The dental assistant is integral to the success of nearly every clinical procedure by managing the oral environment through aspiration, often called suctioning. This process involves the continuous removal of fluids, debris, and aerosols from the patient’s mouth, which maintains an unobstructed field of view for the dentist. Effective suctioning is necessary for patient safety, preventing aspiration of water or debris, and is directly linked to the quality of restorative work, which requires a dry working surface. The assistant’s skill in moisture control is a foundational element of four-handed dentistry, ensuring procedural efficiency and patient comfort.
Essential Equipment and Pre-Procedure Setup
Dental suctioning relies on two primary tools: the High-Volume Evacuator (HVE) and the Saliva Ejector (SE). The HVE is a powerful tool with a wide bore that removes large volumes of fluid, solid debris, and blood, and is necessary during procedures that generate significant water spray, such as when the high-speed handpiece is used. Its high airflow rate is also highly effective at capturing up to 98% of airborne aerosols at the source, which is important for infection control.
The Saliva Ejector is a low-volume device used for continuous, gentle removal of pooling saliva and water during less invasive procedures like exams, cleanings, or when applying fluoride.
Before any patient is seated, the assistant must select the correct HVE tip, which may include standard operative tips or smaller surgical tips. It is also important to ensure the entire suction system is functional, checking for adequate vacuum pressure and confirming that the disposable traps and lines are clear.
Proper Grasp and Assistant Positioning
The dental assistant uses specific hand grasps to hold the HVE, which allows for maximum control and stability during the procedure. The Pen Grasp is one common method, resembling how one holds a writing pen, using the thumb, index, and middle fingers to lightly control the device. This provides excellent tactile sensitivity for delicate movements and is suitable for most general procedures.
Alternatively, the Thumb-to-Nose Grasp involves securing the HVE in the palm, with the thumb positioned near the on/off switch, offering a firmer hold. This grasp provides greater leverage, making it the preferred choice when the HVE tip must be used to retract the patient’s cheek or tongue for an extended period.
The assistant’s physical positioning is just as significant, requiring a straight back and flat feet, typically sitting at the 3 o’clock position relative to the patient. The assistant should also sit slightly higher than the dentist to ensure a clear line of sight and optimal access to the oral cavity.
HVE Technique: Placement, Function, and Retraction
Effective HVE technique begins with the assistant placing the suction tip into the patient’s mouth immediately before the dentist introduces the handpiece or mirror. The HVE tip’s beveled opening should always face the surface of the tooth or hard tissue to prevent the tissue from being inadvertently sucked into the vacuum, which would cause discomfort or injury.
The primary function of the HVE is to remove the water spray and debris generated by the high-speed handpiece as quickly as possible. To achieve this, the tip is positioned on the same side of the mouth where the work is being performed, keeping it close to the working area without obstructing the dentist’s view or access.
A good rule of thumb is to place the HVE tip one tooth distal, or posterior, to the tooth being worked on, and slightly toward the lingual or buccal surface where fluids naturally pool. For procedures on the mandibular arch, the tip is placed on the lingual side to control the tongue and collect saliva. When working on the maxillary arch, the tip is typically placed on the buccal or palatal side, depending on the operator’s access.
The HVE tip also serves a secondary role as a soft tissue retraction tool, gently holding the cheek, tongue, or lip away from the operative site. This retraction provides the dentist with a better view and protects the soft tissue from being injured by rotating instruments. As the procedure moves across different quadrants, the assistant must continuously adjust the HVE position, ensuring the bevel remains parallel to the tooth surface and slightly higher than the occlusal edge. This effectively anticipates the accumulation of water and debris to maintain a clean, dry, and visible field.