What separates periodontitis from gingivitis
Periodontitis begins when inflammation crosses out of the gum tissue and starts destroying the supporting structures around the root: the alveolar bone and the periodontal ligament. That is the entire difference, and it is a permanent one. Gingivitis is reversible; periodontitis is controllable.
As the attachment breaks down, a space called a periodontal pocket forms between root and gum. Pockets are deeper than a toothbrush can reach, so they collect bacteria, which deepens the pocket further. This self-feeding loop is why the condition accelerates once established.
Reading the numbers your dentist calls out
During a periodontal examination we measure pocket depth in millimetres at several points around each tooth. Those numbers are the clearest way to understand your own situation:
| Pocket depth | Interpretation | Typical approach |
|---|---|---|
| 1–3 mm | Healthy or gingivitis only | Routine cleaning + home care |
| 4–5 mm | Early periodontitis; attachment loss has begun | Deep cleaning below the gumline |
| 6–7 mm | Moderate; not cleanable at home | Deep cleaning, possible surgical access |
| 8 mm + | Advanced; tooth may be mobile | Surgery, or planned extraction if unsalvageable |
How it presents
- Gums that recede, making teeth look longer and exposing sensitive root surface.
- Persistent bad breath or a metallic taste that returns within hours.
- Teeth that feel loose, shift position, or change how they meet when you bite.
- Pus or discharge at the gumline when pressed.
- Food packing into new gaps between teeth that were not there before.
Treatment is staged, not a single procedure
- Non-surgical deep cleaning. Calculus is removed from the root surface below the gumline, usually with local anaesthetic and often split across several appointments by area.
- Re-evaluation. Pockets are re-measured after healing, typically four to eight weeks later. Many patients need nothing further.
- Surgical access for pockets that remain too deep to clean — the gum is reflected so the root can be cleaned directly, then repositioned.
- Maintenance. This is the part that decides long-term outcome. Periodontitis is a chronic condition; three-to-four-month recall is standard for treated patients, not optional.
Why it matters beyond your mouth
Periodontitis is a chronic inflammatory condition with a large surface area of infected tissue. Established associations exist with cardiovascular disease, poorly controlled diabetes, and adverse pregnancy outcomes. The relationship with diabetes runs both ways: uncontrolled blood sugar worsens gum disease, and active gum inflammation makes blood sugar harder to control.
If tooth loss has already occurred, replacement options and their costs are listed on our English price page, and implant treatment is explained here. Note that implants placed in previously periodontal sites require the gum disease to be controlled first — otherwise the same bacteria attack the implant.