International Journal of Periodontics & Restorative Dentistry最新文献

The aim of this morphometric study was to precisely determine the 3D characteristics of the root complex of the posterior dentition. Extracted and well-preserved permanent posterior teeth were included in this analysis and grouped based on tooth type and arch location. All teeth were digitally scanned. Morphologic and dimensional features of the root complex were assessed, including length and surface area of the root trunk and individual roots, width of root concavities (RC), and furcation entrance, when present. A total of 240 posterior teeth comprised the study sample. The root complex of multirooted maxillary first premolars presented with a long root trunk (10.49 mm), representing 65.52% of the surface area, and two short roots comprising the remaining 34.8% of the surface area. Root trunks of mandibular molars were an average of 0.8 mm shorter than their maxillary counterparts. Class III furcation involvement is expected in all maxillary and mandibular molars, as well as multirooted maxillary first premolars, after 4.80 mm and 10.49 mm of clinical attachment loss, respectively. RCs were a common finding among the evaluated dentitions. The root complex morphology varies among the maxillary and mandibular posterior dentition. RCs are highly prevalent in both maxillary and mandibular dentition. The findings derived from this study can be utilized in daily clinical practice for the adequate management of posterior dentition and serve as a reference for future investigations in dental anatomy and digital technology. Also, these findings can guide the industry into creating and redefining tools that adequately adapt to the anatomical characteristics and variations of the specific tooth type.

Tooth autotransplantation is an effective treatment to replace missing teeth. Digital planning can facilitate successful autotransplantation. Guiding templates are highly recommended when performing cases in healed ridges in the posterior area to reduce excessive bone loss and increase the chances of fitting the donor tooth in the new socket. This case report highlights the use of 3D planning tools and fully guided drilling templates for successful tooth autotransplantation in the posterior area. Two tooth autotransplantations were performed in a 51-year-old patient using mandibular third molars to replace hopeless mandibular first and second molars. Root canal treatments were carried out before the surgeries, and different alveoloplasty techniques were used in each recipient area. The prosthetic phase was carried out after 9 months. Both teeth were asymptomatic, functional, and exhibited no signs of resorption or apical radiolucency and showed complete regeneration of the periodontal apparatus at the 2-year follow-up.

The introduction of a new collagen substitute, which will potentially reduce the invasiveness of techniques by avoiding the need for a second surgical site (ie, the donor site), needs to be evaluated in relation to the surgical procedure that could benefit the most by utilizing such a matrix. This study compared the clinical outcomes following treatment of RT1 multiple adjacent gingival recessions (MAGRs) using the modified coronally advanced tunnel (MCAT) technique or the multiple coro- nally advanced flap (MCAF) in conjunction with a new volume-stable xenogeneic collagen matrix (VXCM). Secondarily, the study evaluated whether patients report a preference between the two surgical techniques in terms of discomfort. A total of 20 patients requiring treatment of MAGRs were randomly assigned to one of the two treatment groups: MCAF+VCMX (Group A) or MCAT+VCMX (Group B). The following measurements were recorded at baseline (before surgery) and at 6 and 12 months: gingival recession depth (REC), probing pocket depth (PD), keratinized tissue width (KTW), and gingival thickness (GT). Postoperative pain and discomfort were recorded using a visual analog scale (VAS) at 1 week. The primary outcome variable was mean root coverage (mRC), and second- ary outcomes were complete root coverage (CRC), changes in KTW and GT, patient discomfort and satisfaction, and duration of surgery. Healing was uneventful in both groups. At 12 months, both treatments resulted in statistically significant improvements in REC and GT compared to baseline (P < .05). The mRC was 79.95% ± 29.92% in the MCAF group and 64.74% ± 40.5% in the MCAT group (P = .124). CRC was seen in 65.6% of MCAF-treated sites and 52% of MCAT-treated sites (P = .181). Similar clinical results should be expected when MAGRs are treated with MCAF or MCAT, with the adjunct of VCMX.

Implants with deficient papillae and black triangles are common findings. The treatment of these esthetic complications is considered to be challenging with limited predictability. Therefore, the present report aims to describe a novel technique for papilla augmentation: the 'iceberg' connective tissue graft (iCTG) after extraction and interproximal bone reconstruction in the anterior region. A 35-year-old patient presented with a hopeless tooth with interproximal clinical attachment loss extending to the apical third of the adjacent tooth. Interproximal bone reconstruction was performed through alveolar ridge preservation by directly applying recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to the exposed root surface of the adjacent tooth. A mixture of autogenous bone chips (obtained from the ramus) and bovine bone xenograft particles (previously mixed with the growth factor) was also used. The patient was able to return for implant therapy only 2 years later, at which time an incomplete regeneration of the interproximal bone was observed. Therefore, to compensate the interproximal deficiency, the iCTG approach was utilized, involving a double layer of CTG with different origins. Two small grafts from the tuberosity were sutured to the mesial and distal ends of a wider CTG harvested from the palate, aiming to gain additional volume at the interproximal sites. The composite graft was then sutured on top of the implant platform, and the flap was then released and closed by primary intention. After conditioning the peri-implant tissues, the case was finalized with a satisfactory outcome. The described iCTG could be an effective approach for reconstructing peri-implant papillae following interproximal bone reconstruction.

This technical report describes the simplified subperiosteal sling (SPS) suture for connective tissue graft (CTG) stabilization in root coverage and phenotype modification of single and multiple reces- sion defects via the vestibular incisional subperiosteal tunnel access (VISTA). The simplified SPS suture engages only the CTG and stabilizes it to the tooth in the coronal-most position, inside the subperiosteal tunnel, independent of the overlying gingival tissue. The simplified SPS suture differs from the original SPS suture in that it engages the CTG first, and the needle and tail of the suture are knotted before the suture is introduced into the subperiosteal tunnel. This allows the needle to pass through the subperiosteal tunnel only once from the vestibular access to the intended gingi- val sulcus. When multiple teeth are treated, only one simplified SPS suture traverses the vestibular access at a time, as the CTG is incrementally advanced into the tunnel. This prevents suture entan- glement and improves the practical application of the technique.

This retrospective study evaluated the survival rate and the clinical outcome of an endosseous implant system, as well as the marginal bone level (MBL) and the impact of the machined collar neck position on crestal bone level changes up to 2 years later. A total of 96 implants were placed in 57 patients and loaded with a final restoration after at least 3 months of healing: 15 implants were immediately placed into fresh extraction sockets, and 81 were placed in healed ridges. Marginal bone loss around implants was determined radiographically at 12 to 24 months postloading. The effects on marginal bone loss of the site (mandible vs maxilla), location (anterior vs posterior), immediate vs delayed implant, smoking habit, sex, implant length and diameter, prosthesis type (screw-retained/cemented), and the machined collar position were evaluated. The implant survival rate was 98.96% at 1 year. The mean MBL decreased significantly (0.238 mm) between baseline and loading (P < .001; post hoc test) and decreased by 0.154 mm between loading and 1 year, but this was not significant (P = .085; post hoc tests). After 2 years, the mean MBL decreased significantly (0.263 mm) between baseline and loading (P < .001) and decreased by 0.111 mm between loading and 1 year and by 0.199 mm between loading and 2 years, but these were not significant (P > .05; post hoc tests). The mean bone loss after 1 and 2 years was not significantly associated with implant type or site, smoking habit, or type of implant surgery (P = .792). However, the mean bone loss was significantly associated with the type of prosthesis and was significantly greater for cemented prostheses compared to screw-retained prostheses. A supracrestal position of the machined collar (tissue level) was associated with no bone loss, while placing the collar below the alveolar crest led to bone loss over 2 years. Of the factors evaluated, marginal bone loss after 1 and 2 years was significantly associated with prosthesis type and the machined collar position.

The biggest challenge during periodontal regeneration in the anterior region is the prevention of soft tissue recession. Minimally invasive surgeries, particularly papilla preservation techniques and soft tissue augmentation, may significantly reduce such postoperative soft tissue recession. This article presents the vestibular incision subperiosteal tunnel access (VISTA) approach for periodontal regeneration in the anterior region. A subperiosteal tunnel prepared from a single vertical vestibular incision adjacent to the defect is used for debridement, application of enamel matrix derivative, defect grafting with corticocancellous tuberosity bone, and insertion of the connective tissue graft. Evaluation of six cases with up to 6 years of follow-up showed improvements in all clinical parameters. The probing pocket depth improved from 8.2 ± 0.75 mm initially to 2.7 ± 0.52 mm at follow-up, clinical attachment level improved from 8.5 ± 0.83 mm initially to 2.7 ± 0.52 mm at follow-up, and midfacial gingival recession of 1 mm at two sites was corrected. The papillae were stable at all sites, with an average distance of 4.8 mm from the incisal edge to the papilla tip. This technique seems to be a promising approach for achieving both esthetic and functional goals of periodontal regenerative surgery. However, experience in performing microsurgeries and harvesting tuberosity tissues may be a limitation.

Two fractured maxillary central incisors were restored via the crown fragment reattachment technique with adhesive systems and composite resin material. A long-term successful outcome was achieved after 4 years of follow-up. The patient presented with fractured maxillary central incisors, and a comprehensive intraoral and radiographic examination revealed that both teeth had extended crown fractures with no pulpal exposure (Class II, Ellis and Davey). The tooth fragments were thoroughly cleaned and inspected before being repositioned. Both fragments were in excellent condition with almost no pieces missing. Therefore, the proposed treatment was fragment reattachment. After verifying the repositioning and adaptation of the fractured fragments, a flowable composite was used to perform the reattachment procedure under rubber dam isolation. With modern dental adhesives, the reattachment of tooth fragments in good condition is considered a more conservative option for restoring tooth morphology, esthetics, and function. Although one tooth showed signs of irreversible pulpitis and required root canal treatment 2 weeks after the restoration, the clinical and radiographic evaluations at the 4-year follow-up visits confirmed the success of the restorative treatment. The restorations showed good functional and esthetic outcomes after 4 years of follow-up.

The primary aim of this study was to assess the histomorphometric outcomes of extraction sockets grafted with freeze-dried bone allograft (FDBA) and sealed with a collagen membrane after 3 months of healing in specific region of interest (ROI) areas. The secondary aims were to analyze the biomaterial resorption rate, the bone-to-biomaterial contact (BBC), and the area and perimeter of grafted particles compared with commercially available FDBA particles. Fifteen patients underwent tooth extractions and ridge preservation procedures performed with FDBA and a collagen membrane. Bone biopsy samples were harvested after 3 months at the time of implant placement for histologic and histomorphometric analysis. Two areas of concern (ROI1 and ROI2) with different histologic features were identified within the biopsy samples; ROI1, ROI2, and commercially available particles were analyzed and compared. The following parameters were analyzed: newly formed bone, marrow space, residual graft particles, perimeter and area of FDBA particles, and BBC. The histomorphometric analysis showed 35.22% ± 10.79% newly formed bone, 52.55% ± 16.06% marrow spaces, and 12.41% ± 7.87% residual graft particles. Moreover, the histologic data from ROI1 and ROI2 showed that (1) the mean percentage of BBC was 64.61% ± 27.14%; (2) the newly formed bone was significantly higher in ROI1 than in ROI2; (3) the marrow space was significantly lower in ROI1 than in ROI2; and (4) the FDBA particles in ROI1 sites showed significantly lower area and perimeter when compared to commercially available FDBA particles. This latter data led to the hypothesis that FDBA particles embedded in newly formed bone undergo a resorption/remodeling process.

Subperiosteal implants were first introduced in the early 1940s for the treatment of edentulous maxillary and mandibular arches with severe bone atrophy. After achieving widespread popularity in the 80s and 90s, this denture therapy was progressively abandoned due to significant technique limitations, including high rates of infection and the complications and difficulties with positioning implants and obtaining sufficiently extensive bone impressions. In the last two decades, digital technology has dramatically changed the world of implant dentistry. In particular, modern diagnostic imaging, digital technology, and direct metal laser sintering now allow for the projection of implants with the proper extension, leading to the fabrication of custom-made titanium meshes that perfectly fit the specific anatomical requirements of patients. With modern production methods, subperiosteal implants have been digitally reinterpreted, and interest in them is being renewed for the treatment of edentulous patients with atrophic arches. This article describes the evolution of subperiosteal implants in recent years and presents two clinical cases involving the placement of new generation (NG) subperiosteal implants with the clinical and radiographic findings at the 1-year follow-up.