Oral surgery introduction



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Relationship of Associated Vital Structures
Proximity of the molars roots to the floor of the maxillary sinus.
Inferior alveolar canal may approximate the roots of the mandibular molars.






Maxillary molar teeth immediately adjacent to sinus present increased danger of sinus exposure.
Mandibular molar teeth that are close to inferior alveolar canal. Third molar removal is procedure most likely to result in injury to nerve.


• Radiograph of mandibular premolar teeth before extraction should include the mental foramen.






Before premolar extractions are performed, it is essential to know relationship of mental foramen to root apices. Note radiolucent area at apex of second premolar, which represents mental foramen.





Configuration of Roots
Evaluate the following:
• the number of roots

curvature of the roots and the degree

shape of the individual root

size of the root

• evidence of root caries

• root resorption


Evaluate the number of roots. If the number of roots is known before the extraction, an alteration of plan can be made to prevent fracture of additional roots. REFER the patient.







Mandibular canine tooth with two roots. Knowledge of this fact preoperatively may result in less traumatic extraction.

Curvature of the roots and the degree of root divergence. Long roots with severe and abrupt curves or hooks at their apical end are more difficult to remove. REFER the patient.







Widely divergent roots of this maxillary first molar make extraction more difficult.





Hypercementosis increases difficulty of these extractions, because roots are larger at apical end than at cervical end. Surgical extraction will probably be required.

Evidence of caries extending into the roots. Root caries may substantially weaken the root and make it more liable to fracture when the force of the forceps is applied.






Root caries in first premolar tooth make extraction more difficult, because fracture of tooth is likely. Note hyper- cementosis of second premolar.

Root Resorption – either internal or external should be assessed. It weakens the root structure and renders it more likely to fracture. REFER the patient.






Internal resorption of root makes closed extraction almost impossible because fracture of root will almost surely occur.

RCT – there may be ankylosis or the tooth root may be more brittle. REFER the patient.







Tooth made brittle by previous endodontics therapy. It is thus more difficult to remove.

Condition of Surrounding Bone
Evaluate the density of the bone surrounding the tooth to be extracted.
Radiolucent bone is less dense which makes the extraction easier.

Radiopaque bone (indicating increased density) will be more difficult to extract.

Bruxism
• Examine the surrounding bone for evidence of apical pathology.


• Teeth with non-vital pulps may have periapical radiolucencies that represent granulomas or cysts

– beware of such lesions, because they should be removed at the time of surgery.


Bone Exostosis – teeth associated with mandibular tori, palatal tori, and exostosis are difficult to remove.













PROCEDURE FOR DENTAL SURGERY Uncomplicated Extraction Procedure Tray Set-Up

Routinely, this would consist of:


• mirror and explorer

• cotton pliers

• appropriate and sufficient local anaesthetic

• Q-tips and topical anaesthetic

• syringe with long or short needles

• needle guard

• surgical suction tip and saliva ejector

• sufficient gauze sponges

• appropriate forceps and elevators

• bite block






Typical basic extraction tray.
Should the need arise, the following should be at hand:
Curette

• Rongeurs and Bone File

• Cryer Elevators

Light
It is important to have good light on the surgical field. You can't remove what you can't see.

ELEVATORS


Principles of Use
1. An elevator applies force between the root and the surrounding bone of the jaw.
2. Elevators act like wedges with one side of the wedge applying the force of the tooth at the point of application while the other side of the wedge applies an equal and opposite force to the adjacent bone, the fulcrum.
3. To be efficient, the elevator tip needs to be of suitable size. A thick wedge will not gain access to a thin space, and if too wide, the tip will merely jam at the first rotatory movement. A tip that is too narrow will rotate round and round in a large space without engaging root or bone and thus achieves nothing.


(a) Wide elevator in a small space – the direction of displacement is too horizontal and the root is jammed against the bone. (b) Narrow elevator in a large space – nothing is achieved. (c) Correct sized elevator exerting coronal displacing force.


4. Choice of the correct sized elevator will enable the displacement of a root without excessive lateral force.


5. Elevators can also be used to facilitate extraction with forceps by:
• breaking down the periodontal attachment

• allowing access to the forceps at a more apical level



• expanding the bony socket
Safe Use of Elevators
1. The fulcrum for elevation should always be on bone. It is permissible for an adjacent tooth to be used as a fulcrum if that tooth is also to be extracted at the same session. Failure to observe this rule may result in damage to, or even inadvertent extraction of an adjacent tooth.
2. Elevators, like forceps blades, need to be guided carefully but positively into the periodontal space around the root.
3. The tip of an elevator can gain access to almost any point around the circumference of the root.
4. The butt of the handle should be in the heel of the hand to provide force parallel to the long axis of the instrument.
5. The index finger is extended down the shaft towards the tip to control the direction of placement and to act as a safety stop should the elevator slip.
6. The thumb and remaining fingers grasp the handle and provide the rotational component of force. It is the rotation movement that allows controlled force to be applied to the tooth root.
7. The straight elevators come in three standard widths of tip denoted 1, 2, and 3 with 1 being the narrowest. Generally it is advisable to select the smallest size that is effective, and progress to wider ones as the root becomes loosened.
8. Cryer’s elevators have a sharp pointed tip. This allows the tip to be advanced trough thin alveolar bone with modest hand pressure. The angled point is slightly less than right angles to the shaft.

NOTE: These instruments have maximum effect when the angled tip is at 90 degrees to the long axis of the tooth rather than when the shaft is parallel to it.






Coupland’s ‘elevator’ – how to hold it safely and effectively.


Indications for Use of Elevators
1. To free or reflect the gingival cuff.
2. To loosen teeth before their removal with forceps. Failure to use an elevator to reflect the epithelial attachment of the gingival cuff can result in tearing a large piece of gingiva from the bone when the tooth is removed. Teeth that are not loosened before the application of forceps frequently break.
3. To luxate and remove teeth, parts thereof, or structures which cannot be gripped with forceps.
a) Malposed Teeth (teeth out of position) – These teeth may be located in such a position that it is impossible to apply forceps without touching adjacent teeth, or lever a tooth without creating pressure on adjacent teeth. Malposed teeth are usually crowded teeth, for example, bicuspids or third molars which are squeezed lingually, buccally or labially.
b) Tilted Teeth – Teeth may be tilted anteriorly, because of the early loss of adjacent teeth, and therefore it may be impossible to place the beaks of the forceps parallel with the long axis of the tooth.
c) Extensively Decayed Teeth – The crown will probably fracture under pressure of the beaks of the forceps.
4. To remove fractured or carious roots.
5. To split partially sectioned teeth with an air rotor.
6. To remove interseptal bone – cryer elevator


Dangers in the Use of Elevators
Elevators should be used with caution because of the dangers of:
1. Damaging or extracting adjacent teeth.
2. Fracturing the maxilla or mandible.
3. Fracturing the alveolar process.
4. Slipping and plunging the point of the instrument into the soft tissue with possible damage to larger blood vessels and nerves.
5. Penetrating or forcing a root into the maxillary sinus. REFER.
6. Forcing a root of a lower molar into the mandibular canal, or through the lingual plate of the mandible. REFER.

Elevation = Mobilize = Luxation

(to loosen a tooth)

42 ORAL SURGERY

between root and alveolar bone = PDL

space


Never use adjacent tooth as a fulcrum unless it is to be removed as well.




Rules When Using Elevators
1. Do not use an adjacent tooth as a fulcrum (leverage point) unless that tooth is to be extracted as well.
2. Do not use the buccal or lingual plate at the gingival line as a fulcrum. Never.
3. Always use your finger as a guard to protect the patient in case the elevator slips.
4. Be certain that the forces applied by the elevator are under control.
5. Be certain that the elevator tip is exerting pressure in the correct direction, which is apically

(towards the root end) between the tooth and the alveolar bone.


6. Do not elevate from the palatal or the lingual side unless extreme care is used because there are vessels and nerves that could be damaged if the elevator slipped.

Elevation Mechanical Principles
The removal of teeth from the alveolar process employs the use of the following mechanical principles and simple machines:
• lever

• wedge


• wheel and axle


Lever
Elevators are used as levers. A lever is a mechanism for transmitting a modest force – with the mechanical advantage of a long lever arm (shank) and a short effector (blade) – into a small movement against great resistance. Obtain a purchase point so that tooth/root can be mobilized (luxate). Force the blade between root and alveolar bone (PDL space) to obtain purchase point.




Wedge
Wedge principle can be used to expand, split, and displace portions of substance that receives it. The blades of elevators and the beaks of forceps are narrow at their tips and broaden as they go superiorly. When a straight elevator is forced into the PDL space it displaces the root out of the socket.









Wedge can be used to expand, split, and displace portions of substance that receives it.





Beaks of forceps act as wedge to expand alveolar bone and displace tooth in occlusal direction.

Small, straight elevator, used as wedge to displace tooth root from its socket. Its use in this fashion gives this elevator the nickname shoehorn.




Wheel and Axle
The wheel and axle elevator is closely identified with the triangular, or pennant-shaped elevator (Cryer). When one root of a multiple-rooted tooth is left in the alveolar process, the Cryer is inserted into the socket and turned. The handle serves as the axle. The triangular tip acts as a wheel, and engages and elevates the tooth root from the socket.





Triangular elevator in role of wheel-and- axle machine, used to retrieve root from socket.

SUMMARY Dental Elevators
Indications Potential Damage to: Prevention of Damage
1. To reflect gingival cuff Soft tissue of adjacent teeth In all cases, use gentle pressure with well directed and controlled force



2. To luxate (loosen) and remove teeth

Adjacent teeth and structures Do not use adjacent teeth as a fulcrum





3. To luxate (loosen) and remove roots

Soft tissue and adjacent structures (bone or teeth)

Direct forces apically and against bone interproximally



4. To remove interseptal bone Penetration of maxillary sinus, mandibular canal, or lingual plate

Don’t use buccal or lingual alveolar plates as fulcrum nor heavy leverage. Keep pressure mainly apical.


Use good finger rests; always keep control; don’t elevate on palate; use gentle, controlled force.




Always use diagnostic quality radiographs.

If you are not sure if the surgical procedure is within the capability of a dental therapist – REFER the patient to a dentist or oral surgeon.

PRINCIPLES OF SURGERY


Tissue Handling
Tissue is easily damaged by excessive pulling or crushing, extremes of temperature, desiccation, and use of unphysiologic chemicals. When bone is cut, copious amounts of irrigation should be used to decrease the amount of bone damage from heat. Soft tissues should also be protected from frictional heat or direct trauma from drilling equipment (HSHP).


Hemostasis
Prevention of excessive blood loss during surgery is important for preserving the patient’s oxygen carrying capacity. Other important reasons are uncontrolled bleeding causes decreased visibility and formation of hematomas. Hematomas place pressure on wounds, decreasing vascularity, increase tension on the wound edges, and act as a culture media, increasing the chances of wound infection.


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