Mandibular Third Molar

Anatomically unpredictable, the mandibular third molar must be...read more.

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Mandibular First Premolar

Often considered an enigma to the endodontist, the mandibular...read more.

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Roots Magazine 01.2011

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Maxillary Third Molar

Loss of the maxillary first and second molars is often the reason for...read more.

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Mandibular Second Molar

Somewhat smaller coronally than the mandibular first molar....read more.

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Maxillary Canine

The longest tooth in the dental arch, the canine has... read more.

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Maxillary Second Molar

Coronally, the maxillary second molar closely resembles the maxillary first molar, although it is not as... Read more.

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Maxillary Third Molar

Loss of the maxillary first and second molars is often the reason for considering the third molar as a strategic abutment. The other indication for endodontic treatment and full coverage is a fully functioning mandibular third molar. Careful examination of root morphology is important before recommending treatment. Many third molars present adequate root formation; and given reasonable accessibility, there is no reason why they cannot remain as functioning dentition after endodontic therapy. The radicular anatomy of the third molar is completely unpredictable, and it may be advisable to explore the root canal morphology before promising success. As an alternative to conventional hand instrumentation, the use of engine-mounted files in reciprocating handpieces may simplify the problem of accessibility. Precurving instruments helps guide them through tortuous canals. For visual and mechanical convenience the access may be overextended slightly with the knowledge that full coverage is mandatory. All caries, leaking restorations, and pulpal calcifications must be removed prior to instituting treatment. Some third molars will have only a single canal, some two, and most three. The orifice openings may be made in either a triangular arrangement or a nearly straight-line (Burns RC, Buchanan LS. Tooth Morphology and Access Openings. Part One: The Art of Endodontics in Pathway of Pulp, 6th Ed. p. 150.

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Maxillary Second Molar

Coronally, the maxillary second molar closely resembles the maxillary first molar, although it is not as square and massive. Access in both teeth can usually be adequately prepared without disturbing the transverse ridge. The second molar is often easier to prepare because of the straight-line access to the orifices. The distinguishing morphologic feature of the maxillary second molar is its three roots grouped close together, and sometimes fused. The parallel root canals are frequently superimposed radiographically. They are usually shorter than the roots of the first molar and not as curved. The three orifices may form a fiat triangle, sometimes almost a straight line. The floor of the chamber is markedly convex, giving a slightly funnel shape to the canal orifices. Occasionally the canals curve into the chamber at a sharp angle to the floor, making it necessary to remove a lip of dentin so the canal can be entered more in a direct line with the canal axis. Complications in access occur when the molar is tipped in distal version. Initial opening with an end-cutting fissure bur is followed by a short-shanked round bur, which is best suited to uncover the pulp chamber and shape the access cavity. Then small hand instruments are used to establish canal continuity and working length. The bulk of the cleaning and shaping may now be accomplished with engine-mounted files on reciprocating handpieces. To enhance radiographic visibility, especially when there is interference with the malar process, a more perpendicular and distal-angular radiograph may be exposed. All caries, leaking restorations, and pulpal calcifications must be removed prior to initiating endodontic treatment. Full occlusal coverage is mandatory to ensure against vertical cuspal or crown-root fracture. Internal reinforcement, when indicated, should be incorporated immediately after endodontic treatment. (Burns RC, Buchanan LS. Tooth Morphology and Access Openings. Part One: The Art of Endodontics in Pathway of Pulp, 6th Ed. p. 148).

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy

Maxillary First Molar

The tooth largest in volume and most complex in root and root canal anatomy, the "6-year molar" is possibly the most treated, least understood, posterior tooth. It is the posterior tooth with the highest endodontic failure rate and unquestionably one of the most important teeth. Three individual roots of the maxillary first molar provide a tripod: the palatal root, which is the longest, and the distalbuccal and mesial-buccal roots, which are about the same length. The palatal root is often curved buccally in its apical third. Of the three canals, it offers the easiest access and has the largest diameter. Its orifice lies well toward the palatal surface and it is sharply angulatcd away from the midline. Crosssectionally it is flat and ribbonlike, requiring close attention to debridement and instrumentation; fortunately there is rarely more than one apical foramen. The distal-buccal root is conical and usually straight. It invariably has a single canal. The mesial-buccal root of the first molar has generated more research, clinical investigation, and pure frustration than has probably any other root in the mouth. Green9 stated that two foramina were present in 14% of mesial-buccal roots of the maxillary first molars studied and two orifices were noted in 36%. Pineda reported that 42% of these roots manifested two canals and two apical foramina. Slowey supported Pineda's conclusions within a few percentage points. Kulild indicated that a second ML canal was contained in the coronal half of 95.2% of the mesial-buccal roots examined. The canals were located with hand instruments (54.2%), bur (31.3%), and microscope (9.6%). Each tooth was sectioned in 1-mm increments and although not all canals reached the apex, this study revealed that 71.1% had two patent canals at the apex. It is the author's opinion that the spaces located beyond true canals were finlike extensions found commonly in the broad buccolingual root of the maxillary first molar. The fact that almost half of these roots bear two canals, whether they join into a single foramen or not, is enough reason always to assume that two canals exist until careful examination proves otherwise. The extra orifice lies centrally somewhere between the mesial-buccal and palatal orifices. Kulild also reported that the mesial-lingual canal orifice averaged 1.82 mm lingual to the mesial-buccal canal orifice. Searching for the extra orifice is aided by using the fiberoptic light and by locating the developmental line between the mesial-buccal and palatal orifices. The second canal within the mesial-buccal root is always smaller than the other canals and, so, is often more difficult to clean and shape. Gaining access to the primary canal within the mesial-buccal root can be made easier by improving the angle of approach. All caries, leaking restorations, and pulpal calcifications must be removed prior to initiating endodontic treatment. After treatment it is mandatory to institute full coverage to ensure against vertical cuspat or crown-root fracture. It is also advisable to place internal metal reinforcement whenever there is a significant loss of coronal tooth structures. (Burns RC, Buchanan LS. Tooth Morphology and Access Openings. Part One: The Art of Endodontics in Pathway of Pulp, 6th Ed. p. 148).

 

 

Keywords: micro-computed tomography, micro-ct, marco versiani, micro-computer tomography, high resolution x-ray tomography, dental anatomy, root canal anatomy