Human Body Systems: Respiratory, Circulatory, Reproductive, and Nervous
Respiratory System
Types of Respiration
External Respiration: Exchange of gases between the atmosphere and the blood.
Internal Respiration: Exchange of gases between the blood and the body’s cells.
Breathing
Breathing: Mechanical movement of air into and out of the lungs.
Respiratory System Functions
- Gas exchange
- Gas delivery to body cells
- CO2 expulsion from the body
- Oxygen utilization in cells to produce ATP
Air Pathway
Nasal passages, pharynx, larynx, trachea, bronchi, bronchioles, alveoli, blood, cells.
Inhalation
Read MoreOrthodontic Relapse and Retention: Strategies for Maintaining a Beautiful Smile
Why Retention is Needed
Gingival and periodontal tissue require time post-treatment to reorganize. Soft tissue pressures are likely to cause relapse if teeth are placed in an unstable position. Growth post-treatment may also cause relapse.
Timing of Tissue Reorganization
- PDL: 3-4 months
- Collagenous gingival fibers: 4-6 months
- Elastic supracrestal fibers: 1 year
Basic Theories of Relapse and Retention
1. Relapse is less likely if corrections are made during times of growth.
- Influence of growth of the maxilla
Dental Treatment Considerations for Patients with Medical Conditions
Risk Assessment and Treatment Modification in Dentistry
Risk Assessment
Risk assessment involves evaluating at least four components:
- Nature, severity, and stability of the patient’s medical condition
- Functional capacity of the patient
- Emotional status of the patient
- Type and magnitude of the treatment plan and procedures (invasive or not)
Treatment Modification
Preoperative
- Prophylactic antibiotics prior to certain dental procedures in patients at risk for bacterial endocarditis.
- Ensure food intake before
Understanding Periodontal Pockets: Causes, Symptoms, and Treatment
Periodontal Pocket
A periodontal pocket is a pathologically deepened gingival sulcus.
Suprabony Pocket
- Base of pocket is coronal to the crest of the bone (horizontal bone loss).
- Interproximally, transseptal fibers are arranged horizontally.
- Periodontal ligament (PDL) fibers are arranged in their normal pattern.
Infrabony Pocket
- Apical to the crest of the bone (vertical/angular bone loss).
- Interproximally, transseptal fibers are arranged obliquely (angular pattern).
Classification
- Number of Sites: Simple,
A Comprehensive Guide to Human Tissues: Bone, Cartilage, Blood, and Skin
Bone, Cartilage, and Blood
Bone
A bone is a rigid organ that constitutes part of the vertebrate skeleton. Bones have several vital functions:
- Support and protect various organs
- Produce red and white blood cells
- Store minerals
- Provide structure and support for the body
- Enable mobility
Cartilage
Cartilage is a firm, whitish, flexible connective tissue found in various forms in the:
- Larynx and respiratory tract
- Structures such as the external ear
- Articulating surfaces of joints
Blood
Blood is the red liquid that
Read MoreThe Nervous System: Structure, Function, and Development
1. Evolution of the Nervous System
The first single-celled animals, or protozoa, were primitive and exhibited irritability. When evolution led to the emergence of multicellular organisms, or metazoans, specialized cells appeared for intercellular communication. These cells were responsible for the organisms’ irritability. The main function of this early nervous system was the perception of stimuli and the generation of simple responses. As the nervous system evolved, a more sophisticated communication
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