[Show abstract][Hide abstract] ABSTRACT: This study examined the three-dimensional (3D) changes in craniofacial morphology between 482 identified Portuguese skulls from the eighteenth to the twentieth centuries and 150 modern Portuguese individuals randomly selected from the armed forces. The goal was to investigate the interrelationship between changes in various parts of the skull, in particular, the cranial base, the brain supporting structures, and the face. Cone beam computed tomography images from the identified skull collections belonging to the Department of Life Sciences at the University of Coimbra and Natural History National Museum of Lisbon were used. These 3D images from craniometric analyses included 19 different linear, angular, and orthogonal 3D measurements. The trend in horizontal position of the maxilla (SNA) and horizontal position of the mandible (SNB) angles showed a significant increase, while the relative position of the maxilla to mandible (ANB) and the global angle mean values decreased over time. Skulls from each subsequent century demonstrated a decrease in anterior cranial base, indicated by the mean distance between S and N landmarks. Significant negative correlations were found between SNA and anterior cranial base length (S-N). The negative correlations between SNB and anterior cranial base length (S-N) decreased from the eighteenth to nineteenth centuries. The twenty-first century skulls were characterized by a significant difference in the mean value of different craniofacial variables between males and females. The results of this study suggest changes in the 3D cephalometric measurements of craniofacial architecture. These changes are highly integrated, and show an interesting correlation between structures of the craniofacial facial complex and the anterior cranial base.
international journal of stomatology & occlusion medicine 06/2014; 7(2):33-45. DOI:10.1007/s12548-014-0105-3
[Show abstract][Hide abstract] ABSTRACT: Abstrakt Chronische Erkrankungen der Wirbelsäule, Kopf-schmerzen, Migräne, Kiefergelenkbeschädigungen, -verletzungen, -schmerzen oder -geräusche, Tinnitus, Trigeminusneuralgien oder sogar nicht erklärbare pul-pitische Zahnbeschwerden. Patienten und Ärzte/Zahn-ärzte sind mit diesen Symptomkomplexen vertraut und fürchten sie. Sehr häufig spielt auch eine zahnärztlich-funktionelle Komponente eine wesentliche Rolle bei diesen Krank-heitsbildern, da nicht selten ein enger Zusammenhang mit der statischen oder dynamischen Okklusion be-steht. Ärzte sehen sich hochkomplexen pathologischen Zusammenhängen gegenüber, die häufig ein interdis-ziplinäres Vorgehen verlangen. Aber wer kann helfen? Welche Fachdisziplinen müssen wann und wie zusam-mengeführt und koordiniert werden? Insbesondere soll sich dieser Artikel dem Thema wid-men, wie sich die skelettale Konfiguration des Schädels des Patienten und dessen Okklusion -im Speziellen die vorhandene dreidimensionale Lage der Okklusi-onsebene im Schädel, auf Belastungsverhältnisse und damit Beschädigungs-und Verletzungsmöglichkeiten im Kiefergelenk (TMJ) verhält. Schlüsselworte Okklusion, Temporomandibuläres Gelenk (TMJ), Inter-disziplinäre Medizin/Zahnmedizin Einleitung
[Show abstract][Hide abstract] ABSTRACT: Purpose
Conventional articulators allow the user to adjust the inclination of the incisal table according to reconstruction principles. This fact suggests the adoption of an incisal table which exploits an appropriate curvature related to the individual incisal concavity by the reciprocal motion of the incisors. The aim of this study was to compare different incisal tables by a kinematic analysis of the protrusion motion.
Materials and methods
A parametric planar multibody model of the articulator (reference SL Gamma Dental) was developed by means of the implementation of the contact equations in the sagittal plane both for the condylar and incisal pin/tables guides. Through the use of the parametric model, the equations of contact and motion were mathematically shown for the different devices used in the present study.
Sequenzial incisal tables, individual anterior guidance unit and adjustable curvature were used for the comparison. All the tests were made using three shapes of condylar guidance (CI) with different sagittal condylar inclination (SCI). The numerical parameters of tables were processed and compared to the trajectory of the upper shape of the standard incisal by a mean deviation factor (MDF).
The value of the MDF decreased from a mean value of 0.13 when a flat table was used to a mean value of 0.08 when an adjustable curvature device was used. In all cases the curvature was higher in the first part of the protrusion and progressively decreased during the protrusion path. The variation of the eminence angle may affect the inclination of the ideal incisal table but the curvature is imperceptibly affected by this parameter.
The comparison between three incisal tables showed a better matching of the adjustable curvature of anterior guidance showing full agreement with the results.
international journal of stomatology & occlusion medicine 12/2012; 5(4). DOI:10.1007/s12548-012-0057-4
[Show abstract][Hide abstract] ABSTRACT: Introduction
The position and inclination of the long axis of teeth in the human dentition can be described by a set of rules. The purpose of this study was to analyze the architecture of the mandibular dentition of adult Caucasians using virtual three-dimensional (3D) reconstruction of skulls and mandibles.
In this study 40 skulls from the Weissbach collection at the Vienna Natural History Museum were scanned using cone beam computed tomography. Several angular and linear measurements obtained from the reconstructed images were analyzed.
The inclination of second premolars and first molars was nearest to vertical and mesial inclination became progressively greater for molars. The angular relationship between the tooth long axis and the closing axis of lower incisors ranged from 95 to 98°, while the tooth axis of buccal teeth with the contralateral condyle sequentially increased from canines to third molars. The architecture of occlusion showed that the Bonwill triangle was equilateral with a length of approximately 100 mm (about 4 inches) on one side, the Balkwill angle was approximately 25° and there was a distance of approximately 38 mm between the condyle and occlusal plane (DPO). The angle of the condylar axis inclined to correlate to the 3D structure of the mandible.
This study defines the 3D architecture of occlusion including tooth axis, condyle and shape of the mandible. The results make it possible to consider new aspects of the biomechanics of 3D reconstruction of occlusion.
international journal of stomatology & occlusion medicine 09/2012; 5(3). DOI:10.1007/s12548-012-0053-8
[Show abstract][Hide abstract] ABSTRACT: The hypothesis that the temporal bones are at the center of the dynamics of the craniofacial complex, directly influencing facial morphology, has been put forward long ago. This study examines the role of the spatial positioning of temporal bones (frontal and sagittal inclination) in terms of influencing overall facial morphology. Several 3D linear, angular and orthogonal measurements obtained through computerized analysis of virtual models of 163 modern human skulls reconstructed from cone-beam computed tomography images were analyzed and correlated. Additionally, the sample was divided into two subgroups based on the median value of temporal bone sagittal inclination [anterior rotation group (n = 82); posterior rotation group (n = 81)], and differences between groups evaluated. Correlation coefficients showed that sagittal inclination of the temporal bone was significantly (P < 0.01) related to midline flexion, transversal width and anterior-posterior length of the basicranium, to the anterior-posterior positioning of the mandible and maxilla, and posterior midfacial height. Frontal inclination of the temporal bone was significantly related (P < 0.01) to basicranium anterior-posterior and transversal dimensions, and to posterior midfacial height. In comparison with the posterior rotation group, the anterior rotation group presented a less flexed and anterior-posteriorly longer cranial base, a narrower skull, porion and the articular eminence located more superiorly and posteriorly, a shorter posterior midfacial height, the palatal plane rotated clockwise, a more retrognathic maxilla and mandible, and the upper posterior occlusal plane more inclined and posteriorly located. The results suggest that differences in craniofacial morphology are highly integrated with differences in the positional relationship of the temporal bones. The sagittal inclination of the temporal bone seems to have a greater impact on the 3D morphology of the craniofacial complex than frontal inclination.
Journal of Anatomy 03/2012; 220(6):544-54. DOI:10.1111/j.1469-7580.2012.01499.x · 2.10 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BackgroundThe articular eminence of the glenoid fossa together with the occlusal guiding surfaces represent two fundamental determinants
of mandibular movement and even though subject to numerous investigations the relationship between both structures still remains
unclear today. The purpose of this 3D investigation was to characterize the inclinations of the articular eminence, measure
the inclinations of maxillary occlusal guiding surfaces, investigate the occlusal scheme present and examine the relationship
between anterior and posterior guidance.
MethodsSeveral three-dimensional measurements obtained through computerized analysis of virtual models of 163 human skulls reconstructed
from cone-beam computed tomography (CBCT) images were analyzed and correlated.
ResultsThe inclinations of the articular eminence and of the occlusal guiding surfaces revealed large individual variation. Second
molars showed the lowest inclination values with a significant number of first and second molars presenting buccally inclined
guiding elements. Anterior guidance showed slightly higher inclination values than posterior guidance. Significant correlations
were found between the inclination of the articular eminence and the posterior passive centric line of occlusion.
ConclusionsThe occlusal scheme of sequential guidance with front canine dominance was confirmed. Inferring a direct etiologic anatomical
interrelationship between anterior and posterior guidance may be an oversimplification of the craniomandibular system.
KeywordsDental occlusion, centric–Odontometry–Cross-sectional study–Humans–Cone-beam computed tomography
international journal of stomatology & occlusion medicine 08/2011; 4(1):10-19. DOI:10.1007/s12548-011-0001-z
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 01/2011; 139(1):10, 12, 14 passim. DOI:10.1016/j.ajodo.2010.11.011 · 1.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: The mandibular fossa (MF) connects the mandible to the cranium through a bilateral articulation. It is suggested
that the mandible and the temporal bones have a reciprocal effect on their position and movement, acting as a temporo-mandibular
unit. The purpose of this study was to analyze the possible role of the mandibular fossa in the development of malocclusion
by comparing its three-dimensional (3D) position in different dentoskeletal frames in caucasic European human skulls. METHOD:
Several 3D angular and linear measurements obtained from Cone Beam Computerized Tomography scanning images of 101 skulls from
the Weisbach collection at the Vienna Natural History Museum were analyzed. RESULTS: The position of MF varied in different
dentoskeletal frames. The sagittal position measured from the Nasion or Sella landmark was significantly smaller in Class
III compared with the other two groups. The vertical position of MF did not differ significantly amongst groups. Two effective
ways of evaluating the MF sagittal position are to measure the 3D distance from MF mean landmark to the fronto-nasal suture
(Nasion) or to the Sella landmark. CONCLUSION: The MF position is suggested to be considered an important factor in the development
of malocclusions. Its influence on the position of the mandible supports the idea of a temporo-mandibular unit. Analysis of
the position of MF should be included in the diagnostic process.
KeywordsMandibular fossa-Glenoid fossa-Temporal bone-Cranial base-Mandible-Skull-Human-3DCT-Craniofacial-Vertical dimension
international journal of stomatology & occlusion medicine 12/2010; 2(4):179-190. DOI:10.1007/s12548-009-0031-y
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: The craniofacial architecture is the result of a very complex interrelation. The nasal septum and specially
vomer bone, because of its strategic spatial location between the cranial base and the mid-face, influence the growth of this
area of the facial skeleton, thus playing a major role in the organization of the craniofacial architecture. The purpose was
to analyze the influence of vomer bone on the morphology of the craniofacial architecture, evaluate its correlation with different
structures, and compare the spatial position and dimensions between dentoskeletal frames. METHOD: 3D cephalometric measurements
were analyzed and correlated in 302 digitally reconstructed skulls by 3D CBCT of a caucasic European adult population. RESULTS:
Changes in the inclination and the dimensions of vomer bone were strongly correlated with other craniofacial structures. There
were significant variations in vomer bone between the different dentoskeletal frames. CONCLUSIONS: Vomer bone seems to play
an important role in the interrelation of the craniofacial architecture.
KeywordsVomer-Cranial base-Maxilla-Occlusal plane-Posterior occlusal plane-Skull-3D CBCT
international journal of stomatology & occlusion medicine 12/2010; 2(4):191-204. DOI:10.1007/s12548-009-0032-x
[Show abstract][Hide abstract] ABSTRACT: During individual human ontogenesis, toward the end of their maturation process, erupting teeth stabilize a distinct distance
between the jaws which we call the vertical dimension of the face. The principles that underlie the individuality of vertical
dimension are debated contentiously in all disciplines of dentistry. Cephalometric analyses are used to measure and identify
the VD in diagnosis and treatment planning. In this paper, a standardized database is used to find possible skeletal references
to help establish more individualized standards for lower facial height (after Ricketts) to assist in clinical decisions.
KeywordsVertical dimension-Height of the bite-Lower facial height-Skeletal location
international journal of stomatology & occlusion medicine 12/2010; 3(3):159-164. DOI:10.1007/s12548-010-0060-6
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: The relationship of cranial base angle (CBA) and its influence on the craniofacial morphology remains unclear.
The articular mobility of the cranium because of sutures and synchondroses suggests that the individual behavior of cranial
base during ontogenic development determines the variable position and relation of the craniofacial structures. The purpose
of this study was to analyze the correlation between cranial base angle and the morphology of different craniofacial structures
in three-dimensionally reconstructed skulls of a European caucasic adult population. METHOD: Several three-dimensional angular
and linear measurements obtained from cone beam computerized tomography scanning images of 302 skulls from the Weisbach collection
at the Vienna Natural History Museum were analyzed and correlated. RESULTS: Significant correlations were found between CBA
and different craniofacial structures including positive correlations with the inclination and spatial rotation of vomer bone,
the inclination of the maxilla, and posterior occlusal plane. The vertical dimension of the total and the lower facial height
showed a negative correlation; similar negative results were observed with occlusal plane height to Sella-Nasion plane, and
the sagittal facial dimensions. CONCLUSION: The CBA shows an interesting interrelation with other structures on the three-dimensional
morphology of craniofacial architecture.
KeywordsCranial base-Vomer-Maxilla-Occlusal plane-Posterior occlusal plane-Skull-Human-3DCT-Craniofacial-Vertical dimension
international journal of stomatology & occlusion medicine 12/2010; 2(4):205-215. DOI:10.1007/s12548-009-0033-9
[Show abstract][Hide abstract] ABSTRACT: Despite the numerous investigations addressing the relationship between the inclinations of the dentition’s guiding surfaces and the functional parameters of the TMJ still today this relationship remains imperfectly understood. In an attempt to throw some light on this issue a 3D CBCT study was carried out. Several 3D angular measurements of 163 skulls were obtained and analyzed. The purpose of this investigation were 1) to measure three-dimensionally the inclinations of the temporal articular fossa, specifically the areas of articulation within the fossa; 2) to measure three-dimensionally the inclinations of the guiding surfaces of maxillary teeth, from the central incisors to the second molars; 3) to investigate the occlusal scheme present; and 4) to investigate the relationship between articular tooth surfaces and the articular planes of the glenoide fossa.
International Conference on Interdisciplinary Medicine and Occlusion, Vienna, Austria; 07/2010
[Show abstract][Hide abstract] ABSTRACT: The present study examined possible advantages of a kinematical determination of hinge axis points over arbitrary axis points
in the fabrication of occlusal splints for CMD treatment. The single blinded prospective randomised trial was performed in
a general dental practice. A total of 14 consecutive patients presenting for CMD treatment were considered for participation
and declared informed consent, and 12 patients (average age about 40 years) eventually participated. These patients were randomly
assigned to either fabrication method and were not informed about how their individual splint was constructed. Condylography,
required for the kinematical hinge axis determination, was therefore performed in both groups. Patients were recalled after
1, 2, 4, 14 and 28 days, and splints were selectively ground in order to achieve full occlusal contact in 12 points. The required
number of corrective grindings was recorded, as was the clinical course of the patients. Kinematical splint construction yielded
the desired result – mandibular repositioning as reflected by the full number of occlusal contact points – faster and more
completely than the employment of an arbitrary hinge axis, and substantially (about 50%) less corrective grinding was required.
The difference was statistically significant despite the rather small sample size. Clinically, both methods appeared to be
equally effective. The greater initial effort required by kinematical determination of the individual hinge axis seems to
be at least partially outweighed by a lower amount of corrective grinding required achieving the desired splint effect. Which
method has the superior cost-benefit ratio remains to be determined.
international journal of stomatology & occlusion medicine 09/2009; 2(3):99-105. DOI:10.1007/s12548-009-0021-0
[Show abstract][Hide abstract] ABSTRACT: Neurologische Komplikationen nach der chirurgischen Entfernung eines intrakraniellen Meningeoms im linken Sinus cavernosus
werden in diesem Fallbericht demonstriert. Die Darstellung betrifft eine gesunde, jetzt 27 jährige Frau, welche eine linksseitige
Gesichtsmuskelatrophie in Kombination mit Dysästhesie und Hypalgesie entwickelt hatte. Es werden die diagnostischen und therapeutischen
Schritte im Detail dargestellt. Adäquate und funktionell orientierte diagnostische Verfahren sind Voraussetzung für die Erstellung
eines individuellen Behandlungsplanes. Interdisziplinäre Zusammenarbeit ist gefordert, und zwar mit der klaren gemeinsamen
Zielsetzung der Wiederherstellung der Funktionen des stomatognathen Systems. Muskuläre und neuronale Funktion sind Zielparameter
der Therapie. Zusätzlich ist die in solchen dramatischen Situationen oft angeschlagene psychische Situation der Patienten
zu berücksichtigen. Daher hat als zusätzliches Therapieziel der zahnärztlich funktionellen Maßnahmen auch die Verbesserung
der psychischen Stabilität der Patientin zu gelten. Ein kapitulierendes und resignierendes Therapiekonzept ist nach dem Eintritt
neurologischer Komplikationen, wie in diesem Fall beschrieben, nicht zielführend und sollte daher vermieden werden. Vielmehr
ist ein aktives und vorausblickendes Behandlungskonzept notwendig, basierend auf den individuellen Befunden des betroffenen
A case of neurological complication after surgical procedure for a Meningioma of the left cavernous sinus is presented in
this paper. It concerns a healthy 27 year old woman who developed left side facial muscle atrophy in combination with dysesthesia
and hypalgesia in the left face. The diagnostic and therapeutical approach is described in details. Adequate and functional
orientated diagnostic procedures are mandatory to establish an individual treatment plan. An interdisciplinary treatment,
clearly focused on the recovery of the functions of the stomatognathic system, restores functions and improves local muscular
and neuronal properties. In addition, the stricken psychic situation of the affected patient can be considerable improved
by this approach. A route of capitulation should not be applied in such situations. An active and pre-visional treatment concept
has to be implemented, although the actions taken have to be arranged on an individual base.
[Show abstract][Hide abstract] ABSTRACT: Basic studies and researches on craniofacial growth show that occlusal plane changes its position in space and time during
the whole period of development and growth of the skull until the attainment of the mature dentition stage. The purpose of
this retrospective study is to evaluate the inclination of the gnatological occlusal plane related to the axio-orbital plane
and their relations with skeletal pattern in a group of subjects during the period of mixed dentition stage. This is performed
analyzing cephalometric tracings of 714 untreated children between 5.6 and 12 years old. Observations of data indicate that
there is difference in inclination between skeletal class I, class II and class III, being more steep in class II and more
flat in class III. Variations between the "subclasses" demonstrate very high degree of "individuality" of the inclination
of the occlusal plane related to the functional axio-orbital plane in subjects in mixed dentition stage.
international journal of stomatology & occlusion medicine 02/2009; 2(1):32-35. DOI:10.1007/s12548-009-0005-0
[Show abstract][Hide abstract] ABSTRACT: A case of neurological complication after surgical procedure for a Meningeoma of the left cavernous sinus is presented. It
concerns a healthy 27-year-old woman who developed left side facial muscle atrophy in combination with dysesthesia and hypalgesia
in the left face. The diagnostic and therapeutical approach is described in detail. Adequate and functionally orientated diagnostic
procedures are mandatory to establish an individual treatment plan. An interdisciplinary treatment, clearly focused on the
recovery of the functions of the stomatognathic system, restores functions and improves local muscular and neuronal properties.
In addition, the stricken psychic situation of the affected patient can be considerably improved by this approach. A route
of capitulation should not be applied in such situations. An active and pre-visional treatment concept has to be implemented,
although the actions taken have to be arranged on an individual base.
international journal of stomatology & occlusion medicine 02/2009; 2(1):36-44. DOI:10.1007/s12548-009-0006-z
[Show abstract][Hide abstract] ABSTRACT: The occlusal plane (OP) is one of the most important elements involved in occlusal reconstruction in restorative, prosthodontic
and orthodontic treatment. The presence or absence of posterior interferences depends primarily on the occlusal plane configuration.
In powerful grinding movements of the mandible like bruxism, disocclusion of the posterior teeth is important to prevent the
hyperbalance of masticatory muscle activity. We have investigated the relationship between the inclination of the occlusal
plane involving the degree of the curve of Spee and the posterior disocclusion during forward or retrusive condylar movement.
Results indicated that increasing the inclination of the occlusal plane provides posterior interference during protrusive
mandibular movement, while posterior disocclusion is obtained during retrusive movement. Accentuation of the curve of Spee
provides elimination of posterior contact during retrusive condylar movements. Therefore, the occlusal plane inclination should
be properly and carefully analyzed and must be a part of the diagnosis and treatment planning prior to any occlusal reconstruction.
international journal of stomatology & occlusion medicine 11/2008; 1(1):27-33. DOI:10.1007/s12548-008-0007-3