Diagnosis and oral hygiene assessment
For initial examination and detection of deposits, explorers (single-ended or double-ended probes) are used. Special hygiene indices are used for an objective assessment of the amount of deposits.
Tooth staining makes it possible to perform both qualitative and quantitative evaluation.
Fedorov-Volodkina index Determined using Schiller-Pisarev solution (composition: 1 g of crystalline iodine, 2 g of potassium iodide, 40 ml of distilled water). The dentist stains the vestibular surfaces of the six lower anterior teeth and evaluates them on a 5-point scale:
- 5 points — staining of the entire surface;
- 4 points — 3/4 of the surface;
- 3 points — 1/2 of the surface;
- 2 points — 1/4 of the surface;
- 1 point — no staining.
The hygiene index (HI) is calculated by the formula: the sum of the scores is divided by the number of examined teeth.
- 1.1–1.5 — good condition;
- 1.6–2.0 — satisfactory;
- 2.1–2.5 — unsatisfactory;
- 2.6–3.4 — poor;
- 3.5–5.0 — very poor.
OHI-s index (Greene-Vermillion, 1969) Six adjacent teeth or 1–2 teeth from different groups of the dental arches (vestibular and oral surfaces) are stained. Evaluation is carried out using a 3-point system (from 1/3 to 2/3 of the surface). In case of uneven plaque, the larger volume or the arithmetic mean is taken into account. The formula calculates the index, where 1 represents an ideal condition, and a value greater than 1 indicates poor hygiene.
Methods for removing dental deposits
The removal of deposits is divided into individual hygiene (toothbrushes, dental floss, irrigators) and professional hygiene. Professional hygiene utilizes mechanical, physical, chemical, or combined methods.
Removing calculus requires medications, devices, ultrasonic and sonic scalers, as well as manual instruments (curettes, excavators). The final step is polishing the tooth surfaces using rubber and silicone cups, heads, brushes, and pastes.
Structure of manual instruments Any manual periodontal instrument consists of three elements:
- Handle — for holding the instrument.
- Shank — the connecting part.
- Working end.
The shank is divided into the functional shank (has two bends) and the terminal shank. The functional shank can be short (for anterior teeth and supragingival calculus), medium length, or long (for posterior teeth and periodontal pockets). The terminal shank ensures proper contact of the working end with the tooth.
The anatomy of the working end in cross-section represents a semicircle with a flat base and includes the face (F), lateral surface (I), cutting edge (C), and back (B).
Characteristics of manual instruments
Manual instruments are included in prophylactic kits and are divided into several main types:
- Scaler — has a sharp tip and is used exclusively for supragingival dental calculus. In cross-section, it is triangular in shape, and the angle between the face and the shaft is 90°. They are available as straight and sickle (curved along an arc) types. The working end of a scaler includes a face and two cutting edges.
- Curette — features a rounded tip and is used for removing subgingival deposits.
- Universal curettes have two cutting edges and can be used on all tooth surfaces.
- Area-specific curettes (e.g., Gracey) have only one cutting edge and are designed for strictly specific surfaces.
Instruments with specific designs also include the chisel, file (with multiple serrations), and hoe (an instrument with a single bend where the working end is at a sharp angle to the shank).
Briefly: answers to topical questions
Which specific teeth are stained when determining the OHI-s (Greene-Vermillion) index?
When determining the OHI-s index, 6 adjacent teeth or 1-2 teeth from different groups of the upper and lower jaws are stained. Their vestibular and oral surfaces are evaluated. For quantitative assessment, a three-point system is used, taking into account the stained area from one-third to two-thirds of the surface. In the case of uneven plaque, the evaluation is based on the larger volume or the arithmetic mean of multiple surfaces.
What types are ultrasonic scalers divided into depending on the vibration generation mechanism?
Depending on the mechanism of ultrasonic wave generation, scalers are divided into piezoelectric and air-driven.
- Piezoelectric scalers — ultrasonic vibrations are generated by applying an alternating electric current to a piezoelectric element. The tip oscillates strictly in a single plane at a frequency of up to 35,000 Hz.
- Air-driven scalers — vibrations occur due to the indirect impact of an air stream on the central axis. The tip is subjected to circular vibrations at a frequency of about 7,000 Hz.
To remember the purpose of the instruments: Scaler — Sharp (for supragingival calculus), Curette — Rounded (for pockets / subgingival calculus).
Class and exam questions
What pathomorphological changes are characteristic of the initial stage of periodontitis?
Resorption of the compact lamina of the interdental septum, lacunar resorption, and accumulation of osteoclasts in the bone tissue are observed.
How is the Fedorov-Volodkina index calculated?
Schiller-Pisarev solution is used to stain the 6 lower anterior teeth, each evaluated on a 5-point scale. The index is equal to the sum of the scores divided by the number of examined teeth.
What is the main difference between a scaler and a curette?
A scaler has a sharp tip and is used for supragingival calculus, whereas a curette has a rounded tip and is designed for subgingival work.
What else to study on this topic
- Mechanisms of lacunar resorption and the role of osteoclasts
- Guidelines for working with Gracey area-specific curettes
- Specifics of using staining solutions (Schiller-Pisarev, fuchsine)
- Physical and chemical methods of professional oral hygiene
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Other topics in "Chapter 13. Dental Deposits"
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