Implants - Applied anatomy and physiology for dental implants                                 

HOME           Implant Home  

Basic overview of anatomy with special consideration for structures directly related to implant placement

• Surgical and Radiographic Anatomy for Oral Implantology. Al-Faraje, 1^st edition 2013. Quintessence Pub.

• Sharawy and Misch. Applied Anatomy for Dental Implants (CH 22). pp 490-501. Contemporary Implant Dentistry, Misch, C.E., 3rd Edition, 2008, Mosby Year Book.

• Netter’s Head and Neck Anatomy for Dentistry. Norton. 2007. Saunders.

1. Neiva RF, Gapski R, et al. Morphometric analysis of implant related anatomy in Caucasian skulls. J Periodontol 2004; 75(8): 1061-1067

2. Du Tolt DF, Nortje C. The maxillae: integrated and applied anatomy relevant to dentistry. SADJ 2003; 58(8):325-330.

3. Quirynen M, Mraiwa N, et al. Morphology and dimensions of the mandibular jaw bone in the interforaminal region in patients requiring implants in the distal areas. Clin Oral Implants Res. 2003 Jun;14(3):280-5.

4. Kalpidis CD, Setayesh RM. Hemorrhaging associated with endosseous implant placement in the anterior mandible: a review of the literature. J Periodontol. 2004 May;75(5):631-45

5. Mardinger O et al: Lingual perimandibular vessels associated with life – threatening bleeding. An anatomic study. Int J Oral Maxillofac Implants 2007; 22:127-131

6. Chrcanovic BR, Abreu MH, Custódio AL. A morphometric analysis of supraorbital and infraorbital foramina relative to surgical landmarks. Surg Radiol Anat. 2011 May;33(4):329-35.

7. Chrcanovic BR, Custódio AL. Anatomical variation in the position of the greater palatine foramen. J Oral Sci. 2010 Mar;52(1):109-13.

8. Reiser GM, Bruno JF, Mahan PE, Larkin LH. The subepithelial connective tissue graft palatal donor site: anatomic considerations for surgeons. Int J Perio Rest Dent. 1996 Apr;16(2):130-7.

Topic: Anatomy                            implant related anatomy in skulls

Authors: Neiva RF, Gapski R, et al.

Title: Morphometric analysis of implant related anatomy in Caucasian skulls.

Source: . J Periodontol 2004; 75(8): 1061-1067

Type: Morphometric analysis study

Rating: Good

Keywords: Dental implantation, dental implants, foramen, mental, grafts, bone, jaw anatomy, histology, maxillary sinus augmentation, mandibular symphysis.

BACKGROUND: Sequelae related to implant placement/advanced bone grafting procedures are a result of injury to surrounding anatomic structures. Damage may not necessarily lead to implant failure; however, it is the most common cause of legal action against the practitioner.

PURPOSE: To evaluate the anatomy most commonly associated with implants dentistry and advanced bone grafting procedures, such as symphysis onlay grafts and sinus lifts, and to provide dimensional measurements that could aid the clinician in overall implant treatment planning.

METHODS:

• Morphometric analyses were performed in 22 Caucasian skulls.

• Measurements of the mental foramen (MF) included height (MF-H), width (MF-W), and location in relation to other known anatomical landmarks.

• Presence or absence of anterior loops (AL) of the inferior alveolar nerve (IAN) was determined, and the mesial extent of the loop was measured.

• Additional measurements included height (G-H), width (G-W), thickness (G-T), and volume (G-V) of monocortical onlay grafts harvested from the mandibular symphysis area, and thickness of the lateral wall (T-LW) of the maxillary sinus.

• The independent samples t test, and a two-tailed t test with equal variance were utilized to determine statistical significance to a level of P < 0.05. Multiple regression analyses were performed to determine if each one of these measurements was affected by age and gender.

RESULTS:

• The most common location of the MF in relation to teeth was found to be below the apices of mandibular premolars.

  • The mean MF-H was 3.47 +/- 0.71 mm

  • The mean MF-W was 3.59 +/- 0.8 mm

• The mean distance from the MF to other anatomical landmarks were:

  • MF-CEJ = 15.52 +/- 2.37 mm

  • MF to the most apical portion of the lower cortex of the mandible = 12.0 +/- 1.67 mm

  • MF to the midline = 27.61+/- 2.29 mm

  • MF-MF = 55.23 +/- 5.34 mm.

• A high prevalence of AL was found (88%); symmetric occurrence was a common finding (76.2%), with a mean length of 4.13 +/- 2.04 mm.

• The mean size of symphyseal grafts was:

  • G-H = 9.45 +/- 1.08 mm

  • G-W = 14.5 +/- 3.0 mm

  • G-T = 6.15 +/- 1.04 mm, with an average G-V of 857.55 +/- 283.97 mm3 (range: 352 to 1,200 mm3).

• The mean Thickness-Lateral wall of the maxillary sinus was 0.91 +/- 0.43 mm.

CONCLUSION: Implant-related anatomy must be carefully evaluated before treatment due to considerable variations among individuals, in order to prevent injury to surrounding anatomical structures and possible damage.

_____________________________________________________________________

Topic: Anatomy                    applied anatomy

Authors: Du Tolt DF, Nortje C

Tittle: The maxillae: integrated and applied anatomy relevant to dentistry.

Source: SADJ 2003; 58(8):325-330.

Type: Discussion article

Rating: Good

Keywords: maxillae, anatomy, sinus, nerves

Purpose: To address applied anatomy of the maxilla relevant to the practice of dentistry and maxilla-facial surgery.

Discussion:

• The first pharyngeal arch develops to form a cranial maxillary and caudal mandibular process.

• The maxilla presents a body and 4 processes: the frontal, zygomatic, alveolar and palatine processes.

• The ostium drains into the hiatus semilunaris of the middle nasal meatus.

• The infraorbital foramen transmits the infraorbital nerve and vessels. A block to this nerve anesthetizes: Sup labial, nasal and inferior palpebral branches of the infraorbital n. Ant sup alveolar N and Middle sup alv nerve (usually). Teeth: Central, lateral, canine and possible 1^st and 2^nd premolars. The adjacent plate of the labial alveolar bone, vestibular gingiva, alv mucosa, upper lip, lateral aspects of the nose, lower lid skin and conjuctiva together with the anterior aspects of the maxillary sinus are anesthetized.

• The posterior or infratemporal fossa forms the anterior wall of the infratemporal fossa. Visible are the apertures of the 2-3 alveolar canals, that transmit the PSA vessels.

• The superior surface of the maxilla contributes to the formation of the floor of the orbit.

• The palatine process of the maxilla forms the greater part of the floor of the nasal cavity and roof of the mouth.

• The incisive fossa transmits terminal branch of the greater palatine A, and nasopalatine nerve.

• Terminal branches of maxillary artery relevant to the maxilla: PSA, descending palatine A, Infraorbital A, Shenopalatine A, Greater palatine A, Lesser palatine A, Ant sup alv A.

• In some patients orofacial infections may be life threatening, if the abscess or cellulitis spread from one region to another.

• Ludwig’s angina is not a maxillary disease, but arises from a massive infection of the submandibular and sublingual regions.

• Maxillary sinus

1. Pyraminal shape.

2. Lateral wall: infratemporal wall of the maxilla

3. Medial wall: Inferior part of the lateral wall of the nasal cavity

4. Roof: Floor of the orbit

5. Floor: narrow bony plate over premolars and molars.

6. Most often sinuses are of equal and symmetrical size.

________________________________________________________________________

Topic: Interforaminal bone morphology

Authors: Quirynen M, Mraiwa N, van Steenberghe D, Jacobs R

Title: Morphology and dimensions of the mandibular jaw bone in the interforaminal region in patients requiring implants in the distal areas.

Source: Clin Oral Implants Res. 2003 Jun;14(3):280-5.

Type: Clinical study

Rating: Good

Keywords: bone grafting, bone morphology, implant surgery, radiographic evaluation, surgical complications, surgical planning

Purpose: To analyze variations in the mandibular interforaminal morphology in an attempt to identify potential risks or contraindications for surgery, especially implant installation, in this particular region.

Methods: 210 CTs of patients requiring endosseous implants in the lower jaw were re-evaluated to investigate anatomical variations in bone morphology (shape and contour), and to measure parameters concerning height, width, and inclination of the bone. All measurements were performed on the cross-sectional reformatted images mesial to the mental foramina.

Results: Three arbitrary morphologies were created: Type I: with a lingual concavity, Type II: A lingual concavity with a nearly constant width, but a clear lingual slope and Type III: with bone widening in the caudal direction. A lingual concavity (depth 6 ± 2.6 mm) was observed in 2.4% of the jaws with remaining bone height in that area ranging from 4.2 to 11.9 mm. Type II morphology was seen 28.1% of the time and type III 69.5% of the time. A clear lingual tilt/inclined morphology was seen in 28.1% of jaws with a mean angle of 67.6 ± 6.5°, but a relatively constant width (> 8.8 mm). The remaining jaws (69.5%) showed a slight broadening in the caudal direction. Morphology was not affected by age or gender.

Conclusion: Mandibles with a lingual concavity or a severe slope of the lingual cortex might have increased risks of lingual perforations during implant placement. ________________________________________________________________________

Topic: Anatomy                Hemorrhaging

Authors: Kalpidis CD, Setayesh RM.

Title: Hemorrhaging associated with endosseous implant placement in the anterior mandible: a review of the literature

Source: J Periodontol. 2004 May;75(5):631-45

Type: Review

Rating: Good

Keywords: Airway obstruction/prevention and control, dental implantation/adverse effects, dental implantation/complications, dental implants/adverse effects, dental implants/complications, emergency care, foramen/anatomy, mouth floor/blood supply, oral hemorrhage/prevention and control

Purpose: 1) To review all available published case reports recording massive bleeding incidents following implant positioning in the anterior segments of the mandible. 2) To bring to the attention of the clinical community this extremely rare but serious and potentially fatal complication. 3) To present a brief but concise regional arterial anatomy and a description of the important anatomical structures related to this life-threatening complication. 4) To provide guidelines for avoiding severe bleeding events and for immediate management should an emergent situation develop during or after surgical implantation.

Discussion: The placement of endosseous dental implants is largely considered a safe surgical procedure. However, upper airway obstruction secondary to severe bleeding in the floor of the mouth has been occasionally reported as a rare but potentially fatal complication of implant surgery. This review presents critical hemorrhagic episodes, related to dental implantation in the anterior segments of the mandible, published to date. Massive internal bleeding in the highly vascularized region of the floor of the mouth is the result of an arterial trauma induced by instrumentation, usually through a perforation of the lingual cortical plate. Depending on the clinical situation, hemorrhage may commence immediately or with some delay after the vascular insult. The progressively expanding lingual, sublingual, submandibular, and submental hematomas have the tendency of displacing the tongue and floor of the mouth to obstruct the airway. Because the course of airway deterioration to complete occlusion may be rapid, ensuring a patent airway is of highest priority. Even though upper airway obstruction is potentially life-threatening, a secure airway was successfully established in all patients without fatal consequences. In most cases, resolution of hemorrhage required a surgical intervention for ligation of the bleeding vessels and hematoma evacuation. To reduce the probability of such a grave complication, preventive and precautionary measures to be taken before, during, and after implant placement in the anterior mandible are presented. Issues related to the level of surgical experience, fine regional arterial anatomy, radiographic and clinical evaluation of the osseous morphology, angulation and length of implants, and timing of hemorrhage onset are discussed. In addition, airway and bleeding management strategies are provided.

Topic: Implant complications

Title: Lingual perimandibular vessels associated with life – threatening bleeding. An anatomic study

Author: Mardinger O et al

Source: Int J Oral Maxillofac Implants 2007; 22:127-131

Type: Discussion

Rating: Good

Keywords: emergency, lingual perforation, implants, floor of mouth hemorrhage

Purpose: To describe the anatomy of the lingual perimandibular vessels and emphasize their distance to the bone.

Methods: 12 human cadavers were dissected. Blood vessels in the floor of the mouth were exposed using sagittal incisions at the canine, mental foramen, and second molar region.

Results: The diameter of the dissected vessels ranged from 0.5 to 3 mm (mean 1.5 mm). Most vessels were found superior to the Mylohyoid muscle in the canine area and inferior to the muscle in the mental and second molar areas. The smallest median vertical distance from blood vessel to bone was in the canine area (14.5 mm), followed by the mental foramen area (15.5 mm) and the second premolar area (19 mm). The median horizontal distance of the  vessels from the lingual plate was 2 mm at the canine and second molar areas and 4 mm at the mental area.

Discussion: Lingual plate perforation, especially anterior to the canine area, can easily injure blood vessels in the floor of the mouth and cause life-threatening hemorrhage following implant placement. Bleeding can occur when the mandibular lingual plate is perforated. Care should be taken to recognize situations where this complication may occur.

Conclusion: Based on the study of human cadavers, it appears that vessels in the floor of the mouth are sometimes in close proximity to the site of implant placement. Caution should be exercised when placing implants in this area.

________________________________________________________________________

Topic: Applied anatomy and physiology for dental implants           foramina

Authors: Chrcanovic BR, Abreu MH, Custódio AL. 

Title: A morphometric analysis of supraorbital and infraorbital foramina relative to surgical landmarks.

Source: Surg Radiol Anat. 2011 May;33(4):329-35.

Type: Review

Rating: Good

Keywords: supraorbital and infraorbital foramina, human dry skulls

Purpose:

To examine the different morphometric variations of the supraorbital and infraorbital foramina of the facial skeleton on human skulls.

Methods:

Eighty adult human dry skulls were studied. Measurements were made to analyze the degree of variability in the location of the supraorbital and infraorbital foramina. All measurements were done bilaterally. Variations were evaluated according to gender and side

Results:

54 females and 26 males crania. Almost all mean measurements were longer in males than in females. A statistically significant difference was observed between the left and the right sides in 4 of 10 measurements. When comparing the morphometric measurements between left and right sides of male and female crania, 6 of 22 measurements were statistically higher in men than in women.

Conclusion:

Gender should be taken into account when the foramina studied here are to be located. The mean location of the infraorbital nerve was about 6.5 mm inferior to the inferior orbital rim (at the point where one can palpate the zygomatico-maxillary suture), about 25 mm from the midline, and about 43 mm below the supraorbital foramen in the same vertical line. Extra care should be taken during surgical dissection in the superior orbital region especially in the middle aspect of the superior orbital rim. In general, there were changes in measurements between the genders, but the ratios of these measurements with the horizontal and vertical measurements chosen remained the same between the genders.

Topic: Anatomical considerations                    greater palatine foramen

Author: Chrcanovic BR, Custódio AL

Title: Anatomical variation in the position of the greater palatine foramen

Source: J Oral Sci. 2010 Mar;52(1):109-13

Type: Cadaver study

Rating: Good

Keywords: greater palatine foramen; hard palate; skull anatomy; local anesthesia methods

Purpose: To define the position of the greater palatine foramen (GPF) in relation to several anatomical landmarks in the maxilla in Brazilian skulls.

Methods: The study was conducted on 80 dry human skulls. The following measurements and observations were made:

1. Location of the foramen in relation to maxillary molar teeth

2. Perpendicular distance from the medial border of GPF to the midline maxillary suture (MMS)

3. Distance from the posterior wall of GPF to the post border of the hard palate (PBHP)

4. Direction of opening of the foramen onto the palate

5. Distance from ant wall of GPF to post border of incisive foramen

6. Angle between the MSS and line from the incisive foramen and the GPF

7. The palatine length

Results:

Bottom Line: This study presents valuable clinical information in regards to the location of the GPF. In living subjects, the molar teeth, palatal midline and posterior border of the hard palate are all easily identifiable. That using a combination of the above measurements, the location of the GPF can be plotted with accuracy.

________________________________________________________________________

Topic: Anatomy

Authors: Reiser GM, Bruno JF, Mahan PE, Larkin LH

Title: The subepithelial connective tissue graft palatal donor site: anatomic considerations for surgeons

Source: Int J Perio Rest Dent. 1996 Apr;16(2):130-7

Type: Cadaver study

Rating: Good

Keywords: Connective tissue graft, palate, anatomy, palatal vault

Purpose: To describe the anatomy of the palatal donor site and to identify structures that could potentially create surgical complications.

Methods: Incisions were made in palates of cadavers, reproducing the palatal incisions needed to obtain donor tissue. The tissue was then elevated and removed from the site. When the procedure was complete, the palatal tissue covering the donor site was removed and the donor tissue replaced to show the distance between the superior edge of the donor tissue and the palatal neurovascular structures.

Results/Conclusions: Knowledge of the anatomy of the soft tissues, hard palate, and neurovascular structures is mandatory to avoid surgical complications when obtaining donor tissue. The thickest tissue can usually be obtained in the premolar region. If this tissue is not sufficient, the other side of the palate can be harvested simultaneously. High palatal vaults have greater tissue availability compared with low palatal vaults. A thick alveolus or exostosis in the molar region can limit the amount of tissue harvested from this area. In the event of serious bleeding complications, 3 steps are recommended: immediate pressure (constant, 5 minutes at least) and injection of local anesthetic with vasoconstrictor, placement of one or more sutures proximal to the bleeding site, and elevation of full thickness flap so that the vessel can be visualized and ligated.