Obstetric outcome of teenage pregnancies from 2002 to 2008: the Sheffield experience.

We compared the obstetric outcome of 1,922 teenage pregnant women with a control population of 10,550 women aged 20-39 years. The teenage women had a significantly higher normal vaginal delivery rate (65% vs 45%; RR 1.44, 95% CI: 1.38-1.49; p < 0.001) and a lower operative delivery rate compared with control women (elective caesarean section: 1.7% vs 4.9%, RR 0.347, 95% CI: 0.25-0.49, p < 0.001; emergency caesarean section: 13.3% vs 22.9%, RR 0.58, 95% CI: 0.51-0.65, p < 0.001; instrumental delivery: 19.3% vs 26.3%, RR 0.73, 95% CI: 0.66-0.81, p < 0.001). There was no difference in the pre-term delivery rate or in the stillbirth rate between the two groups. When stratified further, there was no difference in the pre-term delivery rate and low birth weight rate between teenage mothers aged 13-17 years and those aged 17-19 years. Teenage pregnant women have better obstetric performance in terms of mode of delivery without an increased risk of stillbirth or prematurity compared with older women.

Pregnancy outcome in women with factor V Leiden and recurrent miscarriage.

We compared the outcome of 25 untreated pregnancies among women with recurrent miscarriage (RM) at <12 weeks' gestation who were heterozygous for factor V Leiden with women with unexplained RM. The livebirth rate was lower among pregnancies in carriers of factor V Leiden (12/25; 48%) compared with pregnancies in women with unexplained RM (175/307; 57%), but the difference did not reach statistical significance. The best possible treatment regimen to improve livebirth rate in this group of women needs to be assessed in the form of a randomised controlled trial.

Fruit and Vegetable Consumption and Frailty: A Systematic Review.

OBJECTIVE: To identify currently available evidence on fruit and vegetable consumption in association with frailty by conducting a systematic review of the literature and to summarise and critically evaluate it. DESIGN: Systematic review. SETTING: Four electronic databases (Embase, MEDLINE, CINAHL and PsycINFO) were systematically searched in August 2017 for observational cohort studies providing cross-sectional or prospective associations between fruit and vegetable consumption and frailty risks. Additional studies were searched by manually reviewing the reference lists of the included studies and related review papers and conducting forward citation tracking of the included studies. The methodological quality of prospective studies was assessed using the Newcastle-Ottawa scale. PARTICIPANTS: Community-dwelling general populations. RESULTS: A total of 6251 studies were identified, of which five prospective studies with follow-up periods of 2-10.5 years and two cross-sectional studies were included. Among the five prospective studies, three had adequate methodological quality. Because of different measurements and statistical methodologies, a meta-analysis was not possible. The two studies of good quality showed that fruit and vegetable consumption was mostly associated with lower risk of incident frailty. The other study as a sub-analysis retrospectively examined baseline fruit and vegetable consumption of those who developed frailty and those who did not at follow-up and showed no significant associations. CONCLUSIONS: Although good quality studies on this topic are scarce, there is some suggestion that higher fruit and vegetable consumption may be associated with lower frailty risk. More high quality research is needed.

Treatment planning of implants in the aesthetic zone.

Aesthetic restoration of anterior teeth with implant supported restorations is one of the most difficult procedures to execute. Bone resorption following anterior tooth extraction often compromises gingival tissue levels for the implant restoration. In the last 10 years the focus has shifted from osseointegration, to creation of an implant borne restoration which is in harmony with the surrounding hard and soft tissue. Complete reconstruction of tooth and gingival related aesthetics remains the primary objective and in some instances can be very difficult to achieve.

Rationale for dental implants.

The clinical replacement of lost natural teeth by osseointegrated implants has represented one of the most significant advances in restorative dentistry. Two decades ago, a majority of dentists were sceptical about implants and rejected them entirely. Today it is rare to find a practitioner who does not work with dental implants or who is not actively participating in one of the many seminars or courses offered by universities, professional societies and implant manufacturers.

Treatment planning of implants in posterior quadrants.

Differences in anatomy and biomechanics make treatment of posterior quadrants with dental implants substantially different to that of anterior areas. Without implants, when posterior teeth were lost, treatment options included a long span fixed partial denture or a removable prosthesis, especially when no terminal abutment was available. Today, with the use of implants, options are available that allow preservation of unrestored teeth.(1) When teeth are missing, implant supported restorations can be considered the treatment of choice from the perspective of occlusal support, preservation of adjacent teeth and avoidance of a removable partial denture.

Designing abutments for cement retained implant supported restorations.

In another article in this series the authors' preference for screw retained implant supported restorations was presented together with a literature review and rationale.(1) There remain situations when screw retention is not possible due to implant position, implant trajectory, aesthetics or function.

Connecting implants to teeth.

Osseointegrated implants have proven to have a high degree of success in the edentulous arches. This success has been replicated in partially edentulous arches. When natural teeth are present, it can be tempting to fabricate restorations using support from both implants and natural teeth. The mechanism of attachment and the perceived problem of the differential support provided by the implant and the tooth have been discussed by many authors.

Screw versus cemented implant supported restorations.

Implant supported restorations can be attached to implants with screws or can be cemented to abutments which are secured to implants with screws. Screw retained implant restorations are the authors' preferred method of securing restorations to implants. This article will be written from this perspective and the advantages and disadvantages of each method of retention will be discussed under the following headings: Aesthetics, Retrievability, Retention, Implant placement, Passivity, Provisionals, Occlusion, Immediate loading, Impression procedures, Long term treatment planning.

Treatment planning of the edentulous mandible.

Edentulism can be a debilitating handicap. Zarb described endentulous individuals who could not function as 'denture cripples'.(1) Most difficulty with complete denture prostheses arises from the inability to function with the mandibular prostheses. Factors that adversely affect successful use of a complete denture on the mandible include: 1) the mobility of the floor of the mouth, 2) thin mucosa lining the alveolar ridge, 3) reduced support area and 4) the motion of the mandible (Figs 1,2). These factors alone can explain the difficulty of wearing a denture on the mandibular arch compared to the maxillary arch. The maxilla exhibits much less mobility on the borders of the denture than the mandible, moreover having a stable palate with thick fibrous tissues available to support the prostheses and resist occlusal forces. These differences explain most of the reasons why patients experience difficulty with using a complete denture on the mandibular arch compared to the maxillary arch.

Impression techniques for implant dentistry.

The object of making an impression in implant dentistry is to accurately relate an analogue of the implant or implant abutment to the other structures in the dental arch. This is affected by use of an impression coping which is attached to the implant or implant abutment. This impression coping is incorporated in an impression - much as a metal framework is 'picked up' in a remount impression for fixed prosthodontics. With implant copings the coping is usually attached to the implant or abutment with screws. The impression material used is usually an elastomeric impression material; the two types most widely used and shown to be the most appropriate are polyether and polyvinyl siloxane impression materials.

Treatment planning of the edentulous maxilla.

The predictability of successful osseointegrated implant rehabilitation of the edentulous jaw as described by Branemark et al., introduced a new era of management for the edentulous predicament. Implant rehabilitation of the edentulous maxilla remains one of the most complex restorative challenges because of the number of variables that affect both the aesthetic and functional aspect of the prosthesis. Among the prosthesis designs used to treat the edentulous maxilla are fixed or removable implant-supported restorations. Since the aesthetic requirements and preoperative situation of each patient varies, considerable time must be spent on accurate diagnosis to ensure patient desires are satisfied and predictable outcomes are achieved. The purpose of this article is to compare the treatment options and prosthesis designs for the edentulous maxilla. Emphasis will be placed on diagnosis and treatment planning. Criteria will be given to guide the practitioner in deciding whether a fixed or removable restoration should be placed. This objective will be accomplished through the review of cases with regard to varying design considerations and factors that influence the decision-making process.

Failures in implant dentistry.

This article describes the many failures and complications that can occur when using implants to support restorations. Most of these failures can be prevented with proper patient selection and treatment planning. Implant failures can be largely classified into four main categories: 1) loss of integration, 2) positional failures 3) soft tissue defects, and 4) biomechanical failures. Each of these will be discussed with examples to illustrate the problem.

An interdisciplinary approach to treatment planning in implant dentistry.

The practice of implant dentistry requires an interdisciplinary approach that integrates the knowledge, skills and experience of all the disciplines of dentistry into a comprehensive treatment plan. This article outlines a comprehensive interdisciplinary treatment philosophy designed for developing the foundation of optimal aesthetics in implant dentistry. Cases are presented to illustrate the utility of interdisciplinary treatment in which specialists are recruited to enhance and improve a patient's dental function and aesthetics.

Factors that affect individual tooth prognosis and choices in contemporary treatment planning.

A clinician evaluates a tooth for its quality of health. Once accomplished an estimate of longevity and survival is estimated. With current knowledge about the survival and success of implants a decision is made as to whether to extract or to treat and maintain the tooth. Questions and doubts abound in the decision making process in regards to the prognosis of an individual tooth. Unfortunately in dentistry, as in all biologic sciences, there are no straightforward answers to questions. This article will attempt to review the literature in this area to aid the practitioner in the decision making process with regards to the compromised tooth. The article will focus on the single tooth or implant restoration. Other factors such as the strategic value of a tooth and financial limitations in relation to long-term prognosis will also be discussed.

Transitioning patients from teeth to implants.

One major obstacle to treatment with implants is the transitional phase between a tooth supported occlusion and an implant supported occlusion. This is of particular concern when a patient with a failing dentition has not worn a removable prosthesis before and is planning to have a reconstruction supported by implants.

The role of orthodontics in implant dentistry.

Orthodontic treatment of partially edentulous patients is difficult, especially if a significant number of teeth are missing. With loss of teeth, adjacent or opposing teeth usually tip, drift or over-erupt leaving spaces that are not optimal for replacement of missing teeth. Orthodontic correction of these spatial relationships will aid prosthetic replacement of the missing teeth, function, hygiene and aesthetics. Orthodontists rely on teeth to provide the anchorage to correct malocclusions. With patients with an intact dentition dental anchorage is usually adequate to facilitate tooth movement. In some partially edentulous patients however, insufficient anchorage may present to correct the malocclusion. In these patients implants can provide additional anchorage. At times, osseointegrated implants can also be used to support restorations after completion of orthodontic therapy if treatment planning is precise. The use of implants for orthodontic anchorage requires an interdisciplinary approach and precise planning to achieve optimal results.

Genetic thrombophilic mutations among couples with recurrent miscarriage.

BACKGROUND: Some cases of recurrent first trimester miscarriage (RM)-the loss of three or more consecutive pregnancies at <12 weeks' gestation-have a thrombotic aetiology. METHODS: We determined (i) the prevalence of three thrombophilic mutations [factor V Leiden (FVL), prothrombin G20210A (PTG) and methylenetetrahydrofolate reductase (MTHFR) C677T] amongst 357 Caucasian couples with RM and 68 parous Caucasian couples with no history of miscarriage and (ii) the prospective outcome of untreated pregnancies amongst couples with RM in which either partner carried a thrombophilic mutation. RESULTS: The allele frequencies of FVL (2%), PTG (2%) and MTHFR C677T (31%) were similar between cases and controls. The prevalence of multiple thrombophilic mutations (greater than one mutation) was also similar between cases and controls. Amongst couples in whom either partner carried greater than one thrombophilic allele, the relative risk of miscarriage in a future untreated pregnancy was 1.9 (95% confidence interval, 1.3-2.8) compared with those couples who carried no thrombophilic mutation. CONCLUSION: The prevalence of thrombophilic mutations is similar in couples with RM and parous controls. In couples with RM, multiple genetic thrombophilic mutations in either partner significantly increases the risk of miscarriage in a subsequent pregnancy.

Insulin regulation of glucose-6-phosphate dehydrogenase gene expression is rapamycin-sensitive and requires phosphatidylinositol 3-kinase.

Glucose-6-phosphate dehydrogenase (G6PDH) controls the flow of carbon through the pentose phosphate pathway and also produces NADPH needed for maintenance of reduced glutathione and reductive biosynthesis. Hepatic expression of G6PDH is known to respond to several dietary and hormonal factors, but the mechanism behind regulation of this expression has not been characterized. We show that insulin similarly induces expression of endogenous hepatic G6PDH and a reporter construct containing 935 base pairs of the G6PDH promoter linked to luciferase in transient transfection assays. Using well tested and structurally distinct inhibitors of Ras farnesylation, lovastatin and B581, and a specific inhibitor of mitogen-activated protein kinase kinase activation, PD 98059, we show that the Ras/Raf/mitogen-activated protein kinase pathway is not utilized for the insulin-induced stimulation of G6PDH gene expression in primary rat hepatocytes. Similarly, using well characterized inhibitors of phosphatidylinositol 3-kinase, wortmannin and LY 294002, we show that PI 3-kinase activity is necessary for the induction of G6PDH expression by insulin. Rapamycin, an inhibitor of FRAP protein, which is involved in the activation of pp70 S6 kinase, blocks the insulin induction of G6PDH, suggesting that S6 kinase is also necessary for the insulin induction of G6PDH expression.