Questions.

One question, one page, answered from the published evidence.

• A cracked tooth or a sensitive tooth? What the pain pattern can and cannot tell you
  If one tooth has suddenly started to twinge, it may be ordinary sensitivity from exposed dentine or it may be cracked, and the pain cannot tell you which, because the commonest complaint from a cracked tooth that hurts i
• Acid reflux and tooth sensitivity: what stomach acid does to enamel
  If your teeth have started to twinge and you also get heartburn, wake with a sour taste, have just been started on a reflux medicine, or have been told by a dentist that the inside of your upper front teeth looks worn, s
• Acidic food and drink triggers: citrus, wine, fizzy drinks and why relief from cold does not last
  The toothpastes with a measured result against cold are the ones built round stannous fluoride, arginine, nano-hydroxyapatite or potassium, and in the 2026 network meta-analysis that pooled 93 randomised trials only stan
• Can a hygienist help with sensitive teeth? Cleaning, varnish and advice
  Yes: a dental hygienist or dental therapist can clean away the plaque and hardened tartar that irritate the gum line, paint fluoride varnish onto exposed surfaces, and advise on brushing and on acidic food and drink, and
• Can menopause cause sensitive teeth? What has been measured on saliva, gums and wear
  Menopause can be the background to sensitive teeth, through a drier mouth, changing gums and the wear that builds up over the same decades, but nobody has shown that it causes them. The NHS lists sensitive teeth among th
• Can you use nano-hydroxyapatite toothpaste every day? Dose, safety and routine
  Yes: morning and night, as your only toothpaste, for as long as you want to use it. The reason is not that hydroxyapatite is natural or biomimetic, but that a European scientific committee has assessed the ingredient twi
• Can you use two sensitivity toothpastes together? What combining actives does and does not add
  You can use two sensitivity toothpastes together, but no published trial has tested it, and the version most people build — a potassium nitrate paste at one brushing and a hydroxyapatite paste at the other — gives each a
• Charcoal toothpaste and sensitive teeth: what the evidence shows, and why dentists are wary
  Charcoal toothpaste gives a sensitive tooth little to gain: in the one randomised trial of charcoal products in people, a charcoal toothpaste and a charcoal powder changed tooth colour no more than an ordinary fluoride t
• Did it work, or did it just feel like it worked? Judging a sensitivity toothpaste honestly
  When sensitive teeth seem to be getting worse, the first suspect should often be the reading rather than the teeth or what you brush them with: you started when your teeth were at their most sensitive, what you feel and
• Does brushing too hard wear enamel, recede gums and cause sensitivity?
  Brushing too hard is one contributor to sensitivity on receded gums, not the proven reason they receded: two systematic reviews, published in 2007 and 2015, found the evidence linking brushing with receding gums inconclu
• Does potassium nitrate seal dentine tubules? The SEM studies disagree, and the reason is what else is in the paste
  No — and the studies that appear to say otherwise were testing whole toothpastes rather than the salt. In the companion electron-microscope arm of a four-week double-blind randomised trial in 30 adults, a 5% potassium ni
• Does potassium nitrate work within a week? Every published time point, from day three to week twelve
  Potassium nitrate is measured in weeks, and its published record is thinnest exactly where this question sits. The 2019 systematic review that sorts desensitising treatments by how soon each one reaches significance puts
• Does tooth sensitivity get worse with age? What changes in enamel, dentine and gums over decades
  In your forties and fifties, what actually helps sensitive teeth is finding out which cause is active, whether that is a gum line creeping back, enamel thinned by acid, decay starting on an exposed root or a mouth dried
• Dry mouth and sensitivity: why less saliva means less recovery
  For a dry mouth and sensitive teeth, in perimenopause or at any other age, the toothpaste to choose keeps full-strength fluoride, carries an active aimed at the twinge and leaves out the foaming detergent sodium lauryl s
• Free and low-cost NHS dental options when sensitivity needs a professional look
  The cheapest way to get a professional look at sensitive teeth in the UK is an NHS dental examination, which in England is a Band 1 charge of £27.90 as shown on nhs.uk on 10 September 2026, and which costs nothing for la
• Grinding and clenching: can bruxism cause sensitivity at the gumline?
  If your teeth have turned sensitive over a few stressful weeks and you wake with a tight jaw, grinding or clenching can be part of the reason, because the NHS counts worn-down or broken teeth, which can cause increased s
• Has Sensodyne changed its formula? How to check any toothpaste's ingredients against an older tube
  No public record will tell you whether the tube in your bathroom carries a different formula from the one you bought last year, because the rules that set out what a toothpaste sold in Great Britain must print say nothin
• Hot drinks and coffee sensitivity: why heat hurts differently from cold
  A tooth that objects to hot drinks needs the same two jobs done as one that objects to cold: the open dentine tubules narrowed, and the nerve behind them quietened, because heat and cold reach that nerve through the same
• How long does nano-hydroxyapatite toothpaste take to work on sensitivity?
  Nano-hydroxyapatite toothpaste takes about two weeks to produce a difference a trial can measure: two weeks is where the two cleanest trials, both double-blind and both with a placebo arm, took their first reading and fo
• How long to try a sensitivity toothpaste before seeing a dentist
  See a dentist now, whatever week of the tube you are on, if the pain is severe, lingers after the cold has gone, sits in one tooth, hurts when you bite, wakes you, comes with swelling or a bad taste, or is getting worse1
• Ice cream and iced drinks: why cold food is the sharpest trigger, and how to get back to it
  Two kinds of toothpaste have a claim on a tooth that hurts at a cold drink: the ones that narrow the open dentine tubule, which is nano-hydroxyapatite, calcium sodium phosphosilicate, stannous fluoride or arginine, and t
• Is tooth whitening legal in the UK? Who can do it, and why it matters for sensitive teeth
  Tooth whitening is legal in the UK when a registered dentist provides it, or a dental hygienist, dental therapist or clinical dental technician does so on a dentist's prescription, with products above 0.1% and up to 6% h
• Nano-hydroxyapatite paste versus suspension: reading the label correctly
  A hydroxyapatite percentage on a toothpaste can mean the mineral by weight in the finished paste, or the water-based paste of mineral the maker stirred in, and on most tubes it means nothing at all, because no rule oblig
• One tooth suddenly sensitive: crack, filling, decay, or recession?
  When one tooth, rather than the whole mouth, suddenly turns sensitive, the usual causes are a crack, a recent or failing filling, decay that has reached the dentine, or a patch of gum recession, and each tends to leave a
• Potassium nitrate not working: why nerve calming alone can leave the tubules open
  A potassium nitrate toothpaste that is not working usually has one of four explanations: the pain is not dentine sensitivity, the paste has not yet had the weeks it needs, your trigger is one where potassium's pooled evi
• Rinsing, mouthwash and timing: which habits change what a sensitivity toothpaste leaves behind, and which are folklore
  Rinsing, mouthwash, the amount of toothpaste and eating straight after brushing all change how much fluoride is left in your mouth, and randomised trials have measured that12. None of these habits has been shown to cance
• Sensitive teeth and diabetes: gum health, dry mouth and what to watch
  If you have diabetes and sensitive teeth, the professional oral care with the most evidence behind it is not a brand but regular care from a dentist and a dental hygienist, because diabetes and gum disease are linked in
• Sensitive teeth and eating disorders: acid erosion, gentle care and getting help
  When teeth turn sensitive in someone who is being sick often, the usual cause is stomach acid, which softens and wears away the enamel that covers the dentine underneath, most often on the inner faces of the upper front
• Sensitive teeth in winter: cold air, hot drinks and why they feel worse in the colder months
  Sensitive teeth feel worse in winter because the cold is provoking an exposed tooth more often, not because the tooth has changed with the season. What helps is the same thing that helps in July, a toothpaste that narrow
• Sensitive teeth in your twenties: whitening, energy drinks and early enamel wear
  Teeth that turn sensitive in your twenties usually have a cause you can name, and the common ones are acid from how drinks are taken, a whitening product, brushing straight after something acidic, or gums that have start
• Sensitive teeth over 60: recession, root surfaces and medication dry mouth
  Past sixty, a tooth that has turned sensitive is most often an exposed root, and what helps starts with a dental check and a sensitivity toothpaste that keeps full-strength fluoride, because the gum recession that uncove
• Sensitive teeth while breastfeeding: what changes after the birth, and what is known about each toothpaste ingredient
  While you are breastfeeding, the NHS advice for sensitive teeth is the advice for everyone: brush twice a day with a fluoride toothpaste, spit rather than rinse, and see a dentist, which is free on the NHS in England unt
• Sensitive to hot and cold at the same time: what that pattern tells you
  When both hot and cold set a tooth off, the question worth asking is not which one is worse but how long the pain lasts. Sensitivity from exposed dentine is thin and sharp, arrives with the mouthful and leaves with it; p
• Sensitivity getting worse despite a sensitive toothpaste? What to rule out first
  Sensitivity that is climbing while you brush morning and night with a desensitising toothpaste is usually being driven by something the paste was never going to reach, and the list of candidates is short enough to work t
• Sensitivity or a cavity? The differences that matter, and when to book a dentist
  Teeth feel suddenly sensitive when dentine that used to be covered is newly exposed, by a receding gum, worn enamel or a cavity, and the twinge cannot tell you which of those it is, because the NHS describes sharp pain w
• Sensitivity that lingers after the trigger has gone: what pulpal pain means
  Sensitivity that lingers after the cold or hot drink has gone is usually pulpal pain: it comes from the pulp, the soft core of nerve and blood vessels inside the tooth, rather than from exposed dentine on the surface. It
• Sensitivity toothpaste for a single tooth: why one-tooth pain usually needs a dentist
  One tooth that has suddenly become sensitive needs a dentist's look before it needs a sensitivity toothpaste, because the trials behind those toothpastes recruited teeth already diagnosed as sensitivity, and no symptom c
• Sensitivity with swelling or a bad taste: signs of infection that need treatment
  Tooth sensitivity that comes with swelling, a bad taste, a spot on the gum that weeps, or a temperature is a sign of infection, and a dental abscess needs urgent treatment from a dentist because, in the NHS's words, it w
• Sweet sensitivity: why sugar can trigger a twinge, and when it points to decay instead
  Teeth turn sensitive suddenly because a surface that used to be covered is not covered any more, and a sweet mouthful is one of the four things that can then reach the nerve through it, alongside cold, heat and acid1. Wh
• Switching sensitivity toothpaste: how long to give the new one before judging it
  Give a new sensitivity toothpaste eight weeks before you decide it has not worked, because eight weeks is where the field's own consensus guideline tells researchers to take the verdict on one1. Two weeks cannot settle i
• Teeth hurt when breathing cold air: why it happens and which toothpaste ingredients help
  Teeth hurt when you breathe cold air because moving air cools and dries an exposed patch of dentine faster than the tooth can equalise, and the fluid inside its open tubules shifts far enough for the nerve to fire. Which
• Teeth sensitive when brushing: pressure, bristles and the toothpaste that helps
  For sensitivity caused by gum recession, look for a toothpaste whose active has been tested against touch and not merely against cold, because a receded neck of dentine is what the toothbrush lands on. On the tactile pro
• Tooth pain at night: why sensitivity needs a trigger, and what wakes you instead
  Tooth sensitivity is a pain that needs a trigger, so a tooth that wakes you, or aches while nothing is touching it, is pointing to something else, such as an inflamed nerve, an infection, a crack, grinding, a sinus or a
• Tooth sensitivity when exercising outdoors: mouth breathing, cold air and dehydration
  Training outdoors leaves the tooth exactly as it found it; what a session alters is how often, and how dryly, an already bare patch of dentine is asked to react. Exercise adds three things to that patch — an open mouth,
• Toothpaste subscriptions for sensitive teeth in the UK: what is on offer and when it makes sense
  A toothpaste subscription is worth taking when the delivery interval matches how fast you actually finish a tube and the per-tube price genuinely undercuts the one-off price; it does nothing to the paste, the tooth or th
• Using it only when it hurts: what stop-start use does to a sensitivity toothpaste
  Using a sensitivity toothpaste only when it hurts does not throw the benefit away, but it does keep you in the part of the timetable where the evidence for any paste is weakest. In an industry-funded trial most of the ga
• What happens if you miss a week of a potassium nitrate toothpaste?
  Nobody has measured a week, but the week is bracketed at both ends, and neither end looks like a reset. Two manufacturer-funded double-blind randomised trials have taken people off a potassium nitrate paste on purpose —
• What happens when you stop using a potassium nitrate toothpaste: the one trial that measured it
  When you stop using a potassium nitrate toothpaste, most of the relief does not go with it. One industry-funded double-blind randomised trial has deliberately stopped a potassium paste and measured what happened, and thr
• What percentage of nano-hydroxyapatite does a toothpaste need? What the studies used
  The concentrations that have been tested in people run from 5% to 15%, and no trial has established that one figure inside that range does more than another. Six studies have compared one concentration of hydroxyapatite
• Whitening strips and sensitive teeth: what to know before you start
  Whitening strips sold in UK shops may carry no more than 0.1% hydrogen peroxide, or use a peroxide-free agent such as PAP, so they are not the strips that the published sensitivity trials tested1. Those trials used strip
• Whitening toothpastes and sensitivity: abrasivity, RDA and what to avoid
  A whitening toothpaste lifts stain off the surface of the teeth, by scrubbing or with a chemical cleaner, or tints that surface with a blue pigment, and in the UK it may contain or release no more than 0.1% hydrogen pero
• Why a toothpaste that only numbs the nerve leaves the door open
  A toothpaste built around a nerve-calming active alone does something real and measurable, and it still leaves the door open: the dentine tubule stays a channel, the cold drink still moves fluid down it, and the causes t
• Why relief that builds over weeks is a feature, not a flaw
  Relief from a sensitivity toothpaste arrives on a slope rather than at a moment, because neither of its two jobs is finished in one brushing: potassium builds up around the nerve over repeated exposures, and mineral is d