S. Kiliaridis - Université de Genève (original) (raw)

Papers by S. Kiliaridis

Progress in orthodontics, Jan 11, 2013

Controversy exists in the literature between the role of orthodontic treatment and gingival reces... more Controversy exists in the literature between the role of orthodontic treatment and gingival recession. Whilst movement of teeth outside the alveolar bone has been reported as a risk factor for gingival recession, others have found no such association. The Angle Society of Europe devoted a study day to explore the evidence surrounding these controversies. The aim of the day was for a panel of experts to evaluate the current evidence base in relation to either the beneficial or detrimental effects of orthodontic treatment on the gingival tissue. There remains a relatively weak evidence base for the role of orthodontic treatment and gingival recession and thus a need to undertake a risk assessment and appropriate consent prior to the commencement of treatment. In further prospective, well designed trials are needed.

European journal of paediatric dentistry : official journal of European Academy of Paediatric Dentistry, Dec 1, 2021

Aim To investigate if treatment outcome in patients with Class II division 1 malocclusion treated... more Aim To investigate if treatment outcome in patients with Class II division 1 malocclusion treated by a variety of approaches is affected by masticatory muscle capacity. Materials and methods Seventy-four children with Class II division 1 malocclusion were included in the present study. These were divided into 54 children (10.4 ± 1.6 years of age) treated with fixed appliances including headgear and/or Class II intermaxillary elastics, 12 children (9.9 ± 1.9 years of age) treated with functional appliances and 8 children treated with fixed appliances and other means of treatment. Ultrasonographic masseter muscle thickness measurements were taken before treatment, while lateral cephalograms were taken before and after treatment. Statistics: Multivariate linear regression analysis was used to assess the association between masseter muscle thickness and treatment outcomes, as well as the gonial angle and treatment outcomes. Results All children showed dentoalveolar sagittal improvement during treatment. In children treated with fixed appliances and headgear and/or intermaxillary elastics, no association was found between pre-treatment masseter muscle thickness or the gonial angle and treatment outcomes. Children treated with functional appliances however showed a negative association between pretreatment masseter muscle thickness and mandibular first molar mesialisation and maxillary molar distalisation during the functional phase of treatment. A positive association was also found between the pre-treatment gonial angle and maxillary incisor retroclination and mandibular incisor proclination during the functional phase of treatment. These associations were however not maintained at the end of the two-phase treatment even in this group. Conclusions In children with Class II division 1 malocclusion treated by means other than functional appliances, treatment outcome is not associated with masseter thickness. This may be the case since the application of intermaxillary forces and torque application may offset the functional component in tooth movement. Outcomes following functional appliance treatment may be partly determined by the masticatory muscles. During functional treatment, children with a weaker masticatory system show greater dentoalveolar compensation. This is however not maintained during the second phase of fixed appliance treatment.

Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie, 2002

The aim of this study was to elucidate the influence of reduced masticatory muscle function on th... more The aim of this study was to elucidate the influence of reduced masticatory muscle function on the transversal dimensions of the premaxilla, maxilla (including the dental arch) and the calvaria in the growing rat. MATERIAL AND METHODS: 38 growing male albino rats were used. 14 animals were killed at the beginning of the experiment to provide baseline values (Young Group). The remaining animals were randomly divided into two equal groups; one received the ordinary diet in hard pellet form (Hard Diet Group), and the other a soft diet (Soft Diet Group). The experimental period started when the rats were 28 days old and had a duration of 28 days. 3D measurements of the dentofacial skeleton were performed on dry skulls with a Reflex microscope. RESULTS: No inter-group differences were found in mean body weight and overall length of the cranium. The dental arch was found to be narrower in the third molar region in the Soft Diet Group, possibly due to less growth in the midpalatal suture and/or to reduced occlusal loading. This may be due to the first and second molars having been in occlusion at the beginning of the experimental period, while the third molars were not. Furthermore, the premaxilla and the frontal bones at the most lateral part of the temporal crest were narrower in the Soft Diet Group, these regions being areas of masticatory muscle attachment.

European journal of paediatric dentistry, 2019

Patients with myotonic dystrophy (MD), a neuromuscular multisystem disease characterised by progr... more Patients with myotonic dystrophy (MD), a neuromuscular multisystem disease characterised by progressive muscular weakness, often present with an anterior open bite associated with excessive facial vertical development. These aberrations in vertical craniofacial growth may be due to the reduced function of the masticatory muscles and the lowered position of the tongue. Well-planned and executed treatment of these patients, with orthodontics and orthognathic surgery, can provide satisfactory results. The long-term stability of these treatment results however remains undocumented. This paper describes a case of severe anterior open bite in a patient with MD treated with orthodontics and orthognathic surgery, with an acceptable post-treatment result. Long-term follow-up however revealed a highly unstable outcome. Reasons for this include the continued overeruption of posterior teeth due to the weakened masticatory musculature, mandibular posture, or problems with TMJ adaptation and remo...

Reviewers 2015

European Journal of Oral Sciences, 2015

Journal of Oral Rehabilitation, 2017

Myotonic muscle dystrophy is a systemic disease with early engagement of the facial muscles. Our ... more Myotonic muscle dystrophy is a systemic disease with early engagement of the facial muscles. Our aim was to study dysfunction of the temporomandibular system in patients with 'classic' dystrophia myotonica (DM1) and compare it with TMD patients and healthy controls. The study included 27 referred patients with DM1, 18 women and 9 men, aged 30-62 years, and two matched control groups: patients with temporomandibular disorders symptoms (TMD) and healthy controls, both groups were consecutive patients. The patients answered questions regarding facial pain, jaw function and dysfunction. A clinical examination of the temporomandibular system including the occlusion was performed, and the maximum bite force and finger forces were measured. Among the DM1 patients, 33 % reported difficulty biting off, and 22 % had difficulty chewing, avoiding foods like meat and raw vegetables, and 37 % of the DM1 patients scored their pain and discomfort as moderate to fairly severe. Their main complaints were TMJ clicking and locking, difficulty opening wide, and tiredness. They had more clinical signs of dysfunction compared with the controls (p < .001), but no statistically significant difference to the TMD patients. The maximum bite force in DM1 patients was impaired compared to both the TMD patients and the controls (p < .001). Significantly more occlusal interferences were found in DM1 patients, and were associated with chewing difficulties (p < .001). In conclusion, patients suffering from DM1 had an increased prevalence of TMD symptoms, reported impaired chewing function and had a decreased maximum bite force.

The influence of altered functional loading and posterior bite-blocks on the periodontal ligament space and alveolar bone thickness in rats

Acta odontologica Scandinavica, Jan 27, 2016

Posterior bite-blocks are resin-based structures elevating the occlusion and creating intrusive f... more Posterior bite-blocks are resin-based structures elevating the occlusion and creating intrusive force on the posterior teeth. Bite-blocks were applied to the molars of growing rats and a hard and soft diet was used to create altered functional masticatory forces. The aim of the present investigation was to study the effect of this appliance on the periodontal ligament space and alveolar bone thickness when combined with altered masticatory forces. Fifty-two four-week-old rats were divided into two groups, hard and soft diet. Two weeks later, half of them received a bite-block appliance, creating four groups: control hard (CH), control soft (CS), bite-block hard (BH) and bite-block soft (BS). All were sacrificed at age of 10 weeks. Their heads were scanned by micro-CT and periodontal ligament space (PDL) width, cross-sectional alveolar socket surface and alveolar bone thickness were measured. Analysis of variance (ANOVA) was used to compare the groups. The PDL was 9.2% thinner in the...

Masticatory muscle function and craniofacial morphology. An experimental study in the growing rat fed a soft diet

Swedish dental journal. Supplement, 1986

The present series of investigations was performed in order to study the relationship between mas... more The present series of investigations was performed in order to study the relationship between masticatory function and craniofacial morphology, and to elucidate the mechanism underlying possible functional changes in the craniofacial growth in rats fed a soft diet. The experimental model chosen was comprised of young rats with altered masticatory function, induced by changing the consistency of the diet. Possible influences on the craniofacial growth were studied longitudinally by x-ray cephalometry, and the bone graft reaction in the facial skeletal regions of rats was assessed in sutures and cortical bone by vital stain, micro-radiography and routine histology. The attrition and eruption rate of the rat incisors were measured "clinically", and the effect of an increased attrition was tested cephalometrically, to see whether it influences the craniofacial growth. In order to evaluate the forces developed by the masticatory muscles the active tetanic tension was measured a...

Objectives-The dental follicle plays an important role in tooth eruption by providing key regulat... more Objectives-The dental follicle plays an important role in tooth eruption by providing key regulators of osteogenesis and bone resorption. Patients with cleidocranial dysplasia (CCD) exhibit delayed tooth eruption in combination with increased bone density in the maxilla and mandible, suggesting disturbances in bone remodeling. The aim of this study was to determine the expression of genes relevant for tooth eruption and bone remodeling in the dental follicles of patients with CCD and normal subjects. Material and Methods-Thirteen dental follicles were isolated from five unrelated patients with CCD, and fourteen dental follicles were obtained from 10 healthy individuals. All teeth were in the intraosseous phase of eruption. The expression of RANK, RANKL, OPG, and CSF-1 was determined by quantitative RT-PCR. Results-In patients with CCD, the mRNA levels of RANK, OPG, and CSF-1 were significantly elevated compared with the control group. Accordingly, the ratios of RANKL/OPG and RANKL/RANK mRNAs were significantly decreased in patients with CCD. Conclusion-The observed alterations in the expression and ratios of the aforementioned factors in the dental follicle of CCD individuals suggest a disturbed paracrine signaling for bone remodeling that could be responsible for the impaired tooth eruption seen in these patients.

Laboratory Animals, 2002

Normal macroscopic and roentgenographic features of the skull of the ferret ( Mustela putorius fu... more Normal macroscopic and roentgenographic features of the skull of the ferret ( Mustela putorius furo) were examined and described. Data were based on a sample of 100 (50 male and 50 female) adult ferrets of known body weight and age. The skull was described macroscopically according to six standard views, i.e. dorsal, lateral, ventral, caudal, cranial and midsagittal. The mandible was described separately. The roentgenographic characteristics of the ferret skull were demonstrated only in lateral and dorsoventral projections. Furthermore, the skull length and width as well as the minimum frontal width were measured, and skull indices were derived from relevant measurements. Sexual dimorphism was examined both morphologically and craniometrically. Besides the common features of a carnivore skull, the ferret skull is relatively elongated and flat with a short facial region. The skulls of adult male ferrets are about 17% longer and 22% wider than those of the females. Significant sexual ...

Overeruption of periodontally affected unopposed molars in adult rats

Journal of Periodontal Research, 2010

In clinical practice, anterior teeth with periodontal disease exhibiting signs of overeruption ar... more In clinical practice, anterior teeth with periodontal disease exhibiting signs of overeruption are occasionally encountered. However, the influence of periodontitis on unopposed teeth needs to be further elucidated. This study investigated, in rats, the overeruption pattern of unopposed mandibular molars with experimentally induced periodontitis. Sixty adult male rats were divided equally into four groups. In two groups, periodontitis was induced by a silk thread placed around the cervix of the right mandibular molar. In two groups with and without experimentally induced periodontitis, the crowns of the right maxillary molars were reduced occlusally by grinding to simulate unopposed teeth. After 4 wk, the animals were killed and scanned using micro-computed tomography to measure the vertical position of molars and the buccal and lingual alveolar bone levels. There were no significant differences in the overeruption of opposed molars with and without periodontitis. However, the alveolar bone level of opposed molars with periodontitis was lower than that of healthy molars. Healthy unopposed molars were extruded when compared to molars with an antagonist. The alveolar bone level of healthy unopposed molars was not influenced by molar overeruption. Unopposed molars with periodontitis exhibited significantly larger extrusion than healthy unopposed molars. The lingual alveolar bone level of unopposed molars with periodontitis was lower than that of other healthy and periodontally affected teeth. The loss of antagonist causes overeruption of the unopposed tooth, which becomes more prominent in the presence of periodontitis.

Comparison of the prevalence, severity and possible causes of occlusal tooth wear in two young adult populations

Journal of Oral Rehabilitation, 1993

Most reports of the prevalence and severity of tooth wear in contemporary Western populations cla... more Most reports of the prevalence and severity of tooth wear in contemporary Western populations claim that advanced wear in uncommon by comparison with certain non-Western populations. Differing methods of wear evaluation in the various studies, however, preclude accurate comparisons from being made. This study records mean total and segmental wear indices obtained from the casts of a selected Swedish patient population sample, and age- and sex-matched Saudi high-wear and random samples. The wear experience of the Saudi random sample compared favourably with that of the Swedish selected one, while the wear of the Saudi high-wear sample was significantly higher than that of the Swedish sample (P < 0.01). The findings from a questionnaire revealed certain significant correlations between aetiological factors and wear, most notably, the relatively greater presence of bruxism (P < 0.01), absence of biting habits and minimal cola consumption (P < 0.01) in the Swedish sample. Harsh environmental and climatic conditions probably account for the Saudi experience of high wear.

The European Journal of Orthodontics, 2009

Dentofacial growth in orthodontically treated and untreated children with juvenile chronic arthritis (JCA). A comparison with Angle Class II division 1 subjects

The European Journal of Orthodontics, 1995

The changes in craniofacial growth and development of dental occlusion were studied in children w... more The changes in craniofacial growth and development of dental occlusion were studied in children with juvenile chronic arthritis (JCA), and treatment with functional orthodontic appliances (activators) was tested in both JCA and healthy children with distal occlusion. Fifteen JCA children with Angle Class I occlusion and 15 JCA children with Angle Class II malocclusion were followed longitudinally and compared with 23 healthy children with Angle Class II malocclusion. The facial growth of the JCA children without need of orthodontic treatment mainly followed the normal pattern while the JCA children with Angle Class II malocclusion had a deviating facial morphology, which became more abnormal during growth. During the orthodontic treatment period a slight improvement was seen in mandibular positions in the sagittal and vertical planes in both treated groups, but the changes were more marked in the healthy children. None of the treated groups attained completely normal facial morphology, but in most children the occlusion improved and could be classified as normal. The morphology achieved by treatment largely remained the same during the follow-up period and relapse was seen only in a few children. JCA children with minor skeletal discrepancies can be satisfactorily treated during growth with functional orthodontic appliances, possibly in combination with fixed appliances. Even if skeletal changes in response to orthodontic treatment are rather limited, these changes combined with the improvement in dental occlusion obtained through treatment may result in better dentofacial aesthetics. Furthermore, jaw functions are likely to improve which also might benefit the patient from a psychosocial point of view.

European Journal of Oral Sciences, 2005

Bone, 2006

The association between skeletal bone mineral density (BMD) and mandibular alveolar bone mass has... more The association between skeletal bone mineral density (BMD) and mandibular alveolar bone mass has been reported to be rather weak, probably due to local functional factors. Many new investigations are therefore focused on assessing the mandibular bone structure. No long-term structural alterations have been reported in human mandibular bone with the exception of alveolar crest changes related to periodontal disease. The aim of this prospective study was to investigate dentate women to see if possible alterations in the radiographic characteristics of the mandibular alveolar bone are related to changes in BMD. The BMD of 131 women (initial age 22-75 years) was determined in the distal forearm with dual energy X-ray absorptiometry on two occasions separated by an interval of 5 years. Mandibular alveolar bone mass (MABM) was assessed both by the optical density and by the grey-level value on digitized, calibrated, periapical radiographs. The radiographic alveolar bone structure was evaluated with a visual index [Lindh C, Petersson A, Rohlin M. Assessment of the trabecular pattern before endosseous implant treatment: diagnostic outcome of periapical radiography in the mandible. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1996;82:335-43. [16]] and digitally by the alveolar bone texture. MABM decreased significantly during the 5-year period. Changes in MABM, evaluated by the mean greylevel value of a bone segment between the premolars, were correlated to changes in skeletal BMD (r = 0.33, P b 0.001). Changes in MABM, evaluated by the optical density, did not correlate to changes in skeletal BMD. The overall trabecular pattern did not change during the study period, but small changes in the bone texture were measured. The changes in the bone texture were correlated with BMD change (r = 0.39, P b 0.001). We conclude that changes in the mandibular alveolar bone do reflect changes in the skeletal BMD, and these may be estimated on periapical radiographs by changes in their grey-level value and their texture.

Archives of Oral Biology, 1988

The forces developed by the masseter muscle and the diet-related changes were studied in situ. Th... more The forces developed by the masseter muscle and the diet-related changes were studied in situ. The active tetanic tension was measured indirectly by recording the forces applied to the mandible in four different predetermined interincisal distances. The highest tension developed in all the experimental groups was with an .mterincisal distance of 11 mm. The tetanic tension was significantly lower in rats fed a soft diet than in t:hose fed a normal diet. This difference might be due to the smaller muscle fibres in rats with decreased functional demand. The changes in the masticatory muscles may influence the tension applied to the facial skeleton and cause the alteration in the craniofacial growth previously found in rats fed a soft diet.

American Journal of Orthodontics and Dentofacial Orthopedics, 2006

The aim of this study was to quantify the influence of reduced masticatory muscle function on sut... more The aim of this study was to quantify the influence of reduced masticatory muscle function on sutural bone apposition in the growing rat. Methods: Twenty-six growing male albino rats were randomly divided into 2 equal groups; 1 (hard-diet group) received the ordinary diet of hard pellets, and the other (soft-diet group) received the powdered form of the ordinary diet mixed with water. The experimental period started when the rats were 4 weeks old and lasted 42 days. At days 0, 14, and 28, calcein was injected into all animals. At the end of the experiment, the animals were killed, and the heads were taken for preparation of undecalcified frontal sections, 120 m thick. Three representative homologous sections for each animal in both groups were selected and studied under a fluorescence microscope. The level of bone apposition at the time of calcein injection was marked with separate fluorescing lines. Because the lines from the first injection could not be seen in all areas, bone apposition in the internasal, naso-premaxillary, and inter-premaxillary sutures was quantified from day 14 to the end of the experimental period, by using an image analysis software. Results: In both groups, greater bone apposition was found between days 14 and 28 than between days 28 and 42 of the experimental period. Less bone apposition was found in the soft-diet group than in the hard-diet group in all sutures studied. Conclusions: The findings suggest that bone apposition in the studied facial sutures in the anterior facial skeleton of the growing rat is significantly affected by reduced masticatory function.

Craniofacial bone remodeling in growing rats fed a low-calcium and vitamin-D-deficient diet and the influence of masticatory muscle function

Acta Odontologica Scandinavica, 1996

Fifty-two male growing rats were randomly divided into three groups. The first group (n = 18) rec... more Fifty-two male growing rats were randomly divided into three groups. The first group (n = 18) received a hard deficient diet, and the second (n = 18) a soft deficient diet. The control group (n = 16) was fed the normal hard diet. At the beginning and in the middle of the 28-day experimental period oxytetracycline was injected. Two representative coronal sections of the snout and the corresponding contact microradiographs were analyzed. The bone mass of the premaxillary and nasal bones seemed to be less in the two deficient diet groups than in the normal one, due to an increased endosteal bone resorption and decreased bone formation. No difference in the bone apposition rate and pattern could be seen between the deficient hard and soft diet groups, except in the dorsal part of the premaxilla, where the bone formed in the first half of the experiment was markedly more resorbed in the deficient soft diet group during the remaining period than in the deficient hard diet group. The morphology of the sutures was influenced by the altered function, since the sutural space became narrower, and premature obliterations of the internasal suture were observed in the deficient soft diet group. In conclusion, poor bone quality was observed in the skull of rats fed a low-calcium and vitamin-D-deficient diet, with less bone mass than in normal conditions. Masticatory function was a significant factor influencing bone remodeling and sutural growth even in situations in which a metabolic bone disturbance exists.

The effects of myotonic dystrophy and Duchenne muscular dystrophy on the orofacial muscles and dentofacial morphology

Acta Odontologica Scandinavica, 1998

This article takes a closer view of two of the less rare myopathies, myotonic dystrophy (MyD) and... more This article takes a closer view of two of the less rare myopathies, myotonic dystrophy (MyD) and Duchenne muscular dystrophy (DMD). A high prevalence of malocclusions was found among the patients affected by these diseases. The development of the malocclusions in MyD patients seems to be strongly related to the vertical aberration of their craniofacial growth due to the involvement of the masticator, muscles in association with the possibly less affected suprahyoid musculature. Thus, a new situation is established around the teeth transversely. The lowered tongue is not in a position to counterbalance the forces developed during the lowering of the mandible by the stretched facial musculature. This may affect the teeth transversely, decreasing the width of the palate and causing posterior crossbite. The lowered position of the mandible, in combination with the decreased biting forces, may permit an overeruption of the posterior teeth, with increased palatal vault height and development of anterior open bite. The development of the malocclusions in DMD patients also seems to be strongly related to the involvement of the orofacial muscles by the disease. However, the posterior crossbite is not developed owing to the narrow maxillary arch, as is the case in MyD patients. On the contrary, the posterior crossbite in DMD is due to the transversal expansion of the mandibular arch, possibly because of the decreased tonus of the masseter muscle near the molars, in combination with the enlarged hypotonic tongue and the predominance of the less affected orbicularis oris muscle.