1、外科牙齿拔除术外科牙齿拔除术Extraction is a surgery The extraction of teeth,however accomplished,is a surgical operation involving bony and soft tissues of the oral cavity,access to which is restricted by the lips and cheeks,and further complicated by the movement of the tongue and mandible.2外科牙齿拔除术3外科牙齿拔除术 It is
2、 essential that this phase of oral surgery be given the same careful study and application of sound surgical principles as is given to surgery in any other part of the human body.4外科牙齿拔除术Indications for the extraction of teeth The following are indications for the extraction of teeth.(a)teeth that a
3、re foci of infections;(b)teeth with nonvital pulps,or acute or chronic pulpitis when root canal therapy is not indicated;5外科牙齿拔除术 6外科牙齿拔除术 (c)in cases of severe periodontoclasia in which excessive bony support of the teeth is destroyed;7外科牙齿拔除术Indications for the extraction of teeth(d)teeth not trea
4、table by apicoectomy;(e)teeth mechanically interfering with the placement of restorative appliances;(f)teeth not restorable by operative dentistry;8外科牙齿拔除术 (g)impacted teeth;(h)supernumerary teeth;(i)retained deciduous teeth when a succedaneous tooth is present,and in normal position to erupt;9外科牙齿拔
5、除术Indications for the extraction of teeth(j)teeth with fractured crown;(k)malposed teeth not amenable to orthodontic treatment;(l)roots;(m)teeth that are traumatizing soft tissues,if other treatment will not prevent this trauma.10外科牙齿拔除术Contraindications:systemic diseases 11.Uncontrolled diabetes me
6、llitus 1.Uncontrolled diabetes mellitus 2.Cardiac disease,such as coronary artery disease.2.Cardiac disease,such as coronary artery disease.hypertension,and cardiac decompensation,e.g.hypertension,and cardiac decompensation,e.g.postinfarction within 6 months postinfarction within 6 months3.Blood dys
7、crasias such as anemias,hemorrhagic diseases e.g.3.Blood dyscrasias such as anemias,hemorrhagic diseases e.g.hemophilia,and the leukemias.hemophilia,and the leukemias.4.Debilitating diseases of any kind making patients poor risks 4.Debilitating diseases of any kind making patients poor risks for fur
8、ther traumatic insults.for further traumatic insults.5.Addisons disease or any steroid deficiency,such as the 5.Addisons disease or any steroid deficiency,such as the patient who has been treated for any disease with steroid patient who has been treated for any disease with steroid therapy may not h
9、ave sufficient adrenal cortex secretion therapy may not have sufficient adrenal cortex secretion to withstand the stress of an extraction without taking to withstand the stress of an extraction without taking additional steroids.additional steroids.11外科牙齿拔除术Contraindications:systemic diseases 26.Fev
10、er of unexplained origin is rarely cured and often is 6.Fever of unexplained origin is rarely cured and often is worsened by extraction,e.g.subacute bacterial worsened by extraction,e.g.subacute bacterial endocarditis would be complicated considerably by an endocarditis would be complicated consider
11、ably by an extraction.extraction.7.Nephritis7.Nephritis8.Pregnancy:extraction is better to be done in the second 8.Pregnancy:extraction is better to be done in the second trimester.Menstruation:elective exodontia is not done trimester.Menstruation:elective exodontia is not done during the period bec
12、ause of less nervous stability and during the period because of less nervous stability and greater tendency toward hemorrhage of all tissues.greater tendency toward hemorrhage of all tissues.9.Senility:greater care in overcoming a poor physiologic 9.Senility:greater care in overcoming a poor physiol
13、ogic response to surgery and a prolonged negative nitrogen response to surgery and a prolonged negative nitrogen balance.balance.10.Psychoses and neuroses10.Psychoses and neuroses12外科牙齿拔除术Local contraindications 1.Acute infection with an uncontrolled cellulitis,toxemia until adequate blood level of
14、a specific antibiotic had brought systemic factors under control and the infection had become localized,the pus was drained,and the infection had subsided to a chronic state.2.Acute pericoronitis 3.Acute infectious stomatitis 4.Malignant disease 5.Irradiated jaws may develop an acute radio-osteomyel
15、itis after extraction13外科牙齿拔除术special instruments for the extraction The special instruments for the extraction of teeth and roots are forceps,elevators.In special cases,where bone has to be removed,other instruments required such as chisels and mallet,burs,etc.14外科牙齿拔除术 A very large variety of forc
16、eps and elevators have been devised.A few well-selected instruments will suffice all hut very extraordinary cases.15外科牙齿拔除术Straight elevatorPhysical characteristics 1.Large,bulbous handle.2.Working end resembles a sharp,narrow,elongated spoon.3.Straight shank,parallel to the working end.Use 1.To sep
17、arate and loosen the tooth in its alveolus.2.To remove large tooth fragments.Application Positioned between the tooth and its alveolus.16外科牙齿拔除术Maxillary posterior forcepsUniversal maxillary forceps Physical characteristics 1.Plierslike appearance.Beaks have smooth edges that allow them to fit aroun
18、d the bifurcated areas of all maxillary molar teeth.a point on the buccal beak that allows them to fit into the buccal bifurcation area.Use To extract maxillary posterior teeth from their alveoli.17外科牙齿拔除术Maxillary premolar forceps/universal forceps Physical characteristics 1.Plierslike appearance.2
19、.Instruments with bayonet-shaped beaks are Universal.Use To remove premolar teeth from their alveoli in the maxillary arch.18外科牙齿拔除术Mandibular posterior forceps Physical characteristics 1.Plierslike appearance.2.Universal design and therefore functional in either quadrant of the arch.3.Often referre
20、d to as a cowhorn forceps.Use To remove mandibular posterior teeth from their alveoli sockets.19外科牙齿拔除术Mandibular incisor and premolar extraction forcepsPhysical characteristics l.Plierslike appearance.2.Beaks designed to remove all mandibular teeth,but most often used on incisors and premolars.UseT
21、o extract mandibular incisor and premolar teeth.Pedodontic extraction forceps Physical characteristics 1.Design identical to forceps manufactured for use on permanent teeth.2.Smaller in size than standard forceps.UseTo remove primary teeth from the oral cavity.20外科牙齿拔除术Bone chisel/surgical Mallet Ph
22、ysical characteristics Chisel 1.Length and width of the shaft vary.2.Cutting end available in single-bevel and double-bevel designs.Mallet 1.Hammer shaped.2.Head available in lead or nylon.Use To trim or reshape bone to section teeth.21外科牙齿拔除术INSTRUMENT STERILIZATION A profession engaged in deliveri
23、ng health care must be concerned with infection.It is imperative that sterilization of dental instruments be a routine procedure in every dental office.Various methods of disinfection and sterilization can be employed to reduce the probability of infection and crosscontamination.It is mandatory that
24、 the dental team understand and properly use these methods.22外科牙齿拔除术Sterilization Sterilization is the act of destroying all forms of life.The most accepted methods in dentistry and medicine for achieving true sterilization are extended periods of high heat and steam heat.23外科牙齿拔除术Disinfection Disin
25、fection only inhibits the growth of disease-causing microorganisms and is not nearly as effective as sterilization.Only dental instruments that cannot withstand the high temperature of heat sterilization should be placed in a disinfectant solution.Some of the chemicals available for use as disinfect
26、ants are benzalkonium chloride,hexachlorophene,and rubbing alcohol.A more popular term for chemical disinfection is cold sterilization.”The instruments are placed in an open disinfectant bath for the required length of time.24外科牙齿拔除术IMPACTED TEETH A tooth is spoken of as being impacted when its erup
27、tion is partially or wholly obstructed by bone or some other teeth.25外科牙齿拔除术Impacted TeethClassification of Mandibular Impacted Teeth The classification of mandibular impacted teeth may be stated simply as(l)mesioangular,(2)horizontal,(3)vertical,and(4)distoangular.In addition,the tooth may be displ
28、aced to the buccal or to the lingual.Furthermore it may be located at a high occlusal level(near the ridge surface)or a low occlusal level.26外科牙齿拔除术27外科牙齿拔除术Etiology Many pathologic conditions bring about retarded eruption,displacement and impaction of teeth.The growth of the jaws and the movement o
29、f the teeth are in a forward direction;consequently,anything which interferes with this forward movement or growth will cause impaction of the teeth.Acute infectious fevers of childhood,such as scarlet fever and measles,may interfere with the forward movement by producing a deposit of dense bone.28外
30、科牙齿拔除术Etiology Local increase in the density of the bone may also be brought about by inflammation of the peridental membrane,extending into the alveolar process.Severe traumatism to the jaws may cause a deposit of lime salts in the cancellated bone tissue and thus bring about impaction.Ankylosis of
31、 the mandibular joint in childhood,resulting in arrest of growth of the jaws,may leave insufficient space for the eruption of all teeth.Too early extraction of deciduous teeth may cause arrested development of the jaws and malpositions of the permanent teeth,this leading in turn to impaction of uner
32、upted teeth.29外科牙齿拔除术Disturbances caused by impacted teeth Impacted teeth may be present without giving rise to any symptoms whatever.Others cause many complications such as some of local and general effects.30外科牙齿拔除术(I)Local effects An impacted third molar may press against the crown of the second
33、molar and cause decay of the tooth,or itself becomes the seat of caries around the point of contact.It may also cause pressure absorption of the root of the second molar.Exposure and devitalization of the pulp from these causes may give rise to neuralgia.Neuralgia may be caused in another way by pre
34、ssure of the impacted tooth on the inferior dental nerve or its branches.31外科牙齿拔除术(I)Local effects-cont.Sometimes,especially in the case of the lower third molar,pericoronal infection,pericoronal abscess,cellulitis and osteomyelitis are set up,often accompanied by trismus.In any patient suffering fr
35、om acute cellulitis in the back part of the mouth and inability to open the mouth,an impacted lower third molar should be suspected.32外科牙齿拔除术(Il)General effects Impacted teeth may be the cause of obscure headaches.Cases of more serious nervous or even mental disturbance have been at times traced to
36、this cause.In such conditions as epilepsy,chorea and dementia precox,impacted teeth may at least be a contributing factor.In these cases there may be no local signs of trouble.33外科牙齿拔除术Treatment If treatment is indicated,it consists as a general rule in removal by operation of the impacted tooth35外科
37、牙齿拔除术Principle of Removal of Mandibular Impacted Teeth The underlying principle in the removal of mandibular impacted teeth is a sectioning technique.Bone is removed to expose the crown.The tooth is split with a fresh sharp chisel so that a good portion of the crown is separated from the tooth.When
38、this portion is removed,space is obtained so that the remainder of the tooth can be elevated into the defect.Before this technique was developed,space for elevation was obtained by more extensive bone removal and consequently more trauma.36外科牙齿拔除术37外科牙齿拔除术Complications of extraction of teeth(1)Loose
39、ning of adjacent teeth is caused by inappropriate use of forceps and elevators.(2)Fracture of adjacent teeth and restorations occasionally occurs during a routine extraction procedure.This most commonly occurs with the inappropriate use of elevators.Teeth can be fractured if the tooth being extracte
40、d suddenly yields to uncontrolled force and the forceps strike the opposing teeth.38外科牙齿拔除术Complications(3)Fracture of the buccal or labial plate may occur.The surgeon who frequently fractures the buccal or labial plate must analyse his techniques,since this is considered heavy handed surgery in the
41、 light of more appropriate refined techniques.(4)Teeth or roots into the maxillary sinus is possible either during forceps extraction or root retrieval.It is quite easy to displace roots of upper molar teeth into the maxillary sinus.39外科牙齿拔除术Injury to the inferior alveolar nerve(5)Injury to the infe
42、rior alveolar nerve may occur when the inferior alveolar nerve is closely associated with roots and sometimes with the crown of the mandibular third molar.Operations in this region can easily damage the nerve.Perhaps the easiest way of damaging the nerve is during sectioning of a horizontally impact
43、ed third molar lying directly above the mandibular canal.This complication can be prevented by surgeons precaution and refined techniques.40外科牙齿拔除术Postoperative hemorrhages leading causes(6)Postoperative hemorrhages leading causes are:patients manipulation of the wound.foreign body in the socket,suc
44、h as bone or tooth fragments.sharp bone margins and fractured socket walls.excessive granulation tissue not removed at time of surgery.hypertension.clotting deficiency or vascular disorder.41外科牙齿拔除术Postoperative pain (7)Postoperative pain which the patient experiences after the second and third post
45、operative days should be carefully examined,since this is not a normal postoperative course.It is caused by dry socket or sharp bone spine.42外科牙齿拔除术Dry sockets clinical appearance (8)Dry sockets clinical appearance is well known.Two or three days after removal of the tooth,the blood clot disintegrat
46、es.The alveolus is empty,with completely or partially denuded,very sensitive blanc surfaces,covered by a grey-yellow layer of detritus and necrotic tissue.The surrounding gingiva often shows an inflammatory reaction.43外科牙齿拔除术Symptoms of dry socket The patient complains of violent pain,usually throbb
47、ing in character,which radiates toward the ear and temporal region.The patient complains of a bad taste in the mouth,swelling of the regional lymph nodes is common.General symptoms,such as increased temperature,are seldom seen but the patient may be psychically affected because of the severe pain,an
48、d feel unwell due to lack of sleep and appetite.44外科牙齿拔除术Local treatment of dry socket Local treatment consists of repeated irrigations with warm normal saline solution,application of analgesics and antibiotic ointment in the wound.General use of analgesic agent is needed.45外科牙齿拔除术Postexodontic Comp
49、lications:Dry socket(localized osteitis)Etiology:the following factors increase the incidence of this painful post-extraction sequela:trauma,infection,decreased vascular supply of the surrounding bone,and general systemic condition.Clinically the condition may be described as an alveolus in which th
50、e primary blood clot has become necrotic and remains within the alveolus as a septic foreign body until it is removed by irrigation.46外科牙齿拔除术Ecchymosis (9)Ecchymosis generally is seen following flap procedures and is found most often in elder patients,especially women,who have decreased capillary re
