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• Hypertension

  An abnormal elevation in arterial blood pressure that can be fatal if sustained and untreated
• Hypertension is the most common primary diagnosis in the United States, accounting for 39 million office visits annually
• The prevalence of hypertension is similar among men and women but varies with race and ethnicity
• The prevalence of hypertension increases with aging, such that more than 65% of Americans aged 60 years and older have hypertension
• Primary (essential) hypertension


  About 90% of patients have no readily identifiable cause for their disease
• Secondary hypertension


  In the remaining 10% of patients, an underlying cause or condition may be identified
• Identifiable causes of hypertension

  • Chronic kidney disease (e.g., diabetic nephropathy)
  • Chronic steroid therapy and Cushing syndrome
  • Coarctation of the aorta
  • Drug induced or drug related
  • Pheochromocytoma
  • Primary hyperaldosteronism
  • Renovascular disease
  • Sleep apnea
  • Thyroid or parathyroid disease

  
• Diagnosis of hypertension


  1. Thorough medical history

  2. Complete physical examination

  3. Routine laboratory tests

  4. Classification and diagnosis of BP based on average of two or more properly measured BP readings obtained in the seated patient on each of two or more office visits

  5. Measurement of BP using auscultatory method with manual aneroid or hybrid sphygmomanometer or electronic automated devices
• Basic testing for hypertension

  • Fasting blood glucose
  • Complete blood count
  • Lipid profile
  • Serum creatinine with eGFR
  • Serum sodium, potassium, calcium
  • Thyroid stimulating hormone
  • Urinalysis
  • Electrocardiogram

  
• Optional testing for hypertension

  • Echocardiogram
  • Uric acid
  • Urinary albumin to creatinine ratio

  
• Early signs and symptoms of hypertension

  • Elevated blood pressure readings
  • Narrowing and sclerosis of retinal arterioles
  • Headache
  • Dizziness
  • Tinnitus

  
• Advanced signs and symptoms of hypertension

  • Rupture and hemorrhage of retinal arterioles
  • Papilledema
  • Left ventricular hypertrophy
  • Proteinuria
  • Congestive heart failure
  • Angina pectoris
  • Renal failure
  • Dementia
  • Encephalopathy
• Lifestyle modifications for prevention and reduction of high blood pressure

  • Weight loss
  • DASH (Dietary Approaches to Stop Hypertension) diet: fruits, vegetables, low-fat dairy products, reduced intake of cholesterol-rich foods, reduced intake of saturated and total fats, reduced sodium intake
  • Regular aerobic physical activity on most days (30 minutes of brisk walking)
  • Quit smoking
  • Limited alcohol intake
• Pharmacologic therapy for hypertension

  • Diuretics: Low-dose thiazide diuretics, Hydrochlorothiazide, Chlorthalidone
  • Blockers of the Renin-Angiotensin System: ACE inhibitors, Captopril, Lisinopril, Ramipril; Angiotensin II receptor blockers, Losartan, Valsartan, Candesartan
  • Aldosterone Antagonists: Spironolactone
  • Beta Blockers
  • α Adrenergic Blockers: Prazosin, Doxazosin, Terazosin
  • Calcium Channel Blockers: Nifedipine, Verapamil, Diltiazem
  • Direct Vasodilators: Hydralazine, Minoxidil
• White coat hypertension


  About 20% of patients with untreated stage 1 hypertension have consistently elevated BP only in the presence of a health care worker but not elsewhere

  
• Orthostatic hypotension


  Hypertensive patients are more susceptible to an excessive fall in blood pressure when brought from a supine to an upright position, resulting in faintness, light-headedness, dizziness, confusion, or blurred vision

  
• Hypertensive emergency


  The association of substantially elevated BP with acute hypertension-mediated organ damage (HMOD)
• Dental implants have given the profession and the patient an extremely predictable and effective means of tooth replacement

  
• The partially edentulous patient can now undergo replacement of a single tooth or several missing teeth with implant retained crowns and enjoy the function and esthetics they had with their natural teeth

  
• The completely edentulous patient no longer has to live with compromised function and the reduced confidence that traditional full denture wearers have historically experienced
• Dental implants can offer the edentulous patient comfort, function, and confidence with either fixed prosthetics or implant-retained removable prosthetic options

  
• Per-Ingvar Brånemark, a Swedish professor of anatomy, had a serendipitous finding while studying blood circulation in bone that became a historical breakthrough in medicine

  1950s
• Osseointegration


  The direct structural and functional connection between organized, living bone and the surface of a load-bearing implant without intervening soft tissue between the implant and bone

  
• Previous implant designs


  • Blade vents
  • Press-fit cylindrical
  • Subperiosteal
  • Transmandibular
• Some of these implant systems were initially stable and appeared to be successful over short-term periods (e.g., 5 years) but failed to remain stable; they became symptomatic or loose and failed over longer periods
• Lacking predictability, these implant systems are no longer used
• Since the time of the Brånemark studies, millions of patients have been treated worldwide using variations of these techniques with implants of different geometries and surface characteristics
• The serendipitous finding of Brånemark was that when a hole is prepared into bone without overheating or otherwise traumatizing the tissues, an inserted biocompatible implantable device would predictably achieve an intimate bone apposition, as long as micro movements at the interface were prevented during the early healing period

  
• Current most common implant designs

  • Screw-shaped or threaded cylindrical implant
  • Parallel or tapered longitudinal shape
• Threaded implant design


  It engages bone well and is able to achieve good primary stabilization

  
• Tapered implant design


  • It requires less space in the apical region (i.e., better for placement between roots or in narrow anatomic areas with labial concavities)
  • Advocated for use in extraction sockets
• Implant surface characteristics (microtopography) have been shown to positively influence the healing process

  
• Modifications in implant surface

  • Surface energy
  • Chemical composition
  • Surface topography

  
• Additive processes


  Modify the microstructure/macrostructure and chemical nature of the implant surface by adding materials or chemicals to the existing surface
• Additive processes


  • Inorganic mineral coatings
  • Plasma spraying
  • Biocoating with growth factors
  • Fluoride and particulates or cements containing calcium phosphates, sulfates, or carbonates
• Subtractive processes


  Modify the microstructure and chemical nature of the implant surface by removing or altering the existing surface

  
• Implant surfaces that are modified at the microscopic level with techniques such as acid etching are thought to promote favorable cellular responses and increased bone formation in close proximity to the surface

  
• In general, additive surface modifications tend to increase the surface texture greater than subtractive surface modifications, resulting in topographically "rougher" implant
• Titanium is a reactive metal that oxidizes within nanoseconds when exposed to air. Because of this passive oxide layer, the titanium then becomes resistant to corrosion in its CP form
• Some alloys, such as titanium-aluminum 6%, vanadium 4% (Ti 6Al 4V), are known to provoke bone resorption as the result of leakage of some toxic components