Hard Tissue Charting and Classification of Dental Decay Study Notes
Hard Tissue Charting
What We Will Learn
Objective 1: We will discuss the correct ways to keep records of important findings on hard tooth surfaces by using special charting symbols and how we number teeth.
Objective 2: We will learn about the different kinds of dental cavities and other types of damage that can happen to hard tooth tissues.
Objective 3: We will describe the tools and equipment needed for a thorough hard tissue examination.
Objective 4: We will explore various developmental problems that can occur as teeth grow and form.
Understanding Hard Tissue Charting and How Dental Decay is Classified
How Teeth Are Classified
Human Teeth: People have two natural sets of teeth at different stages of life:
Primary Teeth (Baby Teeth):
There are usually up to primary teeth in total.
These teeth are divided with teeth in each of the four sections (quadrants) of the mouth, which include incisors (front teeth), canine (cuspid), and molars (back teeth).
Permanent Teeth (Adult Teeth):
There are usually permanent teeth in total.
These teeth are divided with teeth in each quadrant, including incisors, canine, premolars (bicuspids), and molars.
How We Divide the Mouth: Quadrants and Sextants
Quadrant Classification: The mouth is divided into four quadrants, and each quadrant contains between and teeth, depending on whether the person has primary (baby), mixed (some primary and some permanent), or permanent teeth.
Sextant Classification:
The mouth can also be divided into six sextants, where the front sextants include the incisors and canines.
The back sextants include the premolars and molars.
How We Classify Different Tooth Surfaces
Tooth Root Classification:
The root of a tooth is divided horizontally into three parts:
The apical third, which is closest to the tip of the root.
The middle third.
The cervical third, which is closest to the gum line.
Tooth Crown Classification:
The crown (the visible part of the tooth) is divided horizontally into three parts:
The gingival third, which is closest to the gums.
The middle third.
The incisal (for front teeth) or occlusal (for back teeth) third, which is the biting or chewing edge/surface.
From the front view, the crown is also divided vertically into three parts:
The mesial third, which is closer to the midline of the mouth.
The middle third.
The distal third, which is further away from the midline of the mouth.
How to Ask Patients About Their Symptoms
Patients should provide specific information about:
The location of where they feel the symptoms.
The duration of how long the symptoms have been happening.
Any postural changes that make the symptoms better or worse.
The characteristics of the pain, such as if it is sharp, dull, throbbing, etc.
We should always start asking questions using open-ended questions to encourage patients to share more information.
Understanding a patient's symptoms is extremely important for making an accurate dental diagnosis.
How We Examine Teeth and Find Dental Cavities
Methods used to find dental cavities include:
Direct Visual Examination: Looking directly at the teeth.
Transillumination: Shining a light through the tooth to reveal shadowed areas of decay.
Tactile Clinical Examination: Gently feeling the tooth surfaces, although this method is less recommended nowadays.
Radiographic Evaluation: Using X-rays to see decay between teeth or under fillings.
Evaluation of patient-reported symptoms: Considering what the patient tells us about their discomfort.
Assessing Damage That Teeth Get Over Time
Acquired Tooth Damage: This refers to when a tooth loses its original strength or structure, and it is mainly caused by:
Dental Caries (cavities), which is the most common reason for tooth damage.
Other forms of damage include:
Attrition: Wear caused by tooth-to-tooth contact (grinding).
Abrasion: Wear caused by foreign objects rubbing against the tooth (like aggressive brushing).
Erosion: Wear caused by acids dissolving the tooth structure.
Fracture: A crack or break in the tooth.
A Quick Look at Dental Cavities
Dental Caries (cavities): This is an infection that has many causes, mainly occurring when bacteria act on sugary foods, which then harms the hard, mineralized tissues of the tooth.
Places Most Likely to Get Cavities:
Pits and fissures found on the chewing surfaces (occlusal) and on the cheek (buccal) or tongue (lingual) sides of teeth.
The contact points between teeth (interproximal areas).
Along the gum line (free gingival margin).
Areas of the tooth root that become exposed due to receding gums.
Different Types of Dental Cavities
Early Childhood Caries: These are cavities seen in children who are younger than years old.
Rampant Caries: This is a very fast and widespread destruction of many teeth that needs quick treatment.
Chronic Caries: This is a type of decay that progresses slowly over time and requires dental care.
Arrested Caries: These are lesions that have stopped decaying and have re-hardened (remineralized) when the cavity process is no longer active.
Recurrent Caries: These are new cavities that form either under or around older dental fillings or restorations.
Types of Cavities Based on Where They Are Located
Pit and Fissure Caries: These cavities are found in the natural grooves and uneven surfaces, especially on the chewing surfaces of premolars and molars.
Proximal Caries: These cavities happen in between teeth, at the points where they touch each other.
Smooth Surface Caries: These cavities are located on the flat, smooth surfaces of the teeth, such as the front (facial), cheek (buccal), tongue (lingual), mesial (towards the midline), and distal (away from the midline) surfaces.
Root Caries: These cavities affect the root of the tooth, which includes the cementum or the parts of the tooth near the gum line.
How We Classify Dental Cavities and Fillings
Black Classification System: This is a widely used system to identify the different types and locations of dental cavities, grouped into classes from Class I to Class VI.
Complexity Classification System: This system also identifies cavities and fillings based on how many tooth surfaces are affected.
These classifications include simple (one surface), compound (two surfaces), and complex (three or more surfaces) cavities.
Other Systems for Classifying Cavities
International Caries Detection and Assessment System (ICDAS): This system combines checking a patient's risk for cavities with a clinical examination of tooth surfaces to give specific codes for cavity detection.
International Caries Classification and Management System (ICCMS)
American Dental Association (ADA) Caries Classification System
Methods for Finding Cavities
Visual Assessment: This method involves looking closely at the teeth and gives us information about where the cavity is, its color, and how the surface feels or looks.
Radiographic Assessment (X-rays): This method involves using:
Bitewing radiographs: These X-rays are good for finding cavities between teeth.
Periapical radiographs: These X-rays show the entire tooth, from the crown to the root tip and the bone around it.
Explorer Assessment: Using a sharp dental explorer is generally not recommended anymore because modern practices have changed.
Emerging Technologies: New tools like intraoral cameras (IOCs) are being used more often to help detect cavities.
Damage to the Pulp (Inner Tooth Tissue)
Common Reasons for Damage to the Pulpal Nerve:
Bacterial infections within the tooth.
Trauma (injury) to the tooth, which can lead to painful pus-filled pockets called abscesses.
Endodontics: This is a special branch of dentistry focusing on preventing, diagnosing, and treating problems of the dental pulp and the tissues around the root of the tooth.
Problems That Occur During Tooth Development
Tooth Anomaly: This is a developmental problem that can happen because of issues present at birth, inherited traits, or environmental factors that disrupt tooth development.
Common Types of Developmental Anomalies: These include differences in the total number of teeth or specific changes in the tooth tissues themselves.
How We Chart the Dentition
Charting Process: This process is done when a patient first comes in for an assessment and is updated during all future appointments, and there is no strict order for charting.
Problems with the Number of Teeth
Hyperdontia: This means having extra teeth, such as a mesiodens (an extra tooth located between the two front teeth).
Hypodontia: This means having missing teeth.
Fusion: This happens when two separate tooth buds join together to form one larger tooth.
Problems with Entire Teeth
Macrodontia: This refers to teeth that are larger than normal.
Microdontia: This refers to teeth that are smaller than normal.
Germination: This involves a single tooth bud trying to divide, resulting in a tooth that appears double or twinned.
Dilaceration: This is an abnormal bend or curve in the root of a tooth.
Problems with Enamel Formation: Enamel Dysplasia
Conditions related to problems with enamel development include:
Enamel Hypoplasia: This occurs when there isn't enough enamel formed on the tooth.
Dental Fluorosis: This is discoloration of the enamel that happens due to getting too much fluoride during tooth development.
Syphilis-Related Enamel Hypoplasia: These are enamel problems linked to a congenital syphilis infection.
Hutchinson Incisors: These are front teeth that have characteristic horizontal notches or indentations.
Mulberry Molars: These are molars that are structurally altered and have a lumpy, berry-like appearance due to syphilis.
Peg Lateral Teeth: These are lateral incisors (the teeth next to the two front teeth) that are unusually small and cone-shaped.
Enamel Hypocalcification: This is when the enamel is softer than it should be, even if there is enough of it.
Amelogenesis Imperfecta: This is a genetic condition that causes the enamel to form incorrectly, making it abnormal in color, shape, and hardness.
Anomalies of Dentin Formation
Dentinogenesis Imperfecta: This is a genetic disorder where the dentin, the layer beneath the enamel, forms improperly.
Dentin Dysplasia: This is another disorder that results in defective dentin, often affecting the root structure.
Taurodontism: This is an abnormality where the tooth has an enlarged pulp chamber and a short root structure, giving it a 'bull-like' appearance.
G.V. Black's Classification System for Cavities and Fillings
The Different Classes of Lesions
Class I to VI: Here are the descriptions and features of each class:
Class I Lesions: These are cavities found on the chewing surfaces of back teeth or in the pits and fissures of any tooth.
Class II Lesions: These cavities are located on the sides of back teeth that touch other teeth (proximal surfaces).
Class III Lesions: These are cavities found on the sides of front teeth that touch other teeth (proximal surfaces), but they do not involve the biting edge.
Class IV Lesions: These cavities are found on the sides of front teeth, just like Class III, but they also include the biting edge of the tooth.
Class V Lesions: These cavities are located on the third of the tooth closest to the gum line, on either the front (facial) or back (lingual) surfaces.
Class VI Lesions: These are cavities found on the very tips of the biting edges of front teeth or on the cusps (pointed parts) of back teeth.
How Dental Hygienists Chart Hard Tissues
Color Coding Symbols:
Red: This color is used on charts to show that a tooth or an area needs treatment.
Blue: This color shows treatments that have already been completed or are already present in the mouth.
Common Charting Symbols
Here is a table of charting symbols that are often used for various dental conditions:
Class I: A symbol is usually drawn in the center of the occlusal surface to represent decay or a filling on chewing surfaces.
Class II: A symbol showing a filling on the mesial/facial surfaces indicates an amalgam filling (silver-colored filling).
Class III: A symbol indicating a filling on the mesial/facial surfaces of a front tooth.
Class IV: A symbol often indicates evidence of a tooth fracture or indicates a gap between teeth (a diastema).
Class V: Symbols indicate restorations located in the cervical/facial area (near the gum line on the front surface).
Symbols are also used for needs like tooth extraction, impacted teeth (unerupted), root canal therapy, and various types of fillings and crowns.
The Process of Keeping Dental Records
Dental Charting: This is a visual record of a patient's dental health conditions observed on a specific date.
Format: These charts can be drawn to look like a realistic tooth (anatomic) or use geometric shapes.
Arrangement: The chart should be set up as if you are looking directly inside the patient's mouth.
Electronic Charting:
Advantages: It saves physical space, allows for easy retrieval of patient records, and can easily include pictures and other media.
Disadvantages: Setting it up can be very expensive, it requires staff training, and there might be potential issues with infection control if not managed correctly.
Example Charts
Example 1: This shows an anatomic diagram used for charting various conditions in the mouth based on the collected data.
Example 2: This example provides a geometric representation that illustrates the status of teeth over time, showing teeth that have been removed and planned treatments for different conditions.