Clinical endodontic management during the COVID-19 pandemic: a literature review and clinical recommendations.

The spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in millions of confirmed cases and hundreds of thousands of deaths. Despite all efforts to contain the spread of the disease, the number of infections and deaths continue to rise, particularly in some regions. Given its presence in the salivary secretions of affected patients, and the presence of many reported asymptomatic cases that have tested positive for COVID-19, dental professionals, including Endodontists, are at high risk of becoming infected if they do not take appropriate precautions. As of today, there are no predictable treatments or approved vaccines that can protect the public and healthcare professionals from the virus; however, there is speculation that a vaccine might be available sometime in 2021. Until then, general dentists and Endodontist will need to be able to treat emergency patients in order to relieve pressure on emergency clinics in hospitals or local community hubs. In addition, as the pandemic continues, strategies to manage patients will need to evolve from a palliative to a more permanent/definitive treatment approach. In this article, an update on the treatment considerations for dental care in general is provided, as well as a discussion on the available endodontic guidelines reported in the literature. Recommendations on clinical management of endodontic emergencies are proposed.

Assessment of apical transportation caused by nickel-titanium rotary systems with full rotation and reciprocating movements using extracted teeth and resin blocks with simulated root canals: A comparative study.

OBJECTIVES: : We compared apical transportation in the WaveOne and ProTaper Next systems, which are rotary nickel-titanium systems with reciprocating and continuous rotation movements, respectively, using manual measurements obtained from resin blocks with simulated root canals and double digital radiographs of extracted teeth. MATERIALS AND METHODS: : We used 30 resin blocks with simulated root canals and 30 extracted teeth for this study. The same endodontist performed root canal shaping using the WaveOne or ProTaper Next system. We assessed apical transportation by measuring the amounts (in mm) of material lost 1 mm from the apical foramen in the resin blocks and by using double digital radiography for the extracted teeth. Significant differences between groups were assessed using t-tests. P < 0.05 was considered statistically significant. RESULTS: : The amount of apical transportation differed significantly between the two systems when resin blocks were used for assessment (P < 0.05), but there were no significant differences when extracted teeth were used (P < 0.05). CONCLUSIONS: In the current study, there was no significant difference in apical transportation between natural teeth prepared using WaveOne and those prepared using ProTaper Next. However, significant differences were observed between the two systems with resin blocks. These findings indicate that the use of resin blocks is not an accurate method for apical transportation evaluation.

Role of intraseptal anesthesia for pain-free dental treatment.

Pain control during the dental procedure is essentials and challenging. A complete efficacious pulp anesthesia has not been attained yet. The regional anesthesia such as inferior alveolar nerve block (IANB) only does not guarantee the effective anesthesia with patients suffering from irreversible pulpitis. This main aim of this review was to discuss various aspects of intraseptal dental anesthesia and its role significance in pain-free treatment in the dental office. In addition, reasons of failure and limitations of this technique have been highlighted. Literature search was conducted for peer-reviewed articles published in English language in last 30 years. Search words such as dental anesthesia, pain control, intraseptal, and nerve block were entered using a web of knowledge and Google scholar databases. Various dental local anesthesia techniques were reviewed. A combination of block anesthesia, buccal infiltration and intraligamentary injection resulted in deep anesthesia (P = 0.003), and higher success rate compared to IANB. For pain-free management of conditions such as irreversible pulpitis, buccal infiltration (4% articaine), and intraosseous injection (2% lidocaine) are better than intraligamentary and IANB injections. Similarly, nerve block is not always effective for pain-free root canal treatment hence, needing supplemental anesthesia. Intraseptal anesthesia is an efficient and effective technique that can be used in maxillary and mandibular adult dentition. This technique is also beneficial when used in conjunction to the regional block or local dental anesthesia.

Primary polydipsia. Syndrome of inappropriate thirst.

A patient with lifelong severe polyuria and polydipsia had normal serum antidiuretic hormone (ADH) levels and responded to water deprivation with a prompt increase in urine osmolality and maintenance of normal plasma osmolality (less than 290 mOsm/kg), despite extreme thirst. When treated with desmopressin acetate and allowed free access to water, she was able to reduce plasma osmolality below 270 mOsm/kg, and her compelling thirst disappeared. The disorder is interpreted to be the result of excessive fluid intake in response to a thirst stimulus that was not inhibited by normal plasma osmolality. This study indicates that osmoreceptor control of ADH secretion is normal. Continued administration of vasopressin has relieved the symptoms and has not resulted in water intoxication.

Failure of angiotensin II to stimulate increases in concentrations of adrenal androgens, 17-hydroxyprogesterone, or adrenocorticotropin in congenital 21-hydroxylase deficiency.

To determine if angiotensin II stimulates an increase in the plasma concentration of androstenedione, dehydroepiandrosterone, 17-hydroxyprogesterone, or ACTH in a patient with congenital 21-hydroxylase deficiency, we measured these plasma concentrations before and after the plasma angiotensin II concentration was increased by upright posture and angiotensin II infusion in a surgically castrate XX adult patient with this disorder. The patient was studied before treatment, after treatment with 1 mg dexamethasone daily for 3 weeks, and after treatment with both dexamethasone and 0.2 mg fludrocortisone daily for 3 weeks. The plasma concentrations of androstenedione, dehydroepiandrosterone, and 17-hydroxyprogesterone did not change consistently during increases in the angiotensin II concentration. The ACTH concentration did not increase in response to raised angiotensin II concentrations before or after steroid treatment. During the infusion of angiotensin II, blood pressure increased and renin activity decreased appropriate in degree to the preinfusion concentration of angiotensin II. The results from the study of this patient do not support the hypotheses that in congenital 21-hydroxylase deficiency, angiotensin II directly stimulates adrenal androgen secretion or that angiotensin II stimulates ACTH secretion.

Pituitary carcinoma mimics the ectopic adrenocorticotropin syndrome.

A middle-aged man presented with weight loss, hypokalemic alkalosis, diabetes, hypertension, and generalized melanosis. Marked elevation of urinary free cortisol (655 micrograms/24 h) and plasma ACTH (2445 PG/ML) SUGGESTED THE DIAGNOSIS OF ECTOPIC ACTH syndrome. The plasma concentrations of cortisol and urinary 17-hydroxycorticosteroids increased paradoxically during the administration of dexamethasone without a corresponding change in the plasma ACTH level. Metyrapone administered over 24 h also markedly incrased both urinary free cortisol and 17-hydroxycorticosteroids. Selective venous sampling of plasma ACTH did not reveal a gradient between jugular vein and peripheral venous blood. The laboratory findings supported the diagnosis of ectopic ACTH syndrome. However, belated occurrence of visual changes necessitated surgical exploration, resulting in the diagnosis of pituitary carcinoma. A fluorescent antibody to ACTH reacted strongly with the atypical pituitary cells. This rare case documents that severe melanosis in Cushing's disease can occur without prior adrenalectomy and is consistent with the diagnosis of pituitary carcinoma. Furthermore, melanosis observed in patients with pituitary carcinoma is associated with ACTH levels similar to those occurrring in the ectopic ACTH or Nelson's syndrome.

Evaluation of thyroid function during growth hormone therapy.

Decrease in the blood levels of PBI, in the thyroidal uptake of iodine, and diminished effect of TRH on TSH release have been reported to occur during growth hormone administration. We assessed thyroid function indices in two groups of growth hormone deficient children before and during long-term HGH therapy. Eight patients were given TSH prior and at 2, 4, and 6 mo of growth hormone treatment. In four other children, the disposal rates of simultaneously administered I125-T4 and I131-T3 were measured before and at 2 and 6 mo after initiation of HGH replacement. Blood levels of TSH, T3, T4, TBG capacity, and the T3 resin uptake were obtained at the time of each study. Growth hormone therapy did not affect the blood levels of T4, T3, TSH, TBG capacity, the T3 resin uptake, the thyroidal response to exogenous TSH, nor the disposal rates of thyroid hormones.

Origin and subsurface history of geothermal water of Murtazabad area, Pakistan--an isotopic evidence.

The Murtazabad area represents one of the major geothermal fields in Pakistan, with seven hot springs lying along the Main Karakoram Thrust. Discharge of the springs is 50-1200 l per minute with the surface temperature from 40 to 94 degrees C. Environmental isotopes and chemical concentrations have been used to investigate the origin and subsurface history of thermal water. Four sets of water samples were collected and analyzed for various isotopes including 18O, 2H and 3H of water; 34S and 18O of dissolved sulphates and chemical contents. Isotopic and chemical data show that the origin of thermal water is meteoric water. On the delta-diagram, delta18O and delta2H data plotting below the local meteoric water line with a slope around 12.3 show that the original thermal water receives recharge from precipitation at higher altitude (3000 m) and undergoes delta18O shift of about 1 per thousand due to exchange with rocks. Different correlations between isotopes, temperature and Cl indicate that the observed isotopic compositions have evolved due to mixing of different proportions of shallow water at different spring paths during movement of thermal water towards the surface. It is also inferred from the tritium data along with delta18O and delta2H that the circulation time is long and is estimated to be more than 50 years.

Intracranial metastasis from medullary carcinoma of the thyroid 25 years after primary surgery.

Medullary carcinoma of the thyroid is an uncommon tumour. In most patients, it is confined to the neck with or without involvement of the local cervical nodes. It rarely metastasizes to the mediastinum, lungs or liver. Intracranial metastasis is extremely rare with very few reported cases in the literature. We report an unusual case of an intracranial metastasis from a medullary carcinoma of the thyroid that occurred 25 years after primary surgery. We discuss the unusual features of our case together with a review of the literature.

Effect of storage on the prevalent alum-precipitated hemorrhagic septicaemia vaccine in Pakistan and preparation of a more efficient oil adjuvant vaccine using dense culture of Pasteurella multocida Roberts type 1 on an improved culture medium.

Significantly drastic effects of storage on the potency of the alum-precipitated haemorrhagic septicaemia (APHS) vaccine are reported. The APHS vaccine, studied through challenge infection of vaccinated rabbits (post-60 days of vaccination), showed 100% potency when stored at 4 degrees C for 30 days. The potency dropped to 20% when storage period was extended to 60 or more days. At 30 degrees C, the potency reduced by 40, 40 and 60%, respectively, after 30, 60 and 90 days of storage, while, at 37 degrees C, the decrease was 60, 60 and 100% after 30, 60 and 90 days of storage, respectively. In view of this, the oil-adjuvant (OA) HS vaccine was developed by culturing Pasteurella multocida on a medium comprising yeast extract, sucrose, trypticase and sodium bicarbonate, under continuous aeration at 37 degrees C. This gave a far better bacterial count (maximum count 15 x 10(8)/ml) than the conventional APHS vaccine (maximum count 6 x 10(8)/ml). The OAHS vaccine-carrying water-in-oil emulsion remained stable at room temperature for 1 year. The log protection values of the two batches of the OAHS vaccine, studied in mice, were 5.2 and 5.3, as against 1.9 of the APHS vaccine.