Data collection on bone density of mandibular alveolar bone on a Hounsfield scale of the dental apex of the cranial root of the first inferior molar in dogs using computed tomography at FMVZ-UNESP

The head is the most important and specialized region in the body because it contains a range of specialized organs and, because it has interconnections between specialized organs, there is a great overlap of images. Thus, computed tomography (CT) helps in diagnosing diseases in this region, such as oral conditions, as they provide millimetric slices or cuts and demonstrate the relationship between the various anatomical structures involved, in volume and depth. Within dentistry, CT helps in the identification of pathological processes such as infection, tumors, visualization of embedded teeth and bone bed. This study aimed to assess the density of the mandibular alveolar bone at a determined point to later predict how periodontal disease is involved in bone resorption. For this, we performed a blind retrospective study (n = 124) of the CT scan files of dog skulls at FMVZ-UNESP in order to determine the density of the jaw bone using a Hounsfield scale, in the region of the dental apex of the cranial root of the first molar tooth in dogs. The results obtained were evaluated using mean and standard deviation (27.28 +/- 9.53 HU) in order to predict the normal density of the mandibular alveolar bone in the studied region. Thus, this data analysis allows a more concise evaluation of bone resorption of mandibular alveolar bone and, therefore, provides an adequate surgical planning in cases of osteosynthesis given mainly by the presence of installed periodontal disease.

Determinação do tempo de vida de restaurações totalmente cerâmicas (y-tzp/porcelana) com incidência da carga em diferentes regiões de contato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efectos de los aparatos propulsores mandibulares fijos en la articulación temporomandibular

Fixed mandibular propulsion appliances are an alternative for the treatment of Class II malocclusion in individuals with mandibular deficiency. Since they are fixed appliances, said devices keep the mandible in an anterior-forced position during rest and during all mandibular functions. When a propulsive appliance is used, the lower jaw is displaced forward and downward. This movement leads to a new position of the condyle, which can, ultimately affect the normal functioning of the temporomandibular joint (TMJ). The aim of this paper was to review effects of fixed mandibular propulsive appliance on TMJ. Inclusion criteria considered studies on animals or humans using TMJ radiography, computed tomography, and magnetic resonance imaging. Studies confirm a favorable relation between condyle and glenoid fossa following treatment with fixed mandibular propulsion appliances.

Aparelho Herbst x osteotomia sagital mandibular bilateral no tratamento do padrão II, classe II, divisão 1 em adultos: relato de casos

Two treatment options are available for adult patients with skeletal Class II malocclusion caused by mandibular deficiency: combined mandibular advancement surgery and orthodontic treatment or mandibular advancement appliance. This study aimed to analyze the effects of two therapeutic modalities of Class II malocclusion treatment with mandibular deficiency. Two distinct individuals with Class II malocclusion division 1 and mandibular deficiency were treated after growth spurt. The first individual used the Herbst appliance as a therapeutic option and the second individual was treated with bilateral sagittal osteotomy. The cephalometric, occlusion and face results were evaluated for both individuals. Correction of Class II malocclusion was observed on both Herbst and surgery patients resulting on a normal occlusal relationship with normal overjet and overbite. Therefore it was concluded that Herbst appliance can be used to treat borderline skeletal Class II in adult patients.

Análise tomográfica da articulação temporomandibular no tratamento com Herbst em adulto jovem

Class II malocclusion features a high prevalence in Brazil, being considered as a routine in orthodontic clinics. A number of appliances are shown in the literature in order to correct Class II malocclusion with mandibular retrusion. Herbst´s fixed functional appliance, idealized by Emil Herbst (1905) and reintroduced, in the 1980´s, by Hans Pancherz is highlighted for maintaining the mandible continuously advanced, showing a shorter active treament time, an immediate esthetic impact on the facial profile, as well as requiring no patient´s commitment. Recent researches indicate the use of this appliance in individuals after pubertal growth surge. The aim of the present study is to show the orthodontics practitioner the option to use this appliance so as to treat Class II in individuals after the growth surge, obtaining satisfactory outcomes and further Class II correction.

Estabilidade sagital da condiloplastia associada à cirurgia ortognática para o tratamento do osteocondroma mandibular

The aim of this study was to evaluate the stability of the conservative condylectomy technique and articular disc repositioning as the surgical treatment approach for management of mandibular condylar osteochondroma, with appropriate Orthognathic surgery. Fifteen patients (12 females and 3 males), average age of 32.3 years (range, 13 to 56 years), with unilateral active osteochondroma of the mandibular condyle were analyzed. All patients underwent conservative condylectomy, recontouring of the remaining condylar neck stump and articular disc repositioned and indicated orthognatic surgical procedures. Average post surgical follow-up was 19 months. Each patient's lateral cephalograms were traced at 3 intervals (presurgery, immediate post surgery and long-term follow-up). Immediate after surgery the oclusal plane angle decreased -2.8 ± 4.5o, the maxillomandibular complex rotated counter-clockwise with advancement at menton 5.3 ± 5.6 mm, pogonion 5.0 ± 5.1 mm, B point 3.4 ± 4.2 mm and A point 1.0 ± 1.5 mm. The long-term follow-up showed significant changes in overbite (-0.6 ± 0.5 mm) and SNGoMe (0,93° ± 1,53°). Horizontally and vertically small instabilities occurred in Me (-1.21 ± 1.94 mm) and PNS (-1.48 ± 1.67 mm) respectively. The treatment protocol studied produced counterclockwise rotation and maxillofacial mandibular advancement. The long-term follow-up showed solid dental and skeletal stability with horizontal instability of Me and PNS in the vertical direction.

Influencia dos hábitos de sucção na manifestação de dor temporo-mandibular: revisão sistemática

Objective: To assess the attitudes and knowledge about hepatitis by scholars and dental practitioners from Recife and its metropolitan region. Method: The research protocol was submitted and approved by the Ethics and Human Research Committee of the Federal University of Pernambuco. There were included 230 undergraduate students in dentistry and 104 dentists who exercise their professional activity in Recife and its Metropolitan Region. They signed a consent form and answered a questionnaire, the evaluative instrument, with objective questions about biosafety, transmission of hepatitis and sexually transmitted diseases. Results: About the types of hepatitis 133 (57.8%) students and 61 (58.7%) professionals claimed to know the types A, B and C. Concerning transmission 31 (13.5%) students and 25 (24.0%) professionals said that the main route of transmission were sexual and bloodstream respectively. Relating to imunization 221 (96.1%) students and 99 (95.2%) professionals reported that have been vaccinated against hepatitis B, however, only 126 (54.8%) students and 55 (52.9%) professionals have followed the immunization’s schema. Regarding the cleaning of the office equipment, 18.7% of the students replied that they do not know who does it. 56.7% of professionals said that it was performed with alcohol 70 ° GL.Conclusions: The findings indicate that there is a concern for biosafety but the knowledge about the forms of hepatitis transmission and biosecurity measures need to be better settled.

Avaliação radiográficada fusão das corticias lateral e medial do ramo mandibular: estudo em mandíbulas secas

Purpose: to radiographically evaluate the distance between mandibular lingula and the exact spot where buccal and lingual cortical bone plates merge in the mandibular ramus. Materials and Methods: 54 dry mandibles, divided into 3 subgroups (SG1: dentate, SG2: partially dentate and SG3: edentulous) were used in this study. Lingula position was marked with a metallic sphere and radiographs were taken. The distance between mandibular notch and lingula (I/L) and the distance between mandibular lingula and cortical bone plates fusion (L/FC) were measured. Statistical analysis was applied to the values obtained. Results: mean values for L/FC were 8,18mm, 7,30mm and 8,98mm for SG1, SG2 e SG3 respectively. Moreover, mean values for I/L were 14,02mm, 13,90mm and 12,34mm for SG1, SG 2 and SG3 respectively. The results also showed that cortical bone plates fusion took place in half I/L distance in 28,57% of the mandibles in SG1, in 46,67% of the mandibles in SG2 and in 9,09% of the pieces in SG3. Conclusions: there were no statistically significant differences in the height where cortical bone plates took place in all 3 subgroups. In SG3, the correlation between the mean value for L/FC and the mean value for I/L suggests a reduction in bone density and bone mass, which can correlate to the evaluation of older mandibles in this subgroup.

Uso de hialuronidato de sódio para tratamento de deslocamento anterior de disco articular com travamento bucal

Temporomandibular joint disorders causing limitation of mouth opening and pain may be related to the restriction of slipping or forward displacement of the mandibular condyle. Temporomandibluar arthrocentesis is the lavage of the joint and is regarded as a simple method that produces good results in patients with these symptoms. This article reports a case of disc displacement and closed lock in a patient who reported limited mouth opening and pain as the main symptoms. The treatment proposed was arthrocentesis and lavage, combining a corticosteroid with a sodium hyaluronate solution. It is concluded that arthrocentesis is a simple, efficient and barely invasive method for particular types of temporomandibular joint disorders and should be considered before opting for more invasive surgical procedures.

Frequência de ressonância e sondagem peri-implantar em implantes curtos sob carga imediata com prótese total fixa em cantiléver na arcada mandibular: acompanhamento de um ano

This paper presents a case report with the use of short dental implants and immediate prosthesis placement. After 13 months of follow-up, peri-implant probing values are near 1.87 mm and ISQ values around 78.56.

Protocolo mandibular com implantes curtos

Jaws atrophy represents a great challenge to Implantology regarding rehabilitation of edentulous areas. This paper reports an extreme mandibular atrophy with only 9mm of height between the mental foramina. In these situations, treatment options include bone augmentation techniques, transmandibular, or short dental implants. It is well accepted that bone grafts to improve height do not have good predictability. Besides, osteogenic distraction is associated with a great patient discomfort and transmandibular implants are related with high failure rates. Also, surgical-prosthetic rehabilitations with short dental implants had been associated to good success rates. The purpose of this clinical case is to report a severe mandibular atrophy, successfully treated with four short dental implants between mental foramina for implant-supported prosthesis.

Comparison of compressive strength between three different plates for mandibular angle fractures fixation

The present study aims to compare three types of internal fixation for fractures of the mandibular angle. Mechanical testing was performed on replicas of polyurethane hemimandibles sectioned at the angle region to simulate a fracture and fixed with three different hardwares. Fixation devices enrolled on this survey included the grid plates with and without an intermediate bar and the method described by Champy and colleagues in 1978 and the sample consisted of 10 hemimandibles for each group. Vertical loadings were applied on each hemimandible and recorded after a vertical displacement of 3 and 5 mm. Statistical analysis was made by means of the variance analysis (ANOVA) and the Duncan test with a significance level of 5%. The Champy technique showed a statistically significant increased resistance when compared to the grid plates after vertical displacements of 3 and 5 mm. The results of this survey suggest that the Champy technique, when compared to the grid plate positioned at the middle of the mandibular bone (placement site selected for this study), is more resistant than the grid plate and that the inclusion or not of an intermediate bar to the grid plates does not improve its resistance after linear vertical loadings.

Treatment of Atrophic Mandibular Fractures with the Pencilboneplate: Report of 2 Cases

The incidence of fractures of the atrophic edentulous mandible is still low, even with the increasing life expectancy. The reduced blood supply of the sclerotic bone, the diminished contact area between bone fragments and the patient’s systemic condition makes the treatment of those fractures a challenge for any professional. Treatment of atrophic mandibular fractures by means of miniplate osteosynthesis has not been the preferred method of fixa- tion by many authors. Yet, many surgeons have applied this type of fixation for the atrophied jaw sections. This paper reports 2 cases of fractured atrophic mandibles treated with the pencilboneplate, a monocortical 2.0 mm titanium, 8 or 10-hole hardware with reinforcement on its middle portion, highlighting important considerations of its use. The pencilboneplate appears to be a valuable option for the treatment of atrophic mandibular fractures, espe- cially by an intra-oral approach, and warrants further bio- mechanical and clinical studies.

Fractal dimension of the mandibular trabecular bone measured on digital and digitized images.

Aims: This study compared fractal dimension (FD) values on mandibular trabecular bone in digital and digitized images at different spatial and contrast resolutions. Materials and Methods: 12 radiographs of dried human mandibles were obtained using custom-fabricated hybrid image receptors composed of a periapical radiographic film and a photostimulable phosphor plate (PSP). The film/ PSP sets were disassembled, and the PSPs produced images with 600 dots per inch (dpi) and 16 bits. These images were exported as tagged image file format (TIFF), 16 and 8 bits, and 600, 300 and 150 dpi. The films were processed and digitized 3 times on a flatbed scanner, producing TIFF images with 600, 300 and 150 dpi, and 8 bits. On each image, a circular region of interest was selected on the trabecular alveolar bone, away from root apices and FD was calculated by tile counting method. Two-way ANOVA and Tukey’s test were conducted to compare the mean values of FD, according to image type and spatial resolution (α = 5%). Results: Spatial resolution was directly and inversely proportional to FD mean values and standard deviation, respectively. Spatial resolution of 150 dpi yielded significant lower mean values of FD than the resolutions of 600 and 300 dpi ( P < 0.05). A nonsignificant variability was observed for the image types ( P > 0.05). The interaction between type of image and level of spatial resolution was not signi fi cant (P > 0.05). Conclusion: Under the tested, conditions, FD values of the mandibular trabecular bone assessed either by digital or digitized images did not change. Furthermore, these values were in fluenced by lower spatial resolution but not by contrast resolution.

Treatment of severe facial asymmetry secondary to osteochondroma of the mandibular condyle: case report

Osteochondroma (OC) is the most common benign tumor of long bones. However it is rarely found in the facial skeleton, being the coronoid process and mandibular condyle the most affected sites in this region. It basically consists in bone growth covered by cartilage. The etiology is still controversial: neoplastic, developmental, reparative and traumatic origins have been discussed in literature. The treatments of these lesions include total condylectomy or local resection of the lesion. This paper aims to report a case of a patient with history of trauma and possible fracture of the mandibular condyle in childhood, which in youth developed dentofacial deformity with severe facial asymmetry. The treatment consisted of resection of lesion both with maxillary and mandibular osteotomies associated with graft from the iliac crest bone. Actually, the patient is with a favorable aesthetic, without functional deficit and absence of lesion’s recurrence.