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Summary: Over the past decade, coinciding with the appearance of a number of new ultrasonic surgical devices, there has been a marked increase in interest in the use of ultrasound in oral surgery and implantology as alternative osteotomy method. The aim of this study was the comparison of the effect of osteotomies performed using ultrasonic surgery (Piezosurgery®), sonic surgery SONICflex® and the conventional bur method on the heat generation within the bone underneath the osteotomy and light-microscopy observations of the bone at different cutting positions in porcine mandibular segments. It was found that the average heat generated by SONICflex® sonic device was close to that by conventional rotary bur (1.54–2.29°C), whereas Piezosurgery® showed a high generated heat up to 18.17°C. Histological investigations of the bone matrix adjacent to the defect radius showed intact osteocytes with all three instruments and similar wide damage diameter at the bottom region. SONICflex® showed smooth cutting surfaces with minimal damage in the upper defect zone. Finally, presented results showed that sonic surgery performed with SONICflex® is an alternative osteotomy method and can be used as an alternative to the conventional bur method. [Copyright &y& Elsevier]

Summary: A group of 80 children ranging in age from 6 to 10 years (subdivided into groups 1–5 according to chronological age) has been compared with an adult group on the basis of condylar path length and maximum mouth-opening capacity. The condylar path length and the mouth-opening capacity were measured using the ultrasonic JMA®-System for registration. In the development of the temporomandibular joint (TMJ), condylar path length and mouth-opening capacity were found to increase with age in the juvenile group. In the oldest juvenile subgroup (subgroup 5; average age: 10.3 years) the condylar path length reached 17.6mm on the left and 17.3mm on the right. This is equivalent to 90.3% (left) and 91.1% (right) of the size in the adult group. The mean maximum mouth-opening capacity of the oldest juvenile subgroup was 56.3mm and reached 98.9% of the size in the adult group. [Copyright &y& Elsevier]

Summary: The reconstruction of functionally appropriate contacts between antagonistic teeth substantially determines the quality of prosthetic-restorative work. In a population-based sample comprising 2597 subjects, static occlusal contacts were registered and analysed using the GEDAS (Greifswald Digital Analyzing System), which digitally represents the contact point situation by means of silicone bite impressions. The number of contacting teeth is approximately equal on the left- and right-hand side amounting to 8.3 on the left and 8.4 on the right. Furthermore, it was shown that 39% of the maxillary bridge pontics and 33% of the mandibular bridge units are not in contact. Antagonistic contacts are missing in 41% of the maxillary and 39% of the mandibular removable denture teeth. These results show that the fabrication of fixed dentures, particularly in bridge pontics, and the inspection of removable dentures needs to be done with more care to this detail. [Copyright &y& Elsevier]

Summary: Centric relation prematurities of frontal teeth are frequently found with patients who have severe orthodontic anomalies or received extensive restorative treatment. They can cause a range of symptoms ranging from loosening of the teeth to temporomandibular disorders (TMD). The objective of this work has been to derive a mathematical description of the mandibular and periodontal forces generated by anterior prematurities for different incisor relations. In order to quantify the effect of contact area (location and inclination) and the tooth inclination, a two-dimensional mathematical approach was used. Vectorisation of the forces and bending moments makes it possible to predict under which conditions the load increase mainly affecting the anterior teeth can and may cause localized pain and eventually loosening and flaring/crowding of the upper/lower incisors and under which conditions the temporomandibular joint will suffer a large increase in retrusive force, which potentially leads to TMD. For 10 patients with anterior prematurities, analysis of the incisor relation was carried out. For all cases the conclusions drawn from the mathematical model were in full agreement with the reported symptoms, which could be successfully treated. [Copyright &y& Elsevier]

Summary: For the physiological intact stomatognathic system, the three main functional states (occlusal articular functions, free mandibular movements, and ideal bolus function) were biomechanically discussed concerning the structure of movement, rolling–gliding characteristics, and force transfer in the temporomandibular joint (TMJ). In all three cases, rolling is not possible in the TMJ since the instantaneous rotational axis is positioned outside of the joint – rolling is not necessary because the TMJ is not loaded by appreciable forces. In the aged stomatognathic system with a lost discus and considerable loads in the TMJ, however, the attrition of the joint is eased by rolling movement at the articulating surfaces. The destruction of the discus can be seen as a physiological adaptation which brings back the joint to an original odontogen condition. [Copyright &y& Elsevier]

Summary: Treatment of mandibular condylar process fractures may be conservative or surgical. Both treatment approaches aim to reconstruct the articulating joint surfaces in a physiological position to the discoligamentary structures. The study comprised 1812 patients of Wuerzburg University who presented with a fracture of the mandibular condylar process between 1981 and 2001. Besides conservative management options, surgical interventions using mini-plate osteosynthesis and the Wuerzburg lag screw plate were studied for post-treatment changes. Statistical analysis revealed that surgical osteosynthesis is superior to merely conservative therapy in terms of post-treatment dysgnathic severity. Hence, surgical osteosynthesis is advocated especially in patients with high condylar fractures or dislocated fractures in order to ideally achieve ‘restitutio ad integrum’. [Copyright &y& Elsevier]

Summary: Brain imaging based on functional magnetic resonance (fMRI) is a useful tool for examination of neuronal networks and cerebral structures subserving visiospatial function. The purpose of this study was to compare the brain activity during chewing and occlusal function in centric occlusion on natural teeth or on occlusal splints. Four tasks were performed by 13 healthy, fully dentate subjects (21–32 years old, 6 female and 7 male): occlusal tap-tap movements in centric occlusion by natural teeth, after application of a maxillary occlusal splint and chewing movements on left and right sided rubberdam strips. In order to reveal which areas of the brain were more strongly activated, conjunction analyses between the different tasks were performed for each subject and for the average values of brain signal activity of all subjects. Whilst several known foci of activity were subtracted, differences of significant activity rested in areas of the sensorimotor cortex. Mainly ipsilaterality of hemispheres concerned the left and right sided chewing, whereas the conjunction between tap-tap movements on natural teeth and splint occlusion indicated only one weak, but significant activation foci. The study confirms fMRT as one of the most useful developing methods to clear up neuro-cortical effectiveness of occlusion and occlusal therapy. [Copyright &y& Elsevier]

Summary: For treatment of temporomandibular disorders Michigan-type splints are frequently used, as are mandibular advancement appliances for patients diagnosed with anterior disk dislocation. As both types show good results, the combination of these two mechanisms into one bimaxillary appliance was tested on eight patients where splint therapy had brought reduction but not complete elimination of the symptoms. An existing maxillary Michigan splint was modified so that advancement springs could be fitted and the generated forces were transmitted to a mandibular retainer, which did not interfere with the function of the splint. Treatment progress was monitored with computerized axiography and in all cases the axiographic tracings after the bimaxillary treatment showed no pattern indicative of disk dislocation under normal jaw movements. Myofascial pain symptoms, already improved by the pre-treatment with the Michigan splint, were found to be reduced further or eliminated completely. The approach of retrofitting a Michigan splint with the springs allowed for a versatile appliance, which required no occlusal alteration to the finely adapted splint but could as easily be brought back to the simple splint-functionality either for daytime use or for a period of stabilization of the result after successful treatment. Compliance was found to be very good and the short treatment period, together with the small force levels did not produce any detectable dental side effects. [Copyright &y& Elsevier]

Summary: There is a series of tools useful for gathering diagnostic information on patients with temporomandibular joint disorders. Tracings of the joint movement (axiography) provide useful information about the motion of the joints. Since the availability of electronic axiographic tracers, the movement of the condyles can be resolved with high resolution both in space and in time. In order to obtain information about the anatomical relation of the joint surfaces and the disc, magnetic resonance tomography imaging (MRI) is routinely carried out. It is common practice to take MR images of the joints with the mouth closed and fully open. In order to correlate the MR images with the axiographic tracings, a series of images can provide much more information. In this study we examined patients with distinct temporomandibular joint (TMJ) clicks. In one case, the click occurs once a day, while in the other case the click happens every time the mouth is opened. In order to obtain information about both motion and anatomical relation of the TMJ at and around the position where the clicks occur, we recorded a series of MRI scans with the mouth gradually opened and before and after joint clicks. Real-time axiographic tracings during the click were taken with an optimized system where the polar moments were reduced as much as possible to follow the movement during the click. These tracings were correlated with the MRI scans to determine the exact internal conditions of the TMJ and the changes during the click. In particular cases, the additional information provided by this procedure can be useful in deciding whether and which therapeutic intervention is advisable. [Copyright &y& Elsevier]

Summary: The expansion of biodegradable osteosynthesis systems in clinical application correlates well to the progress in development of new materials as to the improvement of application methods. One of those new application methods is the ultrasound-aided insertion of Resorb-X® pins. The aim of this study was the histological evaluation of possible thermal damage to bone due to the ultrasound insertion. For this purpose, condylar neck fractures in 12 sheep were produced, repositioned and fixed by Resorb-X® plates and pins. The animals were sacrificed in two groups, one after 2 weeks and one after 9 weeks. The bone–pin interlinkage and the structure of the bone were histologically evaluated. After 2 weeks a tight bone–polymer interlinkage was seen. Neither a pronounced foreign body reaction nor an interposition of fibrous tissue at the interface or a thermally induced necrosis was observed. The late phase of wound healing after 9 weeks showed pathomorphological characteristics within the normal range of bone healing. The bone seemed to be free of any alteration caused by process engineering. We conclude that thermal stress caused by ultrasound-aided pin insertion does not lead to cellular reaction in the bone. The fast and easy application of this improved biodegradable osteosynthesis system will bring a clear advantage in clinical use. [Copyright &y& Elsevier]

Summary: The condylar cartilage of the mandible is considered a secondary growth center and represents a joint cartilage different from other cartilage structures regarding its histological structure, its histochemical and immunohistochemical properties and its growth pattern. This study aimed to histologically and histomorphometrically investigate the condylar cartilage after anterior mandibular displacement similar to functional orthopedic treatment. A total of 12 pigs (sus scrofa domesticus) aged 10 weeks were divided into an experimental group and a control group comprising 6 animals each. The experimental animals were provided bilaterally with synthetic occlusal build-ups in the posterior area which induced anterior displacement of the mandible in terminal occlusion. After 4 weeks, the temporomandibular structures were removed en bloc and the condylar cartilage was analyzed histologically and histomorphometrically. As a result, the experimental animals displayed a significantly increased total cartilage thickness of the posterocranial mandibular condyle which was primarily caused by an increase in thickness of the hypertrophic and chondogenic layers. Similarly, the proliferative layer showed a significant increase, whereas significant differences in thickness were absent in the articular layer. Increased cell proliferation was not observed in the experimental animals as compared to the controls. The changes found in the condylar cartilage area suggest that the zonal structure of the conylar cartilage may be modified by an altered spatial relationship between the mandibular condyle and the glenoid fossa. [Copyright &y& Elsevier]

Summary: Animal experiments are used in embryological and teratological studies of matters relevant to humans. In gravid rats, a decrease in the levels of folic acid and vitamin B12 was observed in maternal blood and in amniotic fluid. At the time of secondary palatal closure (14th day of pregnancy), the folic acid level of the amniotic fluid was 73% lower than that of the maternal blood. A drop in vitamin B12 in conjunction with an increase in amniotic homocysteine levels is seen as a risk factor for malformation of the palate. The understanding of causes of cleft generation could lead to a prophylactic treatment approach. [Copyright &y& Elsevier]

Introduction: The purpose of this study was to evaluate skeletal and dentoalveolar changes due to unilateral distalization and to determine side effects. Methods Cephalograms and dental casts before and after distal movement of the maxillary molars with pendulum appliances in 15 consecutively treated patients (5 girls and 10 boys, 12.06 ± 1.32 years), were included in this study. The duration of distalization was 8.46 ± 2.23 months. Results Cephalometric analysis showed no remarkable growth between the 2 measurement times. The mean value for distalization of the first molars was 3.83 ± 1.09 mm, with distal tipping of 6.45°. The maxillary second molars were also moved distally 2.83 ± 1.32 mm and tipped distally 14.7°. No significant changes in the position of the third molars were measured. The mean reciprocal mesial movement of the premolars was 1.18 ± 1.31 mm, with distal tipping of 1.94°. The incisors moved 0.84 ± 0.79 mm mesially, with mesial tipping of 0.02° and extrusion of 1.21 mm. There was also a significant influence on the contralateral anchorage unit. However, unilateral distalization reduced incisor proclination and induced moderate distal movement of the contralateral anchorage unit based on rotation around a virtual axis perpendicular to the Nance button. Conclusions Effective distal molar movement and less anchorage loss at the front teeth are advantages of unilateral distalization. [Copyright &y& Elsevier]

Summary: The facial musculature is part of a biocybernetic feedback system within the stomatognathic system, the continuity of which is disturbed by clefts of the lip, jaw, and palate (cheilognathopalatoschisis). This results in topographic, fine-structural and functional alterations of the facial musculature. In two heads with unilateral clefts and two heads with bilateral clefts, the facial musculature was dissected and the M. orbicularis oris macroscopically and topographically examined. We found changes in the attachment of the M. orbicularis oris. The modiolus, which is co-responsible for the proper topographic relation of the M. obicularis oris to the other facial muscles, was unchanged. Further, we examined the vascular system of the muscle, which likewise adapts to the altered situation. Lip/jaw/palatal clefts result in anatomically functional and fine-structural alterations of the M. orbicularis oris, while the rest of the facial musculature remains unchanged. [Copyright &y& Elsevier]

Summary: The masticatory musculature is an integral functional part of the stomatognathic system and influences craniofacial morphogenesis and morphology. This animal study aimed to investigate the morphological consequences of restricted regional blood supply to the m. masseter. A total of 20 adult male Wistar rats (Rattus norvegicus Berkenhout) were divided into an experimental group and a control group comprised of 10 animals respectively and kept under standardized conditions. The experimental group underwent a dextrolateral complete surgical ligation of the a. carotis communis and, after 5 weeks, specimens were taken from the masseters. The muscle samples were analyzed immunohistochemically for fiber distribution and capillary density. Analysis revealed a discrete increase in the proportion of type I fibers with a significant increase of capillary number per area. Although no agreement exists on the alterations occurring in chronically ischemic muscles, it may be assumed that chronic ischemia evokes histomorphological adaptation processes similar to endurance training effects. [Copyright &y& Elsevier]

SUMMARY: Purpose: Gingival hyperplasia is a well known side effect of Cyclosporine A therapy. The aetiology of this is not totally understood and there is debate whether it is hyperplasia of the gingival epithelium or of the submucosal connective tissue, or both, and what roles play factors like age and gender of the patients, duration and dosage of the drug. Material and methods: The influence of different Cyclosporine A concentrations (10−6 g/ml; 5 × 10−7 g/ml; 10−9 g/ml) and of no medication (controls) on growth and proliferation of cultured human gingival keratinocytes was investigated after a culture period of 3, 6 and 9 days. Cell proliferation was assessed by counting anti Ki-67 stained nuclei, cell growth by counting total number of nuclei and by the EZ4U-assay. Results: There was no significant correlation of the cell proliferation rate and cellular growth with either gender (p > 0.568) or duration of medication (p > 0.876); but Cyclosporine A concentration showed a highly significant influence on cellular growth (p = 0.0001). Inhibition of cell growth was dependent on drug dosage, but a low concentration of 10−9 g/ml even stimulated cell growth. Conclusions: There is evidence that Cyclosporine A in low concentrations (10−9 g/ml as applied in long-term therapy) stimulates gingival keratinocyte growth and therefore might be related to hyperplasia of the gingiva. However, high Cyclosporine A concentrations may inhibit cell growths and factors like gender of the patient did not show any influence in-vitro. [Copyright &y& Elsevier]

SUMMARY: Introduction: Surgical correction of malocclusion changes the force to moment ratio of masticatory muscles inserting at the mandible caused by shortening, lengthening and rotation of the bone following osteotomy. During muscle adaptation the expression of mRNA for the myosin heavy chain (MyHC) of type I and type II fibres may be changed. Material and methods: The adaptation of the masseter muscle was investigated at the mRNA level in 10 patients 6 months after orthognathic surgery in the mandible. The competitive polymerase chain reaction (cPCR) is a suitable method for quantification of MyHC mRNA. For application of this minimal invasive method an amount of 35 mg muscle tissue was sufficient. Results: 6 month postoperatively there was a deficiency of about 87% of MyHC mRNA for fibre type I and II in both groups of patients. The deficiency in patients with mesial position of the mandible was higher but not significant different to patients with distal malocclusion. Conclusion: Patients should use the postoperative interval for training their masticatory muscles. This improves the stability of treatment result and prevents relapse. [Copyright &y& Elsevier]

SUMMARY: Purpose: The aim of this study was to evaluate the ectopic bone formation using tissue engineered cell-seeded constructs with two different scaffolds and primary human maxillary osteoblasts in nude rats over an implantation period of up to 96 days. Material and methods: Collagen I-coated Poly(3)hydroxybutyrate (PHB) embroidery and hydroxyapatite (HAP) collagen tapes were seeded with primary human maxillary osteoblasts (hOB) and implanted into athymic rnu/run rats. A total of 72 implants were placed into the back muscles of 18 rats. 24, 48 and 96 days after implantation, histological and histomorphometric analyses were made. The osteoblastic character of the cells was confirmed by immunocytochemistry and RT-PCR for osteocalcin. Results: Histological analysis demonstrated that all cell-seeded constructs induced ectopic bone formation after 24, 48 and 96 days of implantation. There was more mineralized tissue in PHB constructs than in HAP-collagen tapes (at day 24; p < 0.05). Bone formation decreased with the increasing length of the implantation period. Osteocalcin expression verified the osteoblastic character of the cell-seeded constructs after implantation time. No bone formation and no osteocalcin expression were found in the control groups. Conclusions: Cell-seeded constructs either with PHB embroidery or HAP-collagen tapes can induce ectopic bone formation. However, the amount of bone formed decreased with increasing length of implantation. [Copyright &y& Elsevier]

SUMMARY: Introduction: Patients with clefts of lip, alveolus and palate show a high incidence of maxillary sinusitis. In order to evaluate sinus size as a factor in sinusitis, this study investigates maxillary sinus morphology in an adult skull with an untreated bilateral cleft. Material and methods: The maxillary sinus volume (MSV) of a mixed-sex sample of 140 adult skulls from three different populations was assessed and compared with the MSV of a skull of a 25 year old man showing an untreated complete bilateral cleft. A least squares regression analysis was used to investigate the relationship between MSV and different external cranial dimensions. Results: The cleft skull shows a well-developed set of paranasal sinuses. There are close, significant relationships between MSV and the cranial measurements. The cleft skull had a MSV that does not deviate substantially from that predicted from the size of its facial skeleton. Conclusion: This study indicates a close link between the size of the facial skeleton and the MSV in humans, even in case of an untreated bilateral cleft. This, in conjunction with the existing literature, makes it extremely unlikely that the sizes of the paranasal sinuses are a factor for sinusitis in patients with cleft lip, alveolus and palate. [Copyright &y& Elsevier]

SUMMARY: Introduction: The aim of this study was to show the prevalence of single-tooth gaps in a population-based study. Material and methods: The data of 3989 subjects (20–74 years of age) were taken from the Study of Health in Pomerania (SHIP-0) and classified by age, gender, and level of education. A single-tooth gap was defined as a gap of one tooth missing bordered by one or more natural teeth on either side. Results: The tooth missing most in all age groups was the first molar. There were more single-tooth gaps in the maxilla than in the mandible. The lowest single-tooth gaps were found in the mandibular anterior region (<1.1%). There were no significant differences in gender (p > 0.05). The highest frequency of single-tooth gaps among all groups was found in subjects with a medium level of education and the lowest frequency was found in subjects with a high level of education. One single-tooth gap was found in 25%, whereas 16% of all subjects had 2 single-tooth gaps. The prevalence of having 1 single-tooth gap was between 3.8% and 13.1% whereas it was less than 0.5% for subjects with 5 and more single-tooth gaps. Conclusion: There was a high potential for dental implants to fill single tooth gaps. [Copyright &y& Elsevier]

SUMMARY: Review: Orthognathic surgery has become a standard procedure in cranio-maxillo-facial surgery during the past five decades. Based upon the elementary works by Obwegeser who introduced sagittal split ramus osteotomy in the early 1950s, this procedure has become the worldwide gold standard in mandibular orthognathic procedures by now. When devices for ensuring the centric condylar position throughout the entire surgery were introduced by Luhr in the early 1980s, modern understanding of complete functional rehabilitation in orthognathic surgery was further enhanced. Even though Le Fort I osteotomy was performed by Wassmund already in the 1920s, it took almost another 50 years until this procedure became accepted in surgery, mainly due to concerns for severe haemorrhage that may occur during surgery. Application of a compound condylar positioning device which was established to ensure and keep the exact condylar position throughout maxillary, mandibular, as well as during bimaxillary osteotomies, and to permit the targeted use of distraction devices. Among those, cleft patients also sometimes need orthognathic correction of typical micrognathia and pseudoprogenia in late adolescence or at early adult age as secondary cleft surgery procedures. In this overview, special emphasis will be placed on orthodontic treatment as well as on the technical prerequisites for the surgical procedure. [Copyright &y& Elsevier]

SUMMARY: Patients with clefts of lip, alveolus and palate or some facial syndromes need complex and long-lasting orthodontic therapy. The possibility of orthodontic anchorage is often limited by congenital absence of teeth, disturbed skeletal growth or failing compliance with extraoral sources of force. Correct positioning and insertion provided, miniscrews can serve as anchorages and shorten the period of active treatment in patients with clefts. With the help of a case presentation, an outline of using orthodontic miniscrews (like: Titan, Forestadent®) for anchorage in patients with clefts of lip, alveolus and palate is given along with a discussion of advantages and disadvantages. Thus miniscrews are suited for use in cleft patients. However, they require careful orthodontic and surgical planning. [Copyright &y& Elsevier]

SUMMARY: Introduction: Therapy of cleft patients aims to control bone growth and tooth development so as to ensure a secure occlusion with good function. This paper aims to uncover the potential and limits of achieving neutral occlusion in patients with clefts of lip, alveolus and palate. Two treatment approaches are presented and compared with respect to the best long-term results. Patients and methods: The first method implies occlusal rehabilitation using maximum intermaxillary orthodontic fixation with the Jasper Jumper. Thus, orthodontic dental-alveolar compensation of the anomaly is obtained. The second method represents orthognathic surgery to achieve ideal intermaxillary relations and a neutral occlusion. Two patients are described – one each for both treatment regimens. Discussion: The methods presented are meant to illustrate possible options for sagittal jaw development/movement in patient management. Orthodontic treatment has to rely on cooperation with maxillofacial surgery to achieve a neutral occlusion. Optimal management is ensured by a combination of both orthodontic and maxillofacial therapy. The orthodontic and surgical techniques for managing unilateral or bilateral clefts are continuously being further developed. Conclusion: Although orthodontic treatment can achieve good neutral occlusion in some patients, there are limitations and surgical measures may become necessary. [Copyright &y& Elsevier]

SUMMARY: Introduction: Osteoplasty in cleft patients provides a basis for shaping a closed dental arch. This study aimed at a radiological appraisal of transplantation success following secondary osteoplasty by means of alveolar bone height as related to some selected influencing factors. Material and methods: In this study, postoperative radiographs of 46 patients with unilateral or bilateral clefts of lip, alveolus and palate were analyzed retrospectively. Alveolar bone height was typed according to Åbyholm and Bergland and evaluated in consideration of dentition at the time of surgery and existence of the lateral incisor. Results: In total, 76% (n = 35) successes (type I/II) were observed. 6 out of 46 patients (13%) had to be re-operated for osteoplasty at a later date. A non-significantly higher rate of successes occurred during the early mixed dentition. In patients with existing lateral incisor, a higher rate (78% vs. 68%) of alveolar bone heights type I/II was obtained. Conclusion: The successful surgical outcome in terms of alveolar bone height is facilitated by treatment onset preferably during early mixed dentition and in presence of the lateral incisor. Although maximal success rates cannot be obtained using this method, the utility and effectiveness of secondary osteoplasty in cleft patients has been confirmed. [Copyright &y& Elsevier]

SUMMARY: Problem: What kind of skeletal differences do exist between juvenile patients with unilateral cleft lip, alveolus and palate treated with or without secondary osteoplasty, and between cleft patients and non-cleft patients? Patients and methods: Thirty-nine patients with unilateral cleft lip, alveolus and palate at a mean age of 15.8 years who were surgically treated with (n = 18) and without (n 21) secondary osteoplasty were compared with a control group of non-cleft patients (mean age 15.1 years). The patients were analyzed using lateral cephalograms. Cephalometric analysis included common sagittal and vertical variables as well as measurements of anterior tooth position and soft-tissue profile. Results: Analysis of lateral cephalograms revealed no significant differences between the two groups of cleft patients. The differences in comparison with the control group mainly revealed maxillary retroposition, a vertically open configuration, a steep position of the upper and lower anterior teeth and a decreased Holdaway-angle (flat midface). Conclusion: Secondary osteoplasty exhibited no significant influence on craniofacial growth in children with unilateral cleft lip and palate. Both groups of cleft patients are not markedly different regarding sagittal and vertical skeletal configurations. [Copyright &y& Elsevier]

SUMMARY: Introduction: The case of a newborn female patient with unilateral cleft lip, alveolus and palate is presented with a markedly sunken nasal wing at the cleft side. This finding may lead to a very unsatisfactory aesthetic result after primary cheiloplasty and nasoplasty. Patient and method: Five months prior to surgery, the patient was treated with a palatal plate and additionally with a nasoalveolar conformer for 4 months thereof. The device consisted of an acrylic pelotte (attached to the maxillary plate with a wire) which lifted the nasal dome and was activated regularly. Under this presurgical treatment, the cleft edges moved closer to each other by 1.8 mm at the alveolar ridge and by 4.5 mm in the palatal area. The nasal wing was lifted by 5 mm. This was enabling elevation of the nasal wing during primary surgery in the case described. Questions are raised as to the remaining effects on nasal symmetry until completion of growth and, on the other hand, as to the chances to reduce postsurgical alar relapse by continued nasal molding beyond primary surgery. Conclusion: Presurgical nasal molding seems to improve aesthetics of the nose in patients with unilateral clefts of lip, alveolus and palate and distinctly flattend nasal wings. [Copyright &y& Elsevier]

SUMMARY: Introduction: Particular importance is attached to lip repair cleft surgery, as numerous functional and aesthetic aspects have to be taken into account simultaneously. Spatial assessment of function and depiction of dynamic deviations is reasonable for describing surgical outcome in addition to long standing static analysis. This study aimed at 3D analysis of the oral area after reconstruction in patients with unilateral cleft lip, alveolus and palate. Patients and Methods: Twelve patients with unilateral cleft lip, alveolus and palate who underwent surgery according to Tennison–Randall were enrolled in this study. Soft tissue dynamics was analysed during passive stretching and active contraction of the lips, and photogrammetry was used for comparing relative changes of length and displacement vectors. The spatial coordinates of surgically significant and reproducible landmarks along the red-white lip junction were analyzed. Results: Static analysis of the lips revealed a good result with far-reaching symmetry in all cases. Regarding dynamic behaviour, two groups could be distinguished showing clear differences of passive distension and contraction behaviour. Conclusion: Despite nominally identical surgical techniques and comparable static-morphological outcomes, dynamic analysis revealed differences pointing to a need for optimization. [Copyright &y& Elsevier]

SUMMARY: Introduction: For embryonal facial development several fusion processes between different facial prominences are necessary. If fusion fails to appear, various facial clefts may occur, known as median (e.g. lower median cleft lip), oblique (e.g. open nasolacrimal duct) or lateral facial clefts (macrostomia, lateral cleft). Material and methods: The development of 3 different facial regions (bucca, mentum, and nasolacrimal duct) was examined in rats using serial histological sections on day 13.5 after conception. Common procedures were used (staining for active caspase-3 and for Ki-67) for histological assessment about the role of apoptotic and proliferative processes in the fusion zones of buccal, mental and nasolacrimal areas. Results: Multiple apoptotic events were detected in epithelial cells of the respective regions, the proliferative centers were located in the mesenchymal surroundings of fusion zones. Conclusion: A substantial precondition for fusion of facial prominences are proliferative and apoptotic processes in epithelial and mesenchymal cells. Apoptosis contributes to the development of bucca, mentum and the nasolacrimal duct. Absence of apoptoses may be responsible for facial clefts. [Copyright &y& Elsevier]

SUMMARY: Introduction: The first embryonic part of the nasal cavity is the primary nasal duct, beginning with the olfactory placode and ending with the oronasal membrane. Aim of this study was to investigate the cellular processes (apoptosis, proliferation) being responsible for development and opening of the primary nasal duct. Material and methods: In this study developmental processes in at least three regions of the primary nasal duct (opening, middle, end) were examined by sectioning 38 rat fetuses on day 13.5 after conception. Apoptotic cells were detected by active caspase-3 antibodies and proliferating cells were examined by Ki-67 antibodies. Results: Multiple apoptotic events were diagnosed on the basis and proliferative cells on the top of this duct. Conclusion: Apoptosis and proliferation play an important role in the process of opening the bottom of the primary nasal duct and for development of the nasal septum, philtrum as well as the primary palate. Mesenchymal proliferation seems to play a minor role in the process of opening the primary nasal duct. [Copyright &y& Elsevier]

Summary: Tooth eruption is a complex biological process which starts from the site of development in the jaw bone until the teeth reach their final functional position in the chewing plane. Various factors can disturb this process. Besides mechanical obstacles on the eruption path, a pathological position or axial orientation of the tooth germ, morphological aberrations of the tooth or pathological alterations of the periodontium, primary disorders of the eruption mechanism may lead to complete or partial retention of the tooth in the jaw bone. These morphological features bear upon the prognosis of orthodontic correction which is dependent upon the underlying cause. First and second molars are rarely affected by eruption disorders, with a prevalence of 0.01 to 0.08 per cent, however, marked consequences for function such as posterior open bite or elongation of the antagonists may result. Following an overview of pathogenetic factors of tooth eruption disorders, selected cases of impacted first and second permanent molars are presented with respect to their morphological causes. [Copyright &y& Elsevier]

Summary: Supernumerary teeth are extra teeth or toothlike structures which may have either erupted or unerupted in addition to the 20 deciduous teeth and the 32 permanent teeth. This article provides an overview of frequency, distribution and classification of supernumerary teeth. The etiology of supernumerary teeth is still unknown, yet various theories have been presented based on epidemiological studies. Four clinical cases representing the possible manifestations of supernumerary teeth are discussed. [Copyright &y& Elsevier]

Abstract: Orthodontic treatment of retrognathism is aimed at correcting the position of the jaws and at rectifying functional problems. Changes induced in the bone morphology of the mandible and in the dentoalveolar region by different appliances are well documented. Less is known and measurable with respect to the functional status and muscular capacity of orofacial muscles induced by the appliance within the framework of the training effect in Class II malocclusion cases. The aim of the present investigation was to analyze and quantify the change in fiber type levels of type I (slow Myosin heavy chain (MyHC)) and type IIb (fast b MyHC) MyHC RNA transcripts, using the competitive reverse polymerase chain reaction (cRT-PCR) during sagittal advancement of the mandible in pigs. The experiments were carried out on 10-week-old piglets (six test animals, six controls) over a period of 28 days. Six piglets received acrylic build-ups for permanent sagittal advancement of the mandible. Muscle tissue was taken from seven different regions of the masseter (m1-3), temporal (tp1, 2), medial pterygoid (pm), and geniohyoid muscles (gh). A marked increase in the absolute amount of slow MyHC RNA transcripts was detected after treatment in the anterior region and in the medial region of the masseter muscle, and in the anterior region of the temporal muscle. For fast b MyHC fibers no significant changes were registered. This can be seen as a shift directed to slow MyHC, confirming results of the training effect in sport and rehabilitation medicine. [Copyright &y& Elsevier]

Summary: Morphological parameters of the temporomandibular joint (TMJ) of Cercopithecus mona were analyzed by sagittal medial/lateral slicing of the entire joint. The slice contours of the osseous structures of the joint surfaces were approximated by circles. In this manner, the main parameter of the protrusive cranial border guidance, the protrusive dimeric link chain (DLC), could be measured. In each joint, all slices yielded protrusive DLCs which were nearly parallel to each other. In medial/lateral direction all parts of the joints participate in force transmission in initial protrusive cranial border function. [Copyright &y& Elsevier]

SUMMARY: Introduction: This study aimed to demonstrate clefts of the secondary palate in embryos found to have cleft lip in order to evaluate the validity of prenatal ultrasound examination and, thus, to assess the significance of this diagnostic method for coordination and care of parents and infant. Patients and methods: Over a period of 2.5 years, 7 fetuses with cleft deformities were examined sonographically during the 20th and 25th gestational week. The results were compared to postnatal clinical diagnosis. This study was made by two experienced examiners using 2D ultrasound devices (Acuson 128 XP-10/ C7; Toshiba Aplio XV). Postnatal clinical diagnosis was made by an orthodontist. Results: Three of the ultrasound-based diagnoses coincided with the postnatal result. In three of the examined cases the extent of the cleft was underestimated, whereas a greater extent suspected in one patient could not be confirmed clinically. Conclusion: The results of the present study support the propositions of current literature: Diagnosis of a cleft of the lip and the alveolar process could correctly be made by an experienced ultrasound diagnostician. However, problems arise with clefts of the secondary palate. [Copyright &y& Elsevier]

Introduction: The purpose of this study was to compare the shear and tensile bond strengths of 8 common adhesive systems for bonding in orthodontics. Methods: One hundred sixty freshly extracted bovine mandibular permanent incisors were randomly divided into 8 groups. Self-ligating esthetic Damon 3 brackets (Ormco, Orange, Calif) were bonded by using the following adhesive systems: Quick Bond (chemically and light-cured; Forestadent, Pforzheim, Germany), Blugloo (Ormco), Enlight LV (Ormco), Kurasper F (Kuraray Dental, Frankfurt, Germany), Transbond LR (3 M Unitek, Monrovia, Calif), Light Bond (Reliance Orthodontic Products, Itasca, Ill), and Fuji Ortho LC (GC America, Alsip, Ill). After 24 hours, half of each group was debonded measuring the shear bond strength and half measuring the tensile bond strength. Results: Blugloo showed the best shear bond strength values, whereas Transbond LR and Quick Bond (chemically and light-cured) had the lowest. Tensile strength was the highest with Fuji Ortho LC and the lowest with Quick Bond (chemically and light-cured) and Kurasper F. The tensile strength of light-cured Quick Bond was about 47% lower than that of Fuji Ortho LC. Conclusions: Blugloo, Fuji Ortho LC, Light Bond, and Enlight LV are among the materials of choice for bonding fixed orthodontic appliances to teeth. All bond strength values were clinically satisfactory except for the tensile strength of chemically and light-cured Quick Bond and Kurasper F. [Copyright &y& Elsevier]

Introduction: The purpose of this study was to compare the shear and tensile bond strengths of 8 common adhesive systems for bonding in orthodontics. Methods: One hundred sixty freshly extracted bovine mandibular permanent incisors were randomly divided into 8 groups. Self-ligating esthetic Damon 3 brackets (Ormco, Orange, Calif) were bonded by using the following adhesive systems: Quick Bond (chemically and light-cured; Forestadent, Pforzheim, Germany), Blugloo (Ormco), Enlight LV (Ormco), Kurasper F (Kuraray Dental, Frankfurt, Germany), Transbond LR (3M Unitek, Monrovia, Calif), Light Bond (Reliance Orthodontic Products, Itasca, Ill), and Fuji Ortho LC (GC America, Alsip, Ill). After 24 hours, half of each group was debonded measuring the shear bond strength and half measuring the tensile bond strength. Results: Blugloo showed the best shear bond strength values, whereas Transbond LR and Quick Bond (chemically and light-cured) had the lowest. Tensile strength was the highest with Fuji Ortho LC and the lowest with Quick Bond (chemically and light-cured) and Kurasper F. The tensile strength of light-cured Quick Bond was about 47% lower than that of Fuji Ortho LC. Conclusions: Blugloo, Fuji Ortho LC, Light Bond, and Enlight LV are among the materials of choice for bonding fixed orthodontic appliances to teeth. All bond strength values were clinically satisfactory except for the tensile strength of chemically and light-cured Quick Bond and Kurasper F. [Copyright &y& Elsevier]