The appearance of new spaces between your teeth, known as diastema, is a common concern that often develops or worsens as people age. This shifting results from cumulative changes over many years within the mouth’s dynamic environment. Although teeth seem solidly anchored, they are suspended in the jawbone by a network of fibers, allowing slight movement in response to various forces. Understanding adult-onset spacing involves examining the foundational support, constant forces, and physical wear that occurs over time.
Periodontal Disease and Bone Loss
The most frequent cause of teeth separation and movement in older adults is a weakening of the structural support system surrounding the teeth. This support system, known as the periodontium, consists of the gums, the periodontal ligament, and the alveolar bone of the jaw. Chronic inflammation from periodontal disease (periodontitis) compromises this anchor.
The disease is triggered by plaque bacteria that cause a persistent immune response, resulting in the slow destruction of the alveolar bone encasing the tooth roots. This bone resorption reduces the height and density of the bony socket responsible for holding the tooth firmly in place. As the supporting bone shrinks, the teeth become increasingly mobile.
The loss of secure anchoring allows teeth to be easily pushed by the normal forces of chewing, swallowing, and the resting pressure of the tongue. This effect can cause teeth, particularly the upper front teeth, to fan out, tilt forward, or drift sideways, creating noticeable gaps. Addressing the underlying periodontitis is the necessary first step, as no cosmetic or orthodontic treatment will be stable without a healthy bony foundation.
Forces from Oral Habits and Soft Tissues
Beyond foundational issues caused by disease, the subtle but constant mechanical forces exerted by soft tissues contribute significantly to spacing. Teeth are highly sensitive to long-term, light pressure, and the combined forces from the lips, cheeks, and tongue act on them throughout the day and night.
One common factor is an incorrect resting posture of the tongue, often associated with an orofacial myofunctional disorder. Ideally, the tongue rests entirely against the palate, but in some individuals, it rests low or presses forward against the back of the front teeth. This constant, light pressure, sustained for hours each day, is sufficient to push teeth apart over time, mimicking the effect of orthodontic appliances.
Another habit that applies pressure is a “tongue thrust,” where the tongue pushes forward between the teeth during swallowing. While the pressure from a single swallow is too brief to move teeth, a forward tongue posture combined with this habit can destabilize teeth that already have compromised bone support. Chronic mouth breathing, often due to nasal obstruction, also contributes by forcing the tongue into a low, forward position that reinforces outward pressure.
Wear, Missing Teeth, and Past Dental Work
Several physical changes related to aging and dental history also directly create or widen spaces between teeth. One such change is dental attrition, the natural wear of the tooth surface from years of chewing and grinding. As chewing surfaces wear down, the overall front-to-back length of the dental arch can slightly shorten, allowing teeth to shift and create subtle spacing.
The absence of neighboring teeth is a powerful cause of tooth movement, a phenomenon known as mesial drift. If a back tooth, such as a molar, is lost and not replaced, adjacent teeth will begin to tilt and drift into the empty space. This migration can disturb the alignment of the entire arch, leading to spacing or crowding in other areas, including the front of the mouth.
If you have a history of orthodontics, teeth shifting may also represent a form of relapse. Teeth have a natural tendency to return to their original positions, requiring long-term retainer use after braces or clear aligners. Insufficient or inconsistent retainer wear allows the periodontal ligaments, which have a “memory,” to slowly pull the teeth back toward their starting alignment, often resulting in new or widening gaps.
Next Steps for Addressing Teeth Separation
If you notice new or increasing spaces between your teeth, the first step should be a comprehensive examination by a dentist or periodontist. Because periodontal disease is a leading cause of adult tooth movement, a professional assessment is needed to diagnose the health of your supporting bone and gums. This process often involves periodontal probing and dental X-rays to measure the extent of bone loss around the roots.
Once the underlying cause is identified, a treatment plan can be developed. A periodontist can address gum health and stabilize the bony foundation, while an orthodontist can determine if the spacing can be corrected with treatment options like clear aligners or braces. If soft tissue habits like tongue thrust are a factor, a referral to an orofacial myofunctional therapist may be recommended to retrain the oral muscles.