Wilfried Engelke

Intra-oral compartment pressures: a biofunctional model and experimental measurements under different conditions of posture

Oral posture is considered to have a major influence on the development and reoccurrence of malocclusion. A biofunctional model was tested with the null hypotheses that (1) there are no significant differences between pressures during different oral functions and (2) between pressure measurements in different oral compartments in order to substantiate various postural conditions at rest by intra-oral pressure dynamics. Atmospheric pressure monitoring was simultaneously carried out with a digital manometer in the vestibular inter-occlusal space (IOS) and at the palatal vault (sub-palatal space, SPS). Twenty subjects with normal occlusion were evaluated during the open-mouth condition (OC), gently closed lips (semi-open compartment condition, SC), with closed compartments after the generation of a negative pressure (CCN) and swallowing (SW). Pressure curve characteristics were compared between the different measurement phases (OC, SC, CCN, SW) as well as between the two compartments (IOS, SPS) using analysis of variance and Wilcoxon matched-pairs tests adopting a significance level of α = 0.05. Both null hypotheses were rejected. Average pressures (IOS, SPS) in the experimental phases were 0.0, −0.08 (OC); −0.16, −1.0 (SC); −48.79, −81.86 (CCN); and −29.25, −62.51 (SW) mbar. CCN plateau and peak characteristics significantly differed between the two compartments SPS and IOS. These results indicate the formation of two different intra-oral functional anatomical compartments which provide a deeper understanding of orofacial biofunctions and explain previous observations of negative intra-oral pressures at rest.

The importance of electromagnetic articulography in studying tongue motor function in the framework of an orthodontic diagnosis

Objective data are required for assessing the influence of movements of the tongue on the position of the teeth. Electromagnetic articulography (EMA) makes it possible to track movements of the tongue using the principle of inductive distance measurement. A helmet made of light but robust acrylic material serves as a carrier for three transmitter coils; these latter are located in front of the forehead, in front of the chin, and at the back of the neck. Receiver coils are fixed to the tip of the tongue and at various points on the dorsum of the tongue. The distance between the receiver coils and the transmitter coils is calculated in real time by means of a personal computer. The movement trajectories are displayed on the computer screen in different colors in X-Y coordinates. The movements of the tongue are recorded in patients with correctly positioned front teeth and compared with those in patients with a frontal open bite. The significance of electromagnetic articulography for dental research and functional treatment is demonstrated.ZusammenfassungIn der Kieferorthopädie werden Fehlfunktionen der Zunge als Faktor bei der Entstehung von Dysgnathien diskutiert. Ein neues objektives Verfahren zur Untersuchung motorischer Zungenfunktion ist die elektromagnetische Artikulographie (EMA). Mit ihr können Bewegungen der Zunge dargestellt sowie deren räumliche und zeitliche Koordination beschrieben werden. Das System arbeitet nach dem Prinzip der induktiven Abstandsmessung unter Verwendung alternierender Magnetfelder. Drei Senderspulen sind an einem Kunststoffhelm befestigt. Die Bewegung der Zunge wird gemessen, indem Empfängerspulen auf die Zunge geklebt werden und ihr Abstand zu den Senderspulen berechnet wird. Beispielsweise ist es möglich, einen Meßpunkt an der Zungenspitze und verschiedene Punkte im Bereich des Zungenrückens abzuleiten. Die gewonnenen Daten werden mit Hilfe eines Personal-Computers weiter analysiert. Anhand von Patienten ohne Fehlfunktion und ohne Dysgnathie wird die Zungenbewegung mit Hilfe der elektromagnetischen Artikulographie beim Sprechen und Schlucken aufgezeichnet und graphisch dargestellt. Die gewonnenen Befunde werden zu klinischen und röntgenologischen Befunden in Relation gesetzt. Da einer unphysiologischen Zungenfunktion Bedeutung für die Entwicklung eines frontal offenen Bisses zugeschrieben wird, wird eine entsprechende Untersuchung bei Patienten mit dieser Dysgnathieform durchgeführt. Während bei Patienten ohne Fehlfunktion und ohne Dysgnathie sich ein mehr vertikal gerichtetes Bewegungsmuster der Zunge bei charakteristischen Testlauten und beim Schlucken nachweisen läßt, zeigen sich bei Patienten mit einem frontal offenen Biß zusätzlich zu den vertikalen mehr sagittal gerichtete Komponenten im Bewegungsmuster der Zunge.SummaryObjective data are required for assessing the influence of movements of the tongue on the position of the teeth. Electromagnetic articulography (EMA) makes it possible to track movements of the tongue using the principle of inductive distance measurement. A helmet made of light but robust acrylic material serves as a carrier for three transmitter coils; these latter are located in front of the forehead, in front of the chin, and at the back of the neck. Receiver coils are fixed to the tip of the tongue and at various points on the dorsum of the tongue. The distance between the receiver coils and the transmitter coils is calculated in real time by means of a personal computer. The movement trajectories are displayed on the computer screen in different colors in X-Y coordinates. The movements of the tongue are recorded in patients with correctly positioned front teeth and compared with those in patients with a frontal open bite. The significance of electromagnetic articulography for dental research and functional treatment is demonstrated.

The influence of FDBA and autogenous bone particles on regeneration of calvaria defects in the rabbit: A pilot study

The histological behavior of bone formation using three biomaterials was examined including whether an 8mm rabbit calvarial defect would behave as a critical size defect. Four trephine defects of 8mm diameter in were created six rabbit parietal bones. A control defect was maintained only with coagulum and others were filled with autologous bone, FDBA (freeze dried bone allograft) and a mixture of autologous bone with FDBA, respectively. The animals were sacrificed after between 15 and 90 days at intervals of two weeks and the extracted samples were processed for histological evaluation. All control defects showed incomplete bone formation during 90 days of observation. The defects filled with FDBA and mixture of FDBA-autologous bone exhibited a higher regeneration degree than autologous bone after 60 days; however, the only biomaterial revealing complete mineralization of the original defect at 90 days was FDBA. In conclusion, 8mm defects can be considered as critical size defects and only FDBA showed mature lamellar bone at 90 days.

Endoscopic Visualization of Anatomic Structures as a Support Tool in Oral Surgery and Implantology

d Endoscopy is a procedure that can be used to improve the visualization of surgical sites with difficult access. In the past, various attempts were made to use endoscopes in different fields of oral surgery. Held et al first used ndoscopes as a tool for periradicular surgery. Bahcall nd Barss recommended endoscopic imaging of the oot canal as a possible future technique during nonoprative endodontic treatment. Engelke and Deckwer used maxillary endoscopy to control the preparation of the subantral space for sinus floor augmentation. Ozawa et al and Stambaugh developed flexible endoscopes ith integrated irrigation systems for observation of the eriodontal sulcus. For support-immersion endoscopy, the endoscope is placed inside the anatomic cavities and supported at any part of the cavity wall under continuous irrigation; thus, a clear visualization of intraosseous structures is provided. Using support endoscopy, the size of a lateral approach for sinus floor augmentation was reduced with the development of the subantroscopic laterobasal technique without limitation of the augmentation volume. Compared with the result of conventional procedures, the hardand soft-tissue mobilization during sinus floor elevation was reduced, allowing simultaneous transalveolar flapless implantation. Schleier et al used rigid endoscopes for dental mplant placement with antroscopic control to imrove minimally invasive transalveolar augmentation. upport endoscopy has also been used diagnostically

A method for defining targets in contemporary incisor inclination correction

Different craniofacial properties require individual targets in incisor inclination. These requirements are mostly scheduled on the basis of cephalometric diagnosis, but, however, performed using straightwire appliances, which refer to third-order angles and not to cephalometric data. The objective of this study was to analyze the relationship between incisor third-order angles, incisor inclination, and skeletal craniofacial findings in untreated ideal occlusion subjects with natural dentoalveolar compensation of skeletal variation, in order to link the field of cephalometric assessment of incisor inclination with that of contemporary orthodontic incisor inclination correction. This study utilized lateral cephalograms and corresponding dental casts of 69 untreated Caucasians (21 males and 48 females between 12 and 35 years of age) with neutral (Angle Class I) molar and canine relationships and an incisor relationship that was sagittaly and vertically considered as ideal by three orthodontists (i.e. well supported by the antagonistic teeth and without the need for either deep or open bite correction). Upper (U1) and lower (L1) axial incisor inclinations were assessed with reference to the cephalometric lines NA and NL, and NB and ML, respectively. Sagittal and vertical skeletal relationships were classified using SNA (SNB) and NSL-ML (NSL-NL) angles. Third-order angles (U1TA and L1TA) were derived from direct dental cast measurements using an incisor inclination-recording appliance. The relationships between cephalometric and third-order measurements evaluated by calculating Pearson product-moment correlation coefficients (a = 0.05) showed strong correlations between cephalometric axial inclination data (U1NA/deg, L1NB/deg, U1NA/mm, L1NB/mm, U1NL, and L1ML) and sagittal-skeletal data, but no significant relationship between skeletal-vertical findings and incisor inclination. The mean U1TA was 4.9 (standard deviation [SD] 5.85) and the mean L1TA -3.0 (SD 6.9) degrees. Regression analyses were used for axial inclination (ANB angle designated as the independent variable) and for third-order data (U1NA, L1NB, U1NL, and L1ML designated as independent variables). Based on the correlations found in this study, a novel method for defining targets in upper and lower incisor third-order correction according to natural standards is presented. As a consequence, third-order movements can be adapted to cephalometric diagnosis with enhanced accuracy.

A comparative study on the extractions of partially impacted mandibular third molars with or without a buccal flap: a prospective study.

PURPOSE The present report describes a flapless extraction method for partially impacted mandibular third molars and compares the effects of flap and flapless extractions of the teeth in terms of postoperative pain, swelling, and pocket depth of the second molar. PATIENTS AND METHODS A prospective study was performed of 27 patients who underwent bilateral extraction of partially impacted mandibular third molars. Two molars in the same patient were extracted on each side, either with or without a buccal flap. RESULTS The postoperative pain, swelling, and pocket depth of the second molar were all significantly greater on the side that underwent flap extraction than on the side that underwent flapless extraction (P < .05). CONCLUSIONS Our results support the clinical use of flapless extractions when the distal surface of the crown is completely anterior to the anterior border of the mandibular ramus and the occlusal surface of the impacted tooth is level or nearly level with the occlusal plane of the second molar.

Presencia Bilateral del Canal Incisivo de la Mandíbula: Una Estructura Anatómica con Relevancia Clínica

La region anterior de la mandibula generalmente se considera un area quirurgica segura, con pocos riesgos de dano a estructuras anatomicas importantes. Sin embargo, esta region contiene un canal intraoseo, el canal incisivo de la mandibula (CIM), que es la continuacion del canal mandibular mesial al foramen mental, donde se encuentra el nervio incisivo de la mandibula acompanado de estructuras vasculares. Su presencia y el curso de la inervacion mandibular anterior siguen siendo un tema de debate y algunos autores incluso niegan su existencia. Este reporte define el curso anatomico del CIM bilateralmente mediante tomografia computarizada, confirmando la presencia del nervio incisivo de la mandibula mediante tecnica microquirurgica asistida por endoscopia. El conocimiento de la presencia, longitud y diametro del CIM pueden jugar un rol importante en el exito de la oseointegracion de un implante y prevenir alteraciones sensoriales postoperatorias.

Functional treatment of snoring based on the tongue-repositioning manoeuvre.

Orofacial biofunction comprises muscular and physical effects, which may contribute to stabilization of the oropharyngeal airway. The tongue-repositioning manoeuvre (TRM) provides physical stabilization of the tongue and the soft palate together with, as a prerequisite, a nasal breathing mode. The aim of the present study was to evaluate the influence of a TRM treatment concept on primary snoring. The TRM was used to achieve a closed biofunctional rest position of the orofacial system and to re-educate the nasal breathing pattern. Pressure indicating oral shields were used for home exercises as a biofeedback instrument and to support nocturnal mouth closure. Treatment was undertaken on 125 consecutive primary snorers [101 males, mean age 52.4 years, range 34-75, mean body mass index (BMI) 28.1, range 18.9-38.5, and 24 females, mean age 55.2 years, range 36-70, mean BMI 26.8, range 22.7-31.9]. Bed partner ranking was performed, and snoring was judged using a 10-cm visual analogue scale (VAS). The VAS score was 8.4 (range 6-10) before treatment and decreased to 4.1 (range 0-10) after treatment [mean observation time 4.6 months (1-10)]. Analysis of variance showed a significant influence of treatment in subjects with a normal body weight (BMI 18.5-25). The data provide evidence that dynamic stabilization of the orofacial system with the TRM in conjunction with nocturnal wear of an oral shield is beneficial for reducing the symptoms in primary snorers with a normal BMI.

On the interaction between incisor crown-root morphology and third-order angulation.

OBJECTIVE To evaluate the significance of crown-root angles (CRAs) by testing the null hypothesis that there are no significant differences in deviations of third-order angles to axial inclination values between Angle Class II division 2 incisors and a neutral occlusion control sample. MATERIALS AND METHODS The study group comprised n(total) = 130 whites with either Angle Class II division 2 (n(1) = 62; group A) or neutral (n(2) = 68; control group B) occlusal relationships. Upper central incisor inclination (U1) was assessed with reference to the cephalometric lines NA and palatal plane (U1NA/deg, U1PP/deg). Craniofacial sagittal and vertical relations were classified using angles SNA, SNB, ANB, and NSL-PP. Third-order angles were derived from corresponding dental cast pairs using an incisor inclination gauge. Welchs two-sample t-tests (alpha-level: .05) were used to test the null hypothesis. Single linear regression was applied to determine third-order angle values as a function of axial inclination values (U1NA, U1PP) or sagittal craniofacial structures (ANB angle), separately for group A and B. RESULTS The discrepancy between axial inclination (U1NA, U1PP) and third-order angles is significantly different (P < .001) between groups A and B. Regression analysis revealed a simply moderate correlation between third-order measurements and axial inclinations or sagittal craniofacial structures. CONCLUSION The hypothesis is rejected. The results of this study warn against the use of identical third-order angles irrespective of diminished CRAs typical for Angle Class II division 2 subjects. Routine CRA assessment may be considered in orthodontic treatment planning of Angle Class II division 2 cases.

Quantitative Analysis of the Velopharyngeal Sphincter Function During Speech

OBJECTIVE This study reports a new concept for quantitative analysis of velopharyngeal function using electromagnetic articulography and simultaneous transoral video endoscopy. PARTICIPANTS The velopharyngeal closure mechanism was studied in 16 healthy German subjects during production of the vowel-consonant-vowel sequences /afa/ and /apa/. DESIGN Velar movements in the sagittal and vertical direction were measured by electromagnetic articulography (EMA) while video endoscopy was used for recording in the sagittal and transverse directions. MAIN OUTCOME MEASURE A transverse sagittal quotient (TSQ) was defined after the measurement of sagittal and transverse diameters of the velopharyngeal port (VPP) in the video-endoscopic pictures on the basis of a frame-by-frame analysis. RESULTS The sphincter morphology was objectively determined with the TSQ base value. A terminal sphincter deformation (TSD) for closure phases of articulatory movement was revealed by a qualitative shape analysis of the TSQ curves. CONCLUSIONS The assessment of the TSQ of velopharyngeal port diameters and the TSD in the terminal closure period lead to a new dynamic interpretation of velopharyngeal closure patterns.