Cairo classification is a clinical system used to describe gum recession (gingival recession) in a standardized way. It groups recession defects into categories based on whether there is attachment loss between teeth (interdental clinical attachment loss). Dentists and periodontists commonly use it during periodontal examinations and when discussing root coverage planning. It helps clinicians communicate findings clearly in charts, referrals, and research.

Miller classification is a clinical system used to describe gum recession (gingival recession) around teeth. It groups recession into Classes I–IV based on how far the gum has moved and what support tissues remain. Dentists and periodontists commonly use it during periodontal (gum) examinations and treatment planning. It helps communicate findings in a standardized way across clinicians, patients, and records.

gingival recession is the apical (downward) shift of the gum margin that leaves more tooth or root surface exposed. It is a clinical finding, not a single disease, and it can occur with or without periodontal disease. It is commonly discussed in general dentistry and periodontics because it can affect comfort, aesthetics, and cavity risk on roots. Clinicians use the term to describe what they see, measure it over time, and communicate treatment options.

CAL is a term some dental teams use to refer to a light-cured, resin-based composite material used in conservative restorations. It is commonly associated with a “flowable” or “injectable” composite layer placed to adapt to small spaces and fine details. CAL is used in everyday restorative dentistry for small fillings, repairs, and as a thin liner under other composite materials. Exact meaning and product selection can vary by clinician and case.

clinical attachment level is a clinical measurement that estimates how much periodontal (gum and supporting) attachment a tooth has lost or gained. It is most commonly measured with a periodontal probe during a gum examination. It helps describe periodontal disease severity more consistently than pocket depth alone. It is used in patient records, periodontal charting, and periodontitis staging/grading discussions.

PD is a shorthand term that may appear in some dental notes to refer to a tooth-colored, resin-based restorative material used for direct repairs. In this article, PD refers to a light-cured resin composite placed directly onto a tooth to restore or seal small areas. PD is commonly used in routine restorative dentistry for small fillings, repairs, and as an adaptation layer under other composites. The exact meaning of PD can vary by clinic, charting system, and manufacturer terminology.

probing depth is a measurement of how deep the space is between the gum and the tooth (or implant). It is measured with a thin, marked instrument called a periodontal probe during a gum exam. Clinicians use probing depth to help assess gum health and detect periodontal (gum) disease. It is commonly recorded as part of a periodontal charting at dental checkups and hygiene visits.

BOP most commonly refers to a **bite-opening pad** used in orthodontics. It is a small, raised addition of tooth-colored resin placed on selected teeth to **change how the bite contacts**. BOP is commonly used during **braces or clear aligner treatment** to create space and reduce unwanted tooth-to-tooth or tooth-to-bracket contact. The material is often a **light-cured composite resin**, similar in broad category to many filling materials.

bleeding on probing is bleeding that occurs when a clinician gently inserts a periodontal probe along the gumline. It is recorded during periodontal (gum) examinations in dental offices and clinics. It is used as a clinical sign of inflammation in gum tissues around teeth and implants. It is typically documented site-by-site during periodontal charting.

supragingival calculus is hardened dental plaque (often called “tartar”) that sits **above the gumline** on tooth surfaces. It forms when soft plaque mineralizes, becoming a rough, firmly attached deposit. It is commonly seen on teeth near salivary duct openings and around areas that retain plaque. Clinically, it is used as a descriptive finding during dental exams and cleanings.