Many patients presenting for implant treatment will have one or more chronic medical conditions requiring one or more forms of medication. These concepts, known as multimorbidity and polypharmacy respectively, are discussed in the ITI Academy Learning Module 'Introduction to Pharmacology.' It is recommended that the module 'Introduction to Pharmacology' is viewed as a prerequisite for completion of this module. During implant treatment, especially during the surgical phase, clinicians prescribe and administer pharmacologically active substances to assist in patient management. It is therefore important to recognize potential interactions that may occur between a patient's regular medications and those given during implant treatment. Additionally, the drugs that patients take and the conditions for which these drugs are required can influence the progress and outcome of implant treatment. It is essential to understand the potential risks so that patients can be treated safely, so that they understand what may happen during treatment, and so that they are aware of how to manage their own postoperative period. Failure to take these matters into consideration can result in harm to the patient, treatment complications, treatment failure, and, in some circumstances, legal action against the treating practitioner.

Effective pain control is mandatory in the provision of operative dental treatment and is commonly achieved with adequate local anesthesia. Local anesthetic drugs work by blocking sodium channels in cell membranes, preventing the influx of sodium ions into axons and therefore halting the transmission of action potentials along nerve axons. This can also have an effect on cardiac muscle, so patients with cardiac conduction problems (or 'heart block') should be treated with caution. Local anesthetic solutions often also contain vasoconstrictors such as adrenaline or epinephrine to limit the dissipation of the local anesthetic solution away from the injection site, thereby prolonging the anesthetic effect, and to provide some assistance with hemostasis. Care should be taken to avoid intravenous injection of local anesthetic solution to avoid systemic spread of the anesthetic and vasoconstrictor, both of which can have cardiac effects. Most patients with stable heart conditions can be safely treated in the dental surgery using effective pain control; the stress of a painful procedure will result in the release of endogenous catecholamines, which may also cause cardiac events, the risk of which is greater early in the morning.

As noted, local anesthetics should be used with care in patients with cardiac disease or heart block. Additionally, when using local anesthetics in the elderly or other patients with reduced liver function, practitioners should limit the dosage given. When considering maximum safe dosages and an appropriate safety margin, the dentist must consider how long the procedure may take, particularly with regard to the resilience of the patient, their medical status, and age.

The duration of action of a local anesthetic is related to its pharmacokinetics and how it is metabolized. Lidocaine is metabolized in the liver; its metabolites are toxic and are themselves anesthetic agents requiring second-pass metabolism. Articaine, on the other hand, is mostly metabolized in the bloodstream by carboxyesterase and partly in the liver by microsomal enzymes with no toxic metabolites and is therefore excreted more rapidly.

Local anesthetic agents can interact with other medications, and the rate of adverse drug events or ADEs is increased when multiple other medications are taken. The potential interactions between local anesthetics and beta blockers were discussed in the ITI Academy Learning Module 'Introduction to Pharmacology.' Many other antihypertensive medications may interact with local anesthetics, but the risk of an adverse event is low, provided that the dose of local anesthetic is limited to only one or two cartridges in relevant patients. This of course may affect the planned operating time, and appropriate assessment of cardiac history is therefore mandatory. Patients taking digoxin should have pulse and blood pressure recorded prior to administration of vasoconstrictor-containing local anesthetics and be carefully monitored as there is a risk of arrhythmias. Patients taking long-acting nitrate medications such as nitroglycerin or glyceryl trinitrate or vasodilator medications such as doxazosin may show decreased effectiveness of the vasoconstrictor and therefore shorter anesthetic duration. One of the few absolute indications for the use of local anesthetic without vasoconstrictor is in patients with Parkinson's disease, in whom there is a serious risk of interaction with certain anti-Parkinson's medications resulting in hypertensive events.

Implant surgery often involves the use of medications to control anxiety - in many countries, effective pain and anxiety control are considered to be a right of the patient and a duty of the clinician. Commonly used sedative and anxiolytic medications belong to the benzodiazepine family of drugs that induce drowsiness and reduce anxiety. Unfortunately, these drugs may result in a degree of respiratory depression and, at excessive doses, suppression of protective reflexes. Care must be exercised to titrate the dose to ensure that desired effects are achieved while unwanted side effects are minimized. Oral administration of sedatives, whilst straightforward, is less effective, with a lower level of anxiolysis, a slower duration of onset, less ability for dose titration, and limited effectiveness in terms of both intraoperative sedative effect and postoperative amnesia.

Conscious sedation is defined as 'a technique in which the use of a drug or drugs produces a state of depression of the central nervous system (or CNS) enabling treatment to be carried out, but during which verbal contact with the patient is maintained throughout the period of sedation. The drugs and techniques used to provide conscious sedation for dental treatment should carry a margin of safety wide enough to render loss of consciousness unlikely.' A dentist's ability to administer IV conscious sedation is dependent on local laws and regulations; when permitted, specific additional training is required. In many countries only anesthesiologists can provide this level of sedation. In any case, a prudent approach is to engage the services of an anesthesiologist to sedate and monitor the patient while the dentist focuses on providing oral care. Intravenous or IV conscious sedation may be provided with benzodiazepines or with other drugs such as propofol. Typically a single drug is used; there are increased risks when multiple sedative agents are used. Because the risk of a medical emergency is increased, IV sedation should only be provided in an appropriate environment with trained personnel, adequate recovery facilities, and suitable equipment. It is important that the sedative dose is carefully titrated to minimize unwanted side effects. At the correct dose, verbal contact can be maintained, and the protective reflexes of gagging and swallowing are preserved. This technique provides excellent intraoperative sedation with good postoperative amnesia; the typical dose produces 45 minutes of useful sedation. However, these drugs do not provide any degree of pain control.

The effects of sedative and anxiolytic agents may be extended beyond the time taken for treatment, so patients must be advised that they should make arrangements for transportation home after their appointment; they cannot drive a car. Because oral sedatives may be given up to an hour before the procedure, this may also apply to travelling to the appointment. Patients should also have a responsible adult caregiver monitor them during their recovery. It is important to note that some of these medications can be habit forming, so clinicians should avoid prescribing a greater quantity of drug than is needed for the procedure. As a class of drugs, the benzodiazepines do have some potential to interact with other drugs. Concomitant administration of these medications with other central nervous system depressants should be avoided, and patients should be counseled not to drink alcohol on the day of their surgery. Two classes of drugs pose a serious risk for an adverse drug event when taken together with midazolam: macrolide antibiotics such as erythromycin and azole antifungals such as fluconazole.

Antimicrobial stewardship is becoming an important aspect of healthcare, as indiscriminate use of antibiotics has been shown to lead to increased bacterial resistance. As part of best practice, antimicrobial medications should only be used in cases where there is an active bacterial infection, (as evidenced by fever, lymphadenopathy, and/or suppuration) or where prophylactic treatment is proven to be both effective and necessary. Implant treatments carried out using an appropriate aseptic technique rarely result in infections. As such, the routine use of antibiotic prophylaxis for surgical implant procedures is contraindicated. When using antimicrobials, follow the MIND-ME Creed. The letters in this acronym stand for guiding principles of the creed. Click on each letter to learn these principles. When done, click the 'Next' button at the bottom right to proceed to the next slide. M - Microbiology guides therapy. Use agents with an appropriate spectrum of action to get the best effect. Microbiological testing of the infective bacterium against available antimicrobials will provide a targeted response. I - Indications are evidence based. Only use antimicrobials where there is good evidence of effectiveness and need. N - Narrowest spectrum required. Avoid using broad-spectrum drugs where they are not needed. D - Dosage appropriate to the infection and to the site. Use the dose that is needed to achieve control of the infection. Under-dosing increases the risk of developing resistant strains. M - Minimal duration. Use the antimicrobial regime for as long as is needed to be effective, but avoid longer use as this too increases the risk of developing resistance. E - Ensure monotherapy where possible. Like broad-spectrum drugs, the use of multiple antimicrobial drugs should be avoided unless they are needed. The use of multi-agent protocols increases the potential for undesirable side effects and the development of bacterial resistance.

A number of antibacterial drugs may be used to manage infections that may arise during implant treatment. These include the beta-lactams such as penicillins and amoxicillin. Some beta-lactams may be combined with clavulanic acid, which inhibits the bacterial enzyme beta-lactamase and thereby broadens their spectrum of action. Other antimicrobials are the cephalosporins, lincosamides, macrolides, and nitroimidazoles. Of these, the most commonly used drug is metronidazole. As should always be the case, targeted therapy should be used, in which the agent is of proven effectiveness against the bacteria involved in the infection. Antibiotic sensitivity tests, such as the one depicted here, allow selection of the most effective drug.

Generally, the term 'antibiotic sensitivity' refers to the bacterial species against which the antibiotic will be effective. However, this term is sometimes used to describe a so-called allergy to an antibiotic, when in fact the term 'intolerance' should be used. Allergy and intolerance are different; however, antimicrobials should be used with caution when there is a history of either condition. True allergy is immunologically mediated by immunoglobulin E (or IgE). It is rapid in onset, reproducible, and can lead to anaphylaxis. Delayed immune reactions can occur after a few days of antibiotic therapy and are T-lymphocyte mediated. Examples are the rashes seen when antibiotics are administered during Epstein-Barr or HIV virus infections. There is no recurrence when the patient is well. Some delayed immune reactions can be serious, such as Stevens-Johnson syndrome. Intolerance is a sensitivity reaction that is not immunologically mediated but instead dependent on the combined action of the medication and patient factors, resulting in an unusually low threshold for developing known adverse effects of the antibiotic - such as diarrhea caused by antibiotic colitis. The decision to prescribe in such a situation is dependent upon a risk/benefit analysis.

Some antibiotic interactions are very important. Certain macrolides (such as erythromycin) may potentiate the effect of warfarin as well as other new anticoagulants such as apixaban and dabigatran. The same interaction can be seen with azole antifungals. There is a risk of serious cardiomyopathy when macrolides are used with statins. The table by no means details all relevant interactions. The importance of an accurate and contemporary medical history is clear.

Most dental pain is inflammatory in origin, resulting from tissue damage. Postoperative pain following implant surgical procedures is a consequence of such tissue damage and therefore can be well managed using anti-inflammatory drugs. The most commonly used anti-inflammatories in dentistry are the nonsteroidal type, referred to as NSAIDs. These drugs act by inhibiting the synthesis of inflammatory mediators such as the prostaglandins. The effectiveness of these medications is dose dependent, with increasing doses needed to adequately manage severe pain. Unfortunately, the potential for side effects is also related to dose, and high doses may become contraindicated if the risk of side effects is too great. In such cases paracetamol or acetaminophen can be a useful alternative, or may be taken in conjunction with a nonsteroidal anti-inflammatory to enable the latter to be used at a lower dose. There is some evidence to suggest that the preemptive administration of analgesic drugs just prior to surgery may attenuate the nociceptive response and thereby result in more effective postoperative pain control.

Caution should be used when prescribing nonsteroidal anti-inflammatories in patients with a history of asthma. Anti-inflammatory medications have been reported to induce or exacerbate asthma attacks in sensitive individuals. Caution is also recommended in patients with a history of gastric ulceration, who may have bleeding issues following use of these drugs. Nonsteroidal anti-inflammatories have also been noted to increase the risk of heart attacks and strokes. Care should be taken in using these medications in patients with other risk factors for these conditions. Some medications when taken together with NSAIDs can increase the risk of side effects. NSAIDs have anticoagulant effects, so concomitant use with other anticoagulants such as warfarin should be avoided. NSAIDs interact with angiotensin converting enzyme inhibitors (commonly known as ACE inhibitors) and angiotensin II receptor blockers, resulting in increased risk of renal damage and renal insufficiency. They can also reduce the renal response to diuretics.

In dentistry the most commonly used opioid analgesics are the family of medications that contain codeine, often mixed with either a nonsteroidal anti-inflammatory or paracetamol. When taken, the codeine in these medications is metabolized into morphine, which is the active drug. Opioids act by blocking nociceptors in the central nervous system and by dampening the patient's emotional response to the pain. Care should be taken when prescribing long courses of codeine-containing analgesics as these, like other opioids, can be habit forming. Codeine and other opioids can interact with a number of other central nervous system depressant drugs like sedatives, antidepressants, anesthetics, and alcohol, leading to respiratory depression. Use of these medications in patients who are also taking anticholinergic drugs can lead to potentiation of these medications, resulting in constipation and urinary retention problems. Additionally, drugs that inhibit hepatic function can result in enhanced opioid effectiveness and potential toxic effects. Unfortunately, many medications can have an impact on liver function, even common medications such as alcohol and the proton pump inhibitors used to manage reflux disease. Care should therefore be exercised in titrating the dose of any opioid used for postoperative pain relief.

Medications Used in Implant Treatment, Key Learning Points: The maximum dose of local anesthetic should be halved in patients aged 65 and older and in those with reduced liver function. Use of sedatives in patients taking other central nervous system depressants, macrolide antibiotics, and azole antifungals should be avoided. Antibiotics should be used only when clinically indicated; they are not a substitute for aseptic implant surgery technique. Nonsteriodal anti-inflammatories are the drugs of choice for postoperative pain but should be used with caution in patients with asthma, gastric ulcers, or hypertension. A complete, recent medication list should be assessed prior to any treatment.

Antiresorptive medications are used in the treatment of osteoporosis and malignancies affecting bone. They are used to address an imbalance between bone deposition and bone resorption. However, their use can result in problems with bone and soft tissue healing in the oral cavity, where areas of damaged bone are not resorbed and soft tissue breaks down over the necrotic bone. This condition was once known as bisphosphonate-induced osteonecrosis of the jaw (or BRONJ), but the term has now been changed to medication-related osteonecrosis of the jaw (or MRONJ) to reflect the different types of medication now used. What are some of the medications commonly used today? Let's take a look at three types of antiresorptive agents and their typical dosing regimens: the bisphosphonates, monoclonal antibodies, and other antiangiogenic drugs. Antiangiogenic drugs are used in the treatment of metastatic bone cancers and are not used in the treatment of osteoporosis. Click on any group to explore these medications. When done, click the 'Next' button at the bottom right to proceed to the next slide. Bisphosphonates can be divided into non-nitrogen-containing compounds such as etidronate and nitrogen-containing compounds such as alendronate, risedronate, ibandronate, pamidronate, and zoledronate, with the nitrogen-containing compounds being more potent as these drugs bind to bone. Some bisphosphonates are given orally, usually once a week, and others as a yearly intravenous infusion. Monoclonal antibodies include RANKL inhibitors such as denosumab, which is administered as a twice-a-year injection. VEGF-A inhibitors such as bevacizumab are also included in this category. Bevacizumab is administered as an infusion every 2 weeks. Other commonly used antiangiogenics include the tyrosine kinase inhibitor sunitinib, which is given orally once a day.

It is now generally accepted that the risk of MRONJ in patients on oral bisphosphonate therapy is low. Because nitrogen-containing bisphosphonates bind to bone, they are consequently concentrated over time in regions of high bone turnover such as the jaws, producing a time-dependent effect where the risk may increase after taking the drug for more than 4 years. The risk is higher with intravenous bisphosphonates and denosumab, and in patients taking additional medications that may also affect healing, such as steroids and chemotherapeutic agents. The risk of MRONJ in patients taking antiresorptive medications as part of cancer treatment is in the order of 100 times higher.

The management of patients on parenterally administered antiresorptive medications should always be discussed with their rheumatologist or oncologist as appropriate. As RANKL inhibitors (like denosumab) do not bind to bone, their effect is largely diminished after approximately 6 months. If oral surgery procedures are necessary and beneficial, it may be possible to consider operating at the end of a dosing cycle, for example, shortly before the next infusion or injection. As stated in the ITI Academy Learning Module 'General Risk Factors and Contraindications for Implant Therapy' patients currently being treated with high-dose antiresorptive agents for cancer-related conditions are not candidates for implant therapy in general practice and should be referred to specialized comprehensive centers.

Immunomodulatory therapy is used to suppress the immune response or to block cytokine action in the treatment of autoimmune and connective tissue disorders such as multiple sclerosis and rheumatoid arthritis. These medications are also used in organ transplantation and in targeted drug therapy in the treatment of certain cancers. Drugs typically used for immunomodulatory therapy fall into three categories: the glucocorticoids, the systemic nonbiological immunomodulators or SNBIs, and the biological response modifiers or BRMs. Click on each drug family to learn some of its therapeutic uses. When done, click the 'Next' button at the bottom right to proceed to the next slide. Glucocorticoids such as hydrocortisone and dexamethasone are employed for their anti-inflammatory properties. Systemic nonbiological immunomodulators such as azathioprine and cyclosporin are prescribed for conditions such as rheumatoid arthritis, ankylosing spondylitis, psoriasis, Crohn's disease, and ulcerative colitis. Biological response modifiers may also be prescribed for these same connective tissue disorders as well as malignancies such as non-Hodgkin's lymphoma. These drugs are also used "off label" - that is, for conditions other than those for which they have been officially approved. In dentistry, off-label uses of biological response modifiers include oral disorders such as recurrent aphthous stomatitis and Behçet disease, lichen planus, pemphigus, mucous membrane pemphigoid, orofacial granulomatosis, and Sjögren's syndrome. Three commonly used biological response modifiers are infliximab, rituximab, and tocilizumab.

There are no human studies of any effect on osseointegration, but patients on immunomodulators may have compromised general health with other considerations and may be better assessed in a specialist environment. Drug interactions and adverse effects are very common, and specialist advice should be sought before prescribing to patients taking complex medications. Any immunosuppressant therapy will predispose the patient to infections and paradoxically to malignant disease. Agranulocytosis increases predisposition to infection, often caused by commensal microorganisms. The spread of infection may be rapid and atypical. Candidiasis is common. As with chemotherapy, thrombocytopenia - a deficiency of platelets - may occur, causing prolonged bleeding. Finally, wound healing may be impaired due to agranulocytosis. The considerations with patients on immunomodulators are similar to those for patients with immune deficiencies.

Oral side effects are common and include altered taste sensation (or dysguesia), ulceration, and lichenoid reactions. Profound immunosuppression may lead to hairy leukoplakia, lymphomas, oral keratosis, or Kaposi's sarcoma. There is no clear evidence regarding these drugs and osseointegration. Evidence does not clearly show that glucocorticoid therapy affects implant integration or long-term survival, even though prolonged treatment with glucocorticoids can deleteriously affect skeletal bone mass, causing osteoporosis. There is a similar lack of evidence relating to osseointegration and cyclosporine, a systemic nonbiological immunomodifier. Animal studies have indicated a negative effect on bone healing around implants with cyclosporin and, unsurprisingly, a possible negative effect on previously well-integrated implants. Biological response modifiers are new, and it is not yet known whether such medications affect implant integration or their long-term survival. Although there are no reports on implant placement in patients taking these drugs, inevitably there will be an increased risk of infection, which in the presence of other chronic conditions such as diabetes could be severe.

Diabetes mellitus arises in two distinct forms. Type 1 results from destruction of insulin-forming cells in the pancreas. Patients affected with this condition require insulin replacement therapy, often involving multiple injections every day. Type 2 diabetes results from an increasing resistance of cell receptors to the patient's own insulin. This can be controlled by diet, but in cases where this is unsuccessful medications are also used. Type 2 diabetes patients may also find that they develop an insulin deficiency in which their pancreas produces less insulin over time, resulting in a need for supplemental insulin. Insulin injections and/or a number of different orally administered medications are used to manage this disease and may indicate which form of diabetes is present. Each of these will have some potential for interaction with other drugs, so it is prudent to discuss prescription of additional medications with the patient's medical specialist. Side effects can also be variable but may include gastrointestinal upsets, rash, weight gain, and renal problems leading to fluid retention. The main concern in implant therapy with diabetic patients is not so much the drugs that are used to manage it, although there are some important interactions, but rather the effect that the condition can have on the outcome of implant treatment. Poorly controlled diabetes is associated with impaired healing and increased risk of infection. Whilst the mechanism of these processes is still unclear, care should be taken to ensure that diabetic patients have stable and well-controlled blood glucose levels. Patients should also be advised to maintain their normal meal and medication regime on the day of implant surgery, and the timing of the procedure should be planned appropriately. Postoperative nutrition should also be planned, as there may be difficulty in eating as a result of the surgical procedure.

Tobacco smoking is a widespread habit and has been associated with a multitude of chronic health issues. There is a known link between smoking and increased incidence of periodontal disease, and the same link appears to apply to peri-implant disease. In surgical treatments such as implant placement, smoking is associated with compromised wound healing and increased risk of infection and scarring. These effects are believed to be related to nicotine and other tobacco-derived chemicals affecting both the patient's immune response and the fibroblasts that play a critical role in angioneogenesis. Nicotine is a vasoconstrictor, reducing blood flow to healing tissues and also reducing oxygenation as carbon monoxide preferentially binds to hemoglobin compared to oxygen, producing carboxyhemoglobin. Ideally, to reduce risk to implant surgery, smoking cessation is desirable prior to implant therapy. There is no proven value to short-term reduction in smoking habit.

Medications and Conditions That Can Influence Wound Healing, Key Learning Points: The risk of medication-related osteonecrosis of the jaw in patients on oral bisphosphonates is low; the risk is higher in patients on injected or IV antiresorptive drugs. Patients being treated with high-dose antiresorptive agents are not candidates for implant therapy. Patients with autoimmune diseases or who are immunocompromised are predisposed to infections, impaired wound healing, and prolonged bleeding. The medications used to treat these conditions have oral side effects such as ulceration and altered taste. Diabetes itself, rather than the medications used to control it, is associated with impaired healing and increased risk of infection. Smoking is associated with compromised wound healing and increased risk of infection.

Patients who present for implant therapy may be taking anticlotting agents, or so-called blood thinners. Congenital coagulation defects are generally detected in childhood. Acquired defects may arise from liver disease or as side effect of medications prescribed for chronic conditions such as thromboembolic diseases, myocardial infarction, or heart valve disorders. There are two classes of anticlotting agents, the antiplatelet drugs and the anticoagulants. How do these agents prevent or reduce clotting, and what are the most commonly prescribed drugs? Click on each drug class to learn more. When done, click the 'Next' button at the bottom right to proceed to the next slide. Antiplatelet drugs inhibit platelet agglomeration, adhesion, activation, or a combination of these processes. Acetylsalicylic acid (or aspirin), monoclonal antibodies, phosphodiesterase inhibitors and thienopyridines such as clopidogrel all fall into this category. It is important to note that many other drugs can have a degree of antiplatelet activity, including alcohol, antibiotics, cytotoxic agents, psychoactive drugs, diuretics, and medications used in the treatment of cardiovascular disease. Anticoagulants interfere with various clotting factors. Heparins have an immediate and short-lived effect. Warfarin is a coumarin drug with a half-life of approximately 40 hours. Warfarin has many important interactions with other medications and dietary components and supplements. The novel oral anticoagulants now used in place of warfarin have shorter half lives of 12 to 14 hours and include direct thrombin inhibitors such as dabigatran and factor 10a inhibitors such as rivaroxaban and apixaban.

All of these drugs are prescribed for important reasons that may be life threatening if not controlled. If the use of anticlotting agents is not stopped prior to a surgical procedure, there is a risk of intra- and postoperative bleeding. However, cessation of therapy is often not warranted or necessary, as such bleeding can be managed with local measures by a trained surgeon. Stopping these drugs raises the risk for a thromboembolic event such as deep vein thrombosis, pulmonary embolism, or stroke. Clinicians must weight the risk of stopping vs. the risk of continuing; if it is felt that any drug should be stopped, then there are two considerations: first, consultation with the patient's medical team to seek advice on likely risks and appropriate management; second, consideration of treating the patient in a specialist unit rather than in general practice.

For a simple surgical procedure such as placement of a single implant or extraction of up to three teeth, the management recommendations are as follows: It is rarely necessary to consider stopping aspirin. The average life cycle of a circulating platelet is 8 or 9 days, and therefore any cessation of antiplatelet therapy would have to be at least this long to be effective. It should be noted that antiplatelet drugs do not interfere with blood coagulation, and so local measures such as compression can be used to control hemorrhage. Likewise, clopidogrel rarely must be stopped unless taken in combination with aspirin; however, if clopidogrel has to be stopped for more complex surgery such as sinus floor elevation, then cessation should take place 7 days preoperatively. If the patient has a recent clotting time result - known as an INR, or International Normalized Ratio - that is 3.5 or less, then cessation of warfarin is not indicated. However, one should be mindful that the effectiveness of warfarin changes if the patient has a systemic infection or is taking any medications that interact with warfarin such as antibiotics and antifungals. It is also important to consider the additive effect of certain analgesics, including paracetamol and nonsteroidal anti-inflammatory drugs. Many herbal remedies may also affect warfarin such as St. John's wort, echinacea, Gingko biloba, ginseng, and even garlic. The direct oral anticoagulants are gradually replacing warfarin therapy. They do not require direct management, and INR measurement is ineffective. In the absence of clinical studies the effect is estimated as being similar to an INR of 4. They are less affected by diet than warfarin, but anise, bilberry, alfalfa, and grapefruit can cause important effects. The short half-life permits safer and more effective short-term cessation where required, after consultation with the patient's medical team. In any case, the timing of treatment should be such that any postoperative bleeding can be managed during normal working hours, so appointments should be scheduled earlier in the day and on a weekday, when full facilities are readily available for the management of hemorrhage. All surgeons involved in the placement of dental implants should be able to recognize the different types of hemorrhage and know how to control bleeding in the most appropriate manner.

Selective Serotonin Reuptake Inhibitors are a class of medications primarily used to treat depression and various anxiety disorders. SSRIs work by increasing the levels of serotonin, a neurotransmitter that contributes to feelings of well-being and happiness, in the brain. They do this by blocking the reuptake (or reabsorption) of serotonin into neurons, making more serotonin available in the synaptic space between nerve cells. Systematic reviews and meta-analyses have confirmed that the use of SSRIs is closely linked to an increased risk of implant failure. Healthcare providers should recognize this connection and inform patients about the potential risks associated with implant therapy during the informed consent process.

A wide range of recreational drugs are in use in the community, and dental implant patients may be users. These drugs range from socially acceptable drugs (such as alcohol) to illegal substances like cocaine, opiates, and methamphetamines. The potential for many of these substances to affect implant therapy is mostly unclear, as there is a paucity of evidence on their effects on osseointegration and wound healing. There is some animal evidence to indicate an association between cannabis smoking and implant failure, but more human research is required. However, use of any of these compounds can lead to effects in patients that may compromise their willingness or ability to comply with homecare instructions, and this may impact on implant risk. As such, implant therapy might best be avoided in individuals with significant, and obvious, substance abuse problems. There is also the risk of serious adverse drug events in some circumstances when the use of such substances is not known to the clinician.

Cigarette smoking has been identified as impacting on the risks of implant failure and on the risk of developing peri-implant disease. These risks are significantly higher in smokers than in nonsmokers. The ITI's Fourth Consensus Conference considered this issue and concluded that: "Smoking is not a contraindication for implant placement. However, patients should be informed that the survival and success rates are lower in smokers. Heavy smokers should be informed that they are at greater risk of implant failure and loss of marginal bone. Patients who smoke should be informed that there is an increased risk of implant failure when sinus augmentation procedures are used."

Medications That Can Complicate Implant Treatment, Key Learning Points: It is recommended to consult the patient's medical team before instructing the patient to cease their anticlotting therapy. Cessation of anticlotting therapy is often not required for routine surgical procedures. Recreational drugs are a risk factor for implant therapy because they may affect patient compliance. Smoking affects the survival and success rates of dental implants.

Pharmacology with Relevance to Dental Implant Therapy, Module Summary: All medications used in implant therapy have the potential to cause adverse drug events. The risk of adverse drug events is both dose-dependent and affected by patient factors such as age and comorbidities. Treatment should not be initiated without a complete and recent medical history and medication list. Some chronic conditions are known to present a relative risk for complications, such as diabetes and autoimmune diseases. In other cases it is the medications employed in disease management that are factors in poor healing.

Risk of adverse events related to local anesthetics can be minimized by limiting the maximum dose and using solutions without vasoconstrictor when indicated by the patient's medical history. Follow the MIND-ME creed for appropriate use of antimicrobials that avoids contributing to antibiotic resistance. Nonsteroidal anti-inflammatories are the first-line pharmacologic agents for the treatment of dental postoperative pain, but their use may be contraindicated in patients with cardiovascular or renal disease. Patients on high-dose antiresorptive drugs are generally not candidates for implant therapy. It is usually not necessary to discontinue anticlotting therapy for simple oral surgeries.