In vivo measurement of strain in the periodontal space of pig (Sus scrofa) incisors using in-fiber Bragg sensors.

The incisor teeth in pigs, Sus scrofa, function in association with a disc-shaped snout to explore the environment for potential food. Understanding how mechanical loading applied to the tooth deforms the periodontal ligament (PDL) is important to determining the role of periodontal mechanoreceptors during food exploration and feeding. The objective of this study was to use fiber Bragg (FBG) sensors to measure strain in vivo within the PDL space of pig incisors. The central mandibular incisors of pigs underwent spring loaded lingual tipping during FBG strain recording within the labial periodontal space. FBG sensors were placed within the periodontal space of the central mandibular incisors of ~2-3-month-old farm pigs. The magnitude and orientation of spring loads are expected to mimic incisor contact with food. During incisor tipping with load calibrated springs, FBG strains in vitro (N = 6) and in vivo (N = 6) recorded at comparable load levels overlapped in range (-10-20 µÎµ). Linear regressions between peak FBG strains, that is, the highest recorded strain value, and baseline strains, that is, strain without applied spring load, were significant across all in vivo experiments (peak strain at 200 g vs. baseline, p = .04; peak strain at 2000 g vs. baseline p = .03; peak strain at 2000 g vs. 200 g, p = .004). These linear relationships indicate that on a per experiment basis, the maximum measured strain at different spring loads showed predictable differences. A Friedman test of the absolute value of peak strain confirmed the significant increase in strain between baseline, 200 g, and 2000 g spring activation (p = .02). Mainly compressive strains were recorded in the labial PDL space and increases in spring load applied in vivo generated increases in FBG strain measurements. These results demonstrate the capacity for FBG sensors to be used in vivo to assess transmission of occlusal loads through the periodontium. PDL strain is associated with mechanoreceptor stimulation and is expected to affect the functional morphology of the incisors. The overall low levels of strain observed may correspond with the robust functional morphology of pig incisors and the tendency for pigs to encounter diverse foods and substrates during food exploration.

Cyclic loading failed to promote growth in a pig model of midfacial hypoplasia.

Yucatan miniature pigs, often used as large animal models in clinical research, are distinguished by a breed-specific midfacial hypoplasia with anterior crossbite. Although this deformity can be corrected by distraction osteogenesis, a less invasive method is desirable. We chose a mechanical cyclic stimulation protocol that has been successful in enhancing sutural growth in small animals and in a pilot study on standard pigs. Yucatan minipigs (n = 14) were obtained in pairs, with one of each pair randomly assigned to sham or loaded groups. All animals had loading implants installed on the right nasal and frontal bones and received labels for cell proliferation and mineral apposition. After a week of healing and under anesthesia, experimental animals received cyclic tensile loads (2.5 Hz, 30 min) delivered to the right nasofrontal suture daily for 5 days. Sutural strains were recorded at the final session for experimental animals. Sham animals received the same treatment except without loading or strain gauge placement. In contrast to pilot results on standard pigs, the treatment did not produce the expected sutural widening and increased growth. Although sutures were not fused and strains were in the normal range, the targeted right nasofrontal suture was narrowed rather than widened, with no statistically significant changes in sutural cell proliferation, mineral apposition, or vascularity. In general, Yucatan minipig sutures were more vascular than those of standard pigs and also tended to have more proliferating cells. In conclusion, either because the sutures themselves are abnormal or because of growth restrictions elsewhere in the skull, this cyclic loading protocol was unable to produce the desired response of sutural widening and growth. This treatment, effective in normal animals, did not improve naturally occurring midfacial hypoplasia in Yucatan minipigs.

Understanding Women's Communication with Their Providers During Medication Abortion and Abortion Pill Reversal: An Exploratory Analysis.

Introduction/Objective: Medication abortion is a common experience for women in the United States, now totaling over 50% of all abortions. The purpose of this exploratory analysis is to understand women's medication abortion and abortion pill reversal decision-making experiences, with a particular focus on their communication with their medical providers. Methods: We surveyed women who contacted Heartbeat International to inquire about abortion pill reversal. Eligible women had to complete a minimum of the 2-week progesterone protocol in order to answer the questions on the electronic survey about their medication abortion and abortion pill reversal decisions. We assessed decision difficulty using a Likert scale and provider communication using the Questionnaire on the Quality of Physician-Patient (QQPPI) and analyzed women's narratives about their experiences using thematic analysis. Results: Thirty-three respondents met the eligibility criteria and filled out the QQPPI and decision-difficulty scales. Using the QQPPI scale, women scored their communication with their APR providers as significantly better than their communication with their abortion providers (p < 0.0001). Women reported that choosing medication abortion was significantly more difficult than choosing abortion pill reversal (p < 0.0001). White women, women with college degrees, and women who were not in a relationship with the father of the child reported more difficulty in choosing APR. Conclusion: As the number of women who contact the national hotline to inquire about abortion pill reversal increases, the need to understand the experiences of this growing population of women becomes more salient. This need is particularly important for health care providers who prescribe medication abortion and abortion pill reversal. The quality of the physician-patient interaction is essential to providing effective medical care to pregnant women.

The Effects of Abortion Decision Rightness and Decision Type on Women's Satisfaction and Mental Health.

Background A case series report based on the Turnaway Study has previously concluded that 99% of women with a history of abortion will continue to affirm satisfaction with their decisions to abort. Those findings have been called into question due to a low participation rate (31%) and reliance on a single yes/no assessment of decision satisfaction. Aim To utilize more sensitive scales in assessing decision satisfaction and the associated mental health outcomes women attribute to their abortions. Method  A retrospective survey was completed by 1,000 females, aged 41-45, living in the United States. The survey instrument included 11 visual analog scales for respondents to rate their personal preferences and outcomes they attributed to their abortion decisions. A categorical question allowed women to identify if their abortions were wanted and consistent with their own values and preferences, inconsistent with their values and preferences, unwanted, or coerced. Linear regression models were tested to identify which of three decision scales best predicted positive or negative emotions, effects on mental health, emotional attachment, personal preferences, moral conflict, and other factors relevant to an assessment of satisfaction with a decision to abort. Results Of 226 women reporting a history of abortion, 33% identified it as wanted, 43% as accepted but inconsistent with their values and preferences, and 24% as unwanted or coerced. Only wanted abortions were associated with positive emotions or mental health gains. All other groups attributed more negative emotions and mental health outcomes to their abortions. Sixty percent reported they would have preferred to give birth if they had received more support from others or had more financial security. Conclusions Perceived pressure to abort is strongly associated with women attributing more negative mental health outcomes to their abortions. The one-third of women for whom abortion is wanted and consistent with their values and preferences are most likely over-represented in studies initiated at abortion clinics. More research is needed to understand better the experience of the two-thirds of women for whom abortion is unwanted, coerced, or otherwise inconsistent with their own values and preferences.

Bilateral treatment of the masseter with botulinum toxin: Consequences for mastication, muscle force and the mandibular condyle.

BACKGROUND: Clinical use of botulinum neurotoxins (BoNTs) in masticatory muscles is usually bilateral, but most studies on the functional consequences of BoNT treatment have used unilaterally treated animals. OBJECTIVES: To test the hypothesis that bilateral BoNT treatment of the rabbit masseter hampers mastication and to assess its effects on bone density of the mandibular condyles. METHODS: Ten 5-month-old female rabbits received injections of BoNT into both masseter muscles and nine sham animals received saline. Body weight, incisor bite force during masseter tetany, and surface and fine-wire electromyography (EMG) of the masseter and medial pterygoid muscles were assessed at regular intervals. Half the sample was terminated after 4 weeks and the remainder after 12 weeks. Muscles were weighed and mandibular condyles were scanned with microCT to analyse bone density. RESULTS: BoNT rabbits lost weight and required a soft-food diet. Incisor occlusal force plummeted after BoNT injection and remained lower than the shams. The duration of masticatory cycles was increased in the BoNT rabbits for 5 weeks, with most of the increase due to the adductor burst. Masseteric EMG amplitude began to improve at Week 5, but remained low on the working side throughout the experiment. At the 12-week endpoint, masseter muscles were smaller in the BoNT rabbits. Medial pterygoid muscles did not compensate. Condylar bone density was reduced. CONCLUSION: Bilateral treatment of the rabbit masseter by BoNT severely affected chewing performance. Even after a 3-month recovery period, deficits remained in bite force, muscle size and condylar bone density.

Medication Abortion and Abortion Pill Reversal: An Exploratory Analysis on the Influence of Others in Women's Decision-Making.

Introduction As medication abortion accounts for a growing share of abortions in the United States, an increasing number of women are seeking abortion pill reversal (APR). These decisions are typically not made in isolation. However, little research exists on women's APR decision-making and the role played by people close to them. Methods We surveyed women who contacted a national hotline for information on APR and who completed a two-week treatment protocol with progesterone (n = 67). We analyzed women's open-ended answers using thematic analysis to identify memorable messages about medication abortion and APR. Participants' communication with other people in their lives was assessed using the Isolation subscale of the Individual Level Abortion Stigma (ILAS) scale, and decision-making difficulty was assessed using a Likert scale. Results Thirty-six respondents met the eligibility criteria and filled out the ILAS and decision-difficulty scales. Women tended to talk with family and friends about their medication abortion decisions, while they typically sought information online when deciding about APR. Women reported greater stigma in their disclosures about their abortions than in their disclosures about APR (p = 0.006). Conclusion Memorable messages influence women's decisions to pursue medication abortion and APR.

Cranial suture morphometry and mechanical response to loading: 2D vs. 3D assumptions and characterization.

Cranial sutures are complex soft tissue structures whose mechanics are often studied due to their link with bone growth in the skull. Researchers will often use a cross-sectional two-dimensional slice to define suture geometry when studying morphometry and/or mechanical response to loading. However, using a single cross section neglects the full suture complexity and may introduce significant errors when defining their form. This study aims to determine trends in suture path variability through skull thickness in a swine model and the implications of using a 'representative' cross section on mechanical modeling. To explore these questions, a mixture of quantitative analysis of computed tomography images and finite element models was used. The linear interdigitation and width of coronal and sagittal sutures were analyzed on offset transverse planes through the skull thickness. It was found that sagittal suture width and interdigitation were largely consistent through the skull thickness, whereas the coronal suture showed significant variation in both. The finite element study found that average values of displacement and strain were similar between the two-dimensionally variable and three-dimensionally variable models. Larger ranges and more complex distributions of strain were found in the three-dimensionally variable model. Outcomes of this study indicate that the appropriateness of using a representative cross section to describe suture morphometry and predict mechanical response should depend on specific research questions and goals. Two-dimensional approximations can be sufficient for less-interdigitated sutures and when bulk site mechanics are of interest, while taking the true three-dimensional geometry into account is necessary when considering spatial variability and local mechanical response.

Repeated botulinum treatment of rabbit masseter causes cumulative tissue damage.

OBJECTIVE: Botulinum neurotoxins (BoNT) are used in masticatory muscles for pain relief, unloading of the mandible, and cosmetic facial contouring. Treatment is often repeated every few months as function returns. This study assessed masticatory function and musculoskeletal structure after multiple BoNT treatment of the rabbit masseter. DESIGN: Female rabbits received 3 injections of BoNT (n = 13) or saline (n = 5) into one masseter muscle at intervals of 12 weeks. The contralateral side served as control. Periodic measurements of masticatory electromyography (EMG) and stimulated anterior bite force were made. After the final 12-week recovery interval, neuromuscular connection was investigated by stimulating the masseteric nerve to elicit an evoked EMG response. Mandibular specimens were collected for microCT analysis, and masseters were collected for histomorphometry and counts of replicating cells. RESULTS: Control and saline-injected muscles maintained consistent masticatory EMG and anterior bite force throughout the study. BoNT-injected masseters showed strong declines after each injection; during the 12-week recovery period, masticatory EMG and anterior bite force improved, although only electrical activity reached normal levels. Multiple injection resulted in persistently atrophied muscle fibers with fibrosis, and notable loss of bone from the mandibular body and condyle. The uninjected masseters of the BoNT group also showed evidence of mild toxin-related changes. CONCLUSIONS: Although muscle function is mostly regained after each injection, masseters receiving multiple doses of BoNT show extensive damage. In addition, mandibular bone density is decreased on the injected side.

Botulinum toxin in the masseter muscle: Lingering effects of denervation.

Botulinum neurotoxins (BoNTs) are paralytic agents used to treat a variety of conditions in jaw muscles. Although their effect is considered temporary, there are reports of persistent functional changes. Using rabbits that received BoNT injection in one masseter muscle, the recovery of neuromuscular connection was investigated using nerve stimulation to evoke an electromyographic (EMG) response, and the recovery of muscle fibers was investigated using histological morphometry and bromodeoxyuridine (BrdU) immunohistochemistry. One month after treatment, evoked EMG was greatly reduced in both amplitude and duration, indicating that little reinnervation had taken place. Muscle fibers were atrophied and collagenous tissue was increased. Three months after treatment, evoked EMG duration was normal, indicating that at least some neuromuscular junctions were functional. Histologically, some muscle fibers were hypertrophied, some were still atrophied, and some appeared to have died. Fibrosis was still apparent amid slight increases in dividing cells and regenerating fibers. The histological effects of BoNT were evident although attenuated at a distance of about 1 cm from the injection level, but no regional differences could be discerned for the evoked EMGs. In conclusion, there were persistent muscular deficits seen 3 months after BoNT treatment that may have been caused by the failure of some affected muscle fibers to become reinnervated.

Mothers' Support Preferences With Their Chronically Ill Child's Health Care Team.

Children living with medical complexities are a growing population in the United States. Supportive pediatric health care team members are arguably the single most important factor in helping mothers manage their child's multifaceted condition. To better understand what constitutes helpful support from health care team members, we interviewed 17 mothers affiliated with a pediatric palliative care program at a large Midwestern U.S. hospital. Using Charmaz's approach to grounded theory analysis, we found that mothers desired a collaborative partnership with their child's health care team. However, the development of this partnership was contingent upon team members' effective use of informational, emotional, and network support. We identified two specific strategies that qualified each of these three different types of helpful supportive communication. These strategies may be implemented into training and educational programs for health care professionals to improve their communication skills.

#AbortionChangesYou: A Case Study to Understand the Communicative Tensions in Women's Medication Abortion Narratives.

One out of four women in the United States will have an abortion by age 45. While abortion rates are steadily declining in the United States, the rate of medication abortions continues to increase, with 39% of all abortions being medication abortions. Our study is one of the first to analyze women's narratives after having had a medication abortion. Using relational dialectics theory, we conducted a case study of the nonpartisan website, Abortion Changes You. Our contrapuntal analysis rendered four sites of dialectical tension found across women's blog posts: only choice vs. other alternatives, unprepared vs. knowledgeable, relief vs. regret, and silence vs. openness. Each site of struggle characterized a different noteworthy moment within a woman's medication abortion experience: the decision, the medication abortion process, identity after abortion, and managing the stigmatizing silence before and after the abortion. We discuss theoretical and practical implications about how the larger politicized discourses prevalent within the abortion debate impact the liminality of women who are contemplating a medication abortion and affect their own narrative construction about the medication abortion experience.

When Facing Hopeful and Hopeless Experiences: Using Snyder's Hope Theory to Understand Parents' Caregiving Experiences for Their Medically Complex Child.

INTRODUCTION: An emerging subpopulation within pediatric chronic illness is children living with complex chronic conditions. Managing a child's complex chronic conditions can be emotionally taxing for parents. Many parents regard hope as a "life-sustaining and essential" process for them. METHOD: We used the central concepts within Snyder's hope theory to guide our directed content analysis of parents' interviews about their hopeful and hopeless experiences. Our sample consisted of primarily Christian married mothers. RESULTS: We found themes within each concept of Snyder's hope theory that clarifies the social and communicative processes that facilitate more hopeful thinking for parents. DISCUSSION: Understanding how individuals communicate or enact hopeful thinking is an important contributor to performing hope in social settings like hospitals and nonprofit organizations (Ronald McDonald House) that support parents with medically complex children. Our findings indicate that messages should help parents identify care solutions, offer words of encouragement, and help parents create life goals that maintain a child's quality of life.

"You Are Not Alone": Advice Giving for Parents of Children Living with Complex Chronic Conditions.

Parental advice giving serves as an important form of informational support for parents of children living with complex chronic conditions (CCCs). These messages can provide backchannel insights into social challenges, best practices, and may offer different forms of experiential wisdom garnered from their own parental caregiving experiences. Contributing to the naturalistic, health-context investigations of advice messages, we interviewed 35 parents who discussed their experiences with parenting their medically complex child. Part of the broader interview protocol asked parents about advice they would offer to other parents like them. We conducted a thematic analysis of parents' responses to these questions to understand advice content, form of advice giving messages, challenges experienced by parents, and suggested best practices for managing a child's CCC. We present our findings and discuss implications on educating health care professionals about how to cultivate advice networks and the need for more parent peer mentoring programs.

Mechanobiology of bone and suture - Results from a pig model.

OBJECTIVE: To compare the morphology and mechanical function of sutures in normal pigs and minipigs to those of Yucatan minipigs, a natural model for midfacial hypoplasia. SETTING AND SAMPLE POPULATION: Research took place at the Department of Orthodontics at the University of Washington and used varying sample sizes of normal-snouted pigs and Yucatan minipigs. MATERIAL AND METHODS: Skulls and heads were examined for morphology of the nasofrontal suture using computed tomography and histology. Strain gauge recordings were made of sutural strain during mastication and during cyclic tensile loading of the nasofrontal suture. RESULTS: Sutures in Yucatans had narrower gaps than same-age normal pigs. The nasofrontal suture was simpler in construction and had more active osteoblasts on the bone fronts in Yucatans. The sutural ligament was less well organized, and based on a small sample, masticatory strain appeared to be lower than in normal minipigs. However, sutures were not fused and showed similar strains in response to the cyclic loading procedure. CONCLUSION: Midfacial hypoplasia in Yucatan pigs has the likely proximate cause of hyperossification. Yet prior to fusion, the sutures appear to be amenable to treatment that would promote their growth rate.

"I Will Communicate With You, But Let Me Be In Control": Understanding How Parents Manage Private Information About Their Chronically Ill Children.

Parents have a significant role in the management of a child's chronic condition. Parents are often the only consistent individuals managing a child's health across his or her childhood and adolescence (e.g., present for all appointments and medical procedures). Many of the responsibilities required of parents involve communication work, where parents must strategically and actively design messages as they interact with medical professionals, other family, and friends. Using communication privacy management theory, we analyzed interviews conducted with 35 parents to understand the motivations and strategies involved in their regulation of information about their child's chronic condition. These findings have important practical implications because parental involvement in a chronically ill child's care has direct effects on familial adaptation and adjustment.

Cyclic loading effects on craniofacial strain and sutural growth in pigs.

INTRODUCTION: Current craniofacial growth modification devices use static forces, but cyclic forces are believed by some to be more effective. The latter have not been evaluated in large animal models, and it is not known how such forces are transmitted to distant parts of the skull. In this study, we aimed to (1) develop a portable loading system capable of delivering reliable cyclic loads to the porcine nasofrontal suture (NFS), (2) explore strain transmission to distant sutures, and (3) characterize the sutural growth effects in a small pilot study. METHODS: After we validated the device, cyclic (2.5 Hz) tensile loads were applied unilaterally to the NFS of 6 abattoir pig heads, with strain gauges on multiple sutures. Similar loading was applied to 3-month-old live pigs (Sus scrofa, n = 4 and 1 sham) 30 minutes per day for 5 days. These animals received fluorescent markers of mineralization on loading days 1 and 3. Suture strains were recorded on day 5. Histomorphometric analysis quantified suture width and mineral apposition rate. RESULTS: A wearable loading system was developed to produce an average of +900 microstrain at the targeted NFS. Substantial strains were seen at the contralateral NFS and midline sutures, but bone strains were low. Strain patterns were similar ex vivo and in vivo, with the latter generally having higher magnitudes. Preliminary evidence demonstrates wider sutures with higher mineral apposition rates in the loaded sutures. CONCLUSIONS: Daily spurts of cyclic load caused sutural strain throughout the skull. This regimen most likely enhances sutural growth and may be therapeutically useful.

"You Know the Medicine, I Know My Kid": How Parents Advocate for Their Children Living With Complex Chronic Conditions.

Caring for a child with a chronic condition has received considerable attention in the pediatric health literature. Today, approximately 1 out of 5 North American children are diagnosed with a chronic condition that requires parents to become caregivers and advocates. Although advocacy is regarded as a significant aspect to parental caregiving, more research is needed to better define this oversimplified and misrepresented concept in clinical practice and research. Subsequently, we interviewed 35 parents of children diagnosed with complex chronic conditions. Within our analysis, we identified three themes that elaborate upon how parental advocacy is socially constructed through communication behaviors and partnerships with other people (e.g., medical professionals, family, school educators). We also discuss the emotional side of advocacy, and proffer suggestions to practitioners who work with parents to form collaborative care teams.

The locomotion of Babakotia radofilai inferred from epiphyseal and diaphyseal morphology of the humerus and femur.

Palaeopropithecids, or "sloth lemurs," are a diverse clade of large-bodied Malagasy subfossil primates characterized by their inferred suspensory positional behavior. The most recently discovered genus of the palaeopropithecids is Babakotia, and it has been described as more arboreal than Mesopropithecus, but less than Palaeopropithecus. In this article, the within-bone and between-bones articular and cross-sectional diaphyseal proportions of the humerus and femur of Babakotia were compared to extant lemurs, Mesopropithecus and Palaeopropithecus in order to further understand its arboreal adaptations. Additionally, a sample of apes and sloths (Choloepus and Bradypus) are included as functional outgroups composed of suspensory adapted primates and non-primates. Results show that Babakotia and Mesopropithecus both have high humeral/femoral shaft strength proportions, similar to extant great apes and sloths and indicative of forelimb suspensory behavior, with Babakotia more extreme in this regard. All three subfossil taxa have relatively large femoral heads, also associated with suspension in modern taxa. However, Babakotia and Mesopropithecus (but not Palaeopropithecus) have relatively small femoral head surface area to shaft strength proportions suggesting that hind-limb positioning in these taxa during climbing and other behaviors was different than in extant great apes, involving less mobility. Knee and humeral articular dimensions relative to shaft strengths are small in Babakotia and Mesopropithecus, similar to those found in modern sloths and divergent from those in extant great apes and lemurs, suggesting more sloth-like use of these joints during locomotion. Mesopropithecus and Babakotia are more similar to Choloepus in humerofemoral head and length proportions while Palaeopropithecus is more similar to Bradypus. These results provide further evidence of the suspensory adaptations of Babakotia and further highlight similarities to both extant suspensory primates and non-primate slow arboreal climbers and hangers. J. Morphol. 277:1199-1218, 2016. © 2016 Wiley Periodicals, Inc.

Intracranial pressure changes during mouse development.

During early stages of postnatal development, pressure from the growing brain as well as cerebrospinal fluid, i.e. intracranial pressure (ICP), load the calvarial bones. It is likely that such loading contributes to the peripheral bone formation at the sutural edges of calvarial bones, especially shortly after birth when the brain is growing rapidly. The aim of this study was to quantify ICP during mouse development. A custom pressure monitoring system was developed and calibrated. It was then used to measure ICP in a total of seventy three wild type mice at postnatal (P) day 3, 10, 20, 31 and 70. Retrospectively, the sample in each age group with the closest ICP to the average value was scanned using micro-computed tomography to estimate cranial growth. ICP increased from 1.33±0.87mmHg at P3 to 1.92±0.78mmHg at P10 and 3.60±1.08mmHg at P20. In older animals, ICP plateaued at about 4mmHg. There were statistically significant differences between the ICP at the P3 vs. P20, and P10 vs. P20. In the samples that were scanned, intracranial volume and skull length followed a similar pattern of increase up to P20 and then plateaued at older ages. These data are consistent with the possibility of ICP being a contributing factor to bone formation at the sutures during early stages of development. The data can be further used for development and validation of computational models of skull growth.