Objectives: It is critical to determine the location and configuration of the
mandibular canal and related vital structures during the implant treatment. The
purpose of the present study was to review the literature concerning the
mandibular canal and inferior alveolar neurovascular bundle anatomical
variations related to the implant surgery.
Material and Methods: Literature was selected through the search of PubMed, Embase and
Cochrane electronic databases. The keywords used for search were mandibular
canal, inferior alveolar nerve, and inferior alveolar neurovascular bundle. The
search was restricted to English language articles, published from 1973 to
November 2009. Additionally, a manual search in the major anatomy, dental
implant, prosthetic and periodontal journals and books were performed.
Results: In total, 46 literature sources were obtained and morphological aspects
and variations of the anatomy related to implant treatment in posterior mandible
were presented as two entities: intraosseous mandibular canal and associated
inferior alveolar neurovascular bundle.
Conclusions: A review of morphological aspects and variations of the anatomy related
to mandibular canal and mandibular vital structures are very important
especially in implant therapy since inferior alveolar neurovascular bundle
exists in different locations and possesses many variations. Individual, gender,
age, race, assessing technique used and degree of edentulous alveolar bone
atrophy largely influence these variations. It suggests that osteotomies in
implant dentistry should not be developed in the posterior mandible until the
position of the mandibular canal is established.
Anatomy of Mandibular Vital Structures. Part II: Mandibular
Incisive Canal, Mental Foramen and Associated Neurovascular
Bundles in Relation with Dental Implantology
Gintaras Juodzbalys, Hom-Lay Wang, Gintautas Sabalys
Objectives: The purpose of the present study was to review the literature of how to
identify the mental foramen, mandibular incisive canal and associated
neurovascular bundles during implant surgery and how to detect and avoid the
damage of these vital structures during implant therapy.
Material and Methods: Literature was selected through a search of PubMed, Embase and Cochrane
electronic databases. The keywords used for search were mandibular incisive
canal, mental foramen, mental nerve, anterior mental loop. The search was
restricted to English language articles, published from 1979 to November 2009.
Additionally, a manual search in the major anatomy, dental implant, and
periodontal journals and books was performed.
Results: In total, 47 literature sources were obtained and reviewed. The
morphology and variations of the mandibular incisive canal, mental foramen and
associated neurovascular bundles were presented as two entities. It
suggested that clinicians should carefully assess these vital structures to
avoid nerve/artery damage.
Conclusions: The mandibular incisive canal, mental foramen and associated
neurovascular bundles exist in different locations and possess many variations.
Individual, gender, age, race, assessing technique used and degree of edentulous
alveolar bone atrophy largely influence these variations. It suggests that the
clinicians should carefully identify these anatomical landmarks, by analyzing
all influencing factors, prior to their implant surgical operation.
Objectives: Peptide-15 (P-15) is an analogue of the cell binding domain of collagen.
P-15 has been shown to facilitate physiological to process in a way
similar to collagen, to serve as anchorage for cells, and to promote the
binding, migration and differentiation of cells. However, how P-15
alters osteoblast activity to promote bone formation is poorly
understood. To study the osteoinductive properties of peptide P-15, we
analyzed the expression levels of bone related genes in human
mesenchymal stem cells treated with this biomaterial.
Material and Methods: Using real time Reverse Transcription-Polymerase Chain Reaction the
quantitative expression of specific genes, like transcriptional factors (RUNX2
and SP7), bone related genes (SPP1, COL1A1, COL3A1, BGLAP, ALPL, and FOSL1) and
mesenchymal stem cells marker (ENG) were examined.
Results: P-15 causes a considerable induction of osteoblast transcriptional
factor like osterix (SP7) and of the bone related genes osteopontin
(SPP1) and osteocalcin (BGLAP). In contrast the expression of endoglin
(ENG) was markedly decreased in stem cells treated with P-15 respect to
untreated cells, indicating the differentiation effect of this
biomaterial on stem cells.
Conclusions: The present study shows the effect of P-15 on mesenchymal stem cells in
the early differentiation stages: P-15 is an inducer of osteogenesis on
human stem cells as indicated by the activation of bone related markers
SP7, SPP1 and BGLAP.
The results may allow a better understanding of the molecular mechanism
of bone regeneration and as a model for comparing other materials with
similar clinical effects.
The Influence of Tube Potential on Periodontal Bone Level
Measurements and Subjective Image Quality Using a Digital
Photostimulable Storage Phosphor Sensor
Objectives: The purpose of the present study was to determine
the measurement accuracy and subjective image quality for periodontal
disease diagnosis when using two X-ray tube voltages with a digital
photostimulable storage phosphor sensor.
Material and Methods: A digital photostimulable storage phosphor (PSP) sensor (Vistascan) and
a multipulse X-ray generator (Prostyle Intra) with two tube voltages were used
in this study. The front, premolar and molar region of two adult human cadaver
skulls jaws were imaged using the X-ray tube at 63 kV and 70 kV, both at 8 mA
and decreasing exposure times (160 ms, 120 ms and 80 ms). A standardized
exposure protocol containing waxed occlusal keys and an aiming device ensured
proper and reproducible beam alignment. Three observers assessed the digital
radiographs for 31 selected periodontal bone loss sites. Radiographic
measurements were compared to physical measurements (Standard). Subjective
ratings of lamina dura, crater defect and furcation involvement visibility,
contrast perception and bone quality were also performed.
Results: Multiple regression equation of the variables kV and exposure time
demonstrated no significant difference for the periodontal bone level
measurements (P > 0.05). In 90.3% and 96.7% of the measurements for 70 kV and 63
kV respectively, deviation was within 1 mm. The subjective ratings produced
similar findings in terms of image quality for both tube voltages and the three
exposure times.
Conclusions: The results of the present study revealed that tube voltages of 63 kV
and 70 kV provided similar accuracy and image quality for periodontal disease
diagnosis.
Reliability of Periapical Radiographs and
Orthopantomograms in Detection of Tooth Root Protrusion in the
Maxillary Sinus: Correlation Results with Cone Beam Computed
Tomography
Objectives: The purpose of the present study was to investigate the reliability of
both periapical radiographs and orthopantomograms for exact detection of
tooth root protrusion in the maxillary sinus by correlating the results
with cone beam computed tomography.
Material and Methods: A database of 1400 patients scanned with cone beam computed tomography
(CBCT) was searched for matching periapical (PA) radiographs and orthopantogram
(OPG) images of maxillary premolars and molars. Matching OPG images datasets of
101 patients with 628 teeth and PA radiographs datasets of 93 patients with 359
teeth were identified. Four observers assessed the relationship between the apex
of tooth root and the maxillary sinus per tooth on PA radiographs, OPG and CBCT
images using the following classification: root tip is in the sinus (class 1),
root tip is against the sinus wall (class 2) and root tip is not in the sinus
(class 3).
Results: Overall correlation between OPG and CBCT images scores was 50%, 26% and
56.1% for class 1, class 2 and class 3, respectively (Cohen’s kappa [weighted] =
0.1). Overall correlation between PA radiographs and CBCT images was 75.8%,
15.8% and 56.9% for class 1, class 2 and class 3, respectively (Cohen’s kappa
[weighted] = 0.24). In both the OPG images and the PA radiographs datasets,
class 1 correlation was most frequently observed with the first and second
molars.
Conclusions: The results demonstrated that both periapical radiographs and
orthopantomograms are not reliable in determination of exact relationship
between the apex of tooth root and the maxillary sinus floor. Periapical
radiography is slightly more reliable than orthopantomography in determining
this relationship.
Objectives: The purpose of the present study was to explore the maxillary sinus
anatomy, its variations and volume in patients with a need for maxillary implant
placement.
Material and Methods: Maxillary sinus data of 101 consecutive patients who underwent spiral
computed tomography (CT) scans for preoperative implant planning in the maxilla
at the Department of Periodontology, University Hospital, Catholic University of Leuven, Leuven,
Belgium were retrospectively evaluated. The alveolar bone height was measured on
serial cross-sectional images between alveolar crest and sinus floor, parallel
to the tooth axis. In order to describe the size of the maxillary sinus
anteroposterior (AP) and mediolateral (ML) diameters of the sinus were measured.
Results: The results indicated that the alveolar bone height was significantly
higher in the premolar regions in comparison to the molar region (n = 46, P <
0.01). The age showed negative relation to bone dimension (r = - 0.32, P =
0.04).
Anterior and posterior border of the maxillary sinuses were mostly
located in the first premolar (49%) and second molar (84%) regions,
respectively. Maxillary sinus septa were indentified in 47% of the
maxillary antra. Almost 2/3 (66%) of the patients showed major (> 4 mm)
mucosal thickening mostly at the level of the sinus floor. The present
sample did not allow revealing any significant difference (P > 0.05) in
maxillary sinus dimensions for partially dentate and edentulous
subjects.
Conclusions: Cross-sectional imaging can be used in order to obtain more accurate
information on the morphology, variation, and the amount of maxillary bone
adjacent to the maxillary sinus.
Background: The hard and soft tissue deficiency is a limiting factor for the
prosthetic restoration and any surgical attempt to correct the anatomic
foundation needs to be precisely executed for optimal results. The purpose of
this paper is to describe the clinical steps that are needed to confirm the
treatment plan and allow its proper execution.
Methods: Team work and basic principles are emphasized in a step-by-step
description of clinical methods and techniques. This clinical report
describes the interdisciplinary approach in the rehabilitation of a
partially edentulous patient. The importance of the transitional
restoration which sets the guidelines for the proper execution of
the treatment plan is especially emphasized along with all the steps
that have to be followed.
Results: The clinical report describes the diagnostic arrangement of teeth, the
ridge augmentation based on the diagnostic evaluation of the removable
prosthesis, the implant placement with a surgical guide in the form of
the removable partial denture duplicate and finally the special 2-piece
design of the final fixed prosthesis.
Conclusions: Clinical approach and prosthesis design described above offers a
predictable way to restore partial edentulism with a fixed yet
retrievable prosthesis, restoring soft tissue and teeth and avoiding an
implant supported overdenture.
Background: This current clinical case report highlights three cases of Hereditary
angioedema (HAE) patients who are all members of the same family (father and his
two daughters). The father has C1–INH deficiency, while his daughters have low
C1–INH levels: the first possesses only 10% function and the second has low
C1–INH level with 0% function. Of note, the second daughter was discovered to
have HAE at the age of 2, thus making her the youngest known HAE case report in
the English literature.
Methods: Assess the efficacy of administration of C1-INH before dental operation
as regards the prevention of HAE episode, when total or partial C1-INH
deficiency exists.
Results: Acute angioedema leading to laryngeal oedema is a possibly fatal
complication for HAE patients undergoing dental procedures. Use of both
short-term and long-term HAE prophylaxis prior to dental operations might be
life saving for those patients.
Conclusions: Prevention and early recognition of potential laryngeal oedema that can
occur as a complication of dental procedures may be lifesaving for HAE patients.