. Hence, the application of potassium iodide (KI) following SDF has been proposed to ameliorate the staining. Although antimicrobial activity is one of the major mechanisms of the caries-arresting effect of SDF, the antimicrobial potency of SDF/KI combination is unclear. Thus, the primary objective of this systematic review was to appraise the studies on the antimicrobial efficacy of SDF/KI combination on cariogenic microbes. The secondary objective was to summarize the evidence on the potential of KI in reducing the discoloration associated with the application of SDF. Electronic databases of Medline via PubMed, Cochrane Library, Web of Science, and EBSCO host were searched for English language manuscripts from January 2005 to 15th November 2020. The reference lists of these manuscripts were manually searched for additional studies. Twelve studies were included in the final analysis, seven of which have investigated the antimicrobial efficacy of SDF/KI, and the rest have examined the anti-staining potential of KI. The exploratory findings from the reviewed articles revealed the promising antimicrobial potential of SDF/KI on cariogenic microbes associated with dentine caries. There is, however, contradictory evidence on the effect of SDF/KI on tooth color. The reviewed in-vitro studies indicated significant effectiveness of KI in preventing staining. A clinical trial on primary dentition showed 25% reduction in the incidence of staining by SDF after applying KI, while a clinical study on root caries in adults showed no significant effect. Within the methodological limitations of this review, we conclude that for arresting dental caries, SDF could be combined with KI, as there may be a lower likelihood of staining. Further, well-designed clinical trials on the antimicrobial and anti-staining effect of SDF/KI are needed to obtain more robust evidence.

Effect of potassium iodide supplementation and teat-dipping on iodine status in dairy cows and milk iodine levels.

Two experiments were designed to determine the effects of dietary iodine and teat-dipping on the iodine status of dairy cows and their milk. Eight mid-lactation Holstein dairy cows with an initial body weight of 642 ± 62 kg and 145 ± 21 d in milk were studied for 2 periods over 44 d. In period 1, all cows were fed a basal diet supplemented with potassium iodide (KI) (10 mg I/Kg DM) for 8 d with no teat-dipping. In period 2, a pre-milking teat-dipping was applied for 10 d followed by no teat-dipping before milking (udder wash without iodine) and then post-dipping treatment was applied for 5 d. Feeding KI increased concentrations of iodine in serum, urine, and milk (P < 0.05). Switching from the KI supplementation to no iodine addition resulted in an immediate decrease of iodine in serum, urine, and milk (P < 0.05). Post teat-dipping resulted in increased iodine levels in serum, urine, and milk (P < 0.05). However, pre-milking teat-dipping did not affect iodine concentration compared to post-dipping. A 250 mL cup of milk from the control and KI-supplemented diets would provide 29.4% and 68.4%, respectively, of the adult-recommended dietary allowance for iodine. In conclusion, milk iodine concentration could be effectively enhanced by KI supplementation and teat-dipping practices.

Influence of Short-Term Dietary and Therapeutic Iodine Restriction on the Therapeutic Effects of Radioactive Iodine Therapy in Patients with Graves' Disease.

Background: Several studies have investigated the factors affecting the effects of radioactive iodine (131I) treatment (RAIT) in patients with Graves' disease. However, the influence of dietary or therapeutic iodine on the effect of RAIT has not been fully elucidated yet. The aim of this study was to investigate whether dietary or therapeutic iodine before RAIT influences the therapeutic effects of RAIT with a fixed-dose regimen and a short-term restriction of iodine intake in an iodine-sufficient area. Materials and Methods: We retrospectively analyzed 81 Japanese patients with Graves' disease treated with the following RAIT regimen: dietary iodine restriction for 7 days as well as discontinuation of antithyroid drugs (ATDs), potassium iodine (KI), or both for 5 days before RAIT. On the day of RAIT, we measured urinary iodine content to estimate daily iodine intake. After RAIT, we adjusted the dose of ATDs, KI, or both according to serum thyroid hormone levels every 1-2 months. Using the data from these patients, we investigated the effect of dietary and therapeutic iodine on the therapeutic effects of RAIT. The therapeutic effects at 1 year after RAIT were evaluated based on the necessity of ATDs, KI, or both. Results: Dietary iodine intake was weakly correlated with 131I uptake (RAIU), but the dose of therapeutic iodine was not correlated with RAIU. The therapeutic effects of RAIT were strongly negatively associated with estimated thyroid volume before RAIT. Neither dietary iodine intake nor therapeutic iodine before RAIT affected this association. Conclusion: This study did not find an association between short-term dietary or therapeutic iodine restriction before RAIT and the therapeutic effects of RAIT in an iodine-sufficient area.

Impact of Dietary Habit, Iodine Supplementation and Smoking Habit on Urinary Iodine Concentration During Pregnancy in a Catalonia Population.

(1) Background: The nutritional status of women during pregnancy can have a considerable effect on maternal and fetal health, and on the perinatal outcome. Aim: to assess the changes occurring in dietary iodine intake, potassium iodide supplementation, and smoking habit, and the impact of these changes on the urinary iodine concentration (UIC) during pregnancy in a population of women in Catalonia (Spain). (2) Methods: Between 2009-2011, an observational study included a cohort of women whose pregnancies were monitored in the public health system in the Central and North Metropolitan areas of Catalonia. Women received individual educational counseling, a dietary questionnaire was completed, and a urine sample was collected for iodine determination at each trimester visit. (3) Results: 633 (67.9%) women answered the questionnaire at all 3 visits. The percentage of women with a desirable UIC (≥150 µg/L) increased from the first to the second trimester and remained stable in the third (57.3%, 68.9%, 68%; p < 0.001). Analysis of the relationship between UIC≥150 µg/L and the women's dietary habits showed that the percentage with UIC ≥150 µg/L increased with greater consumption of milk in the first trimester, and the same was true for iodized salt use in all three trimesters and iodine supplementation in all three. (4) Conclusion: During pregnancy, increased intake of milk, iodized salt, and iodine supplements were associated with an increase in the UIC.

New-onset graves' disease after the initiation of nivolumab therapy for gastric cancer: a case report.

BACKGROUND: Immune checkpoint inhibitors (ICIs) can induce immune-related adverse events (irAEs) including thyroid dysfunction. There are only a few reports on Graves' disease induced by ICIs. We report a case of new-onset Graves' disease after the initiation of nivolumab therapy in a patient receiving gastric cancer treatment. CASE PRESENTATION: The patient was a 66-year-old Japanese man, who was administered nivolumab (240 mg every 3 weeks) as a third-line therapy for stage IVb gastric cancer. His thyroid function was normal before the initiation of nivolumab therapy. However, he developed thyrotoxicosis before the third administration of nivolumab. Elevated, bilateral, and diffuse uptake of radioactive tracer was observed in the 99mTc-pertechnetate scintigraphy. Furthermore, the thyroid-stimulating hormone receptor antibody (TRAb) and thyroid-stimulating antibody (TSAb) test results, which were negative before the first administration of nivolumab, were positive after starting the therapy. The patient was diagnosed with Graves' disease, and the treatment with methimazole and potassium iodide restored thyroid function. CONCLUSIONS: This is the first complete report of a case of new-onset Graves' disease after starting nivolumab therapy, confirmed by diffusely increased thyroid uptake in scintigraphy and the positive conversion of antibodies against thyroid-stimulating hormone receptor. It is important to perform thyroid scintigraphy and ultrasonography to accurately diagnose and treat ICI-induced thyrotoxicosis, because there are various cases in which Graves' disease is developed with negative and positive TRAb titres.

Dietary iodine intake, therapy with radioiodine, and anaplastic thyroid carcinoma.

Background Anaplastic thyroid cancer (ATC) is one of the most aggressive tumors. The aim of the study was to determine the correlation between a higher dietary intake of iodine, frequency of ATC and the characteristics of ATC, and to find out how often patients with ATC had a history of radioiodine (RAI) therapy. Patients and methods This retrospective study included 220 patients (152 females, 68 males; mean age 68 years) with ATC who were treated in our country from 1972 to 2017. The salt was iodinated with 10 mg of potassium iodide/ kg before 1999, and with 25 mg of potassium iodide/kg thereafter. The patients were assorted into 15-year periods: 1972-1986, 1987-2001, and 2002-2017. Results The incidence of ATC decreased after a higher iodination of salt (p = 0.04). Patients are nowadays older (p = 0.013) and have less frequent lymph node metastases (p = 0.012). The frequency of distant metastases did not change over time. The median survival of patients in the first, second, and third periods was 3, 4, and 3 months, respectively (p < 0.05). The history of RAI therapy was present in 7.7% of patients. Conclusions The number of patients with a history of RAI therapy did not change statistically over time. The incidence of ATC in Slovenia decreased probably because of higher salt iodination.

Preoperative Potassium Iodide Treatment in Patients Undergoing Thyroidectomy for Graves' Disease-Perspective of a European High-Volume Center.

BACKGROUND: Potassium iodide (KI) treatment affects the vascularity of the thyroid gland and therefore may improve intraoperative visualization of essential structures. However, clear evidence for its usage is lacking, and its implementation in patients suffering from Graves' disease is becoming rare. The objective of this retrospective study was to assess the impact of KI treatment on the intraoperative course and the outcome of patients undergoing thyroidectomy for Graves' diseases. METHODS: The study included 442 patients: 125 patients (28.3%) who received a preoperative treatment with KI ("Group KI") and 317 patients (71.7%) without a KI therapy ("Group No-KI"). Indication for KI treatment was a thyroid bruit (82.5%), as well as hyperthyroidism refractive to medical treatment with antithyroid drugs (17.4%). RESULTS: All patients underwent total thyroidectomy. Permanent vocal cord paresis and permanent hypoparathyroidism were similar in both groups. KI treatment was associated with a significantly longer operative time (142 vs. 128 min, p < 0.001) and a significant higher weight of the thyroid gland. KI treatment did not impact duration of hospital stay or occurrence of secondary hemorrhage. CONCLUSIONS: The complication rate of this study population with clinically severe GD was very low-which may be caused by pre-treatment of patients. The complementary option of a potassium iodide treatment before surgery remains a possibility and should be implemented individually.

Metabolomics evaluation of repeated administration of potassium iodide on adult male rats.

The long-lasting consequence of a new iodine thyroid blocking strategy (ITB) to be used in case of nuclear accident is evaluated in male Wistar rats using a metabolomics approach applied 30 days after ITB completion. The design used 1 mg/kg/day of KI over 8 days. Thyroid hormones remained unchanged, but there was a metabolic shift measured mainly in thyroid then in plasma and urine. In the thyroid, tyrosine metabolism associated to catecholamine metabolism was more clearly impacted than thyroid hormones pathway. It was accompanied by a peripheral metabolic shift including metabolic regulators, branched-chain amino acids, oxidant stress and inflammation-associated response. Our results suggested that iodide intake can impact gut microbiota metabolism, which was related to host metabolic regulations including in the thyroid. As there were no clear clinical signs of dysfunction or toxicity, we concluded that the measured metabolomics response to the new ITB strategy, especially in thyroid, is unlikely to reveal a pathological condition but a shift towards a new adaptive homeostatic state, called 'allostatic regulation'. The question now is whether or not the shift is permanent and if so at what cost for long-term health. We anticipate our data as a start point for further regulatory toxicity studies.

Nuclear power plant: state of knowledge of the population living in the area of the Cattenom special intervention plan. A cross-sectional study.

In France information campaigns are periodically conducted within a 10 km radius of nuclear power plants on the protective actions to be adopted in the event of a nuclear accident. The aim of this study was to assess the knowledge of the inhabitants of the Cattenom PPI area on the recommended actions to be adopted in the event of a nuclear accident after the information campaign that took place from 2016 to 2017 and compare its results with a similar study carried out before the information campaign. We performed a cross-sectional study in the Cattenom PPI area after the 2016-2017 information campaign. We administered questionnaires in ten municipalities selected by lot. These questionnaires contained queries on the general protective actions and required approach to taking potassium iodide (KI). The results obtained were compared with the results of a study conducted before the information campaign in the same area. Out of 200 questionnaires administered, 122 people responded. Only 40% of respondents remembered the information campaign. Only 16% knew all of the recommended protective actions. 78% of households had KI and only 60% knew the objective of KI intake. Compared to the results of the study before the information campaign, KI coverage was better (69% versus 78%, p = 0.02) and the dosage was better known (16% versus 28%, p = 0.0003). This study provides an overview of the effectiveness of information campaigns on the procedure in the event of a nuclear accident. This study highlights the insufficient knowledge of people living in the Cattenom PPI area.

Medical Therapy of Patients Contaminated with Radioactive Cesium or Iodine.

Follow-up studies after the Chernobyl and Fukushima accidents have shown that 137Cs and 131I made up the major amount of harmful contaminants in the atmospheric dispersion and fallout. Other potential sources for such radionuclide exposure may be terrorist attacks, e.g., via contamination of drinking water reservoirs. A primary purpose of radionuclide mobilization is to minimize the radiation dose. Rapid initiation of treatment of poisoned patients is imperative after a contaminating event. Internal contamination with radioactive material can expose patients to prolonged radiation, thus leading to short- and long-term clinical consequences. After the patient's emergency conditions are addressed, the treating physicians and assisting experts should assess the amount of radioactive material that has been internalized. This evaluation should include estimation of the radiation dose that is delivered and the specific radionuclides inside the body. These complex assessments warrant the reliance on a multidisciplinary approach that incorporates regional experts in radiation medicine and emergencies. Regional hospitals should have elaborated strategies for the handling of radiation emergencies. If radioactive cesium is a significant pollutant, Prussian blue is the approved antidote for internal detoxification. Upon risks of radioiodine exposure, prophylactic or immediate treatment with potassium iodide tablets is recommended. Chelators developed from calcium salts have been studied for gastrointestinal trapping and enhanced mobilization after strontium exposure.

Iodine bioavailability from cow milk: a randomized, crossover balance study in healthy iodine-replete adults.

BACKGROUND: Milk and dairy products are considered important dietary sources of iodine in many countries. However, to our knowledge, iodine bioavailability from milk has not been directly measured in humans. OBJECTIVE: The aim of this study was to compare iodine bioavailability in iodine-replete adults from: 1) cow milk containing a high concentration of native iodine; 2) milk containing a low concentration of native iodine, with the addition of potassium iodide (KI) to assess a potential matrix effect; and 3) an aqueous solution of KI as a comparator; with all 3 containing equal amounts of total iodine (263 µg/250 mL). We also speciated iodine in milk. DESIGN: We conducted a 3-wk, randomized, crossover balance study in adults (n = 12) consuming directly analyzed, standardized diets. During the 3 test conditions - high intrinsic iodine milk (IIM), extrinsically added iodine in milk (EIM), and aqueous iodine solution (AIS) - subjects collected 24-h urine over 3 d and consumed the test drink on the second day, with 3- or 4-d wash-out periods prior to each treatment. Iodine absorption was calculated as the ratio of urinary iodine excretion (UIE) to total iodine intake. Milk iodine speciation was performed using ion chromatography-mass spectrometry. RESULTS: Iodine intake from the standardized diet was 195 ± 6 µg/d for males and 107 ± 6 µg/d for females; the test drinks provided an additional 263 µg. Eleven subjects completed the protocol. There was a linear relation between iodine intake and UIE (ß = 0.89, SE = 0.04, P < 0.001). There were no significant differences in UIE among the 3 conditions (P = 0.24). Median (range) fractional iodine absorption across the 3 conditions was 91 (51-145), 72 (48-95), and 98 (51-143)% on days 1, 2, and 3, respectively, with day 2 significantly lower compared with days 1 and 3 (P < 0.001). In milk, 80-93% of the total iodine was inorganic iodide. CONCLUSION: Nearly all of the iodine in cow milk is iodide and although fractional iodine absorption from milk decreases with increasing dose, its bioavailability is high. The trial was registered at clinicaltrials.gov as NCT03590431.

Iodine supplementation of lactating women and assessment of infant visual information processing and maternal and infant thyroid function: A randomized trial.

Iodine deficiency is one of the major causes of brain damage in childhood. However, iodine supplementation during early pregnancy and lactation can prevent the ill effects of iodine deficiency. This study evaluated maternal and infant thyroid function and infant visual information processing (VIP) in the context of maternal iodine supplementation. A community-based, randomized, supplementation trial was conducted. Mother infant dyads (n = 106) were enrolled within the first 10 days after delivery to participate in this study. Mothers were randomly assigned either to receive a potassium iodide capsule (225 µg iodine) daily for 26 weeks or iodized salt weekly for 26 weeks. Maternal thyroxine (T4), triiodothyronine (T3), thyroid stimulating hormone (TSH), thyroglobulin (Tg), urinary iodine concentration (UIC), breast milk iodine concentration (BMIC) and infant T4, TSH, UIC and VIP were measured as outcome variables. At baseline, neither mothers nor infants in the two groups were significantly different in any of the biomarkers or anthropometric measurements. Maternal TSH and goiter prevalence significantly decreased following iodine supplementation. The percentage of infants who preferentially remembered the familiar face was 26% in the capsule and 51% in the I-salt groups. Infant sex, length for age Z score, BMIC, maternal education and household food security were strong predictors of novelty quotient. In conclusion supplementation daily for six months with an iodine capsule or the use of appropriately iodized salt for an equivalent time was sufficient to reduce goiter and TSH in lactating women. Higher BMIC and LAZ as well as better household food security, maternal education, and male sex predicted higher novelty quotient scores in the VIP paradigm.

A case of neutrophilic dermatosis with MEFV gene variant and abnormal activation of peripheral blood monocytes: a case report.

A healthy 32-year-old man had a fever and elevated levels of white blood cells (WBC) and C-reactive protein (CRP). In addition, he presented with a skin rash on his forehead, around the neck, and from the anterior chest to the abdomen. His laboratory findings showed elevated levels of hepatic enzyme, CRP, and ferritin; therefore, he was suspected to have adult-onset Still's disease (AOSD) and referred to our department. We ruled out hematological malignancy and established diagnosis of AOSD according to Yamaguchi's criteria and treated with 20 mg/day prednisolone. His clinical condition did not improve, therefore, we increased the dosage of prednisolone to 40 mg/day; however, his rash gradually expanded with papules and plaques. A cervical skin biopsy revealed neutrophil dermatosis and analysis of the MEFV gene revealed a heterozygous variant in exon 2 (E148Q). We found an elevated percentage of CD86+CD14+CD16- classical monocytes in the peripheral blood using flow cytometry. We added oral potassium iodide as a treatment for neutrophil dermatosis. Despite this treatment, his eruption and fever did not subside, therefore, we changed potassium iodide to colchicine, this improved his clinical condition. This case suggests the importance of autoinflammation-related gene abnormalities and macrophage activation in the pathogenesis of neutrophil dermatosis.

Cutaneous tuberculosis: A great imitator.

Tuberculosis (TB) is still prevalent in many developing countries and can pose a new potential threat to global health due to international migration. As an uncommon form of extrapulmonary TB, cutaneous TB is complicated in its clinical manifestation, pathogenesis, and classification. Cutaneous TB can be divided into two major categories, true cutaneous TB and tuberculid, depending on the source of infection, the route of transmission, the amount of bacteria, and the immune state of the host. Clinical manifestations may include patches and plaques (lupus vulgaris, TB verrucosa cutis), macules and papules (acute miliary TB, papulonecrotid tuberculid, lichen scrofulosorum), nodules, and abscesses (erythema induratum of Bazin, tuberculous gumma), erosions, and ulcers (tuberculous chancre, orificial TB, scrofuloderma), mimicking diverse skin diseases. Uncommon localizations such as external genitalia, unusual presentations such as nodular granulomatous phlebitis, and coexistence with other morbidities such as Behçet disease and acne inversa or hidradenitis suppurativa deserve special attention. Treatment of both true and tuberculid cutaneous TB follows the same drug regimens of the World Health Organization's recommendation for treatment of new cases of pulmonary TB. Erythema induratum of Bazin may need longer treatment duration and adjuvants such as dapsone, potassium iodide, doxycycline, and corticosteroids to tackle inflammation. Misdiagnosis and undertreatment in daily practice are likely, and contemplation of this classic great imitator in dermatology is warranted.

A systems biology approach to propose a new mechanism of regulation of repetitive prophylaxis of stable iodide on sodium/iodide symporter (NIS).

Our group showed that repetitive dose of potassium iodide (KI) for eight days offers an efficient protection for exposure to repeated radioactive emissions without adverse effects on adult rats. However, differential expression of genes implicated in Wolff-Chaikoff effect was observed. To understand the Wolff-Chaikoff regulation and its molecular constituents during repetitive administration of KI, a biochemical reaction network was constructed as a "geographical" map of the thyrocyte depicting iodide and thyroid hormone synthesis. Path analysis of the network has been performed to investigate the presence of a regulatory circuit of the node iodide to the node "nis transcription". NIS is responsible for the uptake of KI and plays an important role in the Wolff-Chaikoff effect. The map is a source for the most updated information about iodide and thyroid hormone metabolism. Based on this map, we propose a hypothesis that shows a putative mechanism behind NIS regulation and KI uptake.

Squamous cell carcinoma subsequent to scarring caused by sporotrichosis: A case report.

BACKGROUND: Sporotrichosis is a fungal disease caused by the Sporothrix schenckii species complex. It is usually acquired by trauma with plants. Lymphatic-cutaneous is the most common clinical manifestation. CASE REPORT: The present case describes the development of an epidermoid carcinoma as a late complication on a long evolution sporotrichosis scar. During a period of 50 years, the patient had lesions in the right hand. Sporotrichosis was diagnosed and treated with potassium iodide. Eleven years after the healing of the lesions, a squamous cell carcinoma on the scar of this mycosis was diagnosed. CONCLUSIONS: The chronic sporotrichosis injury was probably the cause of the tumor developed on the scar.

Microcomputed Tomography Evaluation of Root Dentin Caries Prevention by Topical Fluorides and Potassium Iodide.

The mineral content of dental hard tissues has traditionally been measured by destructive tests such as transverse microradiography. Microfocus X-ray computed tomography (micro CT) has enabled non-destructive 3D assessment of tooth demineralization. This study compared the preventive effects of silver diammine fluoride (SDF) and potassium iodide (KI) in comparison with fluoride varnish. SDF has been known to arrest caries but darkens the tooth. KI creates a precipitate with SDF that reduces the discoloration, but its effects on SDF efficacy in terms of preventing demineralization of at-risk root dentin surfaces is unknown. Bovine root dentin blocks were randomly distributed into four groups and subjected to a pretreatment in each group (n = 8); Control: deionized water (DIW); F-Varnish: 5% sodium fluoride varnish: 38% Saforide; SDF+KI: SDF followed by saturated solution of KI in DIW. The treated dentin was subjected to 8 cycles of demineralization (pH 5) for 14 h and remineralization in artificial saliva (pH 7) for 10 h. Specimens were then scanned for 12 min using micro CT at 73 KV and 1012 µA with 8.3 µm resolution. The 3D images were analyzed in Amira software to calculate lesion depth (LD), surface layer mineral density (SL) and mineral loss (ΔZ) for each specimen. One-way ANOVA with Bonferroni posthoc showed that there was a statistically significant difference between Control and all three other groups for all parameters (P < 0.001), however, there was no statistical difference among F-Varnish, SDF and SDF+KI (P > 0.05). Single application of F-Varnish, SDF and SDF+KI showed comparable preventive effects against root dentin demineralization. Application of KI did not affect anti-demineralization properties of SDF in this study. Micro CT is a quick and effective method for objective and high-resolution characterization of dentin caries lesions.

Effects of Preoperative Iodine Administration on Thyroidectomy for Hyperthyroidism: A Systematic Review and Meta-analysis.

OBJECTIVE: The current guidelines recommend that potassium iodide be given in the immediate preoperative period for patients with Graves' disease who are undergoing thyroidectomy. Nonetheless, the evidence behind this recommendation is tenuous. The purpose of this study is to clarify the benefits of preoperative iodine administration from published comparative studies. DATA SOURCES: We searched PubMed, Embase, Cochrane, and CINAHL from 1980 to June 2018. REVIEW METHODS: Studies were included that compared preoperative iodine administration and no premedication before thyroidectomy. For the meta-analysis, studies were pooled with the random-effects model. RESULTS: A total of 510 patients were divided into the iodine (n = 223) and control (n = 287) groups from 9 selected studies. Preoperative iodine administration was significantly associated with decreased thyroid vascularity and intraoperative blood loss. Significant heterogeneity was present among studies. We found no significant difference in thyroid volume or operative time. Furthermore, the meta-analysis showed no difference in the risk of postoperative complications, including vocal cord palsy, hypoparathyroidism/hypocalcemia, and hemorrhage or hematoma after thyroidectomy. CONCLUSION: Preoperative iodine administration decreases thyroid vascularity and intraoperative blood loss. Nonetheless, it does not translate to more clinically meaningful differences in terms of operative time and postoperative complications.