[Upper airway's 3D analysis of patients with obstructive sleep apnea using tomographic cone beam]. / Analyse tridimensionnelle de la voie aérienne supérieure des patients atteints d'un syndrome d'apnées et d'hypopnées obstructives du sommeil par la technique du Cone Beam.

The progress of medical imaging over the last decades has led to a better understanding of the upper airway structure in sleep-disordered patients. The Obstructive Sleep Apnea Syndrome (OSA) is attributed to a functional narrowing of the upper airway, particularly of the oropharynx, during sleep. This narrowing is multifactorial. We have shown that in 60% cases, the maxilla (nasal pyramid) seems too narrow. A mandible retroposition may also play a dominant role in 30% of the cases. Both scenarios can be combined. Cone Beam Computed Tomography (CBCT) is a new medical imaging technique that permits to visualize the upper airway with less ionizing radiation than the conventional scanner. To date, only five authors have performed an upper airway's 3D analysis of sleep apnea patients with cone beam. A better understanding of the affected segment of the upper airway should help refine treatment options.

Pulp temperature increase during photo-activated disinfection (PAD) of periodontal pockets: an in vitro study.

The capacity of photo-sensitizers, used in combination with laser light to kill micro-organisms has been demonstrated in different studies. Photo-activated disinfection (PAD) has been introduced in periodontology as an aid for disinfection of periodontal pockets. The aim of this study is to verify the harm for dental vitality of the use of PAD in periodontal pockets. Root canals of 24 freshly extracted human teeth where prepared using profiles up to a size of ISO #50 and filled with thermo-conductor paste. A silicon-based false gum was made in which a periodontal pocket was created and filled with photo-sensitizer phenothiazine chloride (phenothiazine-5-ium, 3.7-bis (dimethylamino)-, chloride). The external root surface was irradiated during 60 s with a 660-nm diode laser (output power: 20 mW; power density: 0.090 W/cm(2); Energy density: 5.46 J/cm(2)) using a periodontal tip with a diameter of 1 mm and a length of 7 mm. Temperatures were recorded inside the root canal using a thermocouple. Measurements were recorded every second, starting at 10 s before lasering, during the irradiation and were continued for 150 s after the end of irradiation, and six measurements were done per tooth. An average temperature increase of 0.48 +/- 0.11 degrees C was recorded. Our results demonstrated that pulp temperature increase was lower than 3 degrees C, which is considered to be harmless for pulp injury. Regarding pulp temperature increase, the use of PAD for disinfection of periodontal pockets can be considered as a safe procedure for dental vitality.

Evaluation of dental pulp temperature rise during photo-activated decontamination (PAD) of caries: an in vitro study.

Photo-activated decontamination (PAD) has been reported in caries treatment as an aid in dentine decontamination. The aim of this study is to verify the harmlessness for pulp vitality of photo-activated decontamination (PAD) in caries treatment. Twenty freshly extracted single-rooted teeth were used. Deep class I cavities with a

[Improvement of oral rehabilitation prosthetic techniques thanks to orthodontics]. / Optimalisation des techniques prothétiques de réhabilitation orale grace à l'orthodontie: analyse d'un cas clinique.

This clinical case underlines the importance of a multidisciplinary approach, prosthetic and orthodontic, for the achievement of an oral rehabilitation treatment plan. Preliminary orthodontic treatment has significantly improved, the position of some natural teeth, which can serve or not as a prosthetic abutment. This has produced a direct prosthetic benefit by limiting tissue reduction for preparation and by giving a better biomechanical and functional context to the restoration.Thus, after an orthodontic treatment step, lasting a year and a half, using both removable appliance and fixed appliance, prosthetic rehabilitation was possible. This included a fixed prosthesis and a removable prosthesis that gave a very satisfying an esthetic result and good masticatory function.

[Traumatic injuries to primary dentition]. / Les traumatismes en denture lactéale.

Severe sequelae may result from trauma to the primary teeth. Since as many as 51% of infants under age 6 may present such lesions, it seems logical that all members of the medical team be aware of their importance and treatment. Prompt and appropriate treatment will allow, in the majority of cases, to preserve the primary teeth. This, in turn, is the safest way to allow proper growth of the maxillaries and the permanent teeth. The present article reviews the various lesions, their treatment and follow-up to bring this public health problem to the attention of all the medical profession.

Localized Piezoelectric Alveolar Decortication for Orthodontic Treatment in Adults: A Randomized Controlled Trial.

This randomized controlled trial aimed to evaluate the benefits and clinical outcomes of piezocision, which is a minimally invasive approach to corticotomy that is used in orthodontic treatments. Twenty-four adult patients presenting with mild overcrowdings were randomly allocated to either a control group that was treated with conventional orthodontics or a test group that received piezo-assisted orthodontics. The piezocisions were performed 1 wk week after the placement of the orthodontic appliances. Neither grafting material nor sutures were used. All patients were followed every 2 wk, and archwires were changed only when they were no longer active. The periods required for the completion of the overall orthodontic treatments were calculated, and the periodontal parameters were evaluated at baseline and at the end of the orthodontic treatment. Patient-centered outcomes were assessed with a visual analog scale; analgesic use following the procedures was also recorded. The patient characteristics were similar between the 2 groups. The overall treatment time was significantly reduced by 43% in the piezocision group as compared with the control group. In both groups, periodontal parameters (i.e., recession depth, pocket depth, plaque index, and papilla bleeding index) remained unchanged between the baseline and treatment completion time points. No increase in root resorption was observed in either group. Scars were observed in 50% of the patients in the piezocision group. Analgesic consumption was similar following orthodontic appliance placement and piezocision surgery. Patient satisfaction was significantly better in the piezocision group than in the control group. In these conditions, the piezocision technique seemed to be effective in accelerating orthodontic tooth movement. No gingival recessions were observed. The risk of residual scars might limit the indications for piezocision in patients with a high smile line (ClinicalTrials.gov NCT02590835).

Modified bonded bridge space maintainer.

The premature loss of primary teeth can create the need for space maintenance and restoration of function. This article presents a fixed bonded space maintainer, which allows space to be maintained with economy of dental tissues.

Acromegaly and sleep apnea: cephalometric evaluations.

Lateral teleradiography is a standard and quick examination. It has enabled us to define differences as regards to the craniofacial morphology between 20 acromegalic patients and 20 control subjects. The height of the mandibular ramus (from the posterior condyle point to the gonion point) increases significantly with the acromegalic patient and the cranial base angle (basion-superior tuberculum sellae-M point) is more extended. As acromegalic patients are more subject to sleep apnea (30% prevailing), the relationship between the amount of sleep apnea and hypopnea (AHI) in an acromegalic patient and his bone, tissue and hormone factors has been researched, in order to act on the causes of sleep apnea. It has emerged that confronting craniofacial bones and soft tissues factors enables a good prediction of the apnea and hypopnea index. Of course, we can find again the potential action of growth hormone (GH) but only in fifth place in importance order. The tongue, which increases in volume with the GH impact, is in a too short "lingual enclosure" (reduced length of the mandibular horizontal branch).

[The need of efficient chewing function in young children as prevention of dental malposition and malocclusion]. / Diversification alimentaire et développement dentaire: importance des habitudes alimentaires des jeunes enfants pour la prévention de dysmorphoses orthodontiques.

The eating behaviors (including breast-feeding, early edge to edge incisor bite and the chewing cycle) progressively induce, among children, continuous stimulations of the growth of the maxillaries and of the dento-alvéolar structures. Unfortunately, with our usual modern soft, tenderized or semi-fluid diet, there is now a failing chewing function and the stress on the growth process are often insufficient. Many dental malpositions and malocclusions result from such "functional atrophies" of the maxillaries due to an underdevelopment of the dental arches involving incisal crowdings and lateral cross-bites. The lack of progressive natural grindings of the primary teeth and the consequent lack of development of an attritional occlusion in the deciduous dentition are signs of a poorly trained mastication and a bad prognosis for the alignment of the permanent incisors.

Comparison of microleakages of photo-cured composites using three different light sources: halogen lamp, LED and argon laser: an in vitro study.

In this study, we compared the microleakage of composite fillings cured with halogen bulb, LED and argon ion laser (488 nm). Twenty-four extracted human molars were divided randomly in three groups. Six cavities were prepared on the coronal part of each tooth. Standard cavities (1.7 x 2 mm) were prepared. Cavities were acid etched, sealed with Scotch Bond 1 and filled by a hybrid composite. Cavities were exposed to one light source, thermocycled and immersed in a 2% methylene blue dye solution. Dye penetration in the leakage of cavities was recorded using a digital optical microscope. Mean values of percentage of dye penetrations in microleakages of cavities were 49.303 +/- 5.178% for cavities cured with LED, 44.486 +/- 6.075% with halogen bulb and 36.647 +/- 5.936% for those cured by argon laser. Statistically significant difference exists between cavities cured by halogen vs LED (P < 0.01), halogen vs laser (P < 0.001) and LED vs laser (P < 0.001). The lowest microleakage was observed in the cavities and composites cured with argon ion laser.

Temperature rise during photo-activated disinfection of root canals.

The aim of this study was to determine whether it is safe to use photo-activated disinfection (PAD) during root canal treatment without heating the periodontal tissues. Root canals of 30 freshly extracted single-rooted teeth were prepared using ProFiles up to size ISO 40 and then filled with photo-sensitiser: tolonium blue (1.2 mg/l). The 635 nm diode laser was used with the manufacturer's endo-tip. Samples were irradiated for 150 s (output power 100 mW, approximate energy density 106.16 J/cm(2)). Temperatures were recorded at working length on the external root surface. After 150 s of PAD irradiation, the average temperature rise was 0.16 +/- 0.08 degrees C. All values were lower than the 7 degrees C safety level for periodontal injury. It was concluded that, regarding the temperature increase, the use of PAD in root canals could be considered harmless for periodontal tissues.

[Interception in the primary dentition: mastication and neuro-occlusal rehabilitation]. / L'interception en denture temporaire: mastication et réhabilitation neuro-occlusale.

After evoking the characteristics of masticatory movements, their control and their adaptability, a review of the literature illustrates how the masticatory work and its variations can influence the dentoalveolar, as well as the maxillary growth, by adapting the morphological structures to the functional context. The conceptions of Planas, and especially his "neuro-occlusal rehabilitation", are widely explained: unilateral alternate mastication, "Planas' Functional Masticatory Angles (PFMA) and the vertical dimension, the "atrophies" of maxillary development resulting from reduced mastication, the "dominant unilateral mastication syndrome" and, of course, all the original treatments introduced by Planas. These specific orthodontic treatments can be applied as interceptive procedure as early as during the deciduous dentition. The selective occlusal grinding, implemented to reduce and balance the "PFMA", and the expansion devices using "running track plates" are described in concepts and clinical uses. Planas' Class II treatments of Class II, also using "direct occlusal bonded tracks" and several mandibular propulsion auxiliaries are explained as well as the early treatments of lateral cross-bite and the use of the "Equiplan". Mastication, the first of the functions assigned and carried out by the masticatory apparatus, is a genuine "functional matrix" able to stimulate the growth of the dental arches and of the maxillaries. When perfectly understood and applied, the "neuro-occlusal rehabilitation" according to Planas allows to restore a functional balance for the masticatory apparatus from an early age, and subsequently, reorientates growth to a morphological normalization.

[Non-obstructive etiology of mouth breathing]. / Etiologies non-obstructives de la respiration buccale.

Besides nose obstruction other etiological factors can be advanced to explain the development of oral respiration: malformation of the face (Binder's syndrome, Bimler's microrhinodysplasia, Apert's and Crouzon's syndrome); alterations or deviations of the tongue (Robin's syndrome, macroglossia, ankyloglossia); lip closure problems.

[Orthognathic and orthodontic consequences of mouth breathing]. / Conséquences orthognathiques et orthodontiques de la respiration buccale.

There is a large controversy about the causal relations between dento-facial deformities and mouth-breathing habits. Some postural and morphological changes during long-term adaptation to oral respiration are evoked: opening of the bite with a lowered postural position of the mandible, reduction of upper arch width, downward and backward rotation of the mandible, increased lower facial height and changes in the inclination of the lower and upper incisors. It seems that the altered postural position of the tongue and of the mandible, needed for oral ventilation, could, by soft-tissue stretching, change the growth pattern of the face.

[Orthodontic studies in mouth breathing]. / Examen orthodontique chez le respirateur buccal.

The diagnosis of dental malocclusions and skeletal deformities associated with an oral mode of breathing, requires a comprehensive orthodontic examination. The importance of dental occlusion and the skeletal morphology is stressed. Lateral sliding of the mandible when the centric occlusion shows the first contact in a cusp-to-cusp relationship; unilateral or bilateral cross-bite, due to the underdevelopment of the maxillary; the sagittal relationship of the jaws (class 1, 2 or 3); a vertical excess of the anterior facial height with postero-rotation of the mandible and open bite context. Cephalometric analysis provides a better understanding of facial architecture and allows a quantitative and qualitative appreciation of dento-skeletal dysmorphism.

[Orthodontic treatment in mouth breathing]. / Traitements orthodontiques chez le respirateur buccal.

Patients with severe alterations of the maxillary growth pattern, due to long term predominant oral respiration, primarily need orthopaedic appliances, rather than common orthodontic mechanics. In cases of maxillary transversal deficiency, rapid expansion is indicated to recover an adequate width. Such treatment improves the ability for nasal ventilation. When the maxilla is sagittally underdeveloped, a facial mask is used to protract the entire maxilla. Other ways of treatment include oral screens, partial glossectomy, myofunctional therapy and respiratory gymnastics. Finally orthodontic treatment can be planned to correct irregularities of the teeth and residual malocclusions.

[Physiology of craniofacial development]. / Physiologie de la croissance cranio-faciale.

This topic summarizes basic principles of the development and the postnatal growth of the craniofacial skeleton. The different stages involved in the progressive ossification of facial bones are exposed: the intramembranous ossification, the endochondral (intracartilagenous) ossification and the changes (remodelling and relocation) associated with periosteal and endosteal membranes.

[Orthodontic consequences of mouth-breathing]. / Conséquences orthodontiques de la respiration buccale.

Mouth breathing habits are frequently associated with orthodontic problems. In the nasal area, the lack of ventilation leads to an underdevelopment of the maxilla: lateral and sometimes anterior cross bites appear. In the buccal area, the want of maintaining the mouth opened induces a new postural position of the mandible which alters the pattern of growth of the mandible ("long face"). The functional context of the buccal praxis is also altered: low or protruded tongue, deviant swallowing, troubles of speech.... The treatment of this pathological context needs a pluridisciplinary approach where the otorhinolaryngologist, the dentist, the orthodontist and the speech pathologist have to play an important role. In the orthodontic fields, we have to carry out an orthopedic treatment (rapid maxillary expansion, facial masks,...) to normalize the growth of the maxilla before the orthodontic treatment.

[The decision to extract in orthodontics]. / La décision d'extraction en orthodontie.

Serial extractions of premolars are submitted, in the present state of the contemporary orthodontics, in opposition to the non-extraction treatments (maxillary expansion, molar distancing...). The choice depends on many parameters including the severity and the nature of the malocclusion, the age and the morphological type of the patient and also the "orthodontic philosophy" relating to the techniques used by each orthodontist. The indications and contraindications of these teeth removals are explained showing the benefits and the disadvantages in different cases. "Orthodontics extractions" of other teeth (2nd bicuspid, 1st and 2nd molar, incisor) are also discussed.