--- type: Article title: "Do Clear Aligners Hurt? Pressure, Sore Spots and the First Days with Aligners" description: "Do clear aligners hurt? How long pressure lasts after changing trays, what helps with sore spots and lisping, and when to contact us." resource: https://www.just-kfo.de/en/articles/does-clear-aligner-hurt-pressure-first-days/ language: en tags: [orthodontics, articles] timestamp: 2026-11-07T06:06:55+01:00 --- # Do Clear Aligners Hurt? Pressure, Sore Spots and the First Days with Aligners Blog Do Clear Aligners Hurt? Pressure, Sore Spots and the First Days with Aligners Clear aligners can hurt at first, usually as a feeling of pressure or tension after insertion and after each aligner change. It is most noticeable on the first day (Gao et al., 2021). In a survey of 94 adults, it lasted one to three days for just over two-thirds. Almost everyone who reported pain described it as mild or moderate (Caldas et al., 2024). Perhaps you have just received your first aligner, or you want to know what to expect before starting treatment. Here you will find answers from studies and from our orthodontic practice: why aligners press, how long it lasts, what helps with pressure points and lisping, and when you should contact us. Why do clear aligners press? Each aligner in a clear aligner system is shaped slightly differently from the previous one and moves the teeth forward by a small, pre-planned step. The pressure reaches the periodontal ligament, i.e. the fibers that hold the tooth in the jawbone. Remodeling begins there, and you feel that as tension. How gently the force is applied can be influenced during the planning stage. In our published cases, two aligners were created for each treatment step, first a thinner one, then a firmer one, made from foil approximately 0.5 and 0.75 millimeters thick (among others Schupp et al., 2020). This way, a gentler force acts on the teeth first, then a stronger one, as in the treatment example: Crowding corrected with aligners. Good to know: Little pressure does not mean the aligner is not working. How long does a new aligner press? At the start of treatment, in a comparative study with 110 adults, the pain was strongest on the first day and then decreased day by day (Gao et al., 2021). In another study with 64 patients, the pain with aligners, as with fixed braces, was strongest about 24 hours after insertion and lowest on the seventh day (Almasoud, 2018). How long it lasts for you cannot be said in general terms. With each new aligner, i.e. every one to two weeks, the process starts over. Over the course of treatment, it usually becomes easier. In a randomized study, the feeling of pressure after appointments one and two months later was consistently lower than at the start of treatment (White et al., 2017). Do clear aligners hurt less than fixed braces? On average, yes, especially at the beginning. A review of 32 studies found less pain with aligners in the early treatment phase than with fixed braces (Kaur et al., 2026). An older review came to the same conclusion for the first few days; after that, the values became similar (Cardoso et al., 2020). Clear aligners Fixed braces Pressure in the first few days lower on average higher on average Pressure after a few weeks similar to lower, studies are inconsistent similar to higher Friction in the mouth aligner edges, attachments brackets, wire ends Which appliance fits your situation is determined by the examination, not by the pain. For more on fixed braces, see the article How long do braces hurt? Pressure points, aligner edges, and attachments: What is normal? In the first few days, your tongue and lips will explore the new edges. Slight rubbing at the gum line or against the cheek is common and usually subsides after a few days. Attachments are small, tooth-colored anchor points made of composite resin that we bond to individual teeth when needed. Without the aligner in place, they may feel rough against your lip at first. The aligner fits more tightly over the attachments, which is why removal is more difficult in the first few days. What is not normal is a spot where the aligner repeatedly cuts in. Here is how to recognize a pressing edge: The sore spot is located exactly where the aligner edge ends. It burns when you insert the aligner and gets better when the aligner is out. Your tongue keeps finding the same sharp corner. You may carefully smooth a single sharp edge yourself: with a clean, fine nail file, only the edge, not the inner surfaces. If the aligner continues to cut in afterward, please have the fit checked. Lisping with aligners: How long does the adjustment take? The aligner also covers the inside of your teeth, and your tongue has slightly less space there at first. A systematic review of seven studies describes mainly altered S-sounds and sibilants (Ali Baeshen et al., 2023). Most patients spoke normally again after 7 to 14 days; some needed 30 to 60 days. Tip: Speak often with the aligner in place and read aloud for a few minutes each day. If S-sounds and sibilants still feel noticeably difficult after two weeks, mention it to us at your next appointment; we will then check the fit. What helps with the pressure in the first days with aligners? Change to new aligners in the evening: The initial pressure will then fall during sleep. Continue wearing the aligner consistently despite the feeling of pressure. Breaks tend to prolong the adjustment period. Use your aligner chewies: They help the aligner seat fully, and that often relieves the pressure. Eat soft foods in the first few days, such as soup, pasta, or yogurt. Cooling helps many people, and you may drink cold water even with the aligner in place. If that is not enough, a mild pain reliever can help temporarily, provided there are no contraindications; if in doubt, ask us or your pharmacy. When are symptoms with aligners no longer normal? When you should contact us: The pressure does not subside after several days, or the pain becomes stronger from day to day instead of weaker. A single tooth throbs severely, or a spot bleeds or becomes inflamed. The aligner stands away from individual teeth, suddenly feels loose, or has a crack. An attachment has come off. This is not an emergency: continue wearing your aligner as usual, note or photograph which tooth it was on, and let us know briefly. We can reattach it in a few minutes. If it remains missing for longer, the planned tooth movement at that location may proceed more slowly. The temporomandibular joint hurts in front of the ear, starts clicking, or the mouth opens less easily. If an aligner is lost or broken, reinsert the previous one and call us. Do not continue wearing an aligner with a sharp broken edge. What to do in each case is also explained on our page First Aid for Braces. If a throbbing tooth is accompanied by swelling or fever, or if it hurts at night, this does not fit the pattern of aligner pressure. In that case, please call us; outside office hours, the dental emergency service can help. Pressure from aligners: How we support you at JUST KFO In our orthodontic practice in Cologne, one of three specialists in orthodontics plans every aligner treatment personally. Since 2001, we have supervised over 8,500 aligner treatments. Since 2019, our in-house master dental laboratory fabricates our own aligners. If an edge presses on these aligners, the laboratory refines it. If one is lost or breaks, a new one is made there, usually within a few days. In our professional publication on the workflow in our own laboratory, we describe a straight, polished aligner edge instead of a scalloped one that follows the gum line. According to the publication, this improves force transmission without compromising wearing comfort (Schupp et al., 2020). Approximately every six to eight weeks, we examine your teeth and check whether they are following the plan. We examine the temporomandibular joints already during the initial consultation. With our focus on TMD therapy – for temporomandibular disorder – we look closely when symptoms appear there. If you have questions about your aligner or aligner treatment, feel free to contact us. More on this topicAligner and clear braces in CologneWhat a discreet aligner treatment can achieve, how it is planned and who it is suitable for. Go to Clear Braces Sources: Ali Baeshen, H., El-Bialy, T., Alshehri, A., Awadh, W., Thomas, J., Dhillon, H., & Patil, S. (2023). The effect of clear aligners on speech: A systematic review. European Journal of Orthodontics, 45(1), 11–19. doi:10.1093/ejo/cjac018 Almasoud, N. N. (2018). Pain perception among patients treated with passive self-ligating fixed appliances and Invisalign aligners during the first week of orthodontic treatment. Korean Journal of Orthodontics, 48(5), 326–332. doi:10.4041/kjod.2018.48.5.326 Caldas, W., Bonin, F. A., Vianna, C. P., Shimizu, R. H., & Trojan, L. C. (2024). Influence of pain duration and severity on oral health-related quality of life and patient satisfaction during adult treatment with clear aligners. Progress in Orthodontics, 25(1), 18. doi:10.1186/s40510-024-00514-6 Cardoso, P. C., Espinosa, D. G., Mecenas, P., Flores-Mir, C., & Normando, D. (2020). Pain level between clear aligners and fixed appliances: A systematic review. Progress in Orthodontics, 21(1), 3. doi:10.1186/s40510-019-0303-z Gao, M., Yan, X., Zhao, R., Shan, Y., Chen, Y., Jian, F., Long, H., & Lai, W. (2021). Comparison of pain perception, anxiety, and impacts on oral health-related quality of life between patients receiving clear aligners and fixed appliances during the initial stage of orthodontic treatment. European Journal of Orthodontics, 43(3), 353–359. doi:10.1093/ejo/cjaa037 Kaur, K., Quadri, S. A., Saini, R. S., Alarcón-Sánchez, M. A., & Heboyan, A. (2026). Comparative impact of clear aligners versus fixed orthodontic appliances on periodontal health, pain, and quality of life: A systematic review and meta-analysis. BDJ Open, 12(1). doi:10.1038/s41405-026-00450-z Schupp, W., Funke, J., & Haubrich, J. (2020). Der digitale Workflow in der In-Office-Alignertherapie. Informationen aus Orthodontie & Kieferorthopädie, 52(4), 289–300. doi:10.1055/a-1241-9967 White, D. W., Julien, K. C., Jacob, H., Campbell, P. M., & Buschang, P. H. (2017). Discomfort associated with Invisalign and traditional brackets: A randomized, prospective trial. The Angle Orthodontist, 87(6), 801–808. doi:10.2319/091416-687.1 Frequently Asked Questions About Pain with Aligners May I take a painkiller for aligner pressure? For a short time, yes, if cooling and soft food are not enough and there are no contraindications. If in doubt, ask us or at the pharmacy. If you still need a painkiller after a few days, please have the fit checked. Does the first aligner press the most? Often, yes. In a randomized study, the feeling of pressure after appointments one and two months later was consistently lower than at the start of treatment (White et al., 2017). At the beginning, edges and attachments are also still new to lips and tongue. May I remove the aligner if it presses? Better not. Aligners work only if you wear them 22 hours a day, and breaks tend to prolong the adjustment period. The aligner comes out only for eating, brushing your teeth, and drinks other than water. How long does one lisp with aligners? Usually one to two weeks. In a systematic review, most patients spoke normally again after 7 to 14 days; some needed 30 to 60 days. Do attachments hurt? Bonding them does not hurt: no drilling is involved, and anesthesia is not necessary. Without the aligner in place, the small bumps initially feel rough against the lip; with the aligner inserted, they are covered. Book Appointment Now These blog posts might also interest you.