Efficacy of Visual Oral Health Reinforcement in Reducing Plaque Accumulation and Gingival Bleeding: A Pilot Randomized Controlled Trial.

AIM: To compare oral hygiene (OH) differences during verbal or video OH instructions with or without images displaying poor oral health consequences. MATERIALS AND METHODS: Twenty-one healthy females (18-30 years) were randomly and equally divided into three intervention OH instruction groups: (1) verbal, (2) video-based, (3) video-based with image displaying the consequences of poor OH. Gingival bleeding on probing (BOP), gingival bleeding index (BI), and plaque score (PS) were assessed at baseline and after 4 weeks. Within- and between-group differences were assessed by non-parametric tests. RESULTS: Plaque score only showed a statistical group difference after follow-up [H(2) = 9.214, p = 0.01]. The post hoc test revealed that group III showed a significantly lower PS than groups I and II (p = 0.04 and p = 0.017, respectively). No differences were observed in PS between groups I and II. Group I showed no follow-up reduction in PS, BI, and BOP, while group II showed a statistically significant reduction in BI only after follow-up (p = 0.028). However, group III showed a statistically significant reduction in BOP and PS (p = 0.023 and p = 0.045, respectively) but not BI. CONCLUSIONS: Verbal and video-alone OH instructions similarly affect gingival health, while participants who were exposed to images displaying the severe OH consequences had lower PS than verbal or video-alone groups. CLINICAL SIGNIFICANCE: The mode of OH instructions is not influential for optimum oral health. However, employing visuals highlighting the severe consequences of poor OH leads to short-term reduction of plaque accumulation. How to cite this article: Aleid AA, Alnowaiser A, AlSakakir A, et al. Efficacy of Visual Oral Health Reinforcement in Reducing Plaque Accumulation and Gingival Bleeding: A Pilot Randomized Controlled Trial. J Contemp Dent Pract 2024;25(2):186-190.

Incidence and influential factors in pulp necrosis and periapical pathosis following indirect restorations: a systematic review and meta-analysis.

BACKGROUND: Restoring vital teeth with indirect restorations may threaten dental pulp integrity. However, the incidence of and influential factors on pulp necrosis and periapical pathosis in such teeth are still unknown. Therefore, this systematic review and meta-analysis aimed to investigate the incidence of and influential factors on pulp necrosis and periapical pathosis of vital teeth following indirect restorations. METHODS: The search was conducted in five databases, using MEDLINE via PubMed, Web of Science, EMBASE, CINAHL, and Cochrane Library. Eligible clinical trials and cohort studies were included. The risk of bias was assessed using Joanna Briggs Institute's critical appraisal tool and Newcastle-Ottawa Scale. The overall incidences of pulp necrosis and periapical pathosis following indirect restorations were calculated using a random effects model. Subgroup meta-analyses were also performed to determine the potential influencing factors for pulp necrosis and periapical pathosis. The certainty of the evidence was assessed using the GRADE tool. RESULTS: A total of 5,814 studies were identified, of which 37 were included in the meta-analysis. The overall incidences of pulp necrosis and periapical pathosis following indirect restorations were determined to be 5.02% and 3.63%, respectively. All studies were assessed as having a moderate-low risk of bias. The incidence of pulp necrosis following indirect restorations increased when the pulp status was objectively assessed (thermal/electrical testing). The presence of pre-operative caries or restorations, treatment of anterior teeth, temporization for more than two weeks, and cementation with eugenol-free temporary cement, all increased this incidence. Final impression with polyether and permanent cementation with glass ionomer cement both increased the incidence of pulp necrosis. Longer follow-up periods (> 10 years) and treatment provided by undergraduate students or general practitioners were also factors that increased this incidence. On the other hand, the incidence of periapical pathosis increased when teeth were restored with fixed partial dentures, the bone level was < 35%, and the follow-up was > 10 years. The certainty of the evidence overall was assessed as low. CONCLUSIONS: Although the incidences of pulp necrosis and periapical pathosis following indirect restorations remain low, many factors affect these incidences that should thus be considered when planning indirect restorations on vital teeth. DATABASE REGISTRATION: PROSPERO (CRD42020218378).

International trends of orthodontic publications: A bibliometric observational study of the last decade (2011-2020).

INTRODUCTION: The number of published orthodontic studies has increased considerably over the past ten years. OBJECTIVE: To analyze the bibliometric data of international orthodontic studies included in orthodontic journals encompassed by the Scopus database between 2011 and 2020, as well as to undertake data comparison between the period 2010-2015 and the period 2016-2020. MATERIALS AND METHODS: A retrospective search was conducted on 14 orthodontic journals included in the Scopus database from 2011 to 2020. Studies of both primary and secondary types were targeted by the search. The yearly number of studies published in the 14 journals, and the first 20 countries, institutions and their type (public/private), and authors, respectively, regarding publication volume, were presented. RESULTS: Over the past ten years, the number of publications in the chosen journals reached 9200, where the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist topped the journal list, with 22% and 12% of the publications, respectively. Furthermore, the orthodontic publication volume showed a declining trend by the end of the decade (-9%), where academic/public institutions produced most of the orthodontic studies, and the US (20%), Brazil (17%), and South Korea (8%) topped the countries with the most orthodontic studies. A comparison of the two halves of the decade revealed that orthodontic research exhibited an increasing trend in developing nations, especially Egypt (104%), Saudi Arabia (88%), and Iran (83%). CONCLUSION: The orthodontic studies published in the chosen journals over the past ten years showed a dynamic change in yearly publication and ranking of countries, institutions, and authors.

Assessment of masticatory function in older individuals with bimaxillary implant-supported fixed prostheses or with a natural dentition: A case-control study.

STATEMENT OF PROBLEM: A clinical assessment of the masticatory performance of edentulous people treated with bimaxillary implant-supported fixed prostheses is lacking. PURPOSE: The purpose of this case-control study was to compare the masticatory performance of edentulous people treated with bimaxillary implant-supported fixed prostheses to that of those with a natural dentition by using a simplified comminution test with hard viscoelastic test food and a mixing ability test. MATERIAL AND METHODS: Thirty-six participants were recruited and divided into 2 equal groups (n=18) based on their dental status. The experimental group (7 women, mean ±standard deviation age=69.8 ±7.5 years) had bimaxillary implant-supported fixed prostheses, and the control group (9 women, mean ±standard deviation age=68.3 ±5.6 years) had a natural dentition. A hard viscoelastic food comminution test and a mixing ability test with 2-colored chewing gum were performed in both groups. The number and total area of the particles during the comminution test and the variance of hue during the mixing ability test were measured. The data were analyzed with the parametric (paired t test) and nonparametric (Mann-Whitney U) tests to assess differences between the groups (α=.05). RESULTS: The experimental group exhibited significantly fewer pieces in the food comminution test than the control group (P=.001). The experimental group also showed significantly higher variance of hue values than the control group (P<.001). CONCLUSIONS: Patients treated with bimaxillary implant-supported prostheses had reduced masticatory performance in comparison to those with a natural dentition, despite having been provided with satisfactory and well-functioning prostheses.

Subjective and objective evaluation of masticatory function in patients with bimaxillary implant-supported prostheses.

BACKGROUND: People perform poorly in masticatory function tests despite well-functioning prostheses. However, it is unclear whether there is an agreement between subjective and objective measures of mastication. OBJECTIVES: To investigate the association between subjective and objective measures of masticatory function in patients with bimaxillary implant-supported prostheses. MATERIALS AND METHODS: An experimental group (n = 25, age = 70.6 ± 7.5 years, eight women) with bimaxillary implant-supported fixed prostheses and a control group (n = 25, age = 69.0 ± 5.3, 13 women) with natural dentition were recruited. The participants in the experimental group were included if they had been using the prosthesis for at least a year and had no obvious complaints with their prostheses. The control group was people with natural dentition and without any prostheses or complaints related to the masticatory system. The masticatory function was evaluated objectively with food comminution and mixing ability tests, and subjectively with jaw function limitation scale (JLFS) and oral health impact profile (OHIP). RESULTS: The experimental group performed poorly in both objective tests (p < .001). However, there was no significant differences between the two groups in total JFLS (p = .114) and OHIP (p = .312) scores. Though, there were certain positive correlations between the food comminution test and JFLS subdomains in the control group, and a positive correlation between food comminution test and specific subdomains of OHIP in the experimental group indicating poor correlation between the subjective and objective measures. CONCLUSION: Although patients with implant prostheses show poor masticatory performance, there is no agreement in the objective and subjective measures of mastication.

International trends of orthodontic publications: A bibliometric observational study of the last decade (2011-2020)

ABSTRACT Introduction: The number of published orthodontic studies has increased considerably over the past ten years. Objective: To analyze the bibliometric data of international orthodontic studies included in orthodontic journals encompassed by the Scopus database between 2011 and 2020, as well as to undertake data comparison between the period 2010-2015 and the period 2016-2020. Materials and methods: A retrospective search was conducted on 14 orthodontic journals included in the Scopus database from 2011 to 2020. Studies of both primary and secondary types were targeted by the search. The yearly number of studies published in the 14 journals, and the first 20 countries, institutions and their type (public/private), and authors, respectively, regarding publication volume, were presented. Results: Over the past ten years, the number of publications in the chosen journals reached 9200, where the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist topped the journal list, with 22% and 12% of the publications, respectively. Furthermore, the orthodontic publication volume showed a declining trend by the end of the decade (-9%), where academic/public institutions produced most of the orthodontic studies, and the US (20%), Brazil (17%), and South Korea (8%) topped the countries with the most orthodontic studies. A comparison of the two halves of the decade revealed that orthodontic research exhibited an increasing trend in developing nations, especially Egypt (104%), Saudi Arabia (88%), and Iran (83%). Conclusion: The orthodontic studies published in the chosen journals over the past ten years showed a dynamic change in yearly publication and ranking of countries, institutions, and authors.

RESUMO Introdução: O número de estudos publicados na área da Ortodontia aumentou consideravelmente nos últimos dez anos. Objetivos: Analisar os dados bibliométricos dos estudos ortodônticos internacionais publicados entre 2011 e 2020 em periódicos ortodônticos da base de dados Scopus, bem como realizar a comparação entre os dados dos períodos 2010-2015 e 2016-2020. Material e Métodos: Uma pesquisa retrospectiva foi realizada em 14 periódicos ortodônticos incluídos na base de dados Scopus de 2011 a 2020. Estudos dos tipos primários e secundários foram incluídos na pesquisa. Foram apresentados o número anual de estudos publicados em 14 revistas e os 20 primeiros países, instituições e seu tipo (público/privado) e autores, respectivamente, em relação ao volume de publicações. Resultados: Nos últimos dez anos, o número de publicações nos periódicos escolhidos chegou a 9.200, e o American Journal of Orthodontics and Dentofacial Orthopedics e o Angle Orthodontist lideraram a lista de periódicos, com 22% e 12% das publicações, respectivamente. Além disso, o volume de publicações ortodônticas apresentou uma tendência de queda no final da década (-9%), sendo que as instituições acadêmicas/públicas produziram a maior parte dos estudos ortodônticos, e os EUA (20%), Brasil (17%) e a Coreia do Sul (8%) lideraram os países com mais estudos ortodônticos. Uma comparação das duas metades da década revelou que a pesquisa ortodôntica exibiu uma tendência crescente nos países em desenvolvimento, especialmente Egito (104%), Arábia Saudita (88%) e Irã (83%). Conclusão: Os estudos ortodônticos publicados nos últimos dez anos nos periódicos escolhidos mostraram uma mudança dinâmica na publicação anual e no ranking de países, instituições e autores.

Efficacy of different dexamethasone routes and doses in reducing the postoperative sequelae of impacted mandibular third-molar extraction: A network meta-analysis of randomized clinical trials.

BACKGROUND: The aim of this network meta-analysis was to assess the comparative effects of different dexamethasone (DXM) routes and doses on reducing postoperative sequelae (pain, swelling, trismus) after surgical extraction of impacted mandibular third molars. METHODS: Five databases were searched on September 22, 2021, for randomized controlled trials. Risk of bias (ROB) was assessed using the Cochrane ROB 2 tool. Study heterogeneity, publication bias, and quality of evidence were investigated. Network meta-analyses were conducted (P < .05), and the P-score was used to rank comparisons of DXM doses and routes. RESULTS: Thirty-four eligible studies were included. Eight studies had low ROB, 21 had some concerns, and 5 had high ROB. The certainty of evidence evaluated by the Confidence in Network Meta-Analysis tool indicated low to very low certainty in most comparisons. The results showed that most DXM route and dose combinations were superior to a placebo in reducing the postoperative sequelae 1 day after surgical extraction. The results also showed that a 4-mg DXM submucosal injection substantially reduces pain 3 days after extraction compared with a 4-mg twin-mix or 8-mg intramuscular injection. Overall, it appears that 4 mg DXM submucosal injection or admixed with local anesthetic is effective in reducing postoperative sequelae after surgical extraction. CONCLUSIONS: Within the limitations of this study, the administration of DXM appears to be effective in reducing the postoperative sequelae, especially in the submucosal route. However, no noteworthy differences were found between the investigated DXM route and dose comparisons. PRACTICAL IMPLICATIONS: Submucosal DXM injection effectively reduce postoperative sequelae of third-molar extractions.

Chewing and its influence on swallowing, gastrointestinal and nutrition-related factors: a systematic review.

The study aimed to evaluate the hypothesis that chewing is a mechanical and physiological contributor to swallowing, physiologic/pathologic processes of the gastrointestinal tract (GIT), and nutrition-related factors. A search strategy was applied to three different databases to investigate if chewing function in adults affects the swallowing, physiologic/pathologic processes of the GIT, and nutrition-related factors compared to controls with no exposure. The included studies were evaluated for methodological quality and risk of bias and certainty of evidence. The results showed 71 eligible studies. Overall, the results showed that 46 studies supported the hypothesis while 25 refuted it. However, the GRADE analysis showed low to very low certainty of the evidence to support the hypothesis that chewing is an important contributor in the swallowing process, and physiologic/pathologic processes in the GIT. The GRADE analysis also showed a moderate to very low certainty of the evidence to suggest that chewing function contributes to nutrition-related parameters. The overall results of the current study showed that a majority (64.7%) of the studies (46 out of 71) supported the hypothesis. However, robust studies with proper design, adequate sample size, and well-defined outcome parameters are needed to establish conclusive evidence.

The Association of Dental Pulp Stones to Cardiovascular and Renal Diseases: A Systematic Review and Meta-Analysis.

BACKGROUND: Pulp stone (PS) is a dystrophic calcification in the tooth's pulp chamber and was suggested in the literature to be associated with other calcifications in the body. This study aimed to investigate the association of PS to cardiovascular diseases (CVD) and renal stones (RS). METHODS: Three databases were searched until June 2021 in addition to manual searching of Google Scholar and grey literature. Original studies were only included and critically appraised using an adapted version of the Newcastle-Ottawa scale. The odds ratio (OR) effect measure was calculated using the Mantel-Haenszel statistical test (95% confidence interval [CI]) to investigate the association of PS with CVD and or RS (P value ˂ .05). RESULTS: The database search identified 4933 studies, and 19 studies were finally included. The risk of bias was low in 13 studies, moderate in 4 studies, and high in 2 studies. The meta-analysis of the moderate and low risk of bias studies revealed a significant association between PS and CVD (OR, 3.35; 95% CI, 1.91-5.89; P < .001, I2 = 65%), but no association was found between PS and RS. The results also revealed an association between PS and CVD in patients older than 40 (OR, 8.78; 95% CI, 3.64-21.17; P < .001, I2 = 0%). CONCLUSIONS: The current study results showed an association between PS and CVD, but no association was found between PS and RS. PS in patients older than 40 years, compared with younger patients (<40 years), was associated with CVD.

Effect of apical microsurgery on force regulation of incisor teeth during unpredictable force control task.

BACKGROUND: Apical microsurgery (AMS) involves removal of the root-end which can affect the force regulation of teeth. OBJECTIVE: To investigate the force regulation of incisor teeth treated with AMS during the unpredictable force control task in comparison with their contralateral teeth with complete root apices, in humans. METHODS: Fifteen eligible participants (8 women and 7 men; mean age 52.9 ± SD 4.4 years) performed a standardised unpredictable force control task, which involved pulling and holding a force transducer with AMS-treated incisors and their contralateral control teeth (n = 30 teeth). A series of four load masses: 100, 200, 50 and 300 gm were attached to the force transducer through a string in an unpredictable manner. The obtained force profile was divided into initial and later time-segments. The peak force and peak force rate during the initial time-segment, and the holding force and coefficient of variability during the later time-segments were calculated and compared by the repeated measures analysis of variance. RESULTS: During the initial time-segment, the peak force and peak force rate were significantly lower in the AMS-treated teeth than in the controls (p = .001, p = .013, respectively). However, during the later time-segment, no significant differences in the holding force nor the coefficient of variability were observed between the AMS-treated teeth and their controls (p = .755, p = .213, respectively). CONCLUSION: In contrast to incisors with complete normal root apices, AMS-treated incisors do not show robust changes in force regulation.

Motor Performance and Skill Acquisition in Oral Motor Training With Exergames: A Pilot Study.

Objective: To investigate the effects of oral-motor training with exergames on motor performance and motor skill acquisition in two different age groups. Methods: Thirty-two healthy participants were recruited in the current pilot study and divided equally into two groups (Gen Z and Baby Boomers) according to their age. A pair of electromyographic (EMG) electrodes were placed on the participants' masseter muscles. The EMG device communicated via Bluetooth with a mobile video game in response to the electromyographic activity of the masseter muscles during clenching. During the experimental session, participants were asked to play a video game in five blocks of 5 min each, with a 3-min break between each time block. The goal of the game was to collect as many coins (game points) as possible and to dodge/avoid upcoming obstacles (game life). Motor performance was assessed by performance scores and the number of game lives. Skill acquisition was measured by task efficiency (ratio of performance scores and number of game lives) across time blocks. Results: The results of the study showed significantly lower performance scores (p < 0.001), a higher number of game lives (p < 0.001), and lower task efficiency in the Baby Boomer group compared to the Gen Z group. Specifically, the results showed that there was a significant difference in task efficiency between the first and second, third and fourth, fourth- and fifth-time blocks in the Gen Z group (p < 0.002). However, there was only a significant difference between first- and second-time blocks in the Baby Boomer group (p = 1.012), suggesting that skill acquisition in the Baby Boomer group did not change significantly over the course of the time blocks. Conclusion: The study showed higher motor performance and superior motor skill acquisition with novel exergame training in the Gen Z group compared to the Baby Boomer group. The results of the study indicate that there is an improvement in oral motor skills with short-term training, yet the differences in oral motor skills between the two groups are still evident. The Baby Boomer group, unlike the Gen Z group, did not show robust improvement in task efficiency over the course of the series.

A Nation-wide Prevalence of Malocclusion Traits in Saudi Arabia: A Systematic Review.

Objectives: The aim of this article is to establish a comprehensive nation-wide prevalence of malocclusion traits on the sagittal, vertical, and transverse planes of space in Saudi Arabia. Materials and Methods: A systematic search was conducted in three databases (Medline via PubMed, Embase, and Web of Science) and complemented with a manual search of Google Scholar and the reference list of included studies. Original studies of Saudi Arabian healthy individuals at any age were included. The quality and the risk of bias of the included studies were assessed using the Joanna Briggs Institute's appraisal tool. The data about the selected malocclusion traits on the sagittal, vertical, and transverse planes of space were extracted and pooled. Results: Out of 7163 identified titles, 11 studies were finally included. The risk of bias was high in two studies, moderate in eight studies, and low in one study. The studied age groups were from early childhood to late adulthood, with a total sample size of 19,169 participants. The majority of the studies recruited their sample from school/public sources, whereas the remaining three studies recruited their sample from dental (non-orthodontic) clinics. Conclusions: Within the limitations of this study, pooled prevalence of Angle's Class I molar relation in Saudi Arabia was similar to other populations but Angle's Class II and Class III molar relations were lower and higher, respectively. These differences could be attributed to population-related differences in craniofacial morphology. Teeth crowding, teeth spacing, and midline shift, along with increased overjet and overbite, were among the most common malocclusion traits occurring in Saudi Arabia.

Effect of malocclusion on jaw motor function and chewing in children: a systematic review.

OBJECTIVE: To investigate the effects of dental/skeletal malocclusion and orthodontic treatment on four main objective parameters of chewing and jaw function (maximum occlusal bite force [MOBF], masticatory muscle electromyography [EMG], jaw kinematics, and chewing efficiency/performance) in healthy children. MATERIALS AND METHODS: Systematic searches were conducted in MEDLINE (OVID), Embase, and the Web of Science Core Collection. Studies that examined the four parameters in healthy children with malocclusions were included. The quality of studies and overall evidence were assessed using the Joanna Briggs Institute and GRADE tools, respectively. RESULTS: The searches identified 8192 studies; 57 were finally included. The quality of included studies was high in nine studies, moderate in twenty-three studies, and low in twenty-five studies. During the primary dentition, children with malocclusions showed similar MOBF and lower chewing efficiency compared to control subjects. During mixed/permanent dentition, children with malocclusion showed lower MOBF and EMG activity and chewing efficiency compared to control subjects. The jaw kinematics of children with unilateral posterior crossbite showed a larger jaw opening angle and a higher frequency of reverse chewing cycles compared to crossbite-free children. There was a low to moderate level of evidence on the effects of orthodontic treatment in restoring normal jaw function. CONCLUSIONS: Based on the limitations of the studies included, it is not entirely possible to either support or deny the influence of dental/skeletal malocclusion traits on MOBF, EMG, jaw kinematics, and masticatory performance in healthy children. Furthermore, well-designed longitudinal studies may be needed to determine whether orthodontic treatments can improve chewing function in general. CLINICAL RELEVANCE: Comprehensive orthodontic treatment, which includes evaluation and restoration of function, may or may not mitigate the effects of malocclusion and restore normal chewing function.

Oral Fine Motor Control of Teeth Treated with Endodontic Microsurgery: A Single-Blinded Case-control Study.

INTRODUCTION: Periodontal mechanoreceptors (PMRs) are refined neural receptors present in abundance at the root apex and have a pivotal role in oral fine motor control. This case-control study aimed to evaluate the oral fine motor control of teeth treated with endodontic microsurgery (EMS) in comparison with the control teeth using a standardized behavioral biting task. METHODS: Fourteen eligible participants performed 5 trials of an oral fine motor control task that involved holding and splitting half of a peanut positioned on a force transducer with their EMS treated tooth and its contralateral control incisor tooth (28 teeth in total). The outcome variables were the mean food holding force, intra- and intertrial variability of the holding force, food splitting force, splitting duration, and the frequency of the stepwise splitting phase. The data were analyzed with parametric and nonparametric tests. RESULTS: The results showed no statistically significant differences in the holding force, inter- and intratrial variability of the holding force, splitting force, or splitting duration between the teeth treated with EMS and the control (P > .05). However, there was a significantly higher frequency of stepwise ramp increase during the splitting phase with EMS treated teeth compared with the control (48% and 37%, respectively; P < .05). CONCLUSIONS: EMS treated teeth showed similar force regulation and oral fine motor control as the contralateral control. The findings of this study suggest that EMS treatment does not perturb the sensory information of PMRs and maintains the force regulation and oral fine motor control of the teeth.

Effect of food hardness on chewing behavior in children.

OBJECTIVE: To investigate the effects of food hardness on chewing behavior in children compared with adults. MATERIALS AND METHODS: Healthy children (3-17 years) were equally divided into five groups based on their dental eruption stages. Each participant ate soft and hard viscoelastic test food models (3 each), while the three-dimensional jaw movements and electromyographic (EMG) activity of the bilateral masseter muscles were recorded. The data from the children were compared with a control group of healthy adults (18-35 years). The data were analyzed with nonparametric tests. RESULTS: There was no significant difference in the number of chewing cycles and the duration of the chewing sequence between children groups and adults. Children with primary dentition (3-5 years) showed shorter lateral jaw movement and higher muscle activity at the end of the chewing sequence, compared with adults. Further, children's age-groups (3-14 years) failed to adapt their jaw muscle activity to food hardness. However, at the late-permanent dentition stage (15-17 years), children were capable of performing adult-like chewing behavior. CONCLUSIONS: Overall, it seems that children as young as 3-year-old are quite competent in performing basic chewing function similar to adults. Yet, there are differences in the anticipation or adaption of jaw muscle activity and jaw kinematics to food hardness. CLINICAL RELEVANCE: The study may have clinical implication in the diagnosis and management of children with chewing impairment associated with dental malocclusions and other orofacial dysfunctions.

Age-related changes in oral motor-control strategies during unpredictable load demands in humans.

To investigate age-related changes in oral motor strategies in response to unpredictable load demands. Sixty-five healthy children (aged 3-17 yr) were divided into five age-groups based on their dental eruption stages and compared with a group of healthy adults (aged 18-35 yr). Each participant was asked to perform a standardized motor control task involving 'pulling' and 'holding' a force transducer with the anterior teeth. Different loads were attached to the force transducer in an unpredictable manner. The temporal force profile was divided into two time-segments (an initial segment and a later segment). The peak force and peak force rate during the initial time-segment, and the holding force and intra-trial variability (coefficient of variation) during the later time-segment, were measured. The results showed no differences in the peak force, peak force rate, holding force, and force variability in children compared with adults. However, the trends in the data evaluated using a segmented regression analysis showed that a breakpoint (abrupt change) consistently occurred in the late-mixed dentition group (age 9-11 yr) for most of the outcome variables. The results indicate that while the motor control strategies in children appear to be similar to those in adults, there is a shift in the oral motor developmental trend during the late-mixed dentition stage.

Motor control strategies during unpredictable force control tasks in humans.

BACKGROUND: There are fundamental similarities and differences between the jaw and hand motor systems. However, it is unclear how the two systems respond to unpredictable task demands. OBJECTIVE: To investigate and compare the force control of the jaw motor system (OMS) and the hand motor system (HMS) during unpredictable load changes. METHODS: Seventeen healthy adults (24.0 ± 4.3 years) performed two standardised force control tasks (OMS and HMS). During the OMS, the participants asked to bite and pull a force transducer with the front teeth. While during HMS they pinched and pulled the same force transducer with their index and thumb fingers. Series of loads were added to a string attached to the transducer in an unpredictable (sequential and non-sequential) manner. The entire force profile during the task was divided into "initial" and "latter" segments. The force control was analysed and compared between the OMS and HMS in terms of peak force during the initial segment and holding force and force variability during the latter segment. RESULTS: The peak force, holding force and force variability were higher for the OMS than the HMS (P < .001). However, there were no differences in the peak force, holding force or force variability between the sequential and non-sequential load changes (P > .05). CONCLUSIONS: The results showed that unpredictable load changes did not affect the force control during the motor control task. This study suggests that both the motor systems are optimised in performing simple motor control tasks and are rather resilient to motor unpredictability.

Developmental and age-related changes in sensorimotor regulation of biting maneuvers in humans.

Previous studies indicated distinct differences in biting and chewing behaviors between children and adults. However, these studies used different methodologies and failed to study age-related changes in the fine motor control of biting from childhood to adulthood. Therefore, this study aimed to investigate age-related changes in oral fine motor control in healthy children in comparison to adults. Sixty-five healthy children (3-17 years) were equally divided into five age-groups based on their dental eruption stages. Each participant was asked to hold half a peanut rested on a force transducer between two opposing anterior teeth for 3-4 s before splitting it. The force applied on the transducer was continuously monitored and recorded during food holding and splitting. The data obtained from the children subgroups were compared to an adult group (18-35 years). Results showed that the force regulation during food manipulation was higher and more variable in children with primary to early-permanent dentition stages compared to adults. Additionally, children with primary and early-mixed dentition showed longer food splitting duration than adults and exhibited a predominantly step-wise ramp-increase of force. The results of the present study showed age-related changes in fine motor control of food biting maneuvers. The results of the study also suggested that younger children with primary dentition show signs of immature oral fine motor control. However, with an increase in age and the accompanying structural changes, the oral fine motor control eventually transits to a more matured "adult-like" biting maneuvers.

Effect of Chewing on the Expression of Salivary Protein Composition: A Systematic Review.

Salivary proteins have an imperative role in the maintenance of oral health and repairing mechanisms of injured tissues. However, there is paucity of information reported in the literature about the influence of chewing activities on the secretion or expression of salivary proteins. The purpose of this systematic review is to evaluate the effect of chewing on the expression of salivary proteins composition in healthy individuals. A thorough systematic search shows 14 eligible studies for the review. The results of the systematic review show the effect of chewing on total protein concentration, alpha-amylase (α-amylase), peroxidase, lysozyme, immunoglobulin A (IgA), and mucin. Six papers concluded that chewing has a little or no effect on total protein concentration, α-amylase, peroxidase, lysozyme, and IgA activities. Five papers reported a negative (decreasing) effect of chewing on the function of total protein, α-amylase, IgA, and mucin. Only two papers showed an increase in total protein and IgA function upon chewing stimulation. The results of this systematic review indicate that more standardized evidence-based research is required for better assessment of chewing effects on salivary proteins. Within the limitations of this review, the existing evidence suggests that chewing in healthy people has minimum effect on the expression and activities of salivary proteins.

Dental age comparison in patients born with unilateral cleft lip and palate to a control sample using Demirjian and Willems methods.

Objectives: To determine and compare the differences in dental age (DA) and chronological age (CA) of Demirjian and Willems methods in 9- to 11-year-old Caucasian boys and girls born with non-syndromic unilateral cleft lip and palate (NSUCLP) to an age-matched control group. Analysis of the results is undertaken to determine whether there are differences between gender, groups, and methods. Materials and methods: Dental panoramic tomograph (DPT) of 108 children with NSUCLP aged from 8.79 to 10.99 years (x¯=10.05 ±â€Š 0.36) were compared to 107 control children. Age, gender, and group were blinded during examination. The Demirjian and Willems methods were used by both authors to visually examine the radiographs. Differences between DA and CA were determined with a repeated two-way ANOVA. Results: Inter-examiner reliability was good (ICC ≈ 0.75). For each of the methods used, the mean DA/CA difference was greater in the control group than in the NSUCLP group (P = 0.011). The control group's Demirjian mean DA/CA difference was 1.08 years and Willems mean was 0.46 years, compared to the NSUCLP group's Demirjian mean DA/CA difference 0.83 years and Willems mean 0.22 years. Only the Willems method determined a statistically significant gender difference (P = 0.000). Conclusions: The null hypothesis was rejected. Willem's method as compared to Demirjian's displayed greater accuracy in estimating CA. Both methods overestimated CA but detected DA delay in NSUCLP children compared to the control group. However, the methods were inconsistent in estimating gender CA.