Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 60
Filter
1.
BMC Oral Health ; 24(1): 531, 2024 May 04.
Article in English | MEDLINE | ID: mdl-38704566

ABSTRACT

BACKGROUND: Oral Health-Related Quality of Life (OHRQoL) is a comprehensive concept covering daily comfort, self-esteem, and satisfaction with oral health, including functional, psychological, and social aspects, as well as pain experiences. Despite abundant research on OHRQoL related to oral diseases and hygiene, there is limited data on how patients perceive changes after implant-prosthetic rehabilitation. This study aimed to evaluate OHRQoL and aesthetic perception using OHIP-14 and VAS scales respectively, before (baseline-TB), during (provisional prostheses-TP), and after (definitive prostheses-TD) implant-prosthetic rehabilitation. It also explored the impact of biological sex, substitution numbers, and aesthetic interventions on OHRQoL and VAS scores, along with changes in OHIP-14 domains. METHODS: A longitudinal prospective single-center observational cohort study was conducted with patients requiring implant-prosthetic rehabilitation. Quality of life relating to dental implants was assessed through the Italian version of Oral Health Impact Profile-14 (IOHIP-14), which has a summary score from 14 to 70. Patients' perceived aesthetic was analyzed through a VAS scale from 0 to 100. Generalized Linear Mixed Effect Models, Linear Mixed Effect Models, and Friedman test analyzed patient responses. RESULTS: 99 patients (35 males, 64 females) aged 61-74, receiving various prosthetic interventions, were enrolled. Both provisional and definitive prosthetic interventions significantly decreased the odds of a worse quality of life compared to baseline, with odds ratios of 0.04 and 0.01 respectively. VAS scores increased significantly after both interventions, with estimated increases of 30.44 and 51.97 points respectively. Patient-level variability was notable, with an Intraclass Correlation Coefficient (ICC) of 0.43. While biological sex, substitution numbers, and aesthetic interventions didn't significantly affect VAS scores, OHRQoL domains showed significant changes post-intervention. CONCLUSIONS: These findings support the effectiveness of implant-prosthetic interventions in improving the quality of life and perceived aesthetics of patients undergoing oral rehabilitation. They have important implications for clinical practice, highlighting the importance of individualized treatment approaches to optimize patient outcomes and satisfaction in oral health care.


Subject(s)
Dental Prosthesis, Implant-Supported , Esthetics, Dental , Oral Health , Quality of Life , Humans , Male , Female , Prospective Studies , Dental Prosthesis, Implant-Supported/psychology , Middle Aged , Aged , Longitudinal Studies
2.
Clin Oral Implants Res ; 35(5): 547-559, 2024 May.
Article in English | MEDLINE | ID: mdl-38372478

ABSTRACT

OBJECTIVES: The effect of the implant position within the prosthesis on bone remodeling is scarcely documented so far. Thus, the aim of the present study was to investigate whether central implants may suffer higher peri-implant marginal bone levels (MBL) compared to laterals in case of fixed splinted bridges supported by ≥ three implants. MATERIALS AND METHODS: Partially edentulous subjects rehabilitated with at least one fixed bridge supported by ≥ three dental implants were enrolled. MBL was assessed radiographically by means of intraoral radiographs acquired with phosphor plates and imported in a dedicated software. MBL was calculated as the distance between the implant platform level and the most coronal visible bone-to-implant contact. A three-level linear mixed effects model was used for investigating the fixed effect of patient-, prosthesis-, and implant-level variables on the MBL. RESULTS: Overall, 90 patients rehabilitated with 130 splinted fixed bridges supported by 412 implants were included. The median follow-up was 136 months. The mean peri-implant MBL resulted statistically significantly higher at central implants if compared to lateral implants (p < .01). The estimated MBL averages for central and external implants were 1.68 and 1.18 mm, respectively. The prosthesis-level variables suggested that a cement-retained bridge was prone to a significant 0.82 mm higher MBL than a screw-retained one. Implant surface showed an association with MBL changes, although less pronounced than implant retention. CONCLUSIONS: In case of ≥3 adjacent implants supporting splinted bridges, central implants were more predisposed to MBL compared to laterals. At the prosthesis level, implants supporting cement-retained bridges were statistically more susceptible to MBL compared to screw-retained ones. Surface characteristics can also influence MBL stability at the implant level.


Subject(s)
Dental Implants , Dental Prosthesis, Implant-Supported , Denture, Partial, Fixed , Humans , Retrospective Studies , Female , Male , Middle Aged , Aged , Alveolar Bone Loss/diagnostic imaging , Alveolar Bone Loss/etiology , Jaw, Edentulous, Partially/surgery , Jaw, Edentulous, Partially/rehabilitation , Adult
3.
Int J Periodontics Restorative Dent ; 0(0): 1-23, 2024 02 16.
Article in English | MEDLINE | ID: mdl-38363182

ABSTRACT

The present case series aims to investigate the use of polynucleotides mixed with hyaluronic acid (PNs-HA) in the form of gel to promote bone regeneration in horizontal alveolar defects. Overall, 6 adult patients underwent localized horizontal guided bone regeneration by means of xenogeneic bone substitute and a resorbable barrier with a staged approach. The graft consisted in a mixture of deproteinized bovine bone mineral (DBBM) particles and PNs-HA gel in a 3:1 ratio, respectively. The material was covered by a resorbable collagen membrane fixed with pins to the underlying bone. Implant placement was performed after 5 months. Healing proceeded uneventfully, and, upon re-entry, the graft appeared well vascularized and firmly attached to the recipient bone. Histologically, the regenerated bone appeared highly mineralized, well-organized in lamellae and totally embedding the residual granules of the biomaterial. Histomorphometric evaluations revealed that newly formed bone occupied on average 41.2% ± 12.4% of the analysed samples. Linear measurements performed on CBCT scans yielded an overall linear horizontal bone gain of 4.91 ± 0.88 mm. These data suggest that a mixture of DBBM and PNs-HA can be safely used to promote bone regeneration in case of horizontal alveolar defects.

4.
J Clin Med ; 12(24)2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38137716

ABSTRACT

BACKGROUND: Traditional screw or cemented connections in dental implants present limitations, prompting the exploration of alternative methods. This study assesses the clinical outcomes of single crowns and fixed partial prostheses supported by conometric connections after one year of follow-up. METHODS: Twenty-two patients received 70 implants, supporting 33 rehabilitations. Biological responses and prosthodontic complications were evaluated at baseline, 6 months, and 12 months. RESULTS: All implants exhibited successful osseointegration, with no losses or peri-implant inflammation. Marginal bone levels showed minimal changes, well below pathological thresholds. The difference in marginal bone loss (MBL) was -0.27 ± 0.79 mm between T0 and T1, and -0.51 ± 0.93 mm between T0 and T2. No abutment screw loosening or crown chipping occurred. However, coupling stability loss was observed in nine cases. CONCLUSIONS: The conometric connection demonstrated successful integration and minimal complications after one year. This alternative shows promise, particularly in simplifying handling and improving marginal adaptation. Further research with larger sample sizes and longer follow-up is warranted for comprehensive validation.

5.
Dent J (Basel) ; 11(12)2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38132418

ABSTRACT

AIM: Polydeoxyribonucleotide (PDRN) is a chain-like polymer derived from DNA. Recent in vitro and animal studies have showcased the beneficial impacts of PDRN on the process of bone mending, whether used on its own or in conjunction with other substances that aid in regeneration. This scoping review aims to synthesize the current understanding of how PDRNs influence bone healing. MATERIALS AND METHODS: The studies included in the screening procedure were randomized controlled clinical trials (RCTs), both retrospective and prospective case-control studies, as well as in vitro and in vivo investigations. Articles were sourced from PubMed (MEDLINE), Scopus, EMBASE, Web of Science, and Google Scholar electronic databases using the following MeSH terms: (polydeoxyribonucleotide) and (bone) and (regeneration). RESULTS: Initially, 228 articles were identified. Following the review process, a total of eight studies were ultimately examined. Among these, two were confined to laboratory studies, five were conducted on living organisms, and one encompassed both evaluations on living organisms and in vitro assessments. A descriptive qualitative approach was employed to present the data extracted from the studies that were included. CONCLUSIONS: PDRN has the potential to enhance the process of bone healing and the quantity of newly generated bone when combined with grafting materials. Future clinical studies are warranted to ascertain the appropriate clinical application of PDRN based on the dosage under consideration.

6.
Dent J (Basel) ; 11(11)2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37999020

ABSTRACT

This technical note aims to present a recently developed computer-guided protocol characterized by titanium-reinforced stackable surgical guides during post-extractive implant placement and subsequent immediate loading. A full maxillary edentulism was rehabilitated with one-piece implants, starting from a pre-existing removable denture. 3D digital scans of the removable denture and upper and lower arches were performed. On this basis, a prototype with ideal esthetic and functional outcomes was realized and replicated into a custom-made radiological stent with markers. The superimposition of STL and DICOM files allowed virtual planning of one-piece implants in the ideal prosthetically driven position. The stackable guides, composed of a fixed base template and additional removable components, were then realized. The fixed template, initially secured with anchor pins to the bone, was no longer removed. The removable components, which were screwed to the base template, were used to perform implant surgery and immediate prosthetic loading. No surgical complications occurred, the implants achieved a minimum insertion torque of 35 Ncm, and immediate prosthetic loading was performed. The base template allowed for the maintenance of a fixed reference during the entire workflow, improving the transition between the digital project, the surgical procedure, and the prosthetic rehabilitation.

7.
J Clin Med ; 12(15)2023 Aug 03.
Article in English | MEDLINE | ID: mdl-37568499

ABSTRACT

The present pilot study was designed by hypothesizing a possible correlation between lack of accuracy in implant placement and peri-implant hard and soft tissue health. A total of five patients underwent computer-guided implant surgery and full-arch immediate loading between 2013 and 2014. They subsequently underwent postoperative cone-beam computed tomography (CBCT). After a follow-up of 5 years, all patients were recalled for a clinical-radiographic evaluation of peri-implant health status. The mean linear deviation was 0.5 ± 0.2 mm at the implant's head and 0.6 ± 0.2 mm at the implant's apex, while the mean angular deviation of the long axis was 2.8° ± 1.2°. A mean marginal bone loss (MBL) of 1.16 ± 0.94 mm and 2.01 ± 1.76 mm was observed after 1 and 5 years of follow-up, respectively. At 5 years, the mean peri-implant probing depth (PPD) was 4.09 ± 1.44 mm, 66.6% of the evaluated implants showed peri-implant bleeding on probing (BOP), keratinized mucosa (KM) was <2 mm in 48.4% of cases, and mucosal recession (REC) ≥ 1 mm was assessed in 45.4% of the included implants. A negative correlation was observed between bucco-palatal/lingual linear inaccuracy and MBL, PPD, BOP, and KM.

8.
Int J Implant Dent ; 9(1): 10, 2023 04 12.
Article in English | MEDLINE | ID: mdl-37043147

ABSTRACT

PURPOSE: The aim of the present study was to evaluate the long-term effectiveness of a xenogeneic collagen matrix (CM) in pre-prosthetic augmentation of the keratinized mucosa width (KMW) at implant sites. METHODS: All of the patients with localized implant-supported rehabilitation previously treated with vestibuloplasty and KMW augmentation with a non-cross-linked porcine CM were recalled. KMW was measured clinically in an apico-coronal direction from the mucogingival junction to the mucosal margin at the prosthetic zenith of each crown. Measurements were performed clinically by means of a PCP-UNC15 periodontal probe and rounded to the nearest mm. KMW values recorded at 1 year, 5 and 10 years from the soft tissue augmentation procedure were compared using a one-way repeated-measures ANOVA with Bonferroni multiple comparison post-hoc analysis. The level of significance was set at 0.05. RESULTS: Measurements were conducted on 13 patients. All implants were in function with no signs of biological complications. All except one implant site showed KMW ≥ 2 mm. KMW decreased significantly from 1 year (3.33 ± 1.11 mm) to 5 years (2.77 ± 0.92 mm) (p = 0.001), and finally remained stable from 5 to 10 years (3.2 ± 0.99 mm) (p = 0.607). From a visual aspect, peri-implant soft tissues were characterized by a good texture and color blending compared to the adjacent teeth, highlighting good integration of the remodeled tissues and stability of the esthetic result. CONCLUSIONS: The use of a CM in pre-prosthetic soft tissue augmentation at implant sites has proven to be effective in obtaining and maintaining at least 2 mm of KMW around dental implants over a follow-up of 10 years.


Subject(s)
Dental Implants , Animals , Swine , Prospective Studies , Follow-Up Studies , Esthetics, Dental , Mucous Membrane , Collagen/therapeutic use
9.
J Oral Implantol ; 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36473182

ABSTRACT

The aim of the present study was to analyze the survival and success rates of dental implants placed in atrophic alveolar ridges reconstructed with mandibular symphysis autogenous onlay bone grafts, with a 20-year follow-up. A sample of five patients referred to the authors' department between 2000 and 2001 seeking for an implant-supported fixed rehabilitation. Patients were treated by means of autogenous bone blocks grafted from the mandibular symphysis and covered with bone substitutes (DBB) and a resorbable membrane. Then delayed implants were placed and finally prosthetic restoration was performed. In total, 10 implants placed in 5 patients were evaluated with a follow-up of 20 years. Both implant survival and success rate were 100%. The mean marginal bone loss was 0.32  [[EQUATION]]  0.39 mm (range 0-1.3 mm). Considering the conditions of peri-implant hard and soft tissues, the diagnosis of peri-implant health was made for all the implants included. According to this study, implants placed in alveolar ridges augmented by means of autogenous chin bone grafts showed long-term survival and high success rates. A correct management of peri-implant soft tissues and an accurate prosthetic rehabilitation are also fundamental to obtain the durable success of the treatment.

10.
Int J Oral Maxillofac Implants ; 37(2): 250-269, 2022.
Article in English | MEDLINE | ID: mdl-35476854

ABSTRACT

PURPOSE: The exposure of nonresorbable membranes following alveolar bone augmentation is one of the most frequently occurring complications. This review aimed to investigate the treatments that can be adopted to manage the exposure of polytetrafluoroethylene-based membranes (PTFE-ms) and titanium meshes (TMs) and their outcomes. MATERIALS AND METHODS: Two independent reviewers electronically and manually searched the EMBASE, PubMed/MEDLINE, Scopus, and Cochrane bibliographic databases to retrieve pertinent articles available between January 2000 and March 2021. Only human studies describing the type of treatment and the soft tissue outcome following exposure of PTFE-ms or TMs were included. RESULTS: Overall, 11 articles in the PTFE-ms group and 24 in the TM group were included for data analysis. Results indicated that, in both groups, two distinct therapeutic strategies are mostly applied in case of exposure, namely, pharmacologic and mechanical treatments. Other options have been identified seldomly. Statistically significant evidence of an association between the type of barrier membrane and the exposure rate (28.7% vs 38.5% for TMs and PTFE-ms, respectively; P = .019) and between the type of exposed device and the treatment outcome in terms of removal rate following therapy (11.9% and 44.4% for TMs and PTFE-ms, respectively; P < .001) was noted. CONCLUSION: In both groups, chlorhexidine applications and meticulous plaque control may lead to improved healing conditions after exposure. Surgical removal of the exposed portion can be considered to promote secondary intention healing. The beneficial effects of systemic antibiotics could not be demonstrated in the management of the exposure but should be evaluated in case of graft infection.


Subject(s)
Alveolar Ridge Augmentation , Dental Implants , Alveolar Ridge Augmentation/adverse effects , Alveolar Ridge Augmentation/methods , Bone Regeneration , Humans , Polytetrafluoroethylene , Surgical Mesh/adverse effects , Titanium
11.
Photodiagnosis Photodyn Ther ; 37: 102598, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34699984

ABSTRACT

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is used in endodontics to improve orthograde root canal disinfection as an adjunct to standard treatments. Conversely, evidence concerning the application of aPDT in retrograde endodontic surgery is limited. Thus, the aim of the present study was to provide additional data regarding the use of aPDT in the surgical endodontic treatment of periapical lesions. METHODS: A total of 25 consecutive patients presenting teeth with periapical radiolucency eventually associated with clinical signs and symptoms of apical periodontitis were included. Following access flap completion, osteotomy, mechanical debridement, root apical third resection, and preparation of the root-end cavity, aPDT was applied to decontaminate the surgical site using phenothiazine chloride dye at a concentration of 10 mg/mL and irradiation with a hand-held 100-mW diode laser with a wavelength of 660 ± 10 nm. At the latest follow-up visit, healing was evaluated as successful, uncertain, or failure according to well-established clinical and radiological criteria. RESULTS: Overall, 31 periapical lesions were treated with aPDT. Healing proceeded uneventfully. The mean follow-up time was 36.19 months, with times ranging from 12 to 85 months. A total of 25 (80.65%) cases were classified as successful, 5 (16.13%) as uncertain, and only one (3.22%) as failure. Irrespective of the treatment outcome, all treated teeth were still functional, with no symptoms reported by the patients. CONCLUSION: aPDT as an adjunctive treatment modality in the surgical endodontic treatment of periapical lesions showed promising medium-term results associated with preservation of all diseased teeth.


Subject(s)
Anti-Infective Agents , Periapical Periodontitis , Photochemotherapy , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/therapeutic use , Humans , Periapical Periodontitis/drug therapy , Periapical Periodontitis/surgery , Photochemotherapy/methods , Root Canal Therapy/methods
12.
J Clin Med ; 10(23)2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34884228

ABSTRACT

OBJECTIVES: A wide variety of approaches have been proposed to manage anticoagulant drugs in patients undergoing dental surgery; vitamin K antagonists and novel direct oral anticoagulants have been used. The present study aims to explore the existing evidence concerning the management of patients in anticoagulant therapy undergoing oral surgery procedures and to give suggestions related to peri- and post-operative measures. MATERIALS AND METHODS: A comprehensive search of databases was conducted to identify studies that evaluated the relationship between direct oral anticoagulants and dental procedures. The present scoping review was realized in adherence with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The publications varied from randomized controlled trials (RCT) to cohort trials. Only articles written in English language and published between 2000 to 2020 were screened. The studies were included if discussing the management of a patient in anticoagulant therapy (warfarin or direct oral anticoagulants) scheduled for tooth extraction. RESULTS: 33 studies were selected and included in the qualitative review. Nineteen considered anticoagulant therapy with warfarin, six considered anticoagulant therapy with new oral anticoagulants and eight compared patients taking warfarin with patients taking direct oral anticoagulants. CONCLUSIONS: No case of extractive surgery should alter the posology of the drug: thromboembolic risks derived from discontinuation are heavier than hemorrhagic risks. CLINICAL RELEVANCE: direct oral anticoagulants are safer in terms of bleeding and manageability and bleeding episodes are manageable with local hemostatic measures.

13.
J Maxillofac Oral Surg ; 20(3): 381-388, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34408364

ABSTRACT

AIM: The present study evaluated the clinical and radiological stability of hard and soft tissues following alveolar socket preservation (ASP) procedure with a follow-up of 5 year from implant insertion. MATERIALS AND METHODS: The initial sample consisted of seven patients who underwent single tooth extraction and ASP procedure by means of demineralized bovine bone mineral particles covered with a porcine-derived non-cross-linked collagen matrix (CM). Each patient received a submerged single implant in the healed site. Mesial and distal peri-implant marginal bone resorption (MBR) rates were assessed radiographically at 1 year (T 1) and 5 years (T 2) after implant placement (baseline value). RESULTS AND STATISTICS: No dropouts occurred up to 5 years. At T 1, the MBR was 0.08 ± 0.16 mm at the mesial aspect and 0.1 ± 0.12 mm at the distal aspect. This difference was not statistically significant (P = 0.867). At T 2, the mesial MBR was 0.15 ± 0.17 mm and the distal MBR was 0.11 ± 0.14 mm, with a non-statistically significant difference (P = 0.532). Therefore, no statistically significant differences were detected comparing mesial and distal MBR at any time point. With respect to the intra-group comparisons, no differences were observed comparing the different study periods within each variable. Indeed, the comparison between T 0, T 1 and T 2 was non-statistically significant at both mesial (P = 0.06) and distal (P = 0.06) aspects. After 5 years, the volume of the soft tissues appeared clinically well maintained with a natural aspect around dental implants and adjacent teeth. CONCLUSION: ASP using demineralized bovine bone mineral in combination with CM proved to be an effective technique to maintain stable dimensional volumes of both hard and soft tissues.

14.
Article in English | MEDLINE | ID: mdl-33528448

ABSTRACT

The aim of this article is to propose a simplified digital protocol for the treatment of the fully edentulous patient, using an immediate implant and immediate loading protocol to deliver a polymethyl methacrylate metal-reinforced hybrid prosthesis. Ten consecutive patients were treated with this approach. At the end of 1 year, there was an implant survival rate of 97.8% and a prosthetic success rate of 100%. Based on the responses to the quality of life questionnaire, patients had a high acceptance rate for this treatment protocol. Within the limits of this case series, the proposed simplified digital protocol could be utilized for reconstruction in the fully edentulous patient and for delivering an implant-supported prosthesis immediately after implant placement.


Subject(s)
Dental Implants , Immediate Dental Implant Loading , Jaw, Edentulous , Mouth, Edentulous , Dental Implantation, Endosseous , Dental Prosthesis, Implant-Supported , Follow-Up Studies , Humans , Jaw, Edentulous/surgery , Mouth, Edentulous/surgery , Quality of Life , Treatment Outcome
15.
J Dent Sci ; 16(1): 333-341, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33384817

ABSTRACT

BACKGROUND/PURPOSE: The existing literature lacks information regarding the use of digital workflows during pre-surgical planning of implant rehabilitations in resorbed edentulous ridges. Thus, the aim was to evaluate the effectiveness of computer-guided implant placement and simultaneous computer-aided guided bone regeneration (GBR) in the treatment of atrophic posterior alveolar ridges. MATERIALS AND METHODS: Partially edentulous patients requiring GBR simultaneously to implant insertion were enrolled. Implant positions and the augmented missing bone were planned with specific software. A stereolithographic model of the grafted jaw was produced to transfer the virtual bone augmentation to the surgical field. A tooth-supported stent was used to guide implant insertion according to the virtual project. Visual analogue scales (VASs) were used to self-register postoperative pain, swelling, bleeding, and perception of the operation. Post-operative cone-beam computed tomography scan was superimposed to the virtual project to evaluate the accuracy of implant positions. RESULTS: Overall, 10 implants were placed in 5 patients. Healing proceeded uneventfully in all except one patient that showed a dehiscence of the lingual flap as early surgical complication. Nevertheless, complete filling of the bone defects was observed clinically and radiographically in all patients. Pain scored exceptionally high with respect to the other variables. Deviations of 0.73 ±â€¯0.21 mm, 0.59 ±â€¯0.28 mm, and 3.05°â€¯±â€¯1.22° were found at implant head, apex, and long-axis respectively. Distal implants showed higher angular deviations compared to mesial implants (p = 0.008). CONCLUSION: Computer-guided approach provided encouraging results in terms of efficacy and accuracy. Conversely, patient-centered outcomes were below the expectations.

16.
J Prosthet Dent ; 125(2): 197-203, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32087844

ABSTRACT

Digitalization of edentulous areas restored with dental implants is still considered a demanding procedure, mainly because of the lack of fixed reference landmarks, together with an increased interimplant distance. To overcome such limitations, an auxiliary device is introduced with the 3-fold purpose of stretching the soft tissues with a fixed object connected to the scan bodies, creating areas with nonhomogeneous architectures between the implants, and shortening the interimplant distance with the interposition of solid geometric figures. The rationale was to increase the accuracy of digital scans in a cast-free digital implant workflow.


Subject(s)
Dental Implants , Mouth, Edentulous , Computer-Aided Design , Dental Prosthesis, Implant-Supported , Humans , Mouth, Edentulous/diagnostic imaging , Workflow
17.
Protoplasma ; 258(1): 71-85, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32918205

ABSTRACT

Aldrovanda vesiculosa (Droseraceae) is a rare aquatic carnivorous plant, distributed in Europe, Asia, Africa, and Australia. Aldrovanda populations can flower prolifically under favourable conditions, but seed set is very limited. We studied the structure of Aldrovanda pollen collected from flowers in different developmental stages (opened and non-opened anthers) from both European and Australian populations to elucidate pollination traits and the basis of poor seed set on the basis of microscopic observation of pollen and anther structure. Microscopic analyses of Aldrovanda pollen showed that this plant has pollen arranged in tetrads like other species in the Droseraceae family. In hydrated pollen, cytoplasmic protrusions originate from pores located along the equatorial wall of monads, and can develop into pollen tubes. Interestingly, pollen development from microspores occurs in open anthers, suggesting a delay of the developmental stages. In addition, pollen development displays altered sperm cell formation and precocious pollen germination. Precocious germination may characterize recalcitrant pollen, which naturally do not undergo dehydration before anthesis and remain partially hydrated, particularly in aquatic and wetland plants. These alterations of male gametophyte development could affect fertilization processes, and be the reason for the low reproductive capability of Aldrovanda observed both in the field and in cultures. Generally, reduced pollen longevity and very quick germination are considered an adaptation to aquatic or wet environments.


Subject(s)
Carnivorous Plant/chemistry , Droseraceae/chemistry , Germ Cells, Plant/chemistry , Pollen
18.
Materials (Basel) ; 14(1)2020 Dec 28.
Article in English | MEDLINE | ID: mdl-33379326

ABSTRACT

The quality and quantity of peri-implant soft tissues at the crestal portion of dental implants are important aspects to consider for a long-term successful implant-supported rehabilitation. Some relevant factors attributed to the implant health include mucosal thickness and keratinization. In this respect, many techniques and materials have been described to augment and improve buccal peri-implant soft tissues. Over the last few years, newly developed xenogeneic collagen matrices have been introduced in peri-implant plastic surgery to replace autogenous soft tissue grafts; however, data remain controversial so far. Thus, the purpose of the present report was to present a novel surgical technique conceived to augment buccal peri-implant soft tissues in combination with a volume-stable porcine collagen matrix. The rationale and the fundamental concepts that led to the use of a xenogeneic matrix to increase soft tissue volumes were also discussed.

20.
Materials (Basel) ; 13(10)2020 May 22.
Article in English | MEDLINE | ID: mdl-32455919

ABSTRACT

BACKGROUND: bone augmentation by means of manually shaped titanium mesh is an established procedure to regenerate atrophic alveolar ridges and recreate a proper contour of the peri-implant bone anatomy. Conversely, current literature on the use of preformed titanium meshes instead of traditional grids remains lacking. Therefore, the aim of the present prospective study was to evaluate the use of preformed titanium mesh to support bone regeneration simultaneously to implant placement at dehiscence-type defects from clinical, radiological, and patient-related outcomes. METHODS: 8 implants showing buccal dehiscence defects were treated with preformed titanium mesh directly fixed to flat abutments screwed to the implant. Intrasurgical clinical measurements and radiographic evaluations by means of cone-beam computed tomography scans were performed to assess the horizontal bone gain after 8 months from the augmentation surgery. Biological and patient-centered outcomes were also evaluated.; Results: clinically, a mean horizontal bone gain of 4.95 ± 0.96 mm, and a mean horizontal thickness of the buccal plate of 3.25 ± 0.46 mm were found. A mean horizontal bone gain of 5.06 ± 0.88 mm associated with a mean horizontal thickness of the buccal plate of 3.45 ± 0.68 mm were observed radiographically. From a macroscopic aspect, the remodeled graft appeared well integrated with the host bone. Well vascularized newly formed bone-like tissue was observed in intimate contact with the implants. CONCLUSIONS: preformed titanium mesh may be effective in supporting simultaneous horizontal bone regeneration at dehiscence-type peri-implant defects. Titanium mesh exposure still remain an issue in this type of surgery.

SELECTION OF CITATIONS
SEARCH DETAIL
...