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Radiologic evaluation begins with Turkey buy cheap aciclovir 400 mg line, 3Gülhane Military Medical Academy generic 800mg aciclovir otc, Physical Medicine a plain radiograph of the symptomatic site order aciclovir 200mg mastercard. Osteolytic or sclerotic and Rehabilitation, Ankara, Turkey lesions may be seen on X-ray graphy. The patient having de- generative changes on lumbosacral x-ray graphy was considered to be affected by sacroiliitis and a whole-body bone scintigraphy 238 was requested. The chronic pain was correlated with both disease-related and the likely causes are hormonal changes and edema. Common factors such as rigidity and daily living activities and also general treatment options are activity modifcation, splinting, steroid injec- factors such as gender and depression. Symptoms were worse at night and she also complained of sleep disturbance because of pain. Motor and sensory examination of both Umay 1Ministry of Health Ankara Diskapi Yildirim Beyazit Education and upper limbs was normal. Results: Signifcant reduc- partment of Physical Therapy and Rehabilitation, Ankara, Turkey tion in pain and recovery of sleep disturbances noted and it was continiued from the day after the frst session to delivery. Conclu- Introduction/Background: Although musculoskeletal problems are sion: In recent years kinesio-taping has become popular in muscu- common, there have been few reports that describe the prevalence loskeletal problems. This technique also relieves pressure and irritation lence of musculoskeletal pain and its impact on activities of daily of the neurosensory receptors that can create pain. Leblebici1 and motor complications, comorbid conditions, and health-related 1Baskent University, Physical Medicine and Rehabilitation, Adana, quality of life were evaluated and recorded. Pain lasting longer than Turkey three months was defned as ‘chronic pain’ and participants were questioned relative to the characteristics of the chronic pain. Results: There was no statistically signifcant cor- J Rehabil Med Suppl 55 Poster Abstracts 75 relation between age and the risk of fall. Also, it was not determined infammatory arthritis and as an evaluation of the temperomandibu- the signifcant correlation between the values of latency and ampli- lary joint, it is however a new method for objective pain evaluation. Material and Methods: In inten- may be not alone signifcant factor for the risk of fall. Thir- measurements may not be provide a signifcant contribution to evalu- teen (n=9. Our participants can be considered as pain of the retinaculum patellae and were included in this study. It is thought to work by underlining that there may be a 90 degrees and 45 degrees. Results: The temperature differences risk of falling more than expected in the community. To our knowledge, this is the frst 1 2 3 report of an objective assessment of pain of the retinaculum patel- M. Our fndings could help making it Shiraz University of Medical Sciences, Physical Medicine and Re- possible to localize and assess pain more precisely. We suppose distal crease of the ance obtained from the electrode applied to the hand was measured, wrist as a point of no. The patients with omalgia and the low back pain in para- tween each two points, and each segments between each 2points lyzed side were done the hyperthermia of hot pack and the xylocaine are called 1to7 from proximal to distal. Results: Mean age of par- intramuscular injection, and visual analogue scale was compared ticipants was 45. Results: For of distal sensory latency (both antidromic and orthodromic) with the patients with omalgia and the low back pain, the difference was inching method are greater in patients than control group (p-value admitted in the individual value that was able to be put in the resting <0. Conclusion: We reveal signifcant difference of antidro- the improvement of the pain sensation was, the smaller increases of mic sensory latency between two adjacent points belonged to ffth impedance when the low back pain was improved by the effect of and sixth segments. Conclusion: The pain is a subjective phenomenon, latency between points was greater in patients than control group and it is changeable. The objective evaluation is diffcult because but only sixth segment had statistically signifcant difference. Kimura, and electromyography was bell’s type facial nerve palsies were compared in 5 years interval performed with monopolar needle electrode 1 inch and a half in The presence or absences of spontaneous activities in orbicularis the muscle bellies. In each patient the perception of pain was as- oculi or frontals muscles were considered. Results: The results showed the following: volved sites and normal sites in each patient calculated. Finally the The perception of pain was much higher during the nerve conduc- data of two groups were compared statistically. Results: Only in 25% of patients Conclusion: Nevertheless, the pain perceived in both tests was with Bell’s palsy the spontaneous activities were recorded while high, considering this kind of tests as painful and invasive tests it was recordable in all trauma patients at p=0. Material and Methods: 3 month retrospective study of inpatients 1Ahvaz Jundishapur Univeristy of Medical Scineces - Ahvaz - Iran, from Apr–Jun 2015 (n=25). The study end point was either pa- Physical Medicine and Rehabilitation, Ahvaz, Iran, 2Ahvaz Jundis- tient discharge or optimised analgesia. We captured demographic hapur Univeristy of Medical Scineces - Ahvaz - Iran, Neurology, data, injuries/treatments nature, and pain scores at admission and Ahvaz, Iran, 3Ahvaz Jundishapur Univeristy of Medical Sciences discharge/end points. Data displayed as median (range) unless - Ahvaz - Iran, Health Research Center- Diabetes Research Center- otherwise stated. Pain scores tend to improve and Introduction/Background: Most of the post stroke patients suffer analgesia use tended to decrease over time. Discussion: We described the with the method of including stretching exercises in addition to dis- profle, pain prevalence, and use of analgesia in rehabilitation pa- port injection in the affected muscles. Majority of patients come from surgical specialties, and ex- number of eight hemiplegic patients following their middle cerebral perience a combination of pain caused by their initial insult and/ artery embolism divided in two identical groups. Patients tended to be pain-free at study disport injected in their involve muscles and for the second group endpoint. Their analgesics rationalised and optimised, leading to the stretching exercises was added to their shoulders, elbows, wrist reduce usage by endpoint. This reduced analgesia supports im- and fnger fexors in addition to the treatment plan for the frst group. Conclusion: Rehabilitation pa- ity were compared using Mann-Withney test after 8 weeks. We have shown that our patients There was a signifcant improvement in upper limb spasticity in the have demonstrably reduced pain scores, optimised and typically second group in compare with the frst group at p<0. This may refect a com- The present study reveals the disport injection did not exclude the bination of a rationalised approach to analgesia, and therapeutic need for upper limb stretching exercises in studied group. Limitations: This study was retrospective, and small sample size (subgroup analyses were 249 not possible). Uğurlu2 1Muğla Sıtkı Koçman University- Faculty of Medicine, Physical Introduction/Background: Hand grip disability is a common dis- 2 order among Patients suffering from spasticity and weakness af- Medicine & Rehabilitation, Muğla, Turkey, Yıldırım Beyazıt Uni- ter traumatic brain injuries. The aim of this study was to compare versity- Faculty of Medicine, Physical Medicine & Rehabilitation, the Effect of Three methods of treatments. They were divided to three groups consisted of fve resulting in the mosaic pattern to the lameller bone. Their Glasgow coma score at hospital admis- terised by focal abnormalities of increased bone turnover affecting sion time were 3–6. The their limbs spasticity and abilities to hold and carrying a ball dur- pain character was mechanical produced by walking and resolved ing the treatments method were compared using non parametric by rest. He had antalgic posture because of decreased spinal mo- and chi square statistical tests. He had also limitation and pain during lumbar spine motion ments leaded to decrease patients limbs spasticity (p<0. Besides straight leg-raising test was hand grip ability improved in the 2nd and 3rd groups. On the other hand, he had local tenderness there was not any advantage in using tizanidin or disport in this over the lumbar spine. Conclusion: In order to gain a normal hand grip function There was no abnormality on neurological and systemic examina- not only the spasticity should be treated but also the other deter- tion except above fndings. There was also moth-eaten radiolucent minants such as weakness and patients insights and co-operation appearance on vertebral corpus of bone. Tecnetium bone scan demonstrated an increased 250 radioactive isotope uptake activity in the lumbar (L2–5) vertebras. Repeat radionuclide bone scanning 1Bolton, United Kingdom was signifcantly showed the reduced distrubition of affected bones. Patients with mild to moder- bones mimicking lumbar discopaty with neuropatic pain.

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Contraindications and drug interactions (1) Heparin is contraindicated in patients who are bleeding (internally or externally) and in patients with hemophilia generic aciclovir 200 mg line, thrombocytopenia buy discount aciclovir 200mg on line, hypertension purchase aciclovir 200 mg otc, or purpura. Fondaparinux is a synthetic polysaccharide based on the antithrombin-binding region of heparin. Administered by subcutaneous injection, it behaves like the low-molecular-weight heparins in inactivating factor Xa. Fondaparinux is approved for prophylaxis of thrombus formation in patients undergoing hip or knee surgery, treatment of pulmonary embolism, and deep vein thrombosis. Structure (1) Coumarin derivatives are derived from 4-hydroxycoumarin and include dicumarol, warfarin sodium, and phenprocoumon. Continued production of functional clotting factors requires replenishment of reduced vitamin K from the oxidized form; this reduction is catalyzed by vitamin K epoxide reductase; which is directly inhibited by coumarin derivatives. Therapeutic uses (1) The therapeutic uses of coumarin derivatives are similar to those of heparin; they also include treatment and prophylaxis of venous thrombosis and of pulmonary embolism. Coumarin derivatives are also indicated to reduce thromboembolism in patients with mechanical heart valves. Adverse effects (1) Bleeding is a common adverse effect with oral anticoagulants; prothrombin times should be frequently monitored. Warfarin causes defects in normal fetal bone formation; its teratogenic potential is high. Drug interactions (1) Amiodarone and sulfinpyrazone inhibit metabolism of the more active warfarin stereo- isomer and increase drug activity. Hirudin, a protein found in the saliva of the medicinal leech, directly binds to and inhibits thrombin in the circulation and within clots. Bivalirudin (Angiomax) is a synthetic 20-amino-acid peptide hirudin analogue; desirudin and lepirudin are recombinant hirudin analogues made in yeast. Lepirudin is approved for anticoagulation in patients with heparin-induced thrombocytopenia. Argatroban and lepirudin are synthetic inhibitors of thrombin and are derived from arginine. They are useful in the management of patients at risk for heparin-induced thrombocytopenia B. Vitamin K2is found in human tissues and is the form synthe- sized by intestinal bacteria. Administration of vitamin K to newborns reduces the incidence of hypothrombinemia of the newborn, which is especially common in premature infants. It is infrequently used in some anemias and refractory idiopathic thrombocytopenic purpura. Aminocaproic acid (1) Aminocaproic acid is a synthetic agent similar in structure to lysine. Aspirin and aspirin-like agents decrease thromboxane A2 production in platelets by inhibi- ting cyclooxygenases type 1. Low doses may impair prostaglandin synthesis in platelets to a greater extent than in endothelial cells and avoid this effect. Dipyridamole inhibits the cellular uptake of adenosine, which has vasodilating and antiag- gregating activity. The use of dipyridamole as an antithrombotic agent is limited to prophylaxis (with warfarin) in patients with prosthetic heart valves. Maximal effects are seen after several days of therapy; effects persist several days after treatment. Anagrelide (Agrylin) is an antithrombopenic agent that inhibits megakaryocytes for treatment of patients with thrombocythemia. Abciximab is the Fab fragment of a chimeric monoclonal antibody that contains human and mouse IgG components. The most common adverse effect is bleeding, especially if used in combination with heparin. These agents are plasma volume expanders that reduce erythrocyte aggregation and impair fibrin polymerization and platelet function in vivo by an unclear mechanism. Adverse effects include respiratory distress, urticaria, and (rarely) anaphylaxis. Inactive plasminogen is converted to plasmin in vivo by peptides called tissue plasminogen activators. The increase in half-life permits administration as a bolus rather than by continuous infusion. Streptokinase is a nonenzyme protein that is isolated from streptococci; it binds to plasmin- ogen to catalyze the conversion of plasminogen to active plasmin. Many individu- als have antistreptococcal antibodies because of prior exposure to the bacteria; this can reduce effectiveness and complicate treatment. Although streptokinase is commonly used in Europe, it is no longer marketed in the United States. Urokinase is a protease originally isolated from urine; the drug is now prepared in recombi- nant form from cultured kidney cells. It is less antigenic than streptokinase and is indicated in patients sensitive to streptokinase. A patient is admitted to the hospital for gall- constant abdominal pain, nausea, and short- bladder surgery, and although the surgery is ness of breath. A young couple present to their primary (E) Folic acid care physician stating that they are trying to conceive. A man undergoing chemotherapy for lung future mom-to-be needs to be on any cancer complains of shortness of breath when supplements. Which of the following women develop iron deficiency anemia would be most appropriate for this patient? A 65-year-old diabetic man develops end- peripheral vision and dizziness that lasts for stage renal disease. A 53-year-old obese woman is brought into stored in the body the emergency room by her concerned husband (E) It participates in the mitochondrial reaction approximately 1 hour after complaining of that produces succinyl-CoA 186 Chapter 7 Drugs Used in Anemia and Disorders of Hemostasis 187 7. He states that since he does not have alcohol abuse presents to the urgent care medical insurance, he only comes to see a doc- clinic complaining of lightheadedness and tor when he experiences these ‘‘crises. His laboratory studies pain medication is the emergency physician indicate a low hemoglobin level. A 74-year-old woman who is undergoing (E) Folic acid chemotherapy for advanced lung cancer presents to the infusion center for her next 8. Before each treatment her white goes gastric bypass surgery to help her lose count, hemoglobin, and platelet counts are weight. Her surgeon reminds her that now she checked to make sure she is not experiencing will have to get a monthly injection of vitamin chemotherapy-related cytotoxicity. Her blood B12, since the part of her stomach responsible sample is run in the analyzer, and her platelet for production of intrinsic factor has been count is reported to be at a dangerously low removed. A 55-year-old woman undergoes an open (E) Neurologic deficits are not seen with this cholecystectomy. She is admitted for postopera- kind of anemia tive observation and started on subcutaneous heparin treatment to prevent formation of deep 9. A 31-year-old pregnant woman presents to venous thrombosis, a major risk factor for pul- her obstetrician for a routine visit. Which of the following is eral questions for her doctor, one of which has true regarding the mechanism of action of to do with the supplements that she was advised heparin? She stated she (A) Heparin increases activity of antithrombin leads a very busy lifestyle and sometimes forgets (B) Serine proteases of the clotting cascade are to take all the pills she is supposed to take. She deactivated wants to know the purpose of folic acid supple- (C) Heparin catalyzes clotting in vitro mentation in pregnancy. A 63-year-old man has a history of atrial fi- (C) It aids in bone growth of the maturing fetus brillation. To reduce his risk of a stroke, his phy- (D) It stimulates myelopoiesis of erythroid pro- sician had given him an anticoagulant genitor cells medication. This agent, while being of tremen- (E) It reduces blood viscosity during pregnancy dous benefit to this patient, comes with its asso- ciated risks, such as spontaneous hemorrhage. A 29-year-old African-American man To monitor the appropriateness of the current presents to the emergency department with a dosage of the medication, the patient comes in chief complaint of severe pain in his arms and frequently to have the laboratory check his pro- legs.

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A semilogarithm plot is used for the concentration at each time point and this yields a linear configuration to the elimination plot buy aciclovir 400 mg with mastercard. Extrapolation of the semilogarithm elimination plot to time-zero permits calculation of the volume of distribution (Vd) of the drug in this specific set of clinical circumstances generic aciclovir 800mg otc. The volume of distribution equals the total dose of drug given (D) divided by 6 the time-zero theoretical concentration (T0) buy cheap aciclovir 800 mg, or D/(T0) ¼ Vd. Thus, 1 g of an antibiotic (1 Â 10 mg) with an extrapolated (T0) ¼ 50 m/mL results in a Vd ¼ 20,000 m, or 20 L. The linear configuration of drug elimination over time permits calculation of the biological elimination half-life (T1/2). The T1/2 is the period of time required for the equilibrated plasma concentration of the drug to decline by 50%. The expectation is that the plasma concentration reflects the dynamic processes of equilibration of the central pool (i. Antibiotics are generally considered to have a single T1/2 that describes elimination of the drug, but some may have a second T1/2 that describes clearance at low concentrations. Antibiotic Kinetics in the Multiple-System Trauma Patient 523 Figure 1 Illustrates the clearance curve of a theoretical antibiotic. Vd is a theoretical calculation that can be influenced by factors other than the actual body water of drug distribution. Knowledge of the Vd and T1/2 allows the design of dose and dosage intervals for the antibiotic. If our theoretical drug in Figure 1 was deemed to have toxicity at concentrations above 80 m/mL then it would be desirable to have the concentration below that threshold for the treatment interval. Thus, a rational configuration of the use of this drug would be a 1 g dose that was re- dosed every eight hours. Antibiotics with a significant post-antibiotic effect can have treatment intervals that are greater than would be predicted by the above model. Nevertheless, the above strategy is generally used for the design of the therapeutic application of drugs in clinical trials. The design is derived from studies in healthy volunteers and clinical trials are generally performed in patients without critical illness. Biotransformation is the process by which the parent drug molecule is metabolized following infusion. Biotransformation may occur via a number of pathways, although hepatic metabolism is most common. It may occur within the gastrointestinal tract, the kidney epithelium, the lungs, and even within the plasma itself. Hepatic biotransformation may result in the metabolite being released within the blood, resulting commonly in attenuation of action and facilitation of 524 Fry elimination via the kidney. Hepatic metabolism may result in the inactivated metabolite being eliminated within the bile. Clearly, abnormalities within the organ responsible for biotransformation will affect the process. The cytochrome P-450 system requires molecular oxygen, so poor perfusion or oxygenation of the liver from any cause will impact hepatic metabolism of specific drugs. Some drugs are eliminated unchanged by the kidney into the urine, or excreted by the liver into the bile. Excretion of unchanged drug via the biliary tract, which in turn can be reabsorbed, may create an enterohepatic circulation that results in prolonged drug presence in the patient. When either the intact drug or metabolic product is dependent on a specific organ system for elimination, intrinsic disease becomes an important variable in the overall pharmacokinetic profile. Extensive torso and extremity injuries result in soft tissue injuries that activate the human systemic inflammatory response. This systemic inflammatory response requires extensive volume resuscitation for maintenance of intravascular volume and tissue perfusion. Blunt chest trauma requires intubation and prolonged ventilator support, and exposure of the lung to environmental contamination. The patients are immunosuppressed from the extensive injuries, transfusions, and protein-calorie malnutrition. Following the injury itself, infection becomes the second wave of activation of systemic inflammation. Infection becomes a complication at the sites of injury, at the surgical sites of therapeutic interventions, and as nosocomial complications at sites remote from the injuries. Fever and hypermetabolism are common and add an additional compounding variable at a time when antimicrobial treatment is most important in the patient’s outcome. Antibiotics are invariably used in the febrile, multiple-injury patient, but they are dosed and re-dosed using the model of the healthy volunteer initially employed in the development of the drug. Are antibiotics dosed in accordance with the pathophysiologic changes of the injury and febrile state? Extensive tissue injury and invasive soft-tissue infection share the common consequence of activating local and systemic inflammatory pathways. The initiator events of human inflammation include (i) activation of the coagulation cascade, (ii) activation of platelets, (iii) activation of mast cells, (iv) activation of the bradykinin pathway, and (v) activation of the complement cascade. The immediate consequence of the activation of these five initiator events is the vasoactive phase of acute inflammation. The release of both nitric oxide–dependent (bradykinin) and independent (histamine) pathways result in relaxation of vascular smooth muscle, vasodilation of the microcirculation, increased vascular capacitance, increased vascular permeability, and extensive movement of plasma proteins and fluid into the interstitial space (i. The expansion of intravascular capacitance and the loss of oncotic pressure mean that the Vd for many drugs will be expanded. Shock, injury, and altered tissue perfusion have been associated with the loss of membrane polarization, and the shift of sodium and water into the intracellular space. At a theoretical level, there is abundant reason to anticipate that the conventional dosing of antibiotics may be inadequate in these circumstances (Fig. The vascular changes in activation of the inflammatory cascade also result in the relaxation of arteriolar smooth muscle and a reduction in systemic vascular resistance. The reduction in systemic vascular resistance becomes a functional reduction in left ventricular afterload, which combined with an appropriate preload resuscitation of the severely injured patient leads to an increase in cardiac index. The hyperdynamic circulation of the multiple- trauma patients leads to the “flow” phase of the postresuscitative patient. Increased perfusion of the kidney and liver results in acceleration of excretory functions and potential enhancement Antibiotic Kinetics in the Multiple-System Trauma Patient 525 Figure 2 Illustrates the influence upon the clearance curve of the theoretical antibiotic in Figure 1 of an increase in extracellular and/or intracellular water in a trauma patient that has fever secondary to invasive infec- tion. The peak concentration [A ]* and the equilibrated peak concentration [B ] are less* than those concentrations observed under normal circumstances. Subsequent organ failure from the ravages of sustained sepsis results in impairment of drug elimination and prolongation of T1/2. Severe injury results in the infiltration of the soft tissues with neutrophils and monocytes as part of the phagocytic phase of the inflammatory response. Proinflammatory cytokine signals are released from the phagocytic cells, from activated mast cells, and from other cell populations. The circulation of these proinflammatory signals leads to a febrile response with or without infection. The febrile response is associated with systemic hypermetabolism and autonomic and neuroendocrine changes that further amplify the systemic dyshomeostasis. Pro-inflammatory signaling up-regulates the synthesis of acute-phase reactants and down- regulates the synthesis of albumen, which further impacts the restoration of oncotic pressure and predictable drug pharmacokinetics. The summed effects of injury, fever, and the sequela of systemic inflammation result in pathophysiologic alterations (Table 1) that compromise the effectiveness of antibiotic therapy because of suboptimal dosing. A review of the literature identifies a paucity of clinical studies in the 526 Fry multiple-injury patient, despite the fact that antibiotics are used for a wide array of indications in these patients. The effects of pathophysiologic changes upon antibiotic therapy will be cited among studies of critically ill and severely septic patients in the intensive care unit, and not exclusively in multiple-trauma patients. Preventive Antibiotics in the Injured Patient Preventive antibiotics have been used for over 30 years in trauma patients (1). The recognized principals of preoperative administration of an antibiotic with activity against the likely pathogens to be encountered have been the hallmark of utilization in this setting. However, trauma patients have blood loss and large volumes of resuscitation in the period of time leading up to, and during, the operative intervention. The sequestration of the resuscitation volume into injured tissue results and the obligatory expansion of the extracellular water volume all contribute to a vastly expanded Vd. In a limited number of preliminary-study patients, they noted that conventional doses of 7. The explanation for the lower antibiotic concentrations in the conventional dosing regimen was found in the larger Vd and short T1/2 that were seen in the trauma patients compared to normal controls.

Key Point Fissure sealants reduce caries incidence but must be carefully monitored and maintained 400mg aciclovir. The clinician must assess the risk factors for that tooth developing pit or fissure caries buy 800 mg aciclovir amex. As a general guide to who will benefit buy aciclovir 200 mg mastercard, review the British Society for Paediatric Dentistry Policy Document (Nunn et al. Children and young people with medical, intellectual, physical, and sensory impairments, such that their general health would be jeopardized by either the development of oral disease or the need for dental treatment. In such children all susceptible sites in both the primary and permanent dentitions should receive consideration. All susceptible sites on permanent teeth should be sealed in children and young people with caries in their primary teeth (dmfs = 2 or more). Where occlusal caries affects one permanent molar, the operator should seal the occlusal surfaces of all the other molars. If the anatomy of the tooth is such that surfaces are deeply fissured, then these should be sealed. Where potential risk factors, such as dietary factors or oral hygiene factors, indicate a high risk of caries, then all sites at risk should be sealed. Where there is a doubt about the caries status of a fissure or it is known to have caries confined to the enamel, fissure sealants may be used therapeutically. After application, it is essential to monitor the surface both clinically and radiologically. Sealant use must be based on personal, tooth, and surface risk, and the clinician must assess these risks since it might change at any time in the life of the patient. So whereas it was traditionally stated that dentists should complete sealant application up to a year or two after eruption, he or she should assess the potential risk factors regularly, and place the sealant, when indicated irrespective of age. Failure rates are higher when sealants are placed on newly erupted teeth and in mouths with higher previous caries experience. Monitoring the integrity of sealant is vital in those circumstances and any deficiencies in a sealant should be corrected (Figs. The very small operculum of gingival tissue can be held away from the tooth gently with a flat plastic. Although some studies have confirmed these claims, the authors feel that this is an unnecessary extra procedure to subject the child to, and do not recommend it. Etching All the methods of cleaning the tooth, discussed above, should be accompanied with etching of the enamel surface. Etching for just 20 s with a range of concentrations of acid but most often, 35-37. Its one drawback is the susceptibility of the etched surface to saliva or moisture contamination, which reduces the bond strength. Salivary contamination results in significantly reduced bond strengths unless removed by thorough washing. Re-etching of the surface is usually necessary if salivary contamination has occurred. Bonding agents Bonding agents used as an additional layer under a resin sealant yield bond strengths significantly greater than the bond strength obtained when using sealant alone. Initial results of clinical trials also show increased retention of the sealant when an intermediate bond is used. New bonding techniques are proving to be less technique sensitive, with respect to moisture control than erstwhile procedures. The use of a bonding agent under a sealant on wet contaminated surfaces yields bond strengths equivalent to the bond strength obtained when sealant is bonded directly to clean etched enamel without contamination. Most of the data on the subject of using a bonding agent as part of the sealant procedure supports its use. Use of a bonding agent would tend to increase the time and cost of the sealant application but in cases where maintaining a dry surface is difficult or where there are areas of hypomineralization on the surface, it would have many advantages. Logically, combination of these technologies to achieve better penetration with less steps in the application sequence would be beneficial and there is some evidence already in the use of self-etching primer-adhesive systems. As yet, there has only been a 2-year follow-up but the early results are promising in relation to retention. Other studies have shown that there are concerns about micro-leakage compared with conventional acid etching. The big bonus of the self-etching primer-adhesive system is the speed with which the operator can apply it. In the application procedure for the Prompt-L-Pop system, the operator brushes the self-etching adhesive on to the surface; air thins it, and follows this by immediate placement of the sealant and polymerization. At present, therefore, there are conflicting views on these systems but with technology moving ever onwards it does seem likely that in the future it should be possible to achieve good etching and bonding with a simpler application method. Most clinicians will employ a resin-based sealant, because they have a good track record. Many clinical trials have demonstrated the effectiveness of resin sealants and there are several long-term studies, which show the benefits. Fifteen years after a single application, resin sealants have shown 28% complete retention of sealants and 35% partial retention on first permanent molars. Where researchers re-applied sealant to those surfaces that had deficient sealant as determined by yearly exams, 65% complete retention was obtained and only 13% of the surfaces had caries or restorations after 20 years. Retreatment Sealants placed in the first permanent molars in children of ages 6, 7, and 8 and in second permanent molars in children of ages 11 and 12 required more re-application than those placed in older teeth. If the clinician places fissure sealant in newly erupted teeth it is more likely to fail, but should still be placed as early as possible, because the teeth are more vulnerable to caries at this time. However, fluoride release occurs only for a very short time and at a very low level. Many studies over 2- 3-year periods have reported good retention but with a similar caries incidence to conventional sealant. Since the addition of fluoride to sealant resin does not have any detrimental effect it could certainly be used, but until the chemistry can be adapted to readily unlock the fluoride, the anti-cariogenicity cannot be attributed to the fluoride. Such cements have high levels of fluoride available for release but they suffer from the drawback of poor retention. Even with the very poor retention rates, sealing with glass ionomer does seem to infer some caries protective effect. This may be due to both the fluoride released by the glass ionomer and residual material retained in the bottom of the fissure, invisible to the naked eye. Hence, glass ionomers, used as sealants can be classed as a fissure sealant but more realistically as a fluoride depot material. They can be usefully employed to seal partially erupted molars in high risk children since eruption of the molars takes 12-18 months and during this time they are often very difficult to clean. They are also useful in children where there are difficulties with the level of co-operation, as the technique does not depend on absolute moisture control. As yet, studies of these materials used as fissure sealants while available, show no improvement over resin-based sealants and so there is nothing to recommend them in preference to resins. Retention is better for unfilled resins probably because it penetrates into the fissures more completely. If a filled resin is not adjusted there is a perceptible occlusal change, possible discomfort, and wear of the opposing antagonist tooth. It has been found that identification error for opaque resin was only 1% while for clear resin the corresponding figure was 23% with the most common error being false identification of the presence of clear resin on an untreated tooth. The disadvantage of opaque sealant is that the dentist cannot examine the fissure visually at future recalls (Figs. Safety issues There has only been one report of an allergy to the resin used for pit and fissure sealing and concern has been raised about the oestrogenicity of resin-based composites. The amount released orally is undetectable in the systemic circulation and concerns about potential oestrogenicity are probably unfounded. Sealant bulk in relation to application It is important to remember that the sealant must be kept to a minimum, consistent with the coverage of the complete fissure system including buccal and lingual pits. Sealant monitoring Once the sealant has been placed the operator must monitor it at recall appointments and repair or replenish as necessary. This leaves that surface equally at risk from caries compared to an unsealed surface. Cost-effectiveness Cost-effectiveness will depend on the caries rate for the children in the population. Where there is a higher caries rate, generalized sealing will protect more surfaces that would have become carious in the future. However, if the caries rate is very high, then the risk of developing interproximal lesions is also higher and may lead to a two surface restoration even when the fissure sealed surfaces remain caries free.

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