Assessment of the osteogenic effect after maxillary sinus floor elevation and simultaneous implantation with or without bone grafts by analyzing trabecular bone parameters: a retrospective study

Abstract Objective: The aim of this population-based retrospective study was to compare the osteogenic effect of newly formed bone after maxillary sinus floor elevation (MSFE) and simultaneous implantation with or without bone grafts by quantitatively analyzing trabecular bone parameters. Methodology: A total of 100 patients with missing posterior maxillary teeth who required MSFE and implantation were included in this study. Patients were divided into two groups: the non-graft group (n=50) and the graft group (n=50). Radiographic parameters were measured using cone beam computed tomography (CBCT), and the quality of newly formed bone was analyzed by assessing trabecular bone parameters using CTAn (CTAnalyzer, SkyScan, Antwerp, Belgium) software. Results: In the selected regions of interest, the non-graft group showed greater bone volume/total volume (BV/TV), bone surface/total volume (BS/TV), trabecular number (Tb. N), and trabecular thickness (Tb. Th) than the graft group (p<0.001). The non-graft group showed lower trabecular separation (Tb. Sp) than the graft group (p<0.001). The incidence of perforation and bleeding was higher in the graft group than in the non-graft group (p<0.001), but infection did not significantly differ between groups (p>0.05). Compared to the graft group, the non-graft group showed lower postoperative bone height, gained bone height and apical bone height (p<0.001). Conclusion: MSFE with and without bone grafts can significantly improve bone formation. In MSFE, the use of bone grafts hinders the formation of good quality bone, whereas the absence of bone grafts can generate good bone quality and limited bone mass.

The anatomical limit and strategies for molar movement during orthodontic treatment / 口腔疾病防治

@#In many cases, tooth movement over a considerable distance is needed to meet the major goal of orthodontic treatment, which has always been to correct malocclusion and improve the facial profile in patients with skeletal malocclusion. However, tooth movement over a considerable distance also carries risks of dehiscence, fenestration, root exposure, and so forth. The reason lies in neglecting many limits for tooth movement, especially anatomical characteristics. This review focuses on structural limits for orthodontic molar movement, such as the alveolar cortex, the maxillary sinus floor, and the mandibular canal. In addition, we set the strategy in clinical orthodontics. For the alveolar cortex and the mandibular canal, orthodontists are recommended to move the root away from the cortical bone initially and formulate personalized molar movement plans according to clinical examination and cone-beam computed tomography (CBCT) and other imaging examinations. First, the molar root was controlled by torque away from the bone plate, and then, the molar movement amount and direction were controlled according to the personalized movement path. In regard to the maxillary sinus floor, light and continuous forces and scientific biomechanics are suitable for bodily tooth movement. In summary, better therapeutic efficacy and long-term stabilization could be achieved by circumventing the limits and risks caused by anatomical limitations and characteristics.

Effect of different thresholds on the accuracy of linear and volumetric analysis of native- and grafted-bone

Abstract The study aimed to evaluate the accuracy of Micro-CT in linear and volumetric measurements in native (NB) and grafted bone (GB) areas. A total of 111 biopsies of maxillary sinuses grafted with deproteinized bovine bone (DBB) in humans were evaluated. The linear measurements were performed to measure the length of the NB and GB. Furthermore, the amount of mineralized tissues at the NB and GB was performed. In the histomorphometry analysis the percentage of mineralized tissues at the NB and GB was obtained in two histological sections while the mineralized tissues were measure in the micro-CT varying the thresholds of the grayscale varying from 90-250 to 90-150 with 10 levels of variation between each one was applied. Then these data were correlated in order to check the higher r level between the histomorphometry and micro-CT thresholds intervals. The linear length of the NB was 2.44±0.91mm and 2.48±1.50mm, respectively, for micro-CT and histomorphometry (r =0.57), while the linear length of the GB was 3.63±1.66mm and 3.13±1.45mm, respectively, for micro-CT and histomorphometry (r =0.74) Histomorphometry showed 45.91±11.69% of bone in NB, and 49.57±5.59% of bone and biomaterial in the GB. The total volume of mineralized tissues that were closest to the histometric analysis were 43.75±15.39% in the NB (Threshold:90-240; r = 0.50) and 51.68±8.42% in the GB (Threshold:90-180; r =-0.028). The micro-CT analysis showed good accuracy in the linear analysis in both portions of the biopsies but for volumetric analysis just in NB.

Resumo Esse estudo tem como objetivo avaliar a acurácia da análise microtomográfica em mensurações lineares e volumétricas em osso nativo (ON) e enxertado (OE). Para isso, 111 biópsias removidas de seios maxilares de pacientes enxertados com osso bovino desproteinizado foram coletadas e avaliadas. As medidas lineares foram realizadas para medir o comprimento do ON e do OE. Além disso, foi realizada a mensuração da quantidade de tecidos mineralizados em ON e OE. Na análise histomorfométrica a porcentagem de tecidos mineralizados do ON e OE foi obtida em dois cortes histológicos enquanto os tecidos mineralizados foram medidos em microtomografias variando os thresholds da escala de cinza variando de 90-250 a 90-150 com 10 níveis de variação entre cada. Em seguida, esses dados foram correlacionados para verificar o maior nível de R entre os intervalos dos thresholds testados na análise microtomográfica em relação aos dados obtidos na histomorfometria. O comprimento linear do ON foi de 2,44±0,91mm e 2,48±1,50mm, respectivamente, para análises microtomográfica e histomorfométrica (r=0,57), enquanto o comprimento linear do OE foi de 3,63±1,66mm e 3,13±1,45mm, respectivamente, para para análises microtomográfica e histomorfométrica (r =0,74) A histomorfometria detectou 45,91±11,69% de osso na porção de ON e 49,57±5,59% de osso e biomaterial na porção de OE. O volume total de tecidos mineralizados detectados pela análise microtomográfica que apresentou valores mais próximos da análise histomorfométrica foi de 43,75±15,39% no ON (Thresholds:90-240; r = 0,50) e 51,68±8,42% no OE (Thresholds:90-180; r =- 0,028). A análise microtomográfica apresentou boa acurácia na análise linear em ambas as porções das biópsias, porém a mesma apresentou boa acurácia para análise volumétrica apenas em áreas de ON.

Expert consensus on the bone augmentation surgery for alveolar bone defects / 口腔疾病防治

@#Alveolar bone is an important anatomic basis for implant-supported denture restoration, and its different degrees of defects determine the choices of bone augmentation surgeries. Therefore, the reconstruction of alveolar bone defects is an important technology in the clinical practice of implant restoration. However, the final reconstructive effect of bone quality, bone quantity and bone morphology is affected by many factors. Clinicians need to master the standardized diagnosis and treatment principles and methods to improve the treatment effect and achieve the goal of both aesthetic and functional reconstruction of both jaws. Based on the current clinical experience of domestic experts and the relevant academic guidelines of foreign counterparts, this expert consensus systematically and comprehensively summarized the augmentation strategies of alveolar bone defects from two aspects: the classification of alveolar bone defects and the appropriate selection of bone augmentation surgeries. The following consensus are reached: alveolar bone defects can be divided into five types (Ⅰ-0, Ⅰ-Ⅰ, Ⅱ-0, Ⅱ-Ⅰ and Ⅱ-Ⅱ) according to the relationship between alveolar bone defects and the expected position of dental implants. A typeⅠ-0 bone defect is a bone defect on one side of the alveolar bone that does not exceed 50% of the expected implant length, and there is no obvious defect on the other side; guided bone regeneration with simultaneous implant implantation is preferred. Type Ⅰ-Ⅰ bone defects refer to bone defects on both sides of alveolar bone those do not exceed 50% of the expected implant length; the first choice is autologous bone block onlay grafting for bone increments with staged implant placement or transcrestal sinus floor elevation with simultaneous implant implantation. Type Ⅱ-0 bone defects show that the bone defect on one side of alveolar bone exceeds 50% of the expected implant length, and there’s no obvious defect on the other side; autologous bone block onlay grafting (thickness ≤ 4 mm) or alveolar ridge splitting (thickness > 4 mm) is preferred for bone augmentation with staged implant placement. Type Ⅱ-Ⅰ bone defects indicate that the bone plate defect on one side exceeds 50% of the expected implant length and the bone defect on the other side does not exceed 50% of the expected implant length; autologous bone block onlay grafting or tenting techniques is preferred for bone increments with staged implant implantation. Type Ⅱ-Ⅱ bone defects are bone plates on both sides of alveolar bone those exceed 50% of the expected implant length; guided bone regeneration with rigid mesh or maxillary sinus floor elevation or cortical autologous bone tenting is preferred for bone increments with staged implant implantation. This consensus will provide clinical physicians with appropriate augmentation strategies for alveolar bone defects.

Clinical guidelines for maxillary sinus floor elevation with sinus membrane lesions / 口腔疾病防治

@#Maxillary sinus membrane lesions have been broadly detected before implant surgery in the posterior maxilla region, resulting in uncertainty regarding maxillary sinus floor elevation surgery. In this context, we composed this commentary article based on the current literature and the clinical experience of our department. We discuss the common lesion types shown by CBCT including membrane pathological thickening, polyps/cystic lesions and air-liquid level in the sinus. Maxillary sinus floor elevation surgery can be conducted in patients with membrane thickening of 2-5 mm or with polyps/cysts of less than half of the sinus height (because the above symptoms have little influence on the outcome of surgery). Membrane thickening of more than 5 mm with ostium obstruction, antrochoanalpolyps, mucoceles and cysts of more than half of the sinus height should be carefully treated. Different treatments can be performed such as conducting elevation surgery while retaining the cyst, removing the cyst before surgery or removing the cyst during surgery based on the cyst type and size, inflammation, patency of the ostium, etc. Antibiotics-anti-inflammatory-aspiration, surgical debridement and oral lesions eliminations are generally used for treating post-operative sinusitis. Presurgical radiographic evaluation is the key to diagnosing and treating these membrane lesions. We highly advocate collaboration between our dentists and otolaryngologists on this issue.

The role of the membrane of the maxillary sinus in space osteogenesis under the sinus floor after elevation of the sinus floor / 口腔疾病防治

@#With the continuous development of maxillary sinus floor elevation technology, the osteogenesis mechanism of maxillary sinus floor elevation has always been a concern of scholars. The membrane of the maxillary sinus is an indispensable physiological structure in the process of space osteogenesis under the sinus floor after elevation of the sinus floor. In recent years, the role of the maxillary sinus floor mucosa in sinus floor space osteogenesis has been a research hotspot. Recent studies have found that the maxillary sinus floor membrane plays a role as a natural biological barrier membrane in the process of sinus floor space osteogenesis after maxillary sinus floor elevation; in addition, it has the ability to undergo osteogenesis. It has also been found that maxillary sinus membrane stem cells (MSMSCs) derived from the maxillary sinus floor membrane have characteristics of mesenchymal stem cells, which can differentiate into osteoblasts and participate in sinus floor space osteogenesis after maxillary sinus floor elevation. New studies have also found that small RNAs such as microRNAs, long noncoding RNAs and circular RNAs can regulate the osteogenic differentiation of MSMSCs, which may be important biological targets for promoting osteogenesis in the sinus floor space. In this paper, the relationship between the maxillary sinus floor mucosa and bone formation after maxillary sinus floor elevation, the barrier and osteogenic function of the maxillary sinus floor mucosa, the sources of osteoblasts involved in osteogenesis of the sinus floor space, and the molecular regulatory mechanisms of stem cells derived from maxillary sinus mucosa will be elucidated step by step.

Assessment of maxillary premolar region in relation to maxillary sinus floor and buccal bone plate: a cone beam computed tomography study / Evaluación de la región premolar maxilar en relación con el piso del seno maxilar y la tabla osea vestibular: estudio de tomografía computarizada de haz cónico

The maxillary sinus floor location and the buccal bone plate are factors to be considered in the long-term success with implant treatments mainly in the premolar region. the aim of this study was to establish morphometric characteristics of the buccal cortical bone (BCB) thickness of maxillary premolars and its relation to maxillary sinus floor through CBCT. In this study 350 first and second maxillary premolars were analyzed from 110 CBCT images and the buccal cortical bone (BCB) was measured in a coronal view at the major axis level of each premolar. In addition, in 200 first and second maxillary premolars CBCT images were measured the distance from premolar apex to maxillary sinus floor (MSF) in both frontal and sagittal plane. The type of relationship between the apex and MSF was classified according to Ok et al. (2014). The second premolar was observed with higher values of BCB (p<0.001). In first premolar, higher values were observed in the male sex (p>0.05). In second premolar, only significantly higher values were observed in the male sex in MA-MB-MC (p>0.05). Regarding to MSF and its relation to premolar roots, it was observed that 10 % of the sample was classified as type I, 19 % as type II, 55.5 % as type III and 15.5 % as type IV. The BCB of the upper premolar region is thicker in the apical region and decreases toward the coronal region. Almost 50 % of apex of second premolars are closely and risky related MSF (Type I and II).

La localización del piso del seno maxilar (PSM) y la tabla ósea vestibular (TOV) son factores a considerar en el éxito a largo plazo de los tratamientos de implante dental en la región premolar. El objetivo de este estudio fue establecer características morfométricas del grosor de la TOV en los premolares maxilares y su relación con el PSM a través de CBCT. Se analizaron 350 primeros y segundos premolares en 110 CBCT y la TOV fue medida en vista coronal en el eje axial mayor de cada premolar. Además en 200 primeros y segundos premolares maxilares se midió la distancia desde el ápice del diente hasta el PSM en el plano sagital y frontal. El tipo de relación entre el ápice y el PSM se clasificó según Ok et al. (2014). El Segundo premolar obtuvo los mayores valores de grosor de TOV (p<0.001). En primeros premolares se observaron valores altos en el género masculino (p>0.05). En segundos premolares solo se encontraron valores significativamente altos en el género masculino en MA-MB-MC (p>0.05). En la relación con el PSM y ápices de raíces de premolares, el 10% de la muestra se clasificó como tipo I, el 19% como tipo II, el 55,5% como tipo III y el 15.5% como tipo IV. En conclusión la TOV de la región premolares superior es más grueso en la zona apical, decreciendo hacia la zona coronal. Alrededor del 50% de los ápices de raíces de premolares maxilares están cercanas y en relación de riesgo con el PSM (tipo I y II).

Imaging classification diagnosis and maxillary sinus floor augmentation of maxillary sinus cystic lesions / 华西口腔医学杂志

Maxillary sinus cystic lesions can often be found in cone-beam computed tomography (CBCT) images. However, whether this change affects the implementation of maxillary sinus floor augmentation remains unclear. Combining the common cystic change performance of CBCT, image classification diagnosis of maxillary sinus cystic change was introduced, and the indications and surgical methods of maxillary sinus floor augmentation and postoperative radiographic changes of mucous were analyzed. This procedure may help clinicians evaluate the feasibility and methods of maxillary sinus augmentation in maxillary sinus cystic changes.

Two-stage closed sinus lift for severe bone deficiency in the posterior maxilla imrpoves long-term clinical outcomes / 南方医科大学学报

OBJECTIVE@#To evaluate the long-term clinical outcomes of two-stage closed sinus lift for the maxillary sinus with residual bone height (RBH) of 1-3 mm in the posterior maxillary.@*METHODS@#Seventy-eight patients with maxillary posterior tooth loss (1 mm≤RBH≤3 mm and alveolar ridge width ≥5 mm) were treated with two-stage closed sinus lift at the Dental Implantation Center of our hospital between March, 2012 and December, 2014. Coral hydroxyapatite powder and 148 implants were implanted. The superstructure was fixed within 6 months after the operation and the patients were followed up for 1-5 years for assessing the patients' satisfaction, postoperative response, stability and survival rates of the implant, soft tissue condition, bone height of maxillary sinus floor elevation and the marginal bone loss.@*RESULTS@#Perforation of the maxillary sinus floor occurred in 3 (3.85%) of the cases. Twenty-three (30.67%) patients complained of mild pain, and 52 (69.33%) did not experience headache or fever or reported obvious pain or swelling after the operation. The overall response to the operation was favorable. The ISQ value was 58.39±1.39 immediately after the operation, and increased significantly to 81.88±1.22 at 6 months ( < 0.05). During the healing period and the follow-up, none of the implants fell off, and the implant survival rate was 100%. The peri-implant probing depth and modified sulcus bleeding index at 1 year after sinus lifting were similar to those at 5 years after the operation ( > 0.05), but the sinus floor elevation and marginal bone resorption at the two time points differed significantly ( < 0.05).@*CONCLUSIONS@#Compared with lateral wall lifting, two-stage close lifting of the maxillary sinus floor is associated with less trauma and less discomfort, and effectively solves the problem of severe alveolar bone height deficiency in the maxillary posterior region to achieve favorable long-term clinical outcomes.

A review of rare complications of maxillary sinus floor augmentation

Maxillary sinus floor augmentation (MSFA) is an essential procedure for implant installation in the posterior maxillary area with vertical alveolar bone deficiency. For the past several decades, MSFA has been refined in terms of surgical methods along with technical progress, accumulation of clinical studies, and development of graft materials and surgical instruments. Although some complications in MSFA are inevitable in clinical situations, management of those complications in MSFA has been well established thanks to many clinicians and researchers. Nevertheless, some rare complications may arise and can result in fatal results. Therefore, clinicians should be well aware of such rare situations and complications associated with MSFA. In this review, the authors present several rare complications regarding MSFA, along with corresponding management strategies through a thorough review of the literature.

Maxillary Sinus Floor Augmentation Using Autogenous Tooth Bone Graft in Combination with Platelet-Rich Plasma for Dental Implants: Case Series

PURPOSE: To determine the benefits of autogenous tooth bone (ATB) graft in combination with platelet-rich plasma (PRP) in the rates of success and survival of dental implants placed simultaneously with maxillary sinus floor augmentation (MSFA). MATERIALS AND METHODS: Patients who visited the Department of Oral and Maxillofacial Surgery at Ulsan University Hospital from 2012 to 2014 and underwent simultaneous placement of implants with MSFA using ATB plus PRP were included in the study. Success and survival rates of the implants were evaluated based on the parameters of age and sex of the patient, site, follow-up period, residual bone height before surgery, diameter, and length of implant, sinus mucosa impairment, and postoperative complications. RESULT: A total of 23 patients and 67 implants were included in this study. The average age of the patients was 53.78±10.00 years. The average follow-up period after installation of the prosthesis was 53±5 months. The success and survival rates of the implants after placement of prosthesis were 95.52% and 97.01%, respectively. CONCLUSION: Combination of ATB and PRP showed high overall success rate, and it can be concluded that this combination is a predictable bone graft procedure for MSFA.

Maxillary sinus augmentation using biphasic calcium phosphate: dimensional stability results after 3–6 years

PURPOSE: This study was designed to observe the resorption pattern of biphasic calcium phosphate (BCP) used for maxillary sinus augmentation over a 3- to 6-year healing period, and to investigate factors affecting the resorption of BCP. METHODS: A total of 47 implants placed in 27 sinuses of 22 patients were investigated. All patients had residual bone height less than 5 mm at baseline. The modified Caldwell-Luc approach was used to elevate the maxillary sinus membrane, and the sinus cavity was filled with BCP (70% hydroxyapatite and 30% β-tricalcium phosphate). Implant placement was done simultaneously or in a staged manner. Serial radiographic analysis was performed up to 6 years postoperatively. RESULTS: During the follow-up period, no implant loss was reported. The mean reduced height of the augmented sinus (RHO) was 0.27±1.08 mm at 36 months, and 0.89±1.39 mm at 72 months postoperatively. Large amounts of graft material (P=0.021) and a long healing period (P=0.035) significantly influenced the amount of RHO. In particular, there was a significant relationship between a healing period longer than 40 months and RHO. CONCLUSIONS: BCP can achieve proper dimensional stability with minimal reduction of the graft height in a 3- to 6-year healing period after maxillary sinus augmentation. The healing period and the amount of graft material influenced the resorption of BCP.

Short-term and mid-term follow-up study of 34 cases of maxillary posterior teeth deletion treated by orthotopic implantation combined with maxillary sinus floor elevation at the same time / 中国基层医药

Objective To investigate the application value and short-term and mid-term prognosis of orthotopic implantation combined with maxillary sinus floor elevation in the treatment of patients with maxillary posterior teeth deletion at the same time.Methods A total of 68 patients with maxillary posterior teeth deletion in the Integrated Traditional Chinese and Western Medicine Hospital of Shanxi Province from June 2014 to June 2016 were selected and randomly divided into the control group(n=34)and the study group(n=34)according to the digital table.The control group was treated with dental implant technology to repair,and the study group was treated with implanted orthotopic implantation combined with maxillary sinus floor elevation at the same time.The follow-up was continued for 3-12 months after operation.The degree of postoperative pain,the incidence of complications,the satisfaction of the treatment,and the prognosis of the two groups after 12 months of operation(the exfoliation of implant and the loosening of the implant)were statistically analyzed.Results The good rate of pain in the study group was 97.06％(33/34),which was higher than that of the control group [76.47％(26/34)](P<0.05).There was no statistically significant difference in the incidence rate of complications between the study group [5.88％(2/34)]and control group[8.82％(3/34)](P>0.05).The treatment satisfaction of the study group [97.06％(33/34)] was higher than that of the control group [70.59％(24/34)](χ2 =8.758,P<0.05).The incidence rate of poor prognosis of the study group[2.94％(1/34)]was lower than that of the control group [23.53％(8/34)](χ2 =4.610,P <0.05).Conclusion Orthotopic implantation combined with maxillary sinus floor elevation in the treatment of patients with maxillary posterior teeth deletion at the same time has less postoperative pain and high treatment satisfaction.And the complications and incidence of exfoliation and loosening of implants are low after 12 months of operation.

Research progress in maxillary sinus mucosal disease associated with maxillary sinus floor lifting / 中华口腔医学杂志

Maxillary sinus augmentation is an effective procedure to gain bone height for implant placement in an atrophic posterior maxilla. But maxillary sinus diseases are prevalent in patients scheduled for sinus lift procedures. The presence of these diseases may increase the difficulties in performing the surgery and the risk of developing postoperative complications. This paper summarizes and introduces the common maxillary sinus mucosa diseases related to maxillary sinus augmentation.

Clinical evaluation of two transalveolar methods for sinus augmentation with placing 1 204 implants immediately / 中华口腔医学杂志

Objective@#To compare the clinical outcomes of posterior maxillary implant surgery when using the regular transalveolar approach or with the crestal approach-sinus (CAS-KIT), a device for maxillary sinus membrane elevation by the crestal approach using a special drilling system and hydraulic pressure.@*Methods@#In this retrospective study 887 patients during Jan 2012 to July 2015 in Hangzhou Dental Hospital with underwent either regular transalveolar approach or CAS-KIT approach for maxillary augmentation; whereas 11 patients dropped out for the reason of serious membrane perforations. Totally, 876 patients with 1 204 plants, placed immediately after transalveolar maxillary augmentation, were included in this study. The data analysis was performed by radiological measures to assess the changes in height of maxillary sinus floor after the transalveolar augmentation at different time points. In addition, the complications after surgery, failure rates, osseointegration condition and the performance of rehabilitation were evaluated as well.@*Results@#Five hundred and three patients were experienced with regular transalveolar approach, and 7 patients were drop out for the serious membrane perforations. Thus, 496 patients received 653 implants in this group; the average lifted range in maxillary sinus floor height changes was (4.08±3.45) mm. The complications were minor membrane perforations during procedure in 64 patients, postoperative maxillary sinus infection happening in 2 patients and 13 patients experienced rehabilitation failure. Three hundred and eighty-four patients had CAS-KIT approach with 4 patients dropped out. Three hundred and eighty patients get 551 implants with the mean lifted range of (8.36±4.07) mm in maxillary sinus floor height changes. Minor membrane perforations during procedure occurred in 31 people and 2 got postoperative maxillary sinus infection. The 4 year overall survival rate of 1 204 implants was 97.26%, with four implants fell off after 3 months of rehabilitation and one implant occurred after one year of rehabilitation.@*Conclusions@#The regular transalveolar sinus lift technique is easier and time saving, but the compromised lifting range in maxillary sinus floor height and the comparatively high occurrence of intraoperative membrane perforations should be concerned. Using CAS-KIT could be an alternative method to perform maxillary sinus augmentation with a reduced incidence of complications. There was no statistically difference in implant failure rates and incidence of postoperative maxillary sinus infection between two groups.

Maxillary sinus floor elevation / 口腔疾病防治

@#Maxillary sinus floor elevation is a common method to increase the bone height in posterior maxilla. Maxillary sinus floor elevation can be divided into 2 types: sinus floor elevation with lateral window approach and sinus floor elevation with trans-alveolar approach. The present article reported the anatomy, antibiotics choice, indications, grafting, growth factors, complications and the influence of tobacco on maxillary sinus floor elevation.

Study of Anatomical Relationship between Posterior Teeth and Maxillary Sinus Floor in a Subpopulation of the Brazilian Central Region Using Cone-Beam Computed Tomography - Part 2

Abstract This study evaluated the anatomical relationship between posterior teeth root apices and maxillary sinus floor (MSF) on 202 cone beam computed tomography (CBCT) exams. The distance between the root apices and the MSF, as well as the MSF thickness of the cortical bone closest to root apices and furcation regions were measured. The vertical and horizontal relationships of the MSF with the molar roots were classified into categories adapted from the criteria proposed by Kwak et al. (14). The shortest distances between MSF and the root apices were observed in the mesiobuccal root of the second molar (0.36±1.17 mm) and the palatal root of the first molar (0.45±1.10 mm) and the widest in buccal roots of the first premolars (5.47±4.43 mm). Significant differences were observed between the distance of MSF to the root apices of single-rooted first and second premolars. The cortical thickness ranged from 0.65±0.41 mm over the mesiobuccal root of the second molar to 1.28±0.42 mm over the buccal root of the first premolar. The most observed vertical and horizontal relationships were type II and 2H, respectively. The maxillary molar roots showed greater proximity to the MSF. The thickness of the MSF cortical bone closest to the apices and furcation regions was found to be similar only for premolars.

Resumo Avaliou-se a relação anatômica entre dentes posteriores e o soalho do seio maxilar (SSM) por meio da tomografia computadorizada de feixe cônico (TCFC) em 202 exames. A distância entre os ápices radiculares e o SSM, bem como a espessura do osso cortical do SSM próximo dos ápices radiculares e áreas de bifurcação foram medidas. As relações verticais e horizontais do SSM com as raízes dos molares foram classificados em categorias adaptadas a partir dos critérios propostos pelo Kwak et al. (14). A menor distância entre o SSM e os ápices dentários foi observada na raiz mesiovestibular do segundo molar (0,36±1,17 mm) e na raiz palatina do primeiro molar (0,45±1,10 mm), e a maior na raiz vestibular do primeiro pré-molar (5,47±4.43 mm). Diferenças significantes foram observadas entre a distância do SSM e os ápices dentários de primeiros e segundos pré-molares unirradiculares. A espessura da cortical óssea variou de 0,65±0,41 mm na região da raiz mesiovestibular do segundo molar a 1,28±0,42 na raiz vestibular do primeiro pré-molar. As relações vertical e horizontal mais prevalentes foram do tipo II e 2H, respectivamente. As raízes dos molares superiores apresentaram maior proximidade com o SSM. A espessura da cortical óssea do SSM nas regiões mais próximas dos ápices e área de furca foi similar apenas para os pré-molares.

Observation of 50 cases of effect of maxillary sinus floor augmentation with transalveolar technique and simultaneous implant / 中国基层医药

Objective To observe the effect of maxillary sinus floor augmentation with transalveolar tech-nique and simultaneous implant.Methods 50 cases of patients with missing tooth in maxillary posterior region with insufficient vertical bone treated by author were selected.Maxillary sinus floor augmentation with transalveolar tech-nique and simultaneous implantation were given after local anesthesia.X -ray was given on the right day,2 weeks, 3 months and 9 months after operation.And the situation of osseointegration was observed.Results There were 2 cases of injuries of maxillary sinus mucoperiosteum in the 50 cases (4%),and no obvious complication was found for timely treatment.There were 5 cases of gingiva with obviously swollen around implant and BOP(+),and the symptoms were obliterated one week after paradental basic therapy and oral health guidance were given.All the situations of the osseointegration of implants were good,and no loosening or dropping case was found in follow up.One year after operation,the mean obsorbation of bone around the neck of implant was (0.9 ±0.3)mm.There was no obvious absorption of bone around implant,and obvious continuous image of maxillary sinus floor could be observed by imaging examination.The satisfaction of chew,pronounce,aesthetics,maintenance and comfort was all 100%,and 49 cases were satisfied with operation tolerance,and satisfaction rate was 98%.Conclusion Ther effect is desired to apply maxillary sinus floor augmentation with transalveolar technique and simultaneous implant under strict indication.And the satisfaction degree is high.

Bone formation around rhBMP-2-coated implants in rabbit sinuses with or without absorbable collagen sponge grafting

PURPOSE: The purpose of this study was to evaluate bone formation around recombinant human bone morphogenetic protein (rhBMP-2)-coated implants placed with or without absorbable collagen sponge (ACS) in rabbit maxillary sinuses. METHODS: The Schneiderian membrane was elevated and an implant was placed in 24 sinuses in 12 rabbits. The space created beneath the elevated membrane was filled with either blood (n=6) or ACS (n=6). In the rabbits in which this space was filled with blood, rhBMP-2-coated and non-coated implants were alternately placed on different sides. The resulting groups were referred to as the BC and BN groups, respectively. The AC and AN groups were produced in ACS-grafted rabbits in the same manner. Radiographic and histomorphometric analyses were performed after eight weeks of healing. RESULTS: In micro-computed tomography analysis, the total augmented volume and new bone volume were significantly greater in the ACS-grafted sinuses than in the blood-filled sinuses (P<0.05). The histometric analysis showed that the areas of new bone and bone-to-implant contact were significantly larger in the AC group than in the AN group (P<0.05). In contrast, none of the parameters differed significantly between the BC and BN groups. CONCLUSIONS: The results of this pilot study indicate that the insertion of ACS after elevating the Schneiderian membrane, simultaneously with implant placement, can significantly increase the volume of the augmentation. However, in the present study, the rhBMP-2 coating exhibited limited effectiveness in enhancing the quantity and quality of regenerated bone.

Assessment of the autogenous bone graft for sinus elevation

OBJECTIVES: The posterior maxillary region often provides a limited bone volume for dental implants. Maxillary sinus elevation via inserting a bone graft through a window opened in the lateral sinus wall has become the most common surgical procedure for increasing the alveolar bone height in place of dental implants in the posterior maxillary region. The purpose of this article is to assess the change of bone volume and the clinical effects of dental implant placement in sites with maxillary sinus floor elevation and autogenous bone graft through the lateral window approach. MATERIALS AND METHODS: In this article, the analysis data were collected from 64 dental implants that were placed in 24 patients with 29 lacks of the bone volume posterior maxillary region from June 2004 to April 2011, at the Department of Oral and Maxillofacial Surgery, Inha University Hospital. Panoramic views were taken before the surgery, after the surgery, 6 months after the surgery, and at the time of the final follow-up. The influence of the factors on the grafted bone material resorption rate was evaluated according to the patient characteristics (age and gender), graft material, implant installation stage, implant size, implant placement region, local infection, surgical complication, and residual alveolar bone height. RESULTS: The bone graft resorption rate of male patients at the final follow-up was significantly higher than the rate of female patients. The single autogenous bone-grafted site was significantly more resorbed than the autogenous bone combined with the Bio-Oss grafted site. The implant installation stage and residual alveolar height showed a significant correlation with the resorption rate of maxillary sinus bone graft material. The success rate and survival rate of the implant were 92.2% and 100%, respectively. CONCLUSION: Maxillary sinus elevation procedure with autogenous bone graft or autogenous bone in combination with Bio-Oss is a predictable treatment method for implant rehabilitation.