dental hygiene theory final exam

How is a properly positioned patient positioned during instrumentation? 

• Positioning: The patient should be positioned so that the oral cavity is at the clinician's elbow level. The backrest should be nearly parallel to the floor for maxillary arch instrumentation and slightly raised for mandibular arch instrumentation. Patient should be in a supine position; brain is at the same level as the heart.  

• Head: Tilt the patient’s head to provide the best access to the working area. 

2. Clock Positions for Operators and Assistants 

• Right-Handed Operator: Typically positioned between 7 to 12 o’clock. 

• Left-Handed Operator: Typically positioned between 12 to 4 o’clock. 

• Dental Assistant: Positioned at 2 to 4 o’clock (right-handed operator) or 8 to 10 o’clock (left-handed operator). 

• Static Zone- is positioned at 12 to 2 o’clock. 

• Transfer Zone- is positioned at 4 to 7 o’clock located across the patient’s chest.  

3. Proper Instrument Transfer Technique 

• Use the "hidden transfer" technique where instruments are handed with the working end positioned for immediate use. Always place the instrument firmly into the operator's hand to avoid dropping. *Always pass instruments across the patient’s chest, never behind or over the face.  

• Assistant right hand is free to use for oral evacuation or retraction. 

• Where is the transfer zone located? -over the patient’s chest  

• Deliver instrument with positive pressure 

• Assistant chair is leveled 4-6 inches higher than the operator.  

• When suctioning, make sure to place the suction before operator goes in with their instrument.  

What is the sequence for instrument transfer?  

Approach -grasp end opposite than held by operator (if operator is left-handed, assistant will use right hand; if operator is right-handed, assistant will used their left hand.)  

Retrieval - pinky finger will grasp unwanted instrument 

Delivery -assistant lowers new instruments into the operator's hand.  

4. Parts of the Aspirating Syringe 

1. Thumb Ring: For control during aspiration and injection. 

2. Finger Rest: Stabilizes the syringe. 

3. Barrel: Holds the cartridge. 

4. Harpoon: Engages the rubber stopper of the cartridge for aspiration. 

5. Piston Rod: Pushes the anesthetic out. 

6. Needle Adapter: Holds the needle in place. 

5. Needle Terms 

• Lumen: The hollow core of the needle through which anesthetic is delivered. 

• Gauge: The diameter of the needle; the lower the number, the larger the diameter (ex. 25-gauge is larger than 30-gauge). 

• The more zeros the smaller the gauge. (Suture needle) 

7. Radiographic Terms 

What are the uses of dental radiographs? -detect disease not detected clinically, confirm or classify suspected lesion, provide information during treatment, evaluate growth, give a baseline, and show caries/perio/or trauma.  

How do caries/periodontal disease appear on the radiograph? – radiolucent  

• Radiolucent: structures that appear dark or black on radiographs  

-pulp  

-caries  

-abscesses 

-periapical disease  

-nutrient canals 

-lingual foramen  

-mental fossa  

-mental foramen  

-mandibular canal  

-submandibular fossa  

-median palatine suture  

• Radiopaque: structures that appear light or white  

-enamel 

-restorations, composites  

-bone 

-genital tubercles 

-mental ridge  

-coronoid process  

-lamina dura: radiopacity outlining the tooth root  

-missing teeth/supernumerary teeth 

Common Errors: 

• Foreshortening: excessive vertical angulation. Too high  

• Elongation: insufficient vertical angulation. Too low  

• Cone Cut: failure to center the x-ray beam. 

• Superimposition (overlapping): incorrect horizontal angulation 
  • Partial Image: cone-cut, 
  • For non-digital incompletely immersed in processing tank, film touched another during 
  processing 
  • Missing root apices: film or sensor not placed properly, patient not closing on bite-block. 

• Density: degree of darkness exposed on a film 

• Contrast: visual differences in image density of the light and grey tones appearing on a film  

• Low kVp: high contrast best for detection of caries.  

• High kVp: low contrast best for detection of periodontal disease.  

• To get a higher contrast you would need to? Lower the KVp  

7. Root Planning vs. Scaling/Periodontal Debridement 

• Root Planning: Smoothing the root surface to remove residual calculus and cementum. 

• Scaling/Periodontal Debridement: Removal of calculus and plaque from tooth surfaces without smoothing roots. 

• Scaling and root planning includes the intentional removal of the cementum. 

• It creates a glassy smooth root surface this is the end point of tooth planning. 

8. Treatment Planning for Scaling and Root Planning 

What is periodontal debridement? -the removal or disruption of bacterial plaque and plaque retentive calculus depots from coronal surfaces, root surfaces, and with the pocket space and tissue wall, to promote periodontal healing and repair.  

• Start with the most involved quadrant. 

• Treat one side of the mouth (e.g., upper and lower right quadrants) to reduce post-treatment discomfort and allow for easier patient chewing. 

9. Determining the Endpoint for Root Planning 

How do you determine the end point for root planing? 

• The endpoint is achieved when the root surface feels glassy smooth and is free of calculus or residual deposits. 

10. Importance of Using Sharp Instruments 

• Reduces clinician fatigue. 

• Enhances precision. 

• Prevents tissue trauma. 

• Improves patient comfort. 

11. Gingival Curettage 

*The purpose of gingival curettage is to reduce inflammation and improve healing so that there is a reduction in pocket depth. It is one of the oldest periodontal methods.  

      -Following gingival curettage, healing begins with blood clot formation.  

• Appropriate: when inflamed gingival tissue needs to be removed to aid healing. 

Types of Gingival Curettage: 

• Inadvertent -soft-tissue curettage removes sulcular epithelium unintentionally. 

• Intentional- diseased and inflamed soft tissue of the sulcular epithelium is removed intentionally 

• Chemical- Combines scaling and root planning with a chemical solution to remove diseased soft tissue from periodontal pockets.  

• Neutrophils are the most common blood cell to promote healing the gingiva 12 hours after soft tissue curettage is performed. Life span of about 3 days.  

• Indications for Curettage: 

• Soft, spongy, edematous gingiva 

• Gingival or supra-bony pockets 

• Inflammation that persists in spite of plaque control or scaling and root planing 

• Contraindications: healthy tissue, fibrotic tissue, or systemic health conditions (ex. uncontrolled diabetes), ANUG, insufficient attached gingival and mucogingival involvement, periodontal inflammatory lesions.  

• What type of pocket is soft tissue curettage most indicated? -supra bony pocket 

• Gingival curettage eliminates pocket alone by : 

Shrinkage, new attachment, and formation of a long junctional epithelium  

12. Types of Power Scalers 

1. Magnetostrictive: Elliptical tip movement; all surfaces active. 20,000 to 42,000 cps  

2. Piezoelectric: Linear tip movement; lateral surfaces active. 29,000 to 50,000 cps  

3. Sonic: elliptical or orbital (circular motion) tip movement driven by compressed air; lower frequency. 2,500 to 7,000 cps  

• Cavitation: the implosion of bubbles in the water spray (halo effect), which disrupts bacteria. 

13. Correct Ultrasonic Tip Adaptation 

• Adapt the side of the tip to the tooth, keeping it at a 0-15° angle. 

14. Instrument Selection 

• Use specific instruments based on area and deposit type:  

• Universal curettes: can be used on all tooth surfaces. (ex. Barnhart and Youngergood)  

• Gracey curettes: area-specific for specific regions (ex. Gracey 11/12 for mesial surfaces). 

• Instruments You Might Encounter 
  Universal Curets: 
  Columbia 4R/4L- Heavy to medium universal curet; good for general scaling and root planing 
  Columbia 2R/2L- Universal with long shank and short blade; similar to newer mini-bladed curets 
  Columbia 13/14- Very small short blade; too short for deep posterior perio pockets 
  McCalls’s 17/18- Large universal curet; wide curved blades (curved like a Nabors probe); for 
  heavy calculus in 4-6 mm pockets with loose tissue 
  Younger-Good 7/8- Medium universal curet; smaller version of the McCall’s 17/18; curved 
  blades (like a Nabors probe); for general scaling and maintenance 
  Loma Linda 10-11- Medium universal curet; similar to Barnhart ½ but not as curved; longer, 
  flatter blade adapts well to buccal and lingual surfaces (deep palatal pockets) and line angles   
  Goldman-Fox 4- Large heavy universal curet; long lower shank (like and After 5); very good for tenacious calculus on distals of molars 
  Barnhart 1/2 or 5/6 ; good perio maintenance and general use curet 
  Gracey Curets: 
  Regular Graceys- for fine scaling and root planing, flexible shanks 
  Rigid Graceys- for heavy scaling and root planing 
  Extra Rigid Graceys- for tenacious calculus; initial preparation quadrant scaling and root planing 
  Gracey 15/16- Gracey 11/12 blade on a 13/14 shank; for mesials posteriors, esp. good for 
  mesials of molars 
  Gracey 17/18- Modified Gracey 13/14; for distals of molars; longer, angled shank, blade is 1 mm 
  shorter 
  After Fives- Regular or rigid or extra rigid; 3 mm longer in lower shank; good for deeper 
  posterior pockets, esp. second and third molars 
  Mini Fives- Regular for maintenance or rigid for initial quadrant scaling; for furcations, line 
  angles, deep narrow pockets, concavities or depressions, CEJ areas 
  Gracey Curettes: 
  Curette Sub-0- good for deep maxillary and mandibular anterior pockets and palatal aspect of 
  maxillary anteriors 

15. Mouthrinses and Antibacterial Agents 

• Chlorhexidine Gluconate: effective against plaque and gingivitis, may stain teeth. 

• Contraindications: allergy to ingredients or alcohol in the formulation. 

• Side Effects of Chlorhexidine:  

-tooth/tongue staining 

-supra calc formation  

-slight burning sensation on the mucosa  

-altered taste perception  

16. Waterpik Technique 

• Direct the tip at a 90-degree angle to the gumline. 

• Use low to moderate pressure for best results. 

• Depth of fluid penetration for a water flosser is 6 mm.  

• Does not replace flossing routine, can be used as an irrigator and good for deep pockets for periodontal disease.  

17. Dental Dam 

• Purpose: isolate the operative site, maintain a clean field, and protect soft tissue 

• Indications (reasons to use): Improves safety, visibility, and eliminates inconvenience of accumulations of saliva and tongue movement.  

• Contraindications: latex allergy, respiratory issues. 

• Disadvantages: clamp may be irritating to gingiva, possible latex allergy, time consuming for beginner operator. 

• Review Procedure for placement of dam 

• Ligate Dam Clamp: floss attached to clamp in order to prevent swallowing or aspiration if the clamp detaches. 

• Anchor Tooth: One or two teeth distal to the working tooth. 

• Seating: Edges of dam should be inverted around the lingual and facial surfaces. The clamp is seated at the cervical area below the height of contour one or two teeth distal to the working tooth. 

• Dental Dam Template: punch holes to fit the teeth 

• Rubber Dam Punch: used to punch the holes into the template.  

• Rubber Dam Forceps: used to clamp the dental clamp onto the tooth. 

• Dental Dam Frame: small projections on the frame allow for the material to stretch  

18. Matrix Retainer 

• Purpose: maintain tooth shape during restoration and replace wall of interproximal prep for restoration placement. Prevents deformation of restorative material. Prevent gingival overhangs or cupping. 

• Which Class would require the use of a matrix retainer? Class II  

• Facial vs. Lingual Placement: Depending on the location and access needed. 

• Larger circumference always toward the occlusal edge and smaller circumference always toward the gingiva.  

• Proper Placement: Tight against the gingival margin to avoid overhangs. 

• Materials that is being used Tofflemire Retainer  

• Matrix Band- metal or plastic- used to replace the missing wall of a tooth during placement of restorative material.  

• Steps for Placement: 1.Rubber dam is placed prior to retainer. 2.Determine size of matrix for correct procedure. 3.Assemble retainer and matrix for correct quadrant and tooth. 4. Position band and retainer on prepped tooth. Turn inner knob clockwise to tightened band around tooth. Select proper size wedge and place.  

• (Removal)1. After restoration is carved, remove wedges. 2.Loosen retainer from matrix band and remove.3. Remove band from tooth with cotton pliers gently to prevent fracturing restoration. 

• Problems that can occur (Band too tight lacking contour) (Band too loose causing over contour) 

• Wedges- (wood or plastic), holds matrix against tooth separates teeth slightly forms contact to prevent overhangs, Triangular in shape (based towards gingiva), Placed lingual to buccal  

• Problem with Wedges 

• Improper placement- overhang in the 
  restoration. 
  2. Wedge not placed firmly enough to 
  slightly separate teeth- will not provide 
  proper contact with the adjacent tooth. 
  3. Matrix not wedged properly- restorative 
  material will not provide the desired 
  contact, contour and protection of the 
  interproximal gingiva 
  Properly placed 
  wedge (snugly) 

• Larger circumference always toward the occlusal edge  

• Smaller circumference always toward the gingiva  

• Extend 1-2 mm occlusally  

19. Periodontal Dressing 

• Reasons for Use: protect surgical sites, minimize discomfort, and stabilize the clot. 

• Types: eugenol (anti-bacterial) and non-eugenol(better option). Coe-Pak is non-eugenol and most commonly used.  

• Post-Operative instructions: Left for 7-10 days, only brush the occlusal surfaces of the teeth, use a saline rinse every 2-3 hours on the second day, eat a soft high-protein diet, do not suck on straw, brush and floss in untreated areas, do not smoke, take prescriptions as directed, use ice pack to reduce swelling.  

20. Suture Placement and Removal 

• Atraumatic Needle: Minimizes tissue damage. 

• Suture Types: simple: interrupted, continuous: mattress. 

• Post operative instructions: written/verbal, bite on gauze for 30 mins, apply ice pack to reduce swelling, do not spit/smoke/or suck on straw for 24 hours, beginning the day after surgery rinse with warm saline solution, review all Rx written by doctor.  

• Type of Suture Material: absorbable dissolve and become absorbed by the body’s enzyme during healing, nonabsorbable must be removed in 5-7 days  

• Characteristics of Suture Material: braided, twisted, plain  

• Always document the location of the sutures, how many sutures, and all sutures should be accounted at the time of removal in the patients chart.  

• Nonabsorbable sutures- must be removed in 5-7 days after 
  surgery. 
  • Examples: 
  • Silk- used for it’s strength and easy application 
  • Polyester fiber- one of the strongest sutures 
  • Nylon- used for its strength and elasticity 
  • Wire 

21. Gingival Retraction 

• Purpose: temporarily displace gingival tissue and widen gingival sulcus so that impression material can flow around all parts of the preparation. 

• Types: cord retraction, chemical retraction (most common), and mechanical. 

• Contraindications: Thin or delicate tissue and precautions of epinephrine  

• When is tissue retraction performed? After tooth is prepared, just before final impression is taken and left in for 5-10 minutes 

• Expa-syl contains aluminum chloride to control bleeding crevicular seepage 

• (injectable retraction material injected into the sulcus) 

22. Exfoliative Cytology and Biopsy 

When should exfoliative cytology be used and what are the limitations? 

• It is used to help the patient determine the diagnostic of what specific bacteria is causing the disease-Perio or gingivitis? 

• Limitations can produce false or positive results, sampling error, cannot penetrate into deeper tissues.  

• Exfoliative Cytology: collects surface cells; limited diagnostic accuracy. 

• Biopsy: gold standard for diagnosing suspicious lesions. 

• Gram positive (stains purple) is mostly SUPRA and Gram-negative bacteria is mostly SUB and leads to perio disease (stains pink/red) 

• Early colonizers are gram positive and are streptococcal species 

• Intermediate colonizers mostly cocci and rods (rods begin to outnumber cocci) 

• Red complex bacteria are most detrimental in periodontal disease. 

• Gram Staining Order: Crystal Violet, Iodine, Alcohol, Safranine 

   

23. Orthodontic Placement and Removal 

How to size and place a band, and the advantages and disadvantages of bonded appliances over cemented bands. 

• Archwire can be sized with used archwire and study model 

• Separator Placement is used: create space to ease the placement of orthodontic bands  

• Bonded Appliances: Advantages: better aesthetics and comfort. Disadvantages: Risk of enamel demineralization. 

• Archwire: Matches the arch dimensions and helps with tooth movement.  

• Elastomere: holds wire in brackets and applies forces to close spaces between teeth.  

• Patient must return 4 weeks-8 weeks for adjustment.  

• OHI Instructions 

-Floss teeth using a floss threader  

-Brush teeth at least once every day  

-After brushing, rinse and swish water around to remove any debris  

-Inspect your teeth and braces carefully to make sure they are clean.  

-Use good sense in selecting foods that won’t loosen or pop off a bracket or bend the arch wire. (avoid sticky/hard foods)