Split crest con colocación simultánea de implantes en sector anterior: reporte de un caso / Split crest with simultaneous placement of implants in the anterior sector: a case report

La pérdida ósea en el sector anterior, ya sea por un defecto horizontal, vertical o combinado, actualmente es un desafío, no sólo por la integración del implante, sino por la estética involucrada. Entre las técnicas de regeneración ósea que permiten solucionar estos defectos, cabe destacar la técnica de expansión de crestas. Se presenta el caso de una paciente de 58 años con reborde atrófico, que se sometió a la expansión de crestas con colocación simultánea de implantes en sector anterior, con xenoinjerto previo a técnica de expansión de crestas con piezoeléctrico, colocación simultánea de implantes Narrow Connection SLActive Straumann. Se logró ganancia ósea y estabilidad primaria de los implantes, sin complicaciones. En escenarios seleccionados, la técnica de expansión de crestas de manera predecible permite ganancia de hueso horizontal adecuada, el éxito de los implantes con tasa de supervivencia y mínimas complicaciones intra y postoperatorias (AU)

Bone loss in the anterior sector, both a horizontal, vertical or combined defect is a challenge today; not only for the integration of the implant but also the aesthetic involved. There are techniques of bone regeneration that help us to solve this type of defects, among them we should highlight the crest expansion technique. We present the case of a 58-year-old patient with atrophic flange, who underwent the expansion of crests with simultaneous placement of implants in the anterior sector, with xenograft prior to the piezoelectric crest expansion technique, Simultaneous placement of Narrow Connection SLActive Straumann implants, bone gain and primary stability of the implants were obtained, without complications. In selected scenarios, the crest expansion technique could be considered a predictable approach that demonstrates a high implant survival rate, adequate horizontal bone gain, and minimal intra- and postoperative complications (AU)

Injerto en bloque en combinacióncon la técnica de split en dosfases para la rehabilitación deun caso de gran reabsorción óseadel maxilar en anchura / Block grafting in combination with the two-stage split technique for the rehabilitation of a case with severe bone resorption in width

El uso de diferentes técnicas quirúrgicas para lograr la resolución de los casos con atrofia más complejos es de vital importancia. Cada vez tenemos en la consulta casos con edentulismos de mayor duración que demandan tratamiento implantológico con prótesis fija, lo que supone un reto a la hora de planificar y llevar a cabo los tratamientos. Para ello, podemos utilizar diferentes técnicas que nos permitan ganar anchura y altura, así como implantes de distintas longitudes y diámetros que nos permitan adaptarnos a cada situación. En el presente caso clínico mostramos una rehabilitación que combina diferentes técnicas quirúrgicas para lograr el resultado buscado (AU)

The use of different surgical techniques to achieve the resolution of the most complex cases with atrophy is of vital importance. We have more and more cases with edentulism of longer duration that require implant treatment with fixed prosthesis, which is a challenge when it comes to planning and carrying out the treatments. For this, we can use different techniques that allow us to gain width and height as well as implants of different lengths and diameters that allow us to adapt to each situation. In this clinical case we show a rehabilitation that combines different surgical techniques to achieve the desired result (AU)

Modified Two-Stage Split Technique for Controlled Ridge Augmentation in Horizontally Atrophic Posterior Mandible: the First Stage of Research.

Various bone grafting methods are applied to eliminate horizontal atrophy of the jaws. However, problem complexity brings about ongoing research and development of new ways to achieve the predicted stable and long-term results of implantological treatment. The aim of the study was to evaluate the results of the developed method for bone grafting, a modified two-stage split technique for controlled ridge augmentation in horizontally atrophic posterior mandible, using radiological analysis data. MATERIALS AND METHODS: The study group included 18 patients with horizontally atrophic posterior mandible. According to cone beam computed tomography, 39 jaw segments were assessed before plastic surgery and after applying the two-stage split-crest technique for controlled ridge augmentation. The alveolar ridge width was estimated in the area of its top and at a distance of 1, 3, 5 mm from it using the vector of future implant position and taking into account the angle of inclination of the atrophic region of the mandible. RESULTS: When analyzing edentulous areas in the posterior mandible before treatment, there was rather a large angle of lingual inclination of the alveolar ridge. After 6 months, the average increase in bone tissue width in the region of the alveolar ridge top was 82%, it was 50.6% at a height of 1 mm from the top of the crest, 58.8% at 3 mm height, 46.7% at 5 mm (p≤0.05). Certain patterns of bone tissue growth were revealed depending on the structure of the reconstructed area. The most significant results were obtained in the molar segments of the mandible. CONCLUSION: The developed modified two-stage split technique for alveolar ridge augmentation allows achieving the required volume of bone tissue in the posterior mandible for successful implant treatment.

Bone remodeling around implants placed after socket preservation: a 10-year retrospective radiological study.

BACKGROUND: To evaluate and compare the long-term clinical and radiological outcomes of post-extraction sockets after ridge preservation either with porcine xenograft or collagen alone. Patients underwent single-tooth extraction in the posterior mandible. Fresh extraction sockets were filled with pre-hydrated cortico-cancellous porcine bone or collagen sponge. Two or 3 months later, a ridge expansion technique with immediate implant positioning placement was performed. Primary (alveolar width changes) and secondary outcomes (adverse events and long-term maintenance of buccal plate covering the implant) were evaluated. RESULTS: Thirty-four women and 20 men were selected: 30 implants (group A) placed into healed post-extraction sockets grafted with porcine bone and 24 (group B) into sockets filled with a collagen sponge. There was a significant loss in width in both groups from the first and second surgery (ranging between 2.7 mm and 4.5 mm). The ridge splitting with bone expansion resulted in significant long-term increases in width for both procedures and implant sites. Non-significant differences in alveolar width were registered between the groups at 10-year follow-up even if the analysis of the implant buccal bone coverage suggested that group A had significantly worst results. CONCLUSIONS: Porcine bone group had significantly better short-term outcomes with lower long-term maintenance of the buccal plate.

Split-crest technique with inlay bone block grafts for narrow posterior mandibles: a retrospective clinical study with a 3-year follow-up.

The use of the split-crest technique (SCT) and bone block grafts provides benefits to horizontal bone augmentation. However, no information is currently available to evaluate the clinical effects of SCT combined with inlay bone block grafts on soft and hard tissues of the narrow posterior mandibles. In this study, 56 healthy patients underwent SCT to augment the alveolar ridge width. Implant placement was performed 3 months after SCT, and the implants were restored 3 months after placement. A planned follow-up was performed to analyze various clinical features, including X-ray radiographs, alveolar ridge width, and keratinized mucosal width, after SCT to evaluate the success of the procedure. The incisions healed well in all patients. The average initial alveolar ridge width was 2.78 ± 0.56 mm, which increased to 6.67 ± 0.60 mm after SCT. Three months later, this width declined slightly to 6.19 ± 0.48 mm. The average initial keratinized mucosal width was 2.83 ± 0.66 mm, which increased to 6.00 ± 0.71 mm 3 months later. Both at 3 months and 1 year after the procedure, vertical bone loss at the buccal sites was 1.32 ± 0.56 mm and 1.94 ± 0.54 mm, respectively. Survival rates of the implants were 100% after 3 years. SCT with inlay bone block grafts was successfully applied to narrow posterior mandibles with efficient augmentation of soft and hard tissue widths. The findings of this study aim to identify future beneficial applications of SCT.

Minimal Invasive Flapless Piezotome Alveolar Crest Horizontal Split Technique: Preliminary Results.

INTRODUCTION: Alveolar split crest is an established surgical technique to enable implant insertion into narrow and atrophic alveolar crest. This surgical technique is adopted to position standard or large implants so that postextractive anatomy compromises with this attempt. The aim of this study was to evaluate the horizontal alveolar bone augmentation and its stability along time with a minimally invasive flapless technique. MATERIALS AND METHODS: Twenty-four implants were inserted in 10 patients during a 15-month period. Clinical parameters such as horizontal bone augmentation, intrasurgical complications, patient morbidity, implant loss, and vertical bone loss (VBL) were recorded in the first 3 years after surgery. Using cone-beam computed tomography (CBCT), alveolar bone width was measured for both implants position and bone reconstructions. 6 months later, at the time of implant integration, a new low-dose CBCT was performed. Implant survival (IS) and VBL were evaluated radiographically for 3 years. RESULTS: The initial bone thickness measured on the ridge is between 0.82 mm and 5.40 mm (average 2.43 mm), after the split crest the bone width is between 4.65 mm and 8.09 mm (average 6.39 mm). This leads to an increase in the alveolar bone width of between 0.80 mm and 6.01 mm (average 3.71 mm) on the ridge. No implant was lost at 3 years, and all implants are stable at the end of the study. Three years after the surgery, controls showed a VBL of between 0.0 mm and 1.2 mm (average 0.63 mm) around the inserted implants. These parameters suggest using a flapless technique to reduce bone resorption around the implant neck. CONCLUSION: A minimally invasive approach allows to reduce the surgical trauma and postsurgical discomfort. The complete vascular supply is maintained, the bone resorption is reduced, and the connective epithelium does not undergo postsurgical retraction, achieving the full maintenance of the residual keratinized gingiva. CLINICAL SIGNIFICANCE: A technique such as split crest can be a valid option to avoid autologous or heterologous bone grafts.

Comparison between immediate vs. delayed lateral expansion technique to augment narrow alveolar ridges for placement of implants - A pilot study.

OBJECTIVE: Narrow alveolar ridges pose a serious challenge for successful placement of endosseous implants and alveolar ridge widening procedure is indicated in cases of crest thickness of ≤4.0 mm. The study evaluated and compared, immediate and delayed techniques of implant placement using split crest technique to augment atrophic narrow alveolar ridges. METHODS: The study was carried out in 10 patients randomly divided into two groups of five each for immediate or delayed placement of implants. Implants were placed simultaneously after split crest procedure in immediate technique and after 3-4 weeks of healing in delayed technique. Data collected was statistically analyzed by SPSS version 22 using unpaired t-test, ANOVA and Pearson's correlation with p value = 0.05. RESULTS: Statistically significant (p = 0.000) difference was observed for implant stability at intra-op, 4 months and 6 months post-op between the two groups, however there was no statistically significant difference in amount of augmentation achieved between the two groups. CONCLUSION: We observed that both the techniques were comparable on the basis of augmentation achieved, implant success and survival rates, whereas implant stability was significantly higher in delayed technique group.

Application of the modified split crest technique of piezosurgery in mandible molar area / 实用医学杂志

Objective To evaluate the therapeutic outcome of horizontal bone augmentation by using the modified split crest technique of piezosurgery in mandible molar area. Methods The present study reviewed the record of 15 patients from 2016 January to 2017 March in the department of oral implantology center of Stomato-logical Hospital of Southern Medical University,who underwent the modified split crest technique of piezosurgery in mandible molar area. Preoperative CBCT was performed to determine the bone thickness of the toothless alveo-lar crest of the mandibular posterior region,and the bone thickness was less than 3 mm. The modified split crest technique of piezosurgery was performed for the horizontal bone augmentation at mandibular posterior region. Meanwhile,GBR and the postoperative CBCT were performed to determine the bone width increments,followed with 1-week anti-inflammatory therapy postoperation. Three months after the operations,the bone width incre-ment was examined by CBCT. SPSS13.0 software was used to analyze the collected data. Results The modified split crest technique of piezosurgery in mandible molar area was successfully established,resulting in the mini-mal operative wounds and the slight postoperative reaction,without obvious infection. The postoperative crest width increase achieved 6.05 ± 0.65 mm. At 3 months after operation,the crest width increase reduced to(5.81 ± 0.61)mm. There were significant differences of the alveolar ridge thickness between the preoperative and post-operative patients(P<0.05). There were significant differences between the preoperative crest width and the 3 months after treatment(P<0.05). Conclusion Horizontal bone augmentation of the modified split crest tech-nique of piezosurgery was efficient,which could be performed in very narrow alveolar ridge,and which was rela-tively safe and accurate,with less trauma. No damage was observed to the soft tissue,and the cutting direction can be well controlled.

Split crest: immediate expansion rim technique for rehabilitation of atrophic maxilla: a case report

While the deploy planning, we come across morphological changes in the intervention area and the bone volume, which is extremely important for the treatment outcome. The objective of this study is to describe the technique "Split-Crest" through a clinical case in which success was obtained. Demonstrate indications and advantages of the technique in order to gain a significant increase in bone density to achieve an excellent aesthetic and functional result. Female patient, leucoderma, 46 years old, attended the Dental Clinic of Specialization in Implantodontics of ESAMAZ, with report of early teeth loss and poorly adapted prosthesis in the upper anterior region of the pre jaw. During the clinical evaluation was observed Edentulism in the anterior arch of the jaw. Total tomographic filming was done on the jaws, the initial diagnosis was a severe resorption present in the premaxilla requiring regenerative process to achieve bone gain. During surgery the patient had immediate installation of previous implants in the region of the elements 12 and 22 through the technique of "Slplit-Crest", which consisted of two vertical cuts on the vestibular cortical portion and longitudinal osteotomy followed by the the shift vestibular cortical-spongy plate. Eight weeks later, the patient had clinically significant bone gain, proving the viability and success of the technique. A minimally invasive surgical procedure with well executed manipulation of tissue grafts and accelerates the clinical outcome, the working hours by the end of the treatment is smaller, has lower morbidity and lower operating costs.

Durante o planejamento do caso, foram encontradas alterações morfológicas na área de intervenção e do volume ósseo, que se torna extremamente importante para o resultado do tratamento. O objetivo deste estudo é descrever a técnica "Split-Crest" através de um caso clínico em que o sucesso foi alcançado. Assim, demonstrar indicações e vantagens da técnica, a fim de obter um aumento significativo na densidade óssea para obter um excelente resultado estético e funcional. Paciente do sexo feminino, leucoderma, 46 anos, procurou a Clínica de Especialização em Implantodontia da ESAMAZ, com relato de perda precoce de dentes e prótese mal adaptada na região anterior superior da pré-maxila. Durante a avaliação clínica foi observado o edentulismo no arco anterior da mandíbula. Solicitou-se uma Tomografia Computadorizada dos maxilares, e o diagnóstico inicial foi uma reabsorção grave presente na pré-maxila que requer processo regenerativo para obter ganhos ósseos. Durante a cirurgia, o paciente apresentou instalação imediata de implantes anteriores na região dos elementos 12 e 22 por meio da técnica de "Slplit-Crest", que consistiu em dois cortes verticais na porção cortical vestibular e osteotomia longitudinal seguido pela cortical vestibular - placa de repouso. Oito semanas depois, o paciente apresentou ganho ósseo clinicamente significativo, provando a viabilidade e o sucesso da técnica. Um procedimento cirúrgico minimamente invasivo com manipulação bem executada de enxertos de tecido e acelera o resultado clínico, tempo clínico menor, menor morbidade e menores custos operacionais.

Platelet-Rich Fibrin (PRF) in Implants Dentistry in Combination with New Bone Regenerative Flapless Technique: Evolution of the Technique and Final Results.

Most common techniques for alveolar bone augmentation are guided bone regeneration (GBR) and autologous bone grafting. GBR studies demonstrated long-term reabsorption using heterologous bone graft. A general consensus has been achieved in implant surgery for a minimal amount of 2 mm of healthy bone around the implant. A current height loss of about 3-4 mm will result in proper deeper implant insertion when alveolar bone expansion is not planned because of the dome shape of the alveolar crest. To manage this situation a split crest technique has been proposed for alveolar bone expansion and the implants' insertion in one stage surgery. Platelet-rich fibrin (PRF) is a healing biomaterial with a great potential for bone and soft tissue regeneration without inflammatory reactions, and may be used alone or in combination with bone grafts, promoting hemostasis, bone growth, and maturation. AIM: The aim of this study was to demonstrate the clinical effectiveness of PRF combined with a new split crest flapless modified technique in 5 patients vs. 5 control patients. MATERIALS AND METHODS: Ten patients with horizontal alveolar crests deficiency were treated in this study, divided into 2 groups: Group 1 (test) of 5 patients treated by the flapless split crest new procedure; Group 2 (control) of 5 patients treated by traditional technique with deeper insertion of smaller implants without split crest. The follow-up was performed with x-ray orthopantomography and intraoral radiographs at T0 (before surgery), T1 (operation time), T2 (3 months) and T3 (6 months) post-operation. RESULTS: All cases were successful; there were no problems at surgery and post-operative times. All implants succeeded osteointegration and all patients underwent uneventful prosthetic rehabilitation. Mean height bone loss was 1 mm, measured as bone-implant most coronal contact (Δ-BIC), and occurred at immediate T2 post-operative time (3 months). No alveolar bone height loss was detected at implant insertion time, which was instead identified in the control group because of deeper implant insertion. CONCLUSION: This modified split crest technique combined with PRF appears to be reliable, safe, and to improve the clinical outcome of patients with horizontal alveolar crests deficiency compared to traditional implanting techniques by avoiding alveolar height-loss related to deeper insertion of smaller implants.

The split crest technique and dental implants: a systematic review and meta-analysis.

This systematic review aimed to determine: (1) the expected bone volume gain with the split crest technique, and (2) how the use of surgical instruments affects the performance of this technique. An electronic search was performed in the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Embase, PubMed/MEDLINE, Scopus, and Web of Science databases. Twenty-seven articles met the selection criteria and were subjected to meta-analysis of bone gain and survival rate; 17 reported the use of conventional surgical instruments and nine the use of surgical ultrasound. A total of 4115 implants were installed in 1732 patients (average patient age 52 years). The overall implant survival rate was 97%. The average bone gain in studies that used conventional surgical instruments was 3.61mm, while this was 3.69mm in those that used ultrasound. Only two studies presented a low risk of bias. The greatest problems identified during the qualitative analysis were related to random selection of the population and the absence of statistical analysis. The split crest technique appears to be a promising and effective technique to gain bone width, regardless of the surgical instruments used. Considering the diversity of the studies and implant types, no definitive recommendations can be made, especially with regard to the best instruments and implant design to be used.

Platelet-rich fibrin (PRF) in implant dentistry in combination with new bone regenerative technique in elderly patients.

INTRODUCTION: Some studies have demonstrated that platelet rich fibrin (PRF) is a healing biomaterial with a great potential for bone and soft tissue regeneration, without any inflammatory reactions and may be used alone or in combination with bone grafts, promoting hemostasis, bone growth, and maturation. PRF appears as a natural and satisfactory aid in bone regenerative surgery in elderly patients with favorable results and low risks. AIM: This study wants to demonstrate how PRF in association with a new split crest augmentation technique can be a great aid in implant rehabilitation, especially in the elderly patients, when bone regeneration is required. MATERIALS AND METHODS: Ten patients were treated in this study, five following the flapless split crest new procedure and other five patients following traditional procedure without split crest as control. Five patients with an average age between 50 and 60 years were selected to be operated with a split crest flapless modified technique in order to optimize the regenerative conditions with a bone augmentation and implant insertion in one single stage procedure. For all the patients autologous PRF has been used to fill the split crest gap or simply as regenerative material. Orthopantomography, intraoral radiography and CT DentaScan/CT Cone beam were performed for every patient before the treatment and at follow-up time exeption made for CT. RESULTS: All cases were successful, there were no problems at surgery time, at post-operative and at osteointegration periods. All implants achieved osteointegration. These results were obtained by accurately managing immediate and late post operative period in all of the operated cases. Mean difference for height bone loss between the two groups of patients was 2.4mm at T1 and 2.2mm at T3. DISCUSSION: The rationale of this split crest flapless modified technique is to obtain a proper buccal cortex expansion preserving its vascular supply avoiding periosteal elevation for better cortical bone nourishing. Moreover, advantages are reported related to the use of PRF. The effectiveness of PRF is shown in promoting the healing of surgical wounds, it has, in fact, platelet growth factors that can improve the vascularisation of the surgical site, promoting neoangiogenesis. Furthermore, by simply changing the settings of the centrifuge, it is possible to obtain a normal gelling if it has to be used as regenerative and stimulating material, or more consistent substance to be used as a filler in the split crest gap. CONCLUSIONS: The main advantages in using the platelet-rich fibrin are healing and bone regenerative properties in combination with its complete resorption after surgery, thus avoiding a second surgery time, important factor in the elderly patients. Currently, it is a minimally invasive technique with low risks and satisfactory clinical results such preventing complications or implant failure particularly in elderly patients for age related conditions.

The alveolar ridge splitting/expansion technique: a systematic review.

PURPOSE: The aim of this systematic review was to evaluate clinical, radiological and histological outcomes of the alveolar ridge splitting/expansion technique (ARST) with or without GBR. MATERIALS AND METHODS: A screening of two databases MEDLINE (PubMed) and EMBASE (OVID) and hand search of articles were performed. Human and animal studies reporting on dental implants placed with simultaneous ARST up to May 31st 2014 were considered. Quality assessment of selected full-text articles was performed according to the ARRIVE guidelines and the Cochrane collaboration's tool to assess risk of bias. RESULTS: Overall, 18 human and six animal studies (risk of bias: high/unclear) were included in this review. No randomized controlled trials were found. Due to the heterogeneity of study designs, definitions of success criteria, outcome variables, observation times and surgical procedures, no meta-analysis was performed. Reported survival (18 studies) and success (nine studies) rates ranged from 91.7 to 100% and 88.2 to 100%, respectively, with a mean follow-up of 1-10 years. Crestal bone level changes (∆CBL) in some studies indicate slightly higher bone loss before and after loading. Histologic and histomorphometric data from six animal studies confirm the crestal bone loss, particularly at buccal sites. CONCLUSIONS: Within the limitations of this review, ARST seems to be a well-functioning one-stage alternative to extended two-stage horizontal grafting procedures. Data indicate that during healing and first year of loading, increased ∆CBL particularly at buccal sites must be anticipated. Additional horizontal GBR can help to preserve buccal bone height and width.

Bone healing at implants with different surface configurations: an experimental study in dogs.

OBJECTIVE: To study osseointegration of implants with surface modifications by the use of fluoroboric acid and/or H2 O2 installed in conventional sites or sites with circumferential marginal defects. MATERIAL AND METHODS: Four implants with different surfaces were used. One basic surface (ZirTi(®)) was sandblasted with zirconium microspheres and acid etched additionally with hydrofluoric acid. A second surface was treated with fluoroboric acid instead of hydrofluoric acid. The remainder of the other two surfaces was additionally treated with H2O2. The edentulous mandibles of 6 foxhound dogs were used to randomly install 8.5-mm-long implants with the different surfaces and to study the histological healing after 1 and 3 months. To study osteoconductivity, additional four recipient sites were prepared with the coronal region being widened so that a 4 mm deep and 0.85 mm wide marginal defect resulted after the placement of the four implants with different surfaces. No filler material or membranes were used, and a fully submerged healing was allowed for 3 months. RESULTS: At the conventional sites, new bone formation ranged between 68.5% and 74.9% after 1 month. After 3 months, bone-to-implant contact ranged from 72.6% at the ZirTi(®) surface to 84.1% at the fluoroboric acid-treated implants, the difference being statistically significant. At the sites with marginal defects, bone formation ranged from 0.77 mm at the surface treated with fluoroboric acid and H2O2 , to 1.93 mm at the surface treated with fluoroboric acid alone. CONCLUSIONS: Fluoroboric acid treatment alone of titanium implant surfaces resulted in improved osseointegration and osteoconductivity after 3 months.

Immediate Loaded Implants in Split-Crest Procedure.

BACKGROUND: The aim of this study was to assess survival rate of immediate loading implants placed after split-crest technique. METHODS: Thirty-six patients were enrolled in the study. They underwent placement of 93 dental implants in edentulous region after split-crest ridge expansion procedure. Implants followed an immediate loading procedure. Crestal bone levels were measured at baseline, at temporary prosthesis placement, at 1 year, and at 2 years from implant placement. RESULTS: For dental implants, a survival rate of 98.92% was reported at 2-year follow-up, with a mean value bone loss of -1.02 ± 0.48. CONCLUSION: This study assessed immediate loading implant placement after split-crest procedure at 2-year follow-up.

Long-term outcomes from implants installed by using split-crest technique in posterior maxillae: 10 years of follow-up.

OBJECTIVE: The aim of the present 10-year retrospective study was to evaluate the success and survival rates of narrow diameter implants (NDIs) placed in combination with a split-crest technique. MATERIALS AND METHODS: Twenty-one healthy individuals who received prosthetic rehabilitation supported by narrow diameter implants (NDIs) installed in atrophic maxillary posterior areas immediately after split-crest procedure were included in the study. Six to eight weeks after implant placement, the prosthetic rehabilitations were delivered. Periapical radiographs were taken at the 6-month and 10-year time interval after implant loading to assess bone marginal level around the implants. In addition, survival and success indexes were also obtained at these time intervals. RESULTS: Forty NDIs were placed in 21 patients. At the end of the 10-year follow-up period, seven patients had dropped out, two implants were lost, and nine prostheses presented some type of deficiency (ceramic fracture or retaining screw fracture). At the 10-year time interval, the implant survival rate was 97% and the success rate was 95%. The marginal bone loss at the 6-month and 10-year time intervals was, respectively, 0.47 (SD 0.91) mm and 1.93 (SD 0.93) mm. CONCLUSION: Narrow diameter implants installed immediately after split-crest procedure may successfully support prosthetic rehabilitations after long-time intervals.

Influence on alveolar resorption of the buccal bony plate width in the edentulous ridge expansion (E.R.E.)--an experimental study in the dog.

OBJECTIVE: To compare the hard tissue changes at implants installed applying edentulous ridge expansion (E.R.E.) at sites with a buccal bony wall thickness of 1 or 2 mm. MATERIAL AND METHODS: In six Labrador dogs, the first and second maxillary incisors were extracted, and the buccal alveolar bony plates and septa were removed. After 3 months of healing, partial-thickness flaps were dissected, and the E.R.E. was applied bilaterally. Hence, an expansion of the buccal bony crest was obtained in both sides of the maxilla with a displacement of either a 1- or a 2-mm-wide buccal bony plate at the test and control sites, respectively. After 3 months of healing, biopsies were obtained for histological analyses. RESULTS: A buccal vertical resorption of the alveolar crest of 2.3 ± 0.8 and 2.1 ± 1.1 mm, and a coronal level of osseointegration at the buccal aspect of 2.7 ± 0.5 and 2.9 ± 0.9 mm were found at the test (1 mm) and control (2 mm) sites, respectively. The differences did not reach statistical significance. The mean values of the mineralized bone-to-implant contact (MBIC%) ranged from 62% to 73% at the buccal and lingual sites. No statistically significant differences were found. Horizontal volume gains of 1.8 and 1.1 mm were observed at the test and control sites, respectively, and the difference being statistically significant. CONCLUSIONS: Implants installed using the E.R.E. technique yielded a high degree of osseointegration. It is suggested that the displacement of buccal bony plates of 1 mm thickness is preferable compared with that of wider dimensions.

Modified edentulous ridge expansion technique and immediate implant placement: a 3-year follow-up.

Restoration of the edentulous alveolar ridge with implants often requires the ridge width to be augmented to allow its placement. The aim of this study was to evaluate the split-crest technique, with subepithelial connective tissue graft used as biological barrier, in patients with narrow ridges, focusing on the status of soft and hard tissues and on implant success rate, at 36 months after implant loading. Thirteen patients (6 males and 7 females), ages 32-68 years (mean 49.4 years) with an atrophic maxillary jaw underwent modified edentulous ridge expansion technique for implant placement. A total of 33 Laser-Lok tapered internal implant, were placed in the maxilla. The following parameters were evaluated: (1) initial ridge width (time t0); (2) ridge width at the time of abutment connection (time t1); four months after implants placement, healing abutments were connected and the prosthetic rehabilitation was initiated, and all patients were evaluated clinically and radiographically with periapical radiograph at intervals of 3-6 months for the first year and annually thereafter for 3 years. The ridge width was measured with a cone beam computed tomography. The initial ridge width ranged from 3.5 mm to 7 mm (mean: 4.67 mm), while at the end of the expansion procedure the width ranged from 6.3 mm to 11.0 mm (mean: 8.2 mm). The width gain of the edentulous ridge ranged from 1.45-4.9 mm (mean: 3.5 mm). Two implants became exposed 1 month after surgery. One implant was lost before loading (3%). The diameter of failed implant was 5.8 mm and length was 10.5 mm. The remaining 32 implants were stable and free of complications at the end of the study. Thus, the implant survival rate was 97%. Because no implant failed after loading, the cumulative survival rate of loaded implants was 100%. The minimally invasive regenerative technique presented here avoids the use of bone graft, secondary surgery for soft tissue augmentation, and mechanical expansion devices. However, the follow-up period for outcome evaluation and exiguous patient's number in this series was limited.

Outcomes and treatments of mal fractures caused by the split-crest technique in the mandible.

In this study, we investigated cases of mal fracture occurring during the split-crest procedure. In all subjects (six patients), the free cortical bone segment caused by the mal fracture was carefully maintained in the lateral position without fixation using a titanium plate or screw. On pre- and postoperative multiplanar reconstruction CT, the average total alveolar increase was 5.0 mm in the lower portion 1 mm from the top of the alveolar ridge, and the average total alveolar increase in the lower portion 11 mm from the top of the alveolar ridge was 2.2 mm. A total of 11 dental implants were placed immediately at the same time as the split-crest procedure, while three dental implants were placed after a waiting period of 4-11 months from bone augmentation. During an average follow-up of 27.8 months, there were no complications or cases of failed implants. Consequently, among the patients who experienced mal fracture during the split-crest technique, a sufficient volume of alveolar bone was obtained without the need for rigid fixation of the free bone segment, and the dental implants placed within the area of the mal fracture showed a good prognosis.

The edentulous ridge expansion (ERE) technique an experimental study in the dog.

OBJECTIVE: To compare the healing and bony crest resorption at implants installed conventionally or applying an edentulous ridge expansion (ERE) technique in the maxilla. MATERIAL AND METHODS: In six Labrador dogs, the first and second maxillary incisors were extracted bilaterally. In the left side of the maxilla (Test), the flaps were elevated and the buccal plate of the alveoli and septa was removed. After 3 months of healing, partial-thickness (split) flaps were dissected and the residual alveolar bone was exposed. In the right side of the maxilla, an implant was installed conventionally (Type IV; Control) while, in the left side, the ERE technique was adopted. Hence, an expansion of the buccal bony crest was obtained, and the implant was subsequently installed (Test). After 3 months of healing, biopsies were obtained and ground sections were prepared for histological analyses. RESULTS: A buccal vertical resorption of the bony crest of 2.2 ± 1.2 mm and 1.6 ± 0.7 mm was found at the test and control sites, respectively. The difference, however, did not reach statistical significance. The coronal level of osseointegration at the buccal aspect was located at 3.1 ± 1.0 mm and 2.2 ± 0.7 mm from the implant shoulder at the test and control sites, respectively, the difference being statistically significant. The mean values of the mineralized bone-to-implant contact (MBIC%) ranged from 43% to 48% at the buccal and lingual sites. No differences reached statistical significance. CONCLUSIONS: Implants installed by applying an ERE technique may osseointegrate similarly to conventional implant installation. However, vertical and horizontal resorption of the displaced buccal bony wall occurred as well.