Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study.

AIM: Amnion and chorion membranes possess unique inherited biological properties that enhance wound healing and may accelerate periodontal regeneration. The present study aims to evaluate and compare the efficacy of amnion and chorion membranes in the treatment of furcation defects. MATERIALS AND METHODS: A total of 20 patients were selected and were randomly allocated to group I and group II with 10 subjects in each group. Amnion and chorion membranes are placental-derived membranes that accelerate regeneration by having natural growth factors with their antimicrobial and inflammation reduction properties. Group I was treated using bone grafting with decalcified freeze-dried bone allograft (DFDBA) and placement of amnion as a membrane for guided tissue regeneration (GTR) whereas group II was treated using bone grafting with DFDBA and placement of chorion as a membrane for GTR. The patients were followed for clinical and radiographic parameters and were evaluated between 3 and 6 months after surgery. RESULT: In intragroup comparison, a significant difference was evident in both the groups for all the clinical and radiographic parameters within the groups. (p = 0.01) This means both amnion and chorion membranes showed statistically significant regenerative efficacy. In intergroup comparison, the results show that all the clinical parameters and radiographic parameters show no significant difference between the groups. CONCLUSION: The amnion and chorion membranes had similar regenerative efficacy in combination with DFDBA in patients with buccal degree II furcation defects in mandibular molars. CLINICAL SIGNIFICANCE: The amnion and chorion membranes have shown significant improvement in clinical and radiographic parameters when used for the treatment of buccal degree II furcation defects in mandibular molars. How to cite this article: Mallapragda S, Gupta R, Gupta S, et al. Evaluation of Regenerative Efficacy of Amnion and Chorion Membrane in Treatment of Mandibular Molar Furcation Defects: A Clinico-radiographic Study. J Contemp Dent Pract 2024;25(2):160-167.

US Evaluation of Twin Pregnancies: Importance of Chorionicity and Amnionicity.

The twin birth rate is increasing in the United States. Twin pregnancies can be dichorionic or monochorionic (MC). MC twins account for 20% of twin pregnancies but 30% of all-cause pregnancy-related complications. This article describes the imaging findings that establish chorionicity and amnionicity. Ideally, these are established in the first trimester when accuracy is high, but they can also be determined later in pregnancy. Complications unique to MC twin pregnancy include twin-twin transfusion syndrome, twin anemia polycythemia sequence, twin reversed arterial perfusion sequence, and selective fetal growth restriction. The US features, staging systems, and management of these complications are reviewed, and the consequences of MC twin demise are illustrated. Ongoing surveillance for these conditions starts at 16 weeks gestation. Monoamniotic (MA) twins are a small subset of MC twins. In addition to all of the MC complications, specific MA complications include cord entanglement and conjoined twinning. Radiologists must be able to determine chorionicity and amnionicity and should be aware of potential complications so that patients may be referred to appropriate regional specialized centers. A proposed algorithm for referral to specialized fetal treatment centers is outlined. Online supplemental material is available for this article. ©RSNA, 2019.

Isolated Ascites in a Monochorionic Twin after Fetoscopic Laser Ablation Is Not Necessarily Secondary to Recurrence or Anaemia: Bowel Complications in Twin-to-Twin Transfusion Syndrome after Fetoscopic Laser Ablation.

BACKGROUND/PURPOSE: We report a case study of jejunal atresia and the results of a systematic literature review of all reported cases of bowel complications occurring after fetoscopic laser ablation (FLA) for the treatment of twin-to-twin transfusion syndrome (TTTS). METHODS: A systematic literature review was performed of bowel complications after FLA for TTTS according to PRISMA guidelines. RESULTS: There are 11 published cases of small bowel atresia, 5 cases of necrotising enterocolitis (NEC), and 2 cases with foetal bowel perforations. Recipient twins were more likely to be affected by small bowel atresia (7 recipient and 4 donor cases) and NEC (3 recipient and 2 donor twins). Prenatal ultrasonographic abnormalities were demonstrated in 7 out of 9 cases with bowel atresia and in both cases of bowel perforation. The overall survival rate for neonates with bowel complications after FLA is 72%, but is much lower for co-twins at 22%. The survival rates for jejunoileal atresia and NEC are 91 and 40%, respectively. CONCLUSIONS: It is uncertain as to whether these bowel anomalies are due to bowel ischaemia associated with TTTS, the treatment with FLA, or a combination of both. Cases with prenatal abdominal ultrasonographic abnormalities after FLA should have close prenatal and postnatal assessment to detect bowel complications.

Preterm premature rupture of membranes is a collateral effect of improvement in perinatal outcomes following fetoscopic coagulation of chorionic vessels for twin-twin transfusion syndrome: a retrospective observational study of 1092 cases.

OBJECTIVES: Preterm premature rupture of membranes (PPROM) is a leading complication following fetoscopic laser coagulation (FLC) for twin-twin transfusion syndrome (TTTS). Our primary objective was to describe the impact of improvements in surgical technique on survival and rate of PPROM over time. The secondary objective was to assess potential risk factors for PPROM. DESIGN AND SETTING: Single-centre retrospective observational study. POPULATION: 1092 consecutive cases of TTTS operated by FLC between 2000 and 2016, with a 6.8% rate of loss to follow up. METHODS: The incidence of PPROM and potential risk factors were analysed using competing risks models. MAIN OUTCOME MEASURES: PPROM, neonatal survival and neurological damage at 28 days. RESULTS: PPROM <32 weeks increased from 15 to 40% between 2000 and 2016 along with an overall improvement of perinatal outcomes: dual survival rose from 42 to 66% whereas dual losses dropped two-fold, from 19 to 9%. Gestational age at surgery at <17 weeks was a significant risk-factor for PPROM, with an additional risk of 10% within the first week of surgery. Although early PPROM at <20 weeks carried a 56% risk of miscarriage, the occurrence of PPROM at >20 weeks did not affect survival, despite an increase in preterm birth at <32 weeks. CONCLUSIONS: With significant improvement in perinatal outcomes, possibly related to improvements in surgical technique, postoperative complications have shifted to non-lethal obstetric complications such as PPROM, with rather reassuring postnatal outcomes, despite an increase in preterm birth and, potentially, morbidity. Early surgeries (<17 weeks) are at higher risk of postoperative PPROM. TWEETABLE ABSTRACT: Following laser/TTTS, rates of PPROM increased with perinatal survival; surgeries at <17 weeks are at highest risk.

Endoscopic laser dichorionization of the placenta in the treatment of severe twin-twin transfusion syndrome.

OBJECTIVES: To describe the results of a technique of laser ablation of placental vessels in the treatment of severe twin-twin transfusion syndrome (TTTS), which is characterized by separation of the fetoplacental vascular territories and dichorionization of the placenta. PATIENTS AND METHODS: Descriptive analysis of TTTS cases treated with the endoscopic laser dichorionization of the placenta (ELDP) procedure. The variables evaluated were the occurrence of reversal of the donor-recipient phenotype, persistence of TTTS or twin anemia-polycythemia sequence (TAPS); gestational age at delivery; discharge from the hospital of at least 1 or 2 live neonates, and incidence of neurological alterations among survivors. RESULTS: 67 patients were treated with the ELDP procedure. There was no persistence of TTTS, reversal of the donor-recipient phenotype or TAPS. The median gestational age at delivery was 33.0 (23.6-37.7) weeks. The rate of discharge from the hospital of at least 1 or 2 live neonates was 88.2% (67/76) and 71.1% (54/76), respectively. Among survivors, 17 (17/121 = 14.0%) children presented with neurodevelopmental alterations during clinical follow-up. CONCLUSIONS: The major contribution of this study was the demonstration that the ELDP technique appears to be associated with a low risk of persistence or recurrence of TTTS and TAPS.

Chorioamnion plugging and the risk of preterm premature rupture of membranes after laser surgery in twin-twin transfusion syndrome.

OBJECTIVE: To examine the incidence of preterm premature rupture of membranes (PPROM) in pregnancies affected by twin-twin transfusion syndrome (TTTS) treated with laser photocoagulation where an absorbable gelatin sponge was used as a chorioamnion sealant of the fetoscopic access port. METHOD: A retrospective review was undertaken of consecutive cases undergoing fetoscopic directed laser surgery for TTTS between October 2006 and November 2008 at Texas Children's Fetal Center, in which an absorbable gelatin sponge, used as a chorioamnion 'plug', was placed at the conclusion of the intervention as a possible prophylactic measure to prevent PPROM. We excluded cases that had a failure of plug placement and those in which it was not attempted. PPROM was defined as rupture of membranes before 34 weeks' gestation. A comparison was performed between the PPROM group and a no-PPROM group to determine risk factors and outcomes. RESULTS: Successful plug placement occurred in 79 of 84 cases (94%) in which it was attempted after laser surgery, with a rate of PPROM of 34% in these patients. PPROM occurred at an average gestational age of 26.5 +/- 3.6 weeks, with an average procedure-to-PPROM interval of 5.2 +/- 3.5 weeks. There were no statistically significant differences between the PPROM group and the no-PPROM group in maternal demographics or preoperative parameters including: amniotic fluid volumes in the recipient twin's gestational sac, volume of amnioreduction, and location of the placenta. The procedure-to-delivery interval for the total cohort (n = 79) was 9.2 +/- 4.7 weeks, without a significant difference between the two groups (P = 0.08). However, after exclusion of one PPROM outlier, the PPROM group had an average procedure-to-delivery time 2 weeks shorter than the group with no PPROM (P = 0.03). The live birth rates were similar in the PPROM and no-PPROM groups, at 77 and 73%, respectively. However, the average recipient's weight in the PPROM group was significantly lower than in the no-PPROM group (1321 +/- 493 vs. 1705 +/- 576 g; P = 0.02). CONCLUSION: The rate of PPROM and the mean gestational age at delivery in pregnancies in which an absorbable gelatin sponge was used as a sealant of the fetoscopic port following laser photocoagulation for TTTS were comparable to those that have been reported by other laser centers where membrane sealants were not used. A randomized controlled trial should be considered to evaluate the effect of chorioamnion plugging.

A definition of selectivity in laser coagulation of chorionic plate anastomoses in twin-to-twin transfusion syndrome and its relationship to perinatal outcome.

OBJECTIVE: This study was undertaken to correlate selectivity of surgery and perinatal outcome in twin-to-twin transfusion syndrome treated by endoscopic laser coagulation, using a quantitative definition of selectivity. STUDY DESIGN: 287 consecutive cases of severe twin-to-twin transfusion syndrome were reviewed. A selectivity index was built as the ratio of selective over nonselective coagulations per procedure. Outcome measures were survival at 28 days and failure of surgery as defined by recurrence of twin-to-twin transfusion syndrome or fetofetal hemorrhage. RESULTS: Two populations were identified: a high selectivity group (63.8%) and a low selectivity group (36.2%). Survival of at least one twin and survival of both twins were higher in the high-selectivity group (p = .007 and p = .04 respectively). Failure of surgery rates were similar in both groups. CONCLUSION: A quantitative definition of selectivity appears justified by the large variations found in the practice of a single center and by significant differences in outcome. Survival is significantly improved in highly selective procedures.

Transient chorioamniotic membrane separation after fetoscope guide laser therapy for twin-twin transfusion syndrome: a case report.

Chorioamniotic membrane separation (CMS) means that the close attachment of amniotic and chorionic membranes is disrupted, usually following the traumatic entry into the amniotic cavity including fetal therapy. We report a case of twin-twin transfusion syndrome receiving fetoscopic guide laser therapy at gestational age of 19 weeks with partial CMS detected at the fifth week (gestational age of 24 weeks) after surgery and resealed 1 week later. There was no more CMS noted till delivery at gestational age of 34 weeks 6 days. CMS after fetoscope surgery may reseal spontaneously.

Hypothetical role of prostaglandins in the onset of preterm labor after fetal surgery.

Preterm labor is one of the most important factors limiting the advancement of fetal surgery programs. While prostaglandins (PGs) have long been indicated as the key factor in the initiation of labor in humans, there is significant evidence showing that the chorionic membrane acts as a powerful barrier between the decidua/myometrium and amniotic PGs during normal pregnancy. After either open or endoscopic fetal surgery the imperfect, non-hermetical closure of the chorion permits leakage of PGs from the amnionic sac, allowing them to reach the decidua and myometrium. The surgical wound in the chorionic barrier could be the major factor involved in preterm labor and delivery after human fetal surgery.

Intertwin anastomoses in monochorionic placentas after fetoscopic laser coagulation for twin-to-twin transfusion syndrome: is there more than meets the eye?

OBJECTIVE: This study was undertaken to detect missed anastomoses on the chorionic surface as well as hidden connections in the depth of the cotyledons in placentas after laser coagulation for twin-to-twin transfusion syndrome (TTTS) and to correlate these findings to clinical outcome. STUDY DESIGN: All cord vessels were injected with dyed barium sulphate. A digital photograph of the chorionic surface angioarchitecture and single-shot digital X-ray (Rx) angiograms were made. The presence and diameter of any missed anastomoses on the chorionic surface and of any hidden angiographic connections were determined. RESULTS: Fifty placentas were analyzed, 7 of double intrauterine fetal death (IUFD) and 43 of double survivors. In 9 of 43 (21%) cases with double survival and in all 7 cases of double IUFD, missed anastomoses were identified that should have been ablated by laser coagulation (P < .001). There appeared to be a correlation between the type and diameter of missed anastomoses on the chorionic surface and the clinical outcome. Placentas with missed large arteriovenous/venoarterial anastomoses (AV/VA) (N = 8) were from cases with recurrent TTTS or double IUFD (unless compensated by a large arterioarterial anastomosis [AA]). Next, missed small AV/VA (N = 4) without AA resulted in isolated (ie, without TTTS) discordant hemoglobin levels requiring intrauterine transfusion. Finally, when there were no missed anastomoses (N = 34), TTTS had resolved in all cases and outcome was good, although 1 case had discordant hemoglobin values treated with a single intrauterine transfusion and 4 others had discordant hemoglobin at birth. On Rx angiography, potential hidden connections were present, all but 1 case. CONCLUSION: Coagulation of all anastomoses visible on the chorionic surface seems adequate to treat TTTS. However, hidden connections in the depth of the cotyledon could not be excluded and may be involved in lesser degrees of intertwin transfusion.

Incidence and impact of perioperative complications in 175 fetoscopy-guided laser coagulations of chorionic plate anastomoses in fetofetal transfusion syndrome before 26 weeks of gestation.

OBJECTIVE: The purpose of this study was to evaluate the perioperative complications in fetoscopy-guided laser therapy in fetofetal transfusion syndrome. STUDY DESIGN: Details of fetofetal transfusion syndrome cases who were delivered between 1999 and 2004 in a single center were reviewed retrospectively. RESULTS: One hundred seventy-five procedures were performed percutaneously with the use of local anesthesia. Survival at 6 months of at least 1, 1, and 2 babies was 73%, 38%, and 35%, respectively. Placental abruption and miscarriage was diagnosed in 3 and 12 cases, respectively. Premature rupture of membranes occurred in 49 cases (28%) and including 12, 29, and 46 cases that occurred before 24, 28, and 34 weeks of gestation, respectively. The entry of the trocar was transplacental in 48 cases (27%), but it was not associated with miscarriage (P = .26), premature rupture of membranes (P = .58), or placental abruption (P = .37). CONCLUSION: Fetoscopic laser treatment of fetofetal transfusion syndrome can be performed percutaneously with local anesthesia without significant maternal morbidity. Transplacental entry was not associated with premature rupture of membranes or miscarriage.

The chick chorioallantoic membrane as a model tissue for surgical retinal research and simulation.

PURPOSE: We describe the use of chick chorioallantoic membrane (CAM) as a model system for the study of the precision and safety of vitreoretinal microsurgical instruments and techniques. METHODS: The CAM was prepared for experimentation with and without its inner shell membrane (ISM) attached for in vivo and in vitro experiments that simulated medical and surgical interventions on the retina. RESULTS: The CAM's ease of use, low cost, and anatomic structure make it a convenient model for surgical retinal and retinal vascular modeling. CONCLUSION: While CAM has been used extensively in the past for ocular angiogenesis studies, we describe the tissue as a useful tool for a variety of other applications, including (1) testing of novel surgical tools and techniques for cutting and coagulating retina and its vasculature, (2) testing vessel cannulation and injection techniques, (3) angiographic studies, and (4) endoscopic surgery.

Tissue integrity is essential for ectopic implantation of human endometrium in the chicken chorioallantoic membrane.

BACKGROUND: Not all women with patent tubes develop clinically manifest endometriosis. Quality and quantity of endometrium in retrograde menstruation may be the determining factor in the development of the disease. We hypothesize that retrograde shedding of endometrial fragments with preserved integrity facilitates implantation of endometrium in ectopic locations, resulting in endometriotic lesion development. We evaluate the impact of tissue integrity on the success of endometriosis-like lesion development in the chicken embryo chorioallantoic membrane (CAM) model. METHODS: Menstrual and non-menstrual (cyclic) endometrium were collected by biopsy, and either minced or enzymatically dispersed. Spontaneously shed menstrual effluent was collected by a menstrual cup, and cells and tissue were isolated. We evaluated whether infiltration or lesion formation in the CAM occurred after transplantation of endometrium onto the CAM. RESULTS: Transplantation of biopsied menstrual and cyclic endometrium fragments, and of endometrium fragments >1 mm(3) isolated from menstrual effluent, resulted in lesion formation. Transplantation of endometrial cells isolated from menstrual effluent did not lead to lesion formation. After transplantation of digested biopsied cyclic endometrium, infiltration in the CAM but no lesions were observed. CONCLUSION: In the CAM assay, integrity of tissue architecture determines success of implantation of human endometrium in ectopic locations.

Effect of irradiation on vascularization of corneas grafted onto chorioallantoic membranes.

Several studies have shown that total body irradiation decreases the angiogenic response to corneal cauterization. This inhibition could be due to alterations in angiogenic stimuli within injured corneas and/or to a decreased ability of irradiated animals to respond to such stimuli. To determine whether total body irradiation specifically affects angiogenic stimuli within injured corneal tissue, cauterized corneas from mice exposed to 900 rads of total body irradiation and from non-irradiated controls were grafted onto the chorioallantoic membranes (CAM) of chick embryos and their abilities to stimulate the ingrowth of healthy embryonic blood vessels were compared. Cauterized corneas incorporated into CAM mesenchymal tissue were invaded by blood vessels in 34.6% of the irradiated group and in 75% of the non-irradiated controls. This difference in the two groups was statistically significant (P less than 0.03). Total body irradiation significantly decreased the frequency of vascular invasion of cauterized corneal tissues by healthy CAM blood vessels. This finding suggests that total body irradiation can specifically affect the stimulus for angiogenesis within cauterized corneas.

Attempts surgically to induce chorionic fusion between embryos.

Intercornual fistulas were made in the uteri of 19 ewes in an attempt to induce chorionic fusion between fetuses. Ewes were 28 to 40 days pregnant with at least one fetus per horn. Sections were removed from the dorsomedial wall of each uterine horn, and left and right horns were sutured together around the openings to produce the fistulas. In some cases a doughnut-shaped sheet of silastic was inserted between the horns, and in most cases the chorioallantoic membranes of the respective fetuses were sutured to one another prior to suturing the uterine walls. In the 16 animals in which intercornual fistulas were constructed in the area of the intercornual ligament, no chorionic anastomosis was induced. In one of the three animals in which fistulas were produced distal to that ligament, the fistula remained patent 25 days post-surgery, and membranes of two female fetuses were joined, through the opening, by a narrow strand of chorionic tissue. We concluded that this technique was not a promising one for induction of choriovascular anastomosis.

Immunocytological study on the differentiation of chick and quail adenohypophysis epithelial rudiments, grafted or cultivated in vitro: evidence for polypeptidic hormones.

Epithelial rudiments of adenohypohysis were removed from chick and quail embryos between days 3 and 5 of development. Chick rudiments were grafted for 11--13 days onto the chorioallantoic membrane of decapitated chick embryo hosts. Quail rudiments were cultivated in vitro for 6 days. Both grafted and cultivated Rathke's pouches differentiated into adenohypophyseal tissue. The adenohypophyseal tissue cultured on chorio-allantoic membrane exhibited cells reacting with the following immune sera: anti-beta-(1--24)ACTH, anti-alpha-(17--39)-ACTH, anti-alpha-endorphin, anti-beta-endorphin and anti-beta-LPH, which also gave a positive reaction when applied to adenohypophysis of corresponding age which had differentiated in situ. In situ, corticotrophs were located exclusively in the cephalic lobe of adenohypophysis. Therefore, the differentiation of corticotrophs in the whole graft, i.e., from both cephalic and caudal lobes of Rathke's pouch, showed that the cells of the caudal lobe, or at least some of them, were uncommitted when the rudiment was removed. In vitro, tissue derived from Rathke's pouch contained cells reacting with antibodies to beta-(1--24)-ACTH, alpha-(17--39)-ACTH, and beta-LPH, as did adenohypophysis from quail embryos of corresponding age (9--10 days), differentiated in situ. The differentiation of quail Rathke's pouch in vitro corroborates that differentiation can occur without influence from hypothalamus and, moreover, shows that at least some kinds of cells can differentiate without influence exerted by any other encephalic factors, and in the absence of mesenchyme. The question arises whether fibroblastic cells derived from Rathke's pouch cells act as feeder-cells and/or secrete some factors promoting differentiation.