Use of platelet- and leukocyte-rich fibrin (L-PRF) as a healing agent in the postoperative period of third molar removal surgeries: a systematic review.

OBJECTIVE: The aim of this study was to analyze the effectiveness of L-PRF as a healing agent in the postoperative period of third molar extraction surgeries, as well as to investigate secondary effects, such as the reduction of pain, edema and other discomforts after the surgical intervention. MATERIALS AND METHODS: The methodology adopted consisted of carrying out a systematic review of the literature, following the model outlined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The inclusion criteria were previously established according to a systematic review protocol approved by the Prospective Register of Systematic Reviews (PROSPERO) under number CRD42023484679. In order to carry out a comprehensive search, a search in five databases was carried out, PubMed, Web of Science, Scopus, Cochrane Library and Embase. RESULTS: The search resulted in the selection of randomized controlled trials that conformed to the established criteria. Two authors independently screened the records and extracted the data. The assessment of bias was conducted according to the guidelines recommended by the Cochrane Collaboration, using version 2 of the Cochrane tool for assessing the risk of bias in randomized trials (RoB 2). CONCLUSION: This study demonstrated that L-PRF stands out by providing direct benefits to healing, vascularization and tissue regeneration. CLINICAL RELEVANCE: L-PRF plays an important role in reducing postoperative pain, edema, the incidence of alveolar osteitis and infections after third molar removal surgery, compared to patients who did not undergo the use of L-PRF.

Tomographic analysis of relationship of mandibular morphology and third molars eruption.

BACKGROUND: Lower third molars (L3M) are the last teeth to erupt in the oral cavity. Uneruption of these teeth still raises questions about its causes, in the literature (1) genetic factors, (2) dental lamina activity and, mainly, (3) insufficient growth and development of the bone bases are included. While the lack of space theory influenced by mandibular morphology and size of L3M was argued to be the main reason for L3M impaction, there is a limitation in the literature in examining such association using more accurate tomographic analysis obtained from CBCT. This work aimed to evaluate the relationship between mandibular morphology and the eruption of L3M. METHODS: In this regard, 85 Cone Beam Computed Tomographies (CBCT), with 147 L3M, were selected from the archives of the Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, obtained using an Accuitomo® Morita device and using the Dolphin Imaging 11.9 software. L3M eruption was related to linear measurements of jaw length (Co-Gn), retromolar space dimension (D2R), mesiodistal width of the L3M crowns, mandibular first molars (L1M) and mandibular canines (LC) and the angle mandibular (Ar-Go-Me). Independent samples t-test, chi-square tests and logistic regression were performed adopting a significance level of 5%. RESULTS: The average mandible length of 116.446 mm + 6.415 mm, retromolar space of 11.634 mm + 2.385 mm, mesiodistal size of the L3M of 10.054 mm + 0.941 mm, sum of the mesiodistal widths of the L1M and LC of 15.564 mm + 1.218 mm and mandibular angle of 127.23° + 6.109. There was no statistically significant association between these factors and the eruption. CONCLUSION: With the results obtained in this study, we conclude that the length and angle of the mandible, teeth size and dimension of the retromolar space are not associated with the L3M eruption.

The Prediction Capacity 3-D Software, on a 2-D Analysis, in Planning the Positioning of the Upper Lip After Maxillary Advancement.

PURPOSE: The maxillary advancement using Le Fort I osteotomy directly affects in the positioning of the upper lip (UL) and the nasolabial angle (NLA), which plays an important role in facial expression and aesthetics, because of this, the aim of this study was to evaluate the ability of Dolphin Imaging 11.8 software in predicting changes to the UL position and NLA in patients undergoing maxillary advancement. MATERIALS AND METHODS: It was a retrospective cohort study. Predictive and final tracings using pre- and postoperative Cone beam computed tomography (CBCT) of 24 patients undergoing maxillary advancement, regardless of mandibular movement, were compared. Whether the amount of advancement changes this predictability was also analyzed. The predictive and the 12-month postoperative data were evaluated using Dolphin Imaging 11.8 software and compared. Student t test was used to get the results. RESULTS: The vertical analysis of the incisal tip and cementoenamel junction of the upper central incisor (UCI) and of the UL were statistically significant (P = .001 for all). The horizontal measurements of the same variables (P = .238, P = .516, P = .930, respectively) and the NLA (P = .060) showed no statistical significance. The amount of advancement did not interfere with the variables analyzed, except for the exposure (P = .009) and inclination of the UCI (P = .010). CONCLUSION: It was concluded that the amount of maxillary advancement does not interfere with the UL prediction; the prediction capacity of the software was good for the horizontal measurements, but had a significant error index for vertical measurements.

Evaluation of bone availability for grafts in different donor sites, through computed tomography.

OBJECTIVE: To quantify the bone volume that can be safely withdrawn from 3 donor sites: (1) the mandibular symphysis, (2) the oblique mandibular line and (3) the skullcap. METHODOLOGY: For the symphysis, 200 tomographic exams were evaluated by the extension of the anterior loop of mental foramen, by the nerve, by the distance of the foramens, by the distance between the vestibular cortical and the lingual plates and by the distance between the apexes, or lower anterior teeth, and the mandibular base, using the "distance" tool of the I-CAT Vision, in the panoramic and parasagittal reformations. For the oblique line, 70 TCFC exams were analyzed retrospectively in panoramic and parasagittal reformations, evaluating the thickness of the vestibular cortical and the distance between the cortical and the mandibular canal. For the cranial bone, a hexagonal donor site located in parietal area was considered. RESULTS: The average dimensions of the bone blocks that can be safely removed from the region of the mandibular symphysis are: 32.27 mm in length, 4.87 mm in height and 4 mm in thickness, providing a volume of 628.61 mm3 available for grafting. In the oblique line, the available bone volume for grafting was 859.61 mm3. In the region of the cranial vault, multiplying the average bone thickness by the area of the hexagon, an average volume of 2,499 mm3 was obtained. CONCLUSIONS: Comparing the donor sites, the bone availability in the cranial vault is 3 times greater than in the mandibular posterior region, and at least 2 times greater than in the mandibular symphysis.

Evaluation of bone availability for grafts in different donor sites, through computed tomography

Abstract Objective To quantify the bone volume that can be safely withdrawn from 3 donor sites: (1) the mandibular symphysis, (2) the oblique mandibular line and (3) the skullcap. Methodology For the symphysis, 200 tomographic exams were evaluated by the extension of the anterior loop of mental foramen, by the nerve, by the distance of the foramens, by the distance between the vestibular cortical and the lingual plates and by the distance between the apexes, or lower anterior teeth, and the mandibular base, using the "distance" tool of the I-CAT Vision, in the panoramic and parasagittal reformations. For the oblique line, 70 TCFC exams were analyzed retrospectively in panoramic and parasagittal reformations, evaluating the thickness of the vestibular cortical and the distance between the cortical and the mandibular canal. For the cranial bone, a hexagonal donor site located in parietal area was considered. Results The average dimensions of the bone blocks that can be safely removed from the region of the mandibular symphysis are: 32.27 mm in length, 4.87 mm in height and 4 mm in thickness, providing a volume of 628.61 mm3 available for grafting. In the oblique line, the available bone volume for grafting was 859.61 mm3. In the region of the cranial vault, multiplying the average bone thickness by the area of the hexagon, an average volume of 2,499 mm3 was obtained. Conclusions Comparing the donor sites, the bone availability in the cranial vault is 3 times greater than in the mandibular posterior region, and at least 2 times greater than in the mandibular symphysis.

Immediate Removal of a Dislocated Dental Fragment from the Submandibular Space during Extraction of the Lower Third Molar: Case Report and Literature Review / Remoção Imediata de fragmento Radicular Deslocado Para o Espaço Submandibular Durante a Exodontia de Terceiro Molar Inferior. Relato de Caso e Revisão de Literatura

This paper aims to report a case of radicular displacement to the submandibular space and to review the literature seeking reports of dental displacements / fragments published in the period from 2007 to 2017 in PubMed evidencing risk factors, prevention and forms of treatment. In this article a case of displacement of dental fragments to the submandibular space with immediate removal is reported. The third molar or its roots displacement into facial spaces is a rare situation. The preoperative surgical planning is fundamental to avoid this type of complication. The association of (1) good surgical planning, (2) surgical technique utilization and adequate instruments, and (3) the surgeon experience are determining factors to avoid the occurrence of this complication. (AU).

A extração de terceiros molares é o procedimento cirúrgico mais frequente nos consultórios odontológicos. Como qualquer cirurgia, existe a possibilidade de complicações trans e pós-operatórias. O deslocamento desses dentes ou fragmento dentário para espaços faciais é raro, com frequência extremamente baixa. Este trabalho tem como objetivo relatar um caso de deslocamento radicular para o espaço submandibular e revisar a literatura buscando relatos de deslocamentos dentários/fragmentos publicados no período de 2007 a 2017 no Pubmed evidenciando fatores de risco, prevenção e formas de tratamento. Nesse artigo nós relatamos um caso de deslocamento de um fragmento radicular para o espaço submandibular, sendo este removido imediatamente. O deslocamento do terceiro molar ou de fragmentos radiculares para os espaços faciais é raro. A avaliação pré-operatória é fundamental para evitar esse tipo de complicação. A associação entre (1) planejamento cirúrgico correto, (2) utilização de técnica e materiais corretos e (3) experiência do profissional, são fatores determinantes para evitar esse tipo de complicação. (AU).

Treatment of bisphosphonate-related osteonecrosis using platelet-rich plasma: microtomographic, microscopic, and immunohistochemical analyses.

The present study aimed to investigate the use of platelet-rich plasma (PRP) on tooth extraction sites in rats treated with bisphosphonates. Thirty Albinus Wistar male rats were administered 0.035 mg/kg zoledronic acid intravenously for 8 weeks, divided into four administrations with a 2-week interval between each application, after which their upper right central incisors were extracted to induce the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). The samples were divided into the following two groups: Group 1 (G1) underwent marginal resection of BRONJ followed by the use of PRP, while Group 2 (G2) underwent resection of BRONJ but without the use of PRP. The treatment groups were evaluated after 14, 28, and 42 days. Clinical, microtomographic, microscopic, and immunohistochemical (IHC) evaluations were performed. Microtomography results revealed no significant difference between the groups (p <0.05) in any time period. Histomorphometric analysis showed increased bone formation over time for both groups (p < 0.001). G1 demonstrated a greater amount of new bone formation than G2 at 28 and 42 days (p < 0.001), with G1 presenting greater vascularization and a slightly higher VEGF expression. For both groups, RANKL/OPG expression levels were sufficient as a parameter for indicating the rate of bone remodeling in a previously treated area of osteonecrosis groups. Taken together, our findings indicated that the use of PRP improves the resolution process of BRONJ.

Treatment of bisphosphonate-related osteonecrosis using platelet-rich plasma: microtomographic, microscopic, and immunohistochemical analyses

Abstract The present study aimed to investigate the use of platelet-rich plasma (PRP) on tooth extraction sites in rats treated with bisphosphonates. Thirty Albinus Wistar male rats were administered 0.035 mg/kg zoledronic acid intravenously for 8 weeks, divided into four administrations with a 2-week interval between each application, after which their upper right central incisors were extracted to induce the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). The samples were divided into the following two groups: Group 1 (G1) underwent marginal resection of BRONJ followed by the use of PRP, while Group 2 (G2) underwent resection of BRONJ but without the use of PRP. The treatment groups were evaluated after 14, 28, and 42 days. Clinical, microtomographic, microscopic, and immunohistochemical (IHC) evaluations were performed. Microtomography results revealed no significant difference between the groups (p <0.05) in any time period. Histomorphometric analysis showed increased bone formation over time for both groups (p < 0.001). G1 demonstrated a greater amount of new bone formation than G2 at 28 and 42 days (p < 0.001), with G1 presenting greater vascularization and a slightly higher VEGF expression. For both groups, RANKL/OPG expression levels were sufficient as a parameter for indicating the rate of bone remodeling in a previously treated area of osteonecrosis groups. Taken together, our findings indicated that the use of PRP improves the resolution process of BRONJ.

Condylar positioning in orthognathic surgery: a cone beam computed tomography-based in vitro analysis of a positioning method

Aim: Orthognathic surgery aims to correct facial skeletal deformities and the correct condylar positioning is very important for stable results. The aim of the present study was to verify the occurrence of changes in the postoperative condylar positioning in artificial skulls with a skeletal Class II maxillomandibular relationship submitted to bilateral sagittal split osteotomy when the method of cephalometric data transfer was used. Methods: Ten skeletal Angle class II polyurethane skulls were used with metallic markers in the articular surfaces of the temporomandibular joint and mandibular condyles. The skulls were submitted to preoperative and postoperative cone beam computed tomography before and after the bilateral sagittal split osteotomy. To verify the condylar positioning, measurements between the distances of the markers at the temporal bones and mandibular condyles were taken in the coronal and sagittal views by the DISTANCE tool of the iCat Vision software. All measurements were obtained by one examiner in the preoperative and postoperative CBCTs, tabulated and submitted to statistical analysis by the Wilcoxon test with a level of significance of 5% (p<0,05). After 15 days of the completion of the first data collection, all measurements were redone to determine the random and systematic error by the Intraclass Correlation Coefficient. Results: With the exception of the average of the lateral-medial distance (from the measurements between the medium left markers only), the averages of the anterior-posterior distances (only in the left posterior and lateral right markers) and the vertical average (only in the central markers) showed no statistically significant differences between the preoperative and postoperative distances of the metallic markers. Conclusion: Even when using the method of cephalometric data transfer, variation of the condylar positioning occurred between the preoperative and postoperative periods. This variation occurred only in a few points of the mandibular condyles

Tomographic late evaluation of xenogeneic bone grafts in sockets of impacted third molars.

OBJECTIVE: It is necessary to preserve height and thickness of the alveolar bone to facilitate rehabilitation with osteointegratable implants or simply to maintain bone integrity after extraction. Biomaterials associated with resorbable or non-resorbable membranes, when placed in the region of the socket, may contribute to avoid this unwanted reabsorption. OBJECTIVE: The objective of this study was to evaluate the distance of the crest of alveolar ridge to the cementoenamel junction (CEJ) of the lower second molars and the bone density of the third molar socket filled with Gen-Tech®, 5 years after an exodontia using cone beam computed tomography (CBCT) to visualize the central region of the sockets, without overlapping of the buccal and lingual cortical bones. MATERIAL AND METHODS: A total of 12 individuals from an initial group of 39 patients submitted to extraction of the unruptured lower third molars and grafting of an association of inorganic bovine bone matrix, organic bovine bone matrix, collagen and bone morphogenetic proteins (BMP) (Gen-Tech®) on one side and the contralateral sockets filled only by clot, returned to control after 5 years, and were submitted to CBCT. The distance from the crest of alveolar bone to the CEJ and the bone density (BD) were measured using the i-CAT Vision Software. RESULTS: The results showed that the distance from the crest of alveolar bone to the CEJ in the control group was similar to that observed before the exodontia; in the experimental group, this distance was smaller. Considering the BD measurement, a significantly higher density was observed in the experimental group (p<0.05). CONCLUSION: Part of the biomaterial was not absorbed and allowed the stability of the evaluated parameters after 5 years, being able to be used as a bone substitute in the socket.

Tomographic late evaluation of xenogeneic bone grafts in sockets of impacted third molars

Abstract It is necessary to preserve height and thickness of the alveolar bone to facilitate rehabilitation with osteointegratable implants or simply to maintain bone integrity after extraction. Biomaterials associated with resorbable or non-resorbable membranes, when placed in the region of the socket, may contribute to avoid this unwanted reabsorption. Objective The objective of this study was to evaluate the distance of the crest of alveolar ridge to the cementoenamel junction (CEJ) of the lower second molars and the bone density of the third molar socket filled with Gen-Tech®, 5 years after an exodontia using cone beam computed tomography (CBCT) to visualize the central region of the sockets, without overlapping of the buccal and lingual cortical bones. Material and Methods A total of 12 individuals from an initial group of 39 patients submitted to extraction of the unruptured lower third molars and grafting of an association of inorganic bovine bone matrix, organic bovine bone matrix, collagen and bone morphogenetic proteins (BMP) (Gen-Tech®) on one side and the contralateral sockets filled only by clot, returned to control after 5 years, and were submitted to CBCT. The distance from the crest of alveolar bone to the CEJ and the bone density (BD) were measured using the i-CAT Vision Software. Results The results showed that the distance from the crest of alveolar bone to the CEJ in the control group was similar to that observed before the exodontia; in the experimental group, this distance was smaller. Considering the BD measurement, a significantly higher density was observed in the experimental group (p<0.05). Conclusion Part of the biomaterial was not absorbed and allowed the stability of the evaluated parameters after 5 years, being able to be used as a bone substitute in the socket.

Estudo comparativo da distorção radiográfica de implantes osseointegráveis radiografados pela técnica periapical da bissetriz / Comparative study of radiographic distortion of osseointegrated implants radiographed by bisecting-angle periapical technique

Objetivou-se verificar a ocorrência de distorção em imagens obtidas por meio de radiografias periapicais pela técnica da bissetriz. Foram utilizadas 64 radiografias periapicais, padronizadas e digitalizadas, obtidas pela técnica periapical da bissetriz de pacientes submetidos à colocação de implantes. Após a obtenção das imagens, os implantes foram mensurados pelo método de medida digital por meio do programa ImageJ, em seu comprimento e em 3 medidas transversais ao longo de seu eixo. Os dados foram tabulados e analisados estatisticamente pelo teste T pareado. Evidenciou-se distorção de ampliação nas imagens obtidas, sendo maior na arcada superior do que na inferior. As maiores ampliações foram observadas no comprimento do implante, seguido pelo diâmetro da plataforma, diâmetro do corpo e diâmetro apical, respectivamente. Concluiu-se que há distorção importante nas imagens radiográficas obtidas pela técnica periapical da bissetriz, devendo existir o devido cuidado com tal técnica, já que essa discrepância de medida afeta o planejamento, o que pode ocasionar lesão de estruturas anatômicas importantes ou gerar engano na quantidade de possíveis perdas ósseas verticais e horizontais após a instalação do implante (AU).

This study aimed to verify the occurrence of distortion in images obtained by bisecting-angle periapical radiography. We used 64 periapical radiographs, standardized and digitalized, obtained by bisecting-angle periapical technique of patients undergoing implants insertion. After images obtainment, the implants were measured by digital measurement method through ImageJ program, in length and in three cross-cuting measures along its axis. The data were organized and statistically analyzed by paired T test. It was shown distortion of magnification in obtained images, being higher in superior arcade than in inferior. The higher magnifications were observed in length of the implant, followed by the platform diameter, body diameter, and apical diameter, respectively. It was concluded that the significant distortion in the radiographic images was taken by the bisecting-angle periapical technique and there should be proper care of such technique, since this discrepancy of measure affects the planning, which can cause injury to anatomical structures or generate major mistake in the amount of possible vertical and horizontal bone loss after installation of the implant (AU).

Current considerations on bone substitutes in maxillary sinus lifting / Consideraciones actuales sobre sustitutos óseos en elevación del seno maxilar

The procedure of maxillary sinus lifting using autogenous bone was considered the reference standard choice for oral rehabilitation in cases of severe atrophic maxilla. However, it is not always a viable option, due to the limitations or morbidity caused by grafting techniques. This has led to the development of bone substitutes, which have been elaborated and improved. Choosing the best biomaterial becomes difficult due to the wide variety of bone substitutes. The aim of this article is to present some of these materials that are reported in the current scientific literature for maxillary sinus lifting.

El procedimiento de elevación del seno maxilar utilizando hueso autógeno se consideraba la opción estándar de oro para la rehabilitación oral en casos de maxilar atrófico grave. Sin embargo, no siempre es una opción viable, debido a las limitaciones o a la morbilidad causada por técnicas de injerto, lo que justifica la existencia de sustitutos óseos que han sido elaborados y mejorados. En cuanto a la amplia variedad de sustitutos óseos, se hace difícil la mejor elección de biomaterial. El objetivo de este informe es presentar una variedad de sustitutos óseos respetados en la literatura científica actual, usados en la elevación del seno maxilar.

Medication-related osteonecrosis of the jaw. Introduction of a new modified experimental model

ABSTRACT PURPOSE : To evaluate a modified experimental model for medication-related osteonecrosis of the jaw (MRONJ) through the upper right central incisor extraction followed by intravenous bisphosphonate administration. METHODS: Forty five rats underwent the upper right central incisor tooth extraction were divided in 2 groups: Group I - experimental group, 30 rats received an intravenous administration protocol of zoledronic acid 35μg/kg into the tail vein every two weeks, totalizing four administrations, during eight weeks of administration, previously the extraction, and Group II - control group, 15 rats didn't received any medication before extraction. The groups were subdivided in postoperative periods: 14/28/42 days. Clinical analysis and microtomography were performed to verify the presence of osteonecrosis. In addition, descritive histological analysis of hematoxylin-eosin stained sections was performed to evaluate the presence of osteonecrosis or necrotic foci. RESULTS: Twelve (40%) rats, from experimental group, showed clinical signs of MRONJ (p=0.005), however, all samples showed imaginologic findings like osteolysis and loss of integrity of the cellular walls (p≤0.001). Microscopic evaluation revealed osteonecrosis areas with microbial colonies and inflammatory infiltrate (p≤0.001). In the control group, all animals presented the chronology of a normal wound healing. CONCLUSIONS: The presence of medication-related osteonecrosis of the jaw after maxillary central incisor extraction in rats. This new experimental model may be considered an option for the study of MRONJ.

Investigation of a Novel PLGA/CaP Scaffold in the Healing of Tooth Extraction Sockets to Alveolar Bone Preservation in Humans.

BACKGROUND: It is expected that 40% to 60% of initial alveolar bone volume will be lost up to 6 months after tooth extraction. OsteoScaf(TM) (TRT, Toronto, ON, Canada) (poly (DL-lactide-co-glycololide/calcium phosphate [PLGA/CaP] scaffold) is a novel bone substitute material and represents a promising alternative for maintaining alveolar bone integrity in this clinical scenario. PURPOSE: Here it was hypothesized that OsteoScaf would reduce alveolar bone lost after tooth extraction in patient, acting as a clot-retention device. MATERIAL AND METHODS: A total of 10 patients (32 sockets) were included in the study, of which 16 sockets were grafted with OsteoScaf and 16 were used as control (coagulum alone). Cone beam computed tomography (CBCT) was performed both immediately following extraction and also at 120 days postoperatively, at which time biopsy samples were also harvested for histological analyses. RESULTS: Quantitative analysis of CBCT showed less bone resorption in the OsteoScaf groups, being 10.5% to 14.4% less bone lost in the center of the socket, 15.4% in the buccal region, and 12.6% in the palatal. Qualitative histological analysis showed new bone tissue in direct apposition to the scaffold - demonstrating its osteoconductive nature. CONCLUSION: OsteoScaf diminished the expected bone lost during the postextraction remodeling of the alveolar bone ridge at 120 days postextraction.

Evaluation of opening pattern and bone neoformation at median palatal suture area in patients submitted to surgically assisted rapid maxillary expansion (SARME) through cone beam computed tomography.

Surgically assisted rapid maxillary expansion (SARME) is the treatment of choice to adult patients even with severe transversal maxillary discrepancies. However, the adequate retention period to achieve the bone remodeling, thus assuring treatment stability, is controversial.Objective To evaluate the opening pattern and bone neoformation process at the midpalatal suture in patients submitted to surgically assisted (SARME) through cone beam computed tomography (CBCT).Material and Methods Fourteen patients were submitted to SARME through subtotal Le Fort I osteotomy. Both the opening pattern and the mean bone density at midpalatal suture area to evaluate bone formation were assessed pre- and post-operatively (15, 60 and 180 days) through CBCT.Results Type I opening pattern (from anterior to posterior nasal spine) occurred in 12 subjects while type II opening pattern (from anterior nasal spine to transverse palatine suture) occurred in 2 individuals. The 180-day postoperative mean (PO 180) of bone density value was 49.9% of the preoperative mean (Pre) value.Conclusions The opening pattern of midpalatal suture is more related to patients' age (23.9 years in type I and 33.5 years in type II) and surgical technique. It was not possible to observe complete bone formation at midpalatal suture area at the ending of the retention period studied (180 days).

Evaluation of opening pattern and bone neoformation at median palatal suture area in patients submitted to surgically assisted rapid maxillary expansion (SARME) through cone beam computed tomography

AbstractSurgically assisted rapid maxillary expansion (SARME) is the treatment of choice to adult patients even with severe transversal maxillary discrepancies. However, the adequate retention period to achieve the bone remodeling, thus assuring treatment stability, is controversial.Objective To evaluate the opening pattern and bone neoformation process at the midpalatal suture in patients submitted to surgically assisted (SARME) through cone beam computed tomography (CBCT).Material and Methods Fourteen patients were submitted to SARME through subtotal Le Fort I osteotomy. Both the opening pattern and the mean bone density at midpalatal suture area to evaluate bone formation were assessed pre- and post-operatively (15, 60 and 180 days) through CBCT.Results Type I opening pattern (from anterior to posterior nasal spine) occurred in 12 subjects while type II opening pattern (from anterior nasal spine to transverse palatine suture) occurred in 2 individuals. The 180-day postoperative mean (PO 180) of bone density value was 49.9% of the preoperative mean (Pre) value.Conclusions The opening pattern of midpalatal suture is more related to patients’ age (23.9 years in type I and 33.5 years in type II) and surgical technique. It was not possible to observe complete bone formation at midpalatal suture area at the ending of the retention period studied (180 days).

Lower third molar fused with a supernumerary tooth: diagnosis and treatment planning using Cone-Beam Computed Tomography / Terceiro molar inferior fusionado com um supranumerário: diagnóstico e plano de tratamento usando Tomografia Computadorizada Volumétrica

Fusion is the union of two developing dental germs, resulting in a single large dental structure. It involve two normal dental germs or the germ of a normal tooth with a germ of a supernumerary one. Supernumerary teeth are additional teeth of the normal series which may occur in any region of the dental arch, althoug they are more common in the maxilla than in the mandible. This article presents a case of fusion between a third molar and a supernumerary tooth, in which a surgical intervention was carried out, with the objective of removing the dental elements. The panoramic radiography was complemented by the Donovan´s radiographic technique, but because of the proximity of the dental element to the mandibular ramus, it was not possible to have a final fusion diagnosis. Hence, the Cone-Beam Computed Tomography which provides precise three-dimensional information, was used to determinate the fusion diagnosis and also to help in the surgical planning.

Fusão é a união de dois germes dentários em desenvolvimento, resultando numa única estrutura dentária, podendo ocorrer entre dois germes dentários normais ou entre o germe de um dente normal com um supranumerário. Dentes supranumerários são dentes adicionais à série normal e podem ocorrer em qualquer região da arcada dentária, entretanto, são mais comumente encontrados na maxila do que na mandíbula. O presente artigo ilustra um caso de fusão entre um terceiro molar mandibular e um dente supranumerário, onde foi realizada uma intervenção cirúrgica com o objetivo de remover os elementos dentários. Para complementar o diagnóstico, além da radiografia panorâmica, utilizou-se a técnica radiográfica de Donovan, mas, devido à proximidade do elemento dental com o ramo mandibular, não foi possível determinar um diagnóstico preciso de fusão. Sendo assim foi utilizada a Tomografia Computadorizada Volumétrica que fornece informações precisas e em três dimensões, possibilitando desta forma chegar ao diagnóstico de fusão e também auxiliando no planejamento cirúrgico.

Zygomaticofacial foramen location accuracy and reliability in cone-beam computed tomography.

OBJECTIVE: This study aimed to evaluate the possibility of detecting the zygomaticofacial foramen (ZFF) in cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This study evaluated ZFFs in 151 macerated skulls (302 zygomatic bones, ZBs) by physical inspection, in which the presence and diameters of the ZFFs were determined. These data were compared with the CBCT images of the skulls to determine the accuracy of CBCT in detecting ZFFs. The diameters were measured by insertion of steel wires with known thicknesses into the ZFFs. The CBCT images were acquired by an i-CAT Classic® (International Imaging Sciences, Hatfield, PA) connected to a workstation (Model ITOX Midtower Workstation; Imaging Sciences International®) with a 20-inch Eizo monitor. The images were generated in coronal, sagittal and axial slices to evaluate the best tomographic plane for ZFF visualization. RESULTS: The incidence of ZFF found by physical inspection was one foramen in 44% of ZBs (n = 133), two foramina in 28% (n = 86), three foramina in 8% (n = 24) and four foramina in 1% (n = 2). ZFF was absent in 19% (n = 57) of ZBs. The average diameter was 0.57 mm (± 0.27 mm). All foramina were observed in all tomography images. CONCLUSION: This preliminary study supports the conclusion that a CBCT scan has excellent accuracy in evaluating ZFFs.

Position of the greater palatine foramen: an anatomical study through cone beam computed tomography images.

PURPOSE: The block anesthesia of the greater palatine foramen (GPF) is largely used in minor oral surgeries, periodontics and general dentistry. Furthermore, the area of the GPF serves as a donor of soft tissue graft. So, the aim of this study was to evaluate the position and characteristics of the GPF in Brazilian patients using cone beam computed tomography (CBCT) providing anatomical information for the greater palatine nerve block anesthesia and indicate site to collect palatal donor tissue. METHODS: Fifty CBCT exams of Brazilian patients with a mean age of 35.8 years (27 male/23 female) were evaluated. All patients had erupted first, second and third upper molars. A total of 100 GPF were evaluated bilaterally. The GPFs were assessed regarding position, diameter and distances to the midline maxillary suture (MMS) and to alveolar ridge (AR). Guidelines were drawn in the CBCT axial image depicting all molar interproximal surfaces, bilaterally. The guidelines were located between first, second and third molar and in the center of the second and third, performing five guidelines in each side. These guidelines and the molars were landmarks to assess the GPF anatomic position. RESULTS: From the 100 GPF analyzed, 92 were located in the third molar region (24 male/22 female). The 92 GPF were distributed as 47 in the left side and 45 in the right side. The average GPF diameter and the distance to both the AR and the MMS were 3.1 mm; 7.9 and 15.3 mm, respectively. CONCLUSIONS: Within the limits of this study, we concluded that the in Brazilian patients studied, the GPF location was more closely related to third molar. Therefore, whenever the third molar is erupted, it could be used as landmark for successful GPN block anesthesia. Moreover, harvesting palatal mucosa graft around the third molar should be done cautiously to prevent damage to the GPF vascular-nerve complex.