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Abandoned river channels on alluvial floodplains represent dynamic systems where sediments, organic matter, and pollutants preferentially accumulate during extreme discharge events. Descriptive models that explain the infilling of these floodplain lakes due to sedimentation processes recognize different stages in their evolution. For example, the threshold for hydrologic connectivity and the transfer of material increases in older lakes as a plug-bar develops. Sedimentary archives collected from floodplain lakes are widely used to reconstruct ecological and hydrologic dynamics in riverine settings, but how floodplain lake evolution influences flow velocities and sedimentation patterns on an event scale remains poorly understood. In this study, we examine a floodplain lake along the Trinity River at Liberty during the extreme flood event associated with the landfall of Hurricane Harvey in August 2017. We combine sediment samples collected in and around a floodplain lake with hydraulic modeling simulations in the HEC-RAS modeling platform from the US Army Corps of Engineers to examine inundation, flow velocity, and sedimentation patterns. Additionally, we develop a series of alternative lake bathymetries to study the influence of floodplain lake evolution on flow velocity patterns during the flood. The hydraulic model reproduces the sediment patterns that we observe around the lake resulting from Hurricane Harvey and matches descriptive models on the behavior of a young floodplain lake. We find that sediments deposited in the lake following the Hurricane Harvey flood become thinner and finer with distance from the lake entrance in accordance with simulated flow velocities that are lower further from the lake entrance. Flow velocity simulations from model runs with alternative plug-bar geometries and lake depths imply that sedimentation patterns will shift as the lake evolves and infills. As the floodplain lake becomes shallower and narrower, flow velocities extend further into the lake resulting in more extensive transport of coarse-grained material into the lake. These simulations are coherent with observed sediment records from lakes in different stages of floodplain lake evolution. The integration of sediment sampling and hydraulic model simulations provides a method to understand the processes that govern sedimentation in floodplain lakes during flood events that will improve interpretations of individual events in sedimentary archives from these contexts.

The expansion of implant support for partially edentulous and single tooth indications over the past 30 years has been remarkable, and usage of implants has changed to include more intact sites, placement at time of tooth extraction, and single tooth restoration. The use of short implants is evolving with these treatment applications (Fig. 4.1).

Per-Ingvar Branemark’s observation of bone fusing to a titanium surface in 1959 led to early evaluation as potential anchorage within bone for both loadbearing and passive prosthetic applications. Simultaneous research investigations within orthopedic, hand, ENT, and plastic surgery were all parallel to applications within dentistry and specialties for intraoral and extraoral maxillofacial anchorage solution potential. For the patient with unsolvable denture problems due to a highly resorbed maxilla and/or mandible, rehabilitation with a fixed, fully implant supported restoration was established in the 1970s as a routine treatment [1] (Fig. 3.1).

Purpose: The sequence of observations presented is intended to alert the dental profession to complications that may occur when teeth and implants co-exist and subtle adult craniofacial growth occurs. Materials and Methods: The authors’ observations of partially edentulous implant restorations with more than 20 years of follow-up included some observed changes relative to patients’ remaining teeth and jaw structures. These changes, which were not easily explained and appeared to be random deviations from expected implantrestorative stability, conformed with research ! ndings of craniofacial growth continuing into adulthood. The authors identi! ed several distinct areas in which such adult craniofacial growth could potentially in" uence the relationship of implant restorations to the remaining teeth and jaw structure. Results: Potential esthetic, occlusal, and periodontal rami! cations of continued adult craniofacial growth were found to include changes in occlusion, opened contact as a result of teeth migration, and changes in anterior esthetic results. The latter may include labialization of the anterior implant restoration and a progressive discrepancy of the cervical gingival margin of the implant restoration relative to the adjacent teeth. Cases are presented showing poor sequellae of treatment due to growth occurring after the assumption was made that a stable jaw dimension had been reached. While continued adult craniofacial growth suf! cient to cause clinical problems is not common, it is also presently not predictable. Conclusion: When changes in tooth position relative to implant restorations secondary to long-term adult growth occur, they can cause problems that are dif! cult or even impossible to correct. Future research will ideally enable identi! cation of patients at risk for developing such problems. INT J ORAL MAXILLOFAC IMPLANTS 2012;28:163‐169. doi: 10.11607/jomi.2827

Purpose Posterior maxillary tilted implants are gaining prevalence as an alternative to sinus grafts supporting fixed maxillary restorations. This paper reports long-term results after loading using this technique. Materials and Methods Consecutive patients presenting for either routine hygiene maintenance or unplanned emergency care who had received tilted implants as a sinus graft alternative to support fixed fully implant-supported restoration of an edentulous maxilla and were followed for a minimum of 10 years from initial implant placement were included in this evaluation. Results Forty-four patients were identified: 40 with bilateral tilted implants and 4 with one tilted and one axial posterior implant. Eight patients received one-piece fixed porcelain-to-gold screw-retained restorations, and thirty-six patients received a fully implant-supported patient-removable Marius Bridge. Seventy-nine out of 84 originally loaded posterior tilted implants survived a minimum of 10 years loading; one tilted implant was lost at 10 years. Eight additional posterior implants were placed for either these lost tilted posterior implants or as proactive supplemental support; one of these replacement tilted implants survived for at least 10 years and is included in the data. All patients have maintained continuous fixed function throughout the follow-up period. Forty-one out of 44 patients continue with the original restoration, 33 without modification or removal of the fixed restoration or implant-connecting bar. One porcelain-to-gold and seven Marius Bridges had framework modifications to accommodate additional implants; 3 Marius Bridge restorations were replaced with a newer generation. Conclusion Within the limits of this retrospective study, the results show that continuous fixed function of fully implant-supported maxillary restorations using posterior tilted implants in terminal positions of support as a sinus graft alternative combined with axial anterior implants is possible over a prolonged period. Loss of a posterior tilted implant after loading is treatable with another tilted, zygomatic or axial implant, typically requiring only modification of the fixed restoration.

Purpose: With the increasing popularity and publication of loading implants at the time of placement, including at time of dental extraction and simultaneous with reconstructive procedures, the objective was to evaluate known variables identified for a traditional unloaded healing period and determine the applicability of these variables to immediate loading. Materials: A total of 124 published reports available as of January 2008 that contained information about loading from the time of surgery up to 3 months postsurgically were examined in light of published variables affecting osseointegration based on a 2 stage surgical approach. Methods: The articles were examined to differentiate between immediate loading (within the initial 48 hours) and early/delayed loading of implants. Success or survival criteria were noted, and where reasons for failure were available, categorized according to six variables considered as determinants for maintaining a long-term bone-to-implant contact. Results: Approximately 60 of the 124 reports described immediately loading implants within 48 with single-tooth, partial, and full-arch restorations, as well as implant overdentures. The implant success or survival rates ranged from 70.8% to 100%. Most studies considered implant survival to be the only criterion for success. Conclusions: Of six parameters identified in 1981 as influencing osseointegration, two parameters (the status of the bone/implant site and implant loading conditions) appear to have diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may affect immediate loading positively or adversely.

Immediate loading of dental implants has become a widely reported practice with success rates ranging from 70.8% to 100%. Although most studies have considered implant survival to be the only measure of success, a better definition includes the long-term stability of the hard and soft tissues around the implant(s) and other adjacent structures, as well as the long-term stability of all the restorative components. The parameters identified in 1981 by Albrektsson and colleagues as influencing the establishment and maintenance of osseointegration have been reconsidered in relation to immediate loading to improve the chances of achieving such success. Two of the six parameters (status of the bone/implant site and implant loading conditions) have preoperative diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may compensate for less-than-ideal site and loading conditions. Factors affecting the outcome of immediate loading are reviewed to assist clinicians attempting to assess its risks and benefits.

This article reports on the efficacy of a technique involving expansion of edentulous ridges of less than 3 mm in width by means of a planned green stick fracture of the labial plate and simultaneous implant placement without the need for membranes. This retrospective case series includes long-term results from 21 patients with 36 sites and 37 implants with a mean follow-up of 4 years, 5 months from the date of restoration. Freeze-dried bone allograft was used in 22 sites (61%) to augment the ridge. Reentry at stage-two surgery confirmed the preservation of the displaced labial plate after implant integration. Three implants were removed prior to the planned uncovering because of incomplete healing of the overlying gingival tissue; therefore, the survival rate of the labial advancement was 92%. No implants failed after definitive prosthetic loading; therefore, the cumulative survival rate of loaded implants was 100%. No significant bone loss was detected at the final follow-up visit. Follow-up after loading ranged from 9 to 148 months. Advancement of the labial plate with simultaneous implant placement to gain horizontal ridge width dimension was shown to be a reliable and practical procedure for single-tooth sites where other grafting methods are often difficult.

With the increasing popularity and publication of loading implants at the time of placement, including at time of dental extraction and simultaneous with reconstructive procedures, the objective was to evaluate known variables identified for a traditional unloaded healing period and determine the applicability of these variables to immediate loading.A total of 124 published reports available as of January 2008 that contained information about loading from the time of surgery up to 3 months postsurgically were examined in light of published variables affecting osseointegration based on a 2 stage surgical approach.The articles were examined to differentiate between immediate loading (within the initial 48 hours) and early/delayed loading of implants. Success or survival criteria were noted, and where reasons for failure were available, categorized according to six variables considered as determinants for maintaining a long-term bone-to-implant contact.Approximately 60 of the 124 reports described immediately loading implants within 48 with single-tooth, partial, and full-arch restorations, as well as implant overdentures. The implant success or survival rates ranged from 70.8% to 100%. Most studies considered implant survival to be the only criterion for success.Of six parameters identified in 1981 as influencing osseointegration, two parameters (the status of the bone/implant site and implant loading conditions) appear to have diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may affect immediate loading positively or adversely.

Immediate loading of dental implants has become a widely reported practice with success rates ranging from 70.8% to 100%. Although most studies have considered implant survival to be the only measure of success, a better definition includes the long-term stability of the hard and soft tissues around the implant(s) and other adjacent structures, as well as the long-term stability of all the restorative components. The parameters identified in 1981 by Albrektsson and colleagues as influencing the establishment and maintenance of osseointegration have been reconsidered in relation to immediate loading to improve the chances of achieving such success. Two of the six parameters (status of the bone/implant site and implant loading conditions) have preoperative diagnostic implications, whereas three (implant design, surgical technique, and implant finish) may compensate for less-than-ideal site and loading conditions. Factors affecting the outcome of immediate loading are reviewed to assist clinicians attempting to assess its risks and benefits.

This retrospective case series presents results from eight patients treated with demineralized freeze-dried bone allograft particles and barrier membranes using either miniscrews or implants to support the membrane in seven patients. In all patients, the amount of vertical bone regeneration enabled placement of one or more implants in the graft sites, followed by loading with definitive prostheses at least 5.5 months after implant placement. Marginal bone heights around the implants have remained stable throughout 4 to 13 years of follow-up.

Background Patients seeking replacement of their upper denture with an implant-supported restoration are most interested in a fixed restoration. Accompanying the loss of supporting alveolar structure due to resorption is the necessity for lip support, often provided by a denture flange. Attempts to provide a fixed restoration can result in compromises to oral hygiene based on designs with ridge laps. An alternative has been an overdenture prosthesis, which provides lip support but has extensions on to the palate and considerations of patient acceptance. The Marius bridge was developed as a fixed bridge alternative offering lip support that is removable by the patient for hygiene purposes, with no palatal extension beyond normal crown-alveolar contours. Purpose Implant-supported restorative treatment of completely edentulous upper jaws, as an alternative to a complete denture, is frequently an elective preference, and it requires significant patient acceptance beyond the functional improvement of chewing. Patients with moderate to severe bone resorption and thin ridges present additional challenges for adequate bone volume and soft-tissue contours. The purpose of this investigation was to develop a surgical and prosthetic implant treatment protocol for completely edentulous maxillae in which optimal lip support and phonetics is achieved in combination with substantial implant anchorage without bone grafting. Materials and methods The Marius bridge is a complete-arch, double-structure prosthesis for maxillae that is removable by the patient for oral hygiene. The first 45 consecutive patients treated by one person (YF) in one center with this concept are reported, with 245 implants followed for up to 5 years after prostheses connection. Results The cumulative fixture survival rate for this 5-year retrospective clinical study was 97%. Five fixtures failed before loading, in five different patients, and two fixtures in the same patient failed at the 3-year follow-up visit. None of the bridges failed, giving a prostheses survival rate of 100%. The complications were few and mainly prosthetic: nine incidences of attachment component complications, one mesobar fracture, and three reports of gingivitis. All complications were solved or repaired immediately, with minimal or no interruption of prostheses use. Conclusions Satisfactory medium-term results of survival and patient satisfaction show that the Marius bridge can be recommended for implant dentistry. The technique may reduce the need for grafting, because it allows for longer implants to be placed with improved bone anchorage and prostheses support. key words: clinical follow-up, complete arch, double structure, esthetics, maxilla, phonetics, tilted implants