Incisor Eruption Research Articles

A comparison of skeletal and dental changes in patients with a Class II relationship treated with clear aligner mandibular advancement and Herbst appliance followed by comprehensive orthodontic treatment

The objective of this study was to compare the skeletal and dental changes of patients with a Class II relationship treated with clear aligner mandibular advancement (MA) and Herbst appliances followed by comprehensive orthodontic treatment. The participants included 20 patients treated with MA and 20 with the Herbst appliance. Orthodontic records were taken before treatment, after the functional appliance, and completion of phase II treatment. The skeletal and dental changes across the 3-time periods were evaluated using a matched paired t test for each treatment. A 2-sample t test was used to examine the changes across periods between 2 treatment groups (P<0.05). Significant reduction in overjet, overbite, and change in molar relationship were obtained by both appliances with similar skeletal and dental contributions. This was contributed by a forward movement of the mandible and mandibular molars, backward movement of the maxillary molars, and retraction of the maxillary incisors. After phase II treatment, both appliances could maintain the skeletal and dental changes achieved during the advancement phase. Greater change in overbite (2.4 mm vs 1.4 mm), an eruption of maxillary incisors (0.9 mm vs 0.1 mm), and proclination of mandibular incisors were found with the Herbst group (3.9° vs -2.1°). The average total treatment time was similar with the 2 appliances. Both functional appliances were equally effective in reducing the overjet and overbite and achieving a Class I molar relationship with a similar length of treatment time. The Herbst design lacked control of the mandibular incisor proclination, and clear aligners offered better vertical control and management of the mandibular incisor inclination.

A MULTIPLE TOOTH TALE: A UNIQUE CASE REPORT OF 33 ODONTOMES

Odontomas are benign asymptomatic lesions associated with delayed eruption or detected accidently on radiographic examination. This is a case report of female patient aged eight years with chief compliant of non-eruption of maxillary central incisor. On radiographic examination, multiple denticles were seen hindering path of eruption of permanent central incisor. The treatment protocol followed was surgical removal of odontoma encouraging eruption. Early recognition allows better prognosis by preventing alterations in surrounding hard and soft tissues.

Forensic age assessment of late-term bovine fetuses

BackgroundTransporting pregnant cattle that have passed 90% or more of the expected gestation period (G90 threshold) is prohibited within the European Union. Therefore, there is a need to determine whether this threshold has been exceeded in late-gestation cows sent to slaughter. The aim of this study was to evaluate fetal parameters’ reliability for use in forensic age assessment of late-term Holstein fetuses.ResultsAnalysis of the gestation length of 2734 Holsteins that calved with a single liveborn fetus revealed a median gestation length of 278 days with 99% of parturitions occurring between day 261 and 290, corresponding to G90 thresholds of 235 and 261 days, respectively. The association between gestation length and neonatal body weight had an R2 of 0.27. The influence of fetal sex and cow parity on gestation length was ± 2 days. The eruption of incisor and canine teeth was assessed in preterm calves delivered by caesarean section (n = 52) and full-term neonatal calves (n = 54). Statistical analysis of tooth eruption data showed a statistically significant variation in fetal age at tooth eruption.ConclusionsDefining the G90 threshold for a cow not having reached parturition is challenging. Body weight was not found to be a reliable parameter for identifying fetuses beyond the G90 threshold. Statistical analysis of the association between fetal age and eruption through the gingival mucosa of incisor and canine teeth revealed significant variation, making tooth eruption a challenging parameter to use in forensic cases. Assessment of the evaluated parameters, therefore, cannot be considered a scientifically validated method to conclude definitively and beyond reasonable doubt whether or not a given fetus has passed the G90 threshold.

Effect of Neonatal Factors on the Eruption of Primary Teeth in Children: A Longitudinal Prospective Cohort Study.

Eruption of first primary teeth is a normal physiological process. Antenatal nutritional deficiency and prenatal and neonatal factors play an important role in eruption of primary teeth. Neonatal factors, such as gestational age (GA), degree of prematurity, severity of neonatal illness, and birth weight are primarily related to eruption of primary teeth. The relation between neonatal factors and the timing of eruption of primary teeth has not been studied prospectively among Indian preterm infants. To evaluate the influence of neonatal factors on the eruption of primary teeth in children born preterm. A prospective longitudinal cohort study design was adopted. A total of 150 subjects were recruited by simple random sampling. Each child was followed up from birth up to 36 months. Intraoral examination was done and the teeth present in each visit were recorded. Data were statistically analyzed and interpreted. Descriptive statistics, t-tests for independent sample, and Pearson's chi-squared tests were applied. Tooth showing statistically significant difference in mean age of eruption between term and preterm categories was studied for the effect of maternal and neonatal characteristics on eruption using multivariate regression analysis. The mandibular central incisor was the first tooth to erupt. Significant determinant of eruption of mandibular incisor in term children was found to be parity, weight for GA, and complementary feeding, whereas for preterm children, significant determinants were parity, birth weight birth length, weight for GA, and complementary feeding. Neonatal factors, such as birth weight, birth length, weight for GA, and introduction of complementary feeding have a strong significant association with the eruption of primary teeth. The findings of this study will guide in the preventive management of oral health in preterm children. Indira MD, Nandlal B, Narayanappa D, et al. Effect of Neonatal Factors on the Eruption of Primary Teeth in Children: A Longitudinal Prospective Cohort Study. Int J Clin Pediatr Dent 2023;16(2):321-326.

Probiotic Therapy with Lactobacillus reuteri Rescues Social and Emotional Recognition Behavior in an Environmental Mouse Model of Autism

Introduction: Polybrominated diphenyl ethers (PBDEs) are neuroendocrine disrupting chemicals with adverse neurodevelopmental effects in children. Our group has previously shown that PBDEs produce autistic-like traits in developmentally exposed mice offspring (Kozlova et al. 2022 Arch Tox; PMID: 34687351). Our pilot data suggests that PBDEs reduce hypothalamic oxytocin expression. Moreover, PBDEs are well established disruptors of thyroid hormones. Lactobacillus reuteri (LR) is a beneficial probiotic that can increase oxytocin and thyroid hormones in other ASD mouse models. Therefore, we hypothesized that LR can restore PBDE-induced deficits in social behavior. Methods: C57BL/6N dams were dosed with a commercial mixture of PBDE congeners, DE-71, at 0.1 mg/kg/d (DE-71), or corn oil vehicle control (VEH/CON) for 10 wk (preconception: 4 wk; gestation: 3 wk; lactation: 3 wk). Dams were gavaged with L. reuteri (LR) ATCC 6475 (gift of Biogaia, Sweeden) at 10 8 CFU/mL. Cohort 1 pups (C1-LR) received LR via dam until weaning (PND 21). Cohort 2 pups (C2-LR) continued to receive gavage of LR post-weaning, daily, through 6 mo of age. Results: PCR analysis showed increased gene expression of fecal LR 6475 in feces collected from LR offspring and dams confirming efficacy of maternal LR supplementation. Compared to VEH/CON neither DE-71 nor LR disrupted normal maternal behavior. In offspring, DE-71 produced deficient short- (SRT, 30 min retention) and long-term social recognition memory (SRMT, 24 h retention) in adult females (short- and long-term) and adult males (short-term). LR normalized these deficits. The social recognition deficit was not present at PND 11 as measured on a maternal attachment homing test. On an emotional recognition test DE-71 exposed male and female offspring did not prefer investigation of stimulus mice subjected to 15 min restraint stress vs neutral conditions (normalized with LR). In a marble burying test, compared to VEH/CON, DE-71 exposed offspring showed abnormally elevated scores, which were normalized by LR treatment only in females. Developmental benchmarks that are likely affected by the TH-disruptive effects of DE-71 showed complex interactions between DE-71 and LR. LR normalized delayed (vs VEH/CON) incisor eruption in DE-71 females and improved latency of righting reflex in DE-71 males. LR normalized DE-71-induced hyperactivity on an open field test in females. Ongoing studies are focused on exploring possible mechanisms underlying the normalization provided by LR. However, our early data suggest a potential role of 1) OXT confirmed by increased plasma OXT in DE-71 male (C1-LR) mice and normalized with LR, and 2) maternal THs since LR supplementation elevated plasma T4 in DE-71 pregnant dams. Conclusions: These results suggest that maternal LR treatment during developmental PBDE exposure provides normalization of autistic-like features in a sex-dependent manner. This work is supported by a Danone North America Gut Microbiome, Yogurt and Probiotics Fellowship Grant and a University of California President's Pre-Professoriate Fellowship to E.V.K. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effect evaluation of supramolecular complex of ivermectin Aniverm-2.0% on postnatal development of rat offspring

The purpose of the research is to detect long-term effects of repeated oral administration of supramolecular complex of ivermectin Aniverm-2.0% on the postnatal development of rat offspring.Materials and methods. The studies were conducted on 16 white pregnant rats that were divided into two experimental and one control groups. The animals were kept under standard conditions of keeping and feeding. The supramolecular complex of ivermectin Aniverm-2.0% was administered to pregnant female rats (n = 6) of group 1 in the form of a suspension using an intragastric tube daily for 7 days at a dose of 15 mg/kg, and group 2 was given the substance of ivermectin (n = 5) at a dose of 8.25 mg/kg. The control female rats (n = 5) were administered 1 mL of distilled water during the experiment. The experimental pregnant females were left until delivery, and then, the development of their offspring was monitored for 45 days. After rat pups were born, the following were recorded: pregnancy duration, litter size, dynamics of weight gain in the rat pups for 21 days, postnatal death during the first 30 days, the ratio of males and females in the litter, periods of eye opening, incisor eruption, detachment of the auricle, appearance of hair coat, descent of testicles, and opening of the vagina. Then we assessed the maturation rate of sensory-motor reflexes in the offspring obtained from the experimental and control groups, the emotional motor behavior and ability for fine coordination of movements in the offspring, and conducted the open field-2 test on day 45 after birth.Results and discussion. No negative effect was detected for supramolecular complex of ivermectin Aniverm-2.0% on the parameters of physiological development of the offspring of the experimental rats within 45 days after birth. The dynamics of their mass, developmental parameters, and formation of motor reflexes during the feeding period remained within the normal values. Developmental indicators of sensory motor reflexes in the control and experimental rat pups had no statistically significant differences.

THE USE OF CONE BEAM COMPUTED TOMOGRAPHY TO EVALUATE OF RESULTS OF THE RAPID EXPANSION OF THE HARD PALATE WITH DENTAL ANOMALIES

The crowding of the permanent incisors with accompanying rotations or anterior cross bite is commonly seen during eruption of the permanent lateral incisors. When crowding is limited to a few millimeters, sufficient space may allow normal growth, but when the upper jaw is narrow and crowding exceeds this amount, rapid expansion of the hard palate may be an effective method. The purpose of this study was to study the method of cone beam computed tomography to evaluate the results of rapid palatal expansion in the narrowing of the upper dentition and the lack of space for incisors and the reaction of intact permanent molars, when fixing the apparatus on primary second molars in the absence of posterior cross bite. The study involved 20 children (age 7-10 years) who were treated with the Haas apparatus. The Haas apparatus was fixed on the upper second primary molars and on the primary canines. Cone beam computed tomography was performed before and after palatal suture rupture. A decrease in incisor crowding was found in all patients. The width between the permanent molars in the diameter has increased significantly, the distance between the tops of the roots of the upper permanent molars has increased more than between the crowns of the teeth. Application of the method shows the possibility of expanding the sky in the transverse direction. The use of a Haas apparatus attached to primary teeth in early mixed dentition in the absence of posterior cross bite is effective and provides a pronounced planned transverse growth of the jaw and can be indicated to expand the anterior part of the upper jaw to eliminate crowding of the upper incisors. With rapid expansion, there are favorable spontaneous changes in the palatal vertical position of the maxillary permanent molars in the opposite direction of expansion and there is the potential to mimic the expected natural transverse growth. Fixation of the apparatus used for this procedure on the primary molars and keeping the permanent molars unused means the prevention of periodontal damage, loss of attachment, demineralization and external resorption of the roots of permanent molars.

A case report on growth modification using facemask therapy in the management of class III malocclusion in a young patient

Background: In a growing patient, orthopaedic treatment of skeletal Class III malocclusion is critical because it can prevent future orthodontic and surgical procedures. Graber’s stated that early treatment by growth modification during the eruption of incisors or before the maxillary incisors become locked behind the mandibular counterparts is more advantageous. Case Description: This case report describes the treatment of a child aged 10 years with skeletal Class III malocclusion. The treatment plan was carried out with the use of a facemask and the results were highly satisfactory resulting in improved facial esthetics, a skeletal Class I with a Dental Class I molar, and canine relationship, an ideal overjet and overbite. Conclusion: Thus, growth modification, if done in properly selected cases, alleviates the need for future orthodontic and surgical intervention. The patient is being monitored until the end of growth to ensure the stability of treatment results.

Poly(I:C)-induced maternal immune activation causes elevated self-grooming in male rat offspring: Involvement of abnormal postpartum static nursing in dam.

Introduction: Maternal immune activation (MIA) is closely related to the onset of autism-like behaviors in offspring, but the mechanism remains unclear. Maternal behaviors can influence offspring's development and behaviors, as indicated in both human and animal studies. We hypothesized that abnormal maternal behaviors in MIA dams might be other factors leading to delayed development and abnormal behaviors in offspring. Methods: To verify our hypothesis, we analyzed poly(I:C)-induced MIA dam's postpartum maternal behavior and serum levels of several hormones related to maternal behavior. Pup's developmental milestones and early social communication were recorded and evaluated in infancy. Other behavioral tests, including three-chamber test, self-grooming test, open field test, novel object recognition test, rotarod test and maximum grip test, were performed in adolescence of pups. Results: Our results showed that MIA dams exhibit abnormal static nursing behavior but normal basic care and dynamic nursing behavior. The serum levels of testosterone and arginine vasopressin in MIA dams were significantly reduced compared with control dams. The developmental milestones, including pinna detachment, incisor eruption and eye opening, were significantly delayed in MIA offspring compared with control offspring, while the weight and early social communication showed no significant differences between the two groups. Behavioral tests performed in adolescence showed that only male MIA offspring display elevated self-grooming behaviors and reduced maximum grip. Discussion: In conclusion, MIA dams display abnormal postpartum static nursing behavior concomitantly with reduced serum levels of testosterone and arginine vasopressin, possibly involving in the pathogenesis of delayed development and elevated self-grooming in male offspring. These findings hint that improving dam's postpartum maternal behavior might be a potential regime to counteract delayed development and elevated self-grooming in male MIA offspring.

Management of Horizontally Placed Supernumerary Tooth Obstructing Central Incisor Eruption: Case Report

Management of Horizontally Placed Supernumerary Tooth Obstructing Central Incisor Eruption: Case Report

Non-Surgical Management of the Gingival Smile with Botulinum Toxin A-A Systematic Review and Meta-Analysis.

Currently, concern about facial attractiveness is increasing, and this fact has led to orthodontics in adult patients being an increasingly demanded treatment, and with it, multi-disciplinary work. When it is caused by a vertical excess of the maxilla, the ideal solution is orthognathic surgery. However, in borderline cases and when the cause is hyperactivity of the upper lip levator muscle complex, alternative conservative solutions can be considered, such as the application of botulinum toxin A (BTX-A). Botulinum toxin is a protein produced by a bacterium and causes a reduction in the force of muscle contraction. The multi-factorial nature of the smile requires an individualized diagnosis in each patient, since there are multiple ways to treat the gummy smile (orthognathic surgery, gingivoplasty, orthodontic intrusion). In recent years, interest has grown in the simplest techniques that allow the patient to quickly return to their usual routine, such as lip replacement. However, this procedure shows recurrences in the first 6-8 post-operative weeks. The main objective of this systematic review and meta-analysis is to analyze the effectiveness of BTX-A in the treatment of gummy smile in the short term, to study its stability, and to evaluate potential complications. A thorough search of the PubMed, Scopus, Embase, Web of Science, and Cochrane databases and a grey literature search were conducted. The inclusion criteria were studies with a sample size greater than or equal to 10 patients with gingival exposure greater than 2 mm in smile, treated with BTX-A infiltration. Those patients whose exclusive etiology of their gummy smile was related to altered passive eruption, gingival thickening, or overeruption of upper incisors were excluded. In the qualitative analysis, the mean pre-treatment gingival exposure ranged between 3.5 and 7.2 mm, reaching a reduction of up to 6 mm after infiltration with botulinum toxin at 12 weeks. Although multiple muscles are involved in the facial expression, the muscles par excellence selected for blockade with BTX-A were levator labii superioris, levator labii superioris ala nasalis, and zygomaticus minor, infiltrating from 1.25 to 7.5 units per side. In the quantitative analysis, the difference in mean reduction between both groups was -2.51 mm at two weeks and -2.24 mm at three months. The benefit of BTX-A in terms of improvement of gummy smile is demonstrated, as a significant reduction in gummy smile is estimated by BTX-A therapy two weeks after its application. Its results gradually decrease over time, however, they stay satisfactory without returning to their initial values after 12 weeks.

Mixed reality for extraction of maxillary mesiodens

BackgroundMesiodentes are the most common supernumerary teeth. The cause is not fully understood, although proliferations of genetic factors and the dental lamina have been implicated. Mesiodentes can cause delayed or ectopic eruption of permanent incisors, which can further alter occlusion and appearance. Careful attention should be paid to the position and direction of the mesiodentes because of possible damage to adjacent roots in the permanent dentition period, errant extraction in the deciduous and mixed dentition periods, and damage to the permanent tooth embryo. To avoid these complications, we applied mixed reality (MR) technology using the HoloLens® (Microsoft, California). In this study, we report on three cases of mesiodentes extraction under general anesthesia using MR technology.ResultsThe patients ranged in age from 6 to 11 years, all three were boys, and the direction of eruption was inverted in all cases. The extraction approach was palatal in two cases and labial in one case. The average operative time was 32 min, and bleeding was minimal in all cases. No intraoperative or postoperative complications occurred. An image was shared preoperatively with all the surgeons using an actual situation model. Three surgeons used Microsoft HoloLens® during surgery, shared MR, and operated while superimposing the application image in the surgical field.ConclusionsThe procedure was performed safely; further development of MR surgery support systems in the future is suggested.

Alloparental Care and Postnatal Development of Heterozygous TPH2 Transgenic Mice

The issue of the relationship between the transmission of a negative effect from a depressed mother to her offspring is one of the priorities in modern psychiatry. Mice with the knocked-out tryptophan hydroxylase-2 (TPH2) gene have a depressive-compulsive phenotype, which makes these animals a highly appropriate bio-model for studying the role of serotonin in the body. In the offspring of such animals the following reproductive parameters were studied: pups maturation (physiological development) and sensory and motor reflexes. It was found that in the heterozygous mice, maternal care was reduced by the TPH2 gene knockout and canibalism directed at offspring was increased. Deviations and violations in the return of pups to the nest were revealed in maternal behavior. Some deficiency in the development of heterozygous offspring was observed after 10 days. The homozygous (KO) pups had a lower body mass than the heterozygous (Het) and wild-type (Wt) pups. The rate of detachment of the auricle, eruption of the upper incisors, opening of the eyes, and lowering of the testes in the KO pups were observed at the same time as in the Wt and Het pups.

Management of an impacted maxillary central incisor with surgical exposure and a 2x4 orthodontic appliance: A case Report

Dental impaction or transposition are disorders related to ectopic eruption or failure in tooth eruption, which can affect child physical, mental, and social development. This condition compromises face aesthetics, phonation, and masticatory function. The cause of impaction may vary from physical obstruction in the path of eruption, tooth material arch length discrepancy to malformation of the tooth, but supernumerary teeth are the leading cause. Failure of eruption of maxillary incisors requires early diagnosis and proper treatment planning. General principles of management of the condition include removal of physical obstruction, creation of space, and surgical exposure with or without traction. The rationale of the 2x4 orthodontic treatment of an unerupted tooth depends upon its age, position, etiology, and amount of space in the dental arch. It under the category of interceptive orthodontic procedure to prevent malocclusion near future. The present case report elaborates on case of incisor impaction with different aetiologies and varying ranges of complexity. However, it's far frequently important to continue with a surgical–orthodontic treatment. The inclination of teeth in relation to the midline and the root maturation degree determine prognosis and therapeutic timing. Thus, we are describing a case of 10 yrs. old child with, class 1 molar relationship bilaterally with missing maxillary right central incisor.

Prenatal zestoretic exposure ameliorates developmental landmarks in rat offspring

Zestoretic, a combination of lisinopril and hydrochlorothiozide used as anti-hypertension drug prescribed even during pregnancy. Role of zestoretic on the developmental landmars of young ones exposed prenatally are yet to be established. Hence, the present investigation initiated to test in Wistar rats. Three groups of inseminated female rats were oral gavaged with zestoretic (lisinopril varied concentrations + hydrochlorothiozide 12.5mg) 25, 50 and 100 mg/Kg body weight (BW) on gestation days 7, 9, 11 and 13, whereas control group with double distilled water. Clinical toxicity found in few dams from 50 and 100 mg/Kg BW received rat shown aggressive behavior during experimentation. The developmental landmarks, such as pinna attachment, ear opening, fur development, eye opening, upper and lower incisor eruption, crown rump length, vaginal opening and testes descend were measured periodically on their postnatal days in all the young ones. The number of live pups in zestoretic 50, 100 mg/Kg BW administered females are significantly less (P

Microbiota of preterm infant develops over time along with the first teeth eruption.

The temporal growth of the infant microbiome in the early years of life influences short- and long-term infant health. The aim of this longitudinal study was to investigate bacterial dynamics in the microbiome of preterm infants during tooth eruption. Saliva samples from normally delivered (n = 24) and preterm infants (n = 31) were collected 30 days after birth and after the eruption of two primary mandibular incisors. Based on Illumina MiSeq Sequencing of the 16S rRNA gene, the dynamic microbial changes of newborns at two-time points were investigated. Meanwhile, the Human Oral Microbiome Database was adopted for assigning taxonomy. Using alpha and beta diversity analyses, different shift patterns of microbiome structures in preterm and healthy participants and bacterial diversity over time were observed. The relative abundance and shifts trend, along with the two lower primary central incisors eruption, of core oral flora varies in full-term and preterm groups, including Gemella spp., Rothia mucilaginosa, Veillonella atypica, etc. Several microorganisms colonize later in the oral microbiome development of premature babies, such as Gemella spp. In addition to teeth eruption, the growth of the saliva microbiome in preterm infants could be influenced by breastfeeding durations and birth weight. This study provided insights into how the oral microbiota changes during tooth eruption in preterm infants and how the colonization of the oral cavity with bacteria in preterm infants differs significantly from that in full-term infants.

Prevalence of Delayed Eruption of Permanent Upper Central Incisors at a Tertiary Hospital in Riyadh, Saudi Arabia.

Tooth eruption is defined as the axial movement of the tooth from its site of development in the alveolar bone to its functional position in the oral cavity. A delay in eruption can directly affect the accurate diagnosis, overall treatment planning, and timing of treatment. Thus, Delayed Tooth Eruption can have a significant impact on a patient's proper health care. This study aimed to estimate the prevalence of delayed eruptions of permanent upper central incisors in Riyadh, Saudi Arabia. A retrospective study assessed panoramic radiographs of children between the ages of 6-10 years old who attended the Dental University Hospital clinics at King Saud University in Riyadh, Saudi Arabia between 2014 and 2020. The radiographs were collected and examined to detect any delayed eruption of the permanent upper central incisors. Panoramic radiographs with delayed erupted permanent upper central incisors were identified by tooth developmental stages and eruption sequence. Of the 745 radiographs, 23 (3.09%) presented at least one delayed erupted permanent upper central incisor of which boys and girls comprised 16 (69.5%) and 7 (30.4%), respectively. Retained primary teeth was the most causative factor of delayed eruption (43.4%), followed by the early loss of primary teeth (21.7%) and insufficient arch space. The present study is the first to assess the prevalence of delayed eruption of the permanent upper central incisors on a Saudi population. Boys were found to have more prevalence of delayed eruption of the permanent upper central incisors compared to girls. Clinicians should be aware of such a condition as early diagnosis of delayed eruption is essential for providing optimal dental care.

A Survey of Bone Grafting Practice Patterns in North American Cleft Surgeons.

Alveolar bone grafting aims to restore bony continuity of the alveolus and provide optimal periodontal support for teeth adjacent to the cleft. We created a survey of cleft surgeons to assess the current standard of care regarding this procedure. A multiple choice survey was implemented using Qualtrics software and emailed to a list of 708 surgeons from the ACPA membership directory. Correlation between various provider factors and treatment practices was assessed with Fisher's exact test and likelihood ratio tests. The response rate was 17.5%. Eighty-seven percent of providers preferred to perform grafts prior to secondary canine eruption while 10% favored before central incisor eruption. Eighty-one percent favored palatal expansion prior to bone grafting. Wide variability existed regarding the time to initiate postoperative orthodontics; 43% waited 4 to 6 months. Sixty-four percent of surgeons now utilize cone beam CT to assess graft take. The majority of respondents utilized cancellous bone autograft (92%) from the anterior iliac crest (97%) as graft material. Seventy percent used three or more modalities for post-operative pain control management. Early career surgeons (0-5 years) appeared more likely to use non-autologous materials (p < .01) for grafting. Alveolar bone grafting prior to secondary canine eruption remains the most common strategy but other protocols are employed. Surgeons utilize multiple modalities for radiographic evaluation and most often use autologous cancellous bone as the primary grafting material. There is no true consensus on the perioperative timing and sequencing of orthodontic manipulation while principles of multimodal perioperative pain control appear widely accepted.

Lip Bumper Therapy Does Not Influence the Sagittal Mandibular Incisor Position in a Retrospective CBCT Study.

Lip bumper (LB) therapy is used as a treatment approach for mild to moderate crowding without extraction of teeth. Previous studies demonstrated that LB increases arch length through molar uprighting and lateral expansion. However, the effects of LB on mandibular incisors are inconclusive. The controversial results from different studies may be due to limitations including absence of a control group and/or use of 2D radiography. To address this issue, the current retrospective longitudinal CBCT study compared a rapid maxillary expansion (RME) group with no lower treatment [16 patients (9 females, 7 males); median age 8.86 years at T1 and 11.82 years at T2] and an RME + LB group [18 patients (13 females, 5 males); median age 9.46 years at T1 and 12.10 years at T2]. The CBCTs taken before and after phase 1 treatment were 3D superimposed based on the mandibular structure and were measured to determine the angular and linear changes of the mandibular incisors over the course of LB treatment. For comparisons between different timepoints within a group, a Wilcoxon matched-pairs signed rank test was used. For intergroup comparisons, a Mann–Whitney U test was used. Both groups showed eruption and protrusion of the mandibular incisors during the observation period, while there was no significant change in proclination of the lower incisors. When comparing the discrepancy of change between groups, there was no statistically significant difference detected. In summary, by utilizing a longitudinal 3D database, the current study demonstrated that the effect of LB on the position of the mandibular incisors is limited.

The Role of Lead Toxicity on Eruption Rate of Hypofunctional Incisors in Albino Wistar Rats

OBJECTIVES This objective of this study was to evaluate the role of a heavy metal- lead acetate in the eruption rate of hypo functional incisors in albino Wistar rats. METHODOLOGY An experimental study was done in animal house of Post Graduate Medical Institute, Lahore since March 2019 to March 2020. 34 adult albino Wistar rats were randomly divided into two groups (n=17 for each group) i.e., control and lead acetate group. Right mandibular incisors were selected for this study. Selected incisors were marked 1mm above the level of gingival papillae. The incisors were cut above this mark to make it hypo-functional. The readings were measured by digital Vernier caliper. This was considered as day 0. Incisors length was measured at day 0, 3, 6, 12 and 15 and eruption was calculated. The data was analyzed using SPSS version 22. RESULTS Eruption rate was similar throughout the study except last follow up. At the end of this study eruption of incisors in albino Wistar rats in control was 03.30±0.72mm, in lead 02.43±1.19mm. At day 15, the difference between control and lead group was statistically significant (p-value 0.033). CONCLUSION These results reveal that besides other causes of delayed tooth eruption excessive lead intoxication are also acausative factor of delayed tooth eruption.