Endodontology and Endodontics
Endodontics is a branch of dental science concerned with the study of form , function , health of, injuries to and diseases of the dental pulp and periradicular region and their treatment The etiology and diagnosis of dental pain and disease are considered to be integral to endodontic practice .Endodontic treatment is any procedure designed to maintain the health ,or part of the pulp .When the pulp is diseased or injured ,the treatment aim is maintaining or restoring the health of the periradicular tissues ,usually by root canal treatment but occasionally in combination with endodontic surgery .
So what is Endodontic (Root Canal) Treatment? Endodontics is the specialty in dentistry concerned with the prevention, diagnosis, and treatment of diseases or injuries to the dental pulp. The pulp, which some people call "the nerve," is the soft tissue inside the tooth that contains the nerves and blood vessels and is responsible for tooth development. Root canal treatment is a safe and effective means of saving teeth that otherwise would be lost.
What are the alternatives to root canal treatment? The only alternative is to extract the tooth, which often leads to shifting and crowding of surrounding teeth and subsequent loss of chewing efficiency. The patient should understand that often extraction is the easy way out and, depending on the case, may prove to be more costly for the patient in the long run. The patient always reserves the right to do nothing about the problem, provided the dentist has explained the associated risks of this decision.
What Causes the Pulp to Die or Become Diseased?
When a pulp is injured, diseased, and unable to repair itself, it becomes inflamed and eventually dies. The most frequent causes of pulp death are:
3.trauma (e.g., severe blow to a tooth),
4.cracks in teeth.
5.periodontal or gum disease.
When a pulp is exposed to bacteria from decay or saliva that has leaked into the pulp system, infection can occur inside the tooth and, if left untreated, can cause infection to build up at the tip of the root, forming an abscess. Eventually the bone supporting the tooth will be destroyed, and pain and swelling will often accompany the infection. Without endodontic treatment, the tooth will eventually have to be removed.
What Are the Symptoms of a Diseased Pulp?
Symptoms may range from momentary-to-prolonged, mild to severe pain on exposure to hot or cold or on chewing or biting. In some cases the condition may produce no symptoms at all. The patient should be informed that the radiographic examination may or may not demonstrate abnormal conditions of the tooth. The clinician should also make it clear that sometimes in the absence of pain there is radiographic evidence of pulpal or periradicular disease or both.
Single Visit Versus Multi visit Treatment
There has been much debate concerning single visit versus multi visit endodontic treatment. Indications and contraindications exist for either choice. Recent studies have extended our understanding about postoperative pain associated with each approach; they have also extended our understanding of relative success rates.
Indications: A vital case is often a candidate for single visit treatment. The number of roots, time available, and dentist's skills are also factors to be considered. Some studies demonstrate that even with symptoms, a vital case may be treated in a single visit. Of course, anatomic or periodontal complications may modify such a treatment plan. Vital asymptomatic teeth that cannot be well sealed between visits are ideal candidates for single-visit endodontic. For example an anterior tooth fractured at the gingival margin is often treated in a single visit.
Contraindications: Some studies suggest a lower success rate in single-visit, non vital cases with apical periodontitis than with the multi visit approach. It has been postulate that the inter visit use of an antimicrobial dressing is an essential factor in eradicating all infection from the root cana1. so retreatment cases are another group that would benefit from a multi visit approach
Contraindications to single-appointment root canal treatment include the following:
1. Significant pain and/or swelling.
2. Inability to dry the canal.
3. Persistence of purulent drainage in the canal during instrumentation.
Diagnosis: is the procedure, of accepting a patient, recognizing that he has a problem determining the cause of the problem, and developing a treatment plan that will solve the problem.
Requirements of a diagnostician:
1.knowledge: A dentist must depend on himself; therefore, knowledge is the most important asset the dentist, must possess .
2.Interest:The dentist must have a keen interest in the patient and his or her problem and must evidence this interest by handling the patient with understanding.
3.Intuition or "sixth sense": This ability, which sometimes allows for instant diagnosis is developed through broad experience with pain problems having unusual and multiple diagnosis. Intuition tells the dentist when the patient is not telling the complete truth! .
4.Curiosity: Dental diagnosis is like the actions of a good detective, and curiosity is a detective's greatest asset.
5.Patience: if the dentist is not a willing to sacrifice the time to attempt to help these individuals who complain of unusual pain, he is urged to refer the patient for diagnosis rather than make an incorrect quick diagnosis that may result in improper treatment.
6.Senses: The dentist has senses with which he communicates with the sick patients. The mind must list all of the possible causes of the pain and then eliminate them one by one until the correct diagnosis is made.
A complete medical history should contain the vital signs; give early warning of unsuspected general disease; and define risks to the health of the staff as well as identify the risks of treatment to the patient.
Chief Complaint:The chief complaint is a description of the dental problem for which the patient seeks care.
Present Dental Illness: Pain is the main component of the patient's complaint. A history of pain that persists without exacerbation may indicate a problem not of dental origin. If the chief complaint is toothache but the symptoms are too vague to establish a diagnosis , analgesics can be prescribed to help the patient tolerate the pain until the toothache localized.
The initial questions should help establish two basic components of pain: time (chronicity) and severity or intensity. A history of painful responses to thermal changes suggests a problem of pulpal origin and will need to be followed up with clinical tests .
Medical history: In reviewing the medical history, particular emphasis must be placed on illnesses, history of bleeding, and medications. Women should be asked if they are pregnant or if they have any related problems.
The results of the examination; along with the information from the patient's history will establish the diagnosis.
1.Blood Pressure (normal; 120/80 mm Hg for persons under age 60; 140/90 mm/fig for persons overage 60) The use of sphygmomanometer brings to light unsuspected cases of hypertension in some patients. It must be stressed that no patient should be treated when his diastolic blood pressure is over 100 mm.
2.Pulse Rate and Respiration (normal: pulse, 60 to 100 beats/minute; respiration, (16 to 18 breaths per minute). Pulse and respiration, rates may be elevated due to stress and anxiety.
3.Temperature (normal:; body temperature, 37.5ºC (98.6 F). If the body temperature is not elevated it means that the body is managing its defenses well
4.Cancer Screen (soft tissue examination: lumps, white spots). This examination should include the face, lips, neck and intraoral soft tissues
Extra oral examination
Inflammatory changes originating intra orally and observable extra orally may indicate a serious, spreading problem. The extra oral examination includes the face, lips, and neck, which may need to be palpated if the patient reposts soreness or if there are apparent areas of inflammation . Painful and/or enlarged lymph nodes denote the spread of the inflammation as well as possible malignant diseases. The extent and manner of jaw opening can provide information about possible myofacial pain and dysfunction. The lips and cheeks are retracted and the oral vestibules and buccal mucosa are examined for localized swelling and sinus tract or color changes, the dentist should evaluate the lingual and palatal soft tissues. Finally carious lesions, discolorations, and other abnormalities associated with, the teeth, including loss of teeth and presence of supernumerary or retained deciduous teeth should be noted.. Using a mouth mirror and an explorer(probe) the dentist carefully examines the suspected tooth or teeth for caries, defective restorations, discoloration, enamel loss, or defects that allow direct passage of stimuli to the pulp.
Thermal stimuli, percussion, palpation, and vitality tests can evaluate the clinical condition
of the pulp. The purpose of evaluating the pulpal condition is to arrive at a diagnosis-namely.
the nature of the disease involving the pulp. After determining the diagnosis, there are specific
treatment options for each case. Irreversible pulpitis and pulp necrosis require removal of the
pulp (root canal treatment, or extraction of the tooth), whereas a tooth with normal pulp or with
reversible pulpitis may be treated with vital pulp therapy.
No dental examination is complete without careful evaluation of the teeth's periodontal support. There is agreement that a potential interaction exists between the pulp and periodontium. For the purposes of endodontic treatment of a single 'tooth, probing may be limited to the tooth involved and at least the adjacent teeth. As part of a total oral examination, all teeth should be included in the probing evaluation. Gingival and sulcular bleeding and drainage, along with the presence of plaque and calculus, should also be noted.
Clinical endodontic tests
There are several ways to obtain information about the condition of a tooth's pulp and supporting structures. Probably no one test is sufficient in itself; the results of several tests often have to be obtained to have enough information to support the diagnosis.
1.Thermal tests : Two types of thermal tests are available, cold and hot stimuli. The cold test may be used in differentiation between reversible and irreversible pulpitis and in identifying teeth with necrotic pulp . It can also alleviate paln_brought on by hot or warm stimuli; In testing, if the pain lingers, that is taken as evidence for irreversible pulpitis; if pain subsides immediately after stimulus removal, hypersensitivity or reversible pulpitis is the more, likely diagnosis. teeth with calcified canals may have vital pulps but cold stimuli may not be able to excite the nerve endings due to insulating effect of irritation dentin. Cold testing can be with air blast, a cold drink, an ice stick; or ethyl chloride. Hot testing can be made with a stick of heated gutta-percha or hot water. Hot water is preferable because it allows simulation of the clinical situation and also may be more effective in penetrating porcelain-fused-to-metal crowns. The use of a hot stimulus in the form of hot water can help locate a symptomatic tooth with a necrotic or dying pulp. .
2.Percussion:Since apical periodontitis is so frequently associated with pulpal inflammation
percussion tests are included when evaluating pulpal conditions. The procedure for testing is
simple: use a mirror handle and very gently tap the occlusal /incisal surfaces of several teeth in
the area in question.
3.palpation : This test signals the further spread of inflammation from the periodontal ligament to the periosteum overlying the bone.
This examination is most effective when it can. be made bilaterally at the same, time so that information can be obtained about asymmetry and fluctuation in the area examined.
4.Electric pulp Test. The testing procedure must be explained to the patient. An apprehensive or confused, patient may give false responses. Electric pulp testing provides limited, though often very useful, information, whether or not the pulpal nerve fibers are responsive to electric stimulation. Many factors affect the level of response: enamel thickness, probe placement on the tooth, dentin calcification, interfering restorations, and patient's level of anxiety. Moreover, false-positive and false negative results may happen, so electric pulp testing results must be evaluated carefully. A recently erupted tooth may give a negative response . A young tooth traumatized by impact may not respond to testing. Multi rooted teeth often give bizarre pulp test readings when, one canal rn ay have vital pulp tissue and the other canals necrotic tissue.
Electric pulp testing
Dry the teeth and isolate them with cotton rolls. Cover the tip of the electrode with toothpaste. To stimulate the pulp nerve fibers, the electric current must complete a circuit from the electrode through the tooth, through the patient, and back to the electrode. With gloved hands, this connection is interrupted. To establish a complete circuit using rubber gloves, the patient may complete the circuit by placing a finger on the metal electrode handle. This method will give the patient more control: simply lifting the finger off the electrode handle when the, sensation is felt will immediately interrupt the current and terminate the stimulation.
Multi rooted teeth may need to be tested by placing the electrocle on more than one crown location. It has been suggested that using an electric pulp tester on patients who have
cardiac pacemaker is contrainclicated /since it can modify the normal pacemaker function.
5.The laser Doppler Flowmetry: This method has been shown to measure pulpal blood flow
and thus the degree of vitality .
6. Liquid Crystals Testing: Cholesteric liquid crystals have been used to show the difference in tooth temperature between teeth with vital (hotter) pulps and necrotic (cooler) pulps .
7.Occlusal pressure test: Several methods exist such as biting? on an orange wood stick, or wet cotton roll. The orange wood stick allows pinpoint testing of individual cusp areas, whereas the wet cotton roll has the advantage of adapting to the occlusal surface allowing for pressure over the entire occlusal table. This test, is useful in identifying teeth with symptoms of apical periodontitis, abscess ,cracks. An interesting clinical observation in patients with tooth infractions (cracked tooth syndrome) is pain often experienced when biting force is .released rather than during the down ward chewing motion.
8.Anesthetic Test: Pain in the oral cavity is frequently referred from one tooth to an adjacent one or even from, one quadrant to the opposing one. The anesthetic test can help identify the quadrant from where the focus of pain originates. The suspected tooth should be anesthetized and, if the diagnosis is correct, the referred pain should disappear, even when It is referred to the opposing arch.
9. Test Cavity: This test is often a last resort in testing for pulp vitality. It is important to explain the procedure to the patient because it must be done without anesthesia. Make a preparation through the enamel or existing restoration until the dentin is reached. If the pulp is vital, the heat from the bur will probably generate a response from the patient, however, it may not necessarily be an accurate indication of the degree of. the pulpal vitality.
In the consequence of examination, radiographic evaluation should come last .it is very necessary to know the normal structure before interpreting the abnormal .it is also important to identify structures such as the mandibular canal and maxillary sinus and approach them with. caution during endodontic treatment and surgery. Continuous lamina dura is an indication of healthy periodontal tissues. If there is slight inflammation at the apex, the lamina dura is lost as the periodontal ligament space widens.
Radiographic coronal evaluation includes depth of caries and restorations as well as
evidence of pulp capping or pulpotomy, dens evaginatus, and the size of the preparations under porcelain or resin jacket crowns. It was found that lesions were always larger than their radiographic image, especially, in the mandibular molar region. Lesions in the premolar area were slightly larger than their radiographic image. Also it was found that cortical bone had to be damaged by an osseous lesion before radiolucency could be detected and that loss of cancellous bone alone was not enough to be visible radiographically.
Factors influencing prognosis
Periodontal diseases :
Periodontal stability is a basic requirement for any tooth being considered for endodontic therapy. This stability is determined by the amount of bony support, the health of that support, and the health of the overlying soft tissue. Isolated bone loss or tooth mobility may or may not signify periodontal disease. It may be owing to periradicular disease of pulpal origin, or it may be combined periodontal-endodontic disease. Generalized bone loss of periodontal disease will affect prognosis and therefore the treatment plan. Test for mobility; grade 0 means normal mobility, grade 1; slight mobility, grade 2; marked mobility, and grade 3; mobility and depressible. Also record if bleeding occurs on probing.
Prior to any endodontic treatment, and after all present coronal restorations and caries are removed, the remaining tooth structure should be re-examined carefully for fractures and perforations. At this time, teeth with vertical fractures or severe perforation are untreatable.