Long-term effects produced by early treatment of Class III malocclusion with rapid maxillary expansion and facemask followed by fixed appliances: A multicentre retro-prospective controlled study

OBJECTIVE

To assess the short- and long-term dentoskeletal effects of early Class III treatment with rapid maxillary expansion and facemask (RME/FM) followed by fixed appliances.

MATERIALS AND METHODS

A total of 44 patients (27 females, 17 males) treated consecutively with RME/FM were included from the archives of 3 centres. Three lateral cephalograms were available: T0 (before the start of RME/FM therapy, mean age 8.1 ± 1.8 years), T1 (immediately after RME/FM, mean age 9.8 ± 1.6 years), and T2 (long-term observation, mean age 19.5 ± 1.6 years). A control group of 17 untreated Class III subjects (12 females and 5 males) also was selected. Between-group statistical comparisons were performed with ANCOVA.

RESULTS

No statistically significant differences for any of the cephalometric variables were found at T0. In the short term, the treated group showed significant improvements in ANB (+2.9°), Wits appraisal (+2.7 mm), SNA (+1.8°) and SNB (-1.1°). A significant closure of CoGoMe angle (-1.3°) associated with smaller increments along Co-Gn (-2.4 mm) also was found together with a significant increase in intermaxillary divergence (+1.3°). In the long-term, significant improvements in ANB (+2.6°), Wits appraisal (+2.7 mm) and SNB (-1.7°) were recorded together with a significant closure of the CoGoMe angle (-2.9°). No significant long-term changes in vertical skeletal relationships were found.

CONCLUSIONS

RME/FM therapy was effective in improving Class III dentoskeletal relationships in the short term. These changes remained stable in the long-term due mainly to favourable mandibular changes.

Efficacy of an automatic electric toothbrush with nylon bristles in dental plaque removal: a cross-over randomized controlled trial

OBJECTIVES

The objective of this single-use, five-treatment, five-period, cross-over randomized controlled trial (RCT) was to compare the efficacy in dental plaque removal of a new Y-shaped automatic electric toothbrush (Y-brush) compared to a U-shaped automatic electric toothbrush (U-brush), a manual toothbrushing procedure (for 45 and 120 s), and no brushing (negative control).

MATERIALS AND METHODS

Eligible participants were volunteer students randomized to the treatments in the five periods of the study. The primary outcome measure was the reduction in full-mouth plaque score (FMPS) after brushing while the secondary outcome variable was a visual analogic scale (VAS) on subjective clean mouth sensation. Mixed models were performed for difference in FMPS and VAS.

RESULTS

After brushing procedures, manual toothbrushing (120 s) showed a statistically significant reduction in FMPS than Y-brush (difference 36.9; 95%CI 29.6 to 44.1, p < 0.0001), U-brush (difference 42.3; 95%CI 35.1 to 49.6, p < 0.0001), manual brushing (45 s) (difference 13.8; 95%CI 6.5 to 21.1, p < 0.0001), and No brushing (difference 46.6; 95%CI 39.3 to 53.9, p < 0.0001). Y-brush was significantly more effective than No brushing (difference 9.8; 95%CI 2.5 to 17.0, p = 0.0030), while there was no significant difference compared to U- brush. Similar results were obtained for the differences in the Clean Mouth VAS.

CONCLUSIONS

Y-brush was significantly more effective than no brushing (negative control) in removing dental plaque. When compared to manual toothbrushing for both 45 and 120 s, however, Y-brush was less effective in dental plaque removal.

CLINICAL RELEVANCE

Modified design of automatic toothbrushing devices could improve plaque reduction, especially in patients with intellectual disabilities or motor difficulties.

Clinical decision-making and management of stage IV periodontitis: A survey

OBJECTIVE

To investigate the clinical management of stage IV periodontitis patients among clinicians within the Italian Society of Periodontology and Implantology.

METHODS

A cross-sectional study was designed on a web-based anonymous survey. Comparison between ordinary members (OMs) versus active and certified members (ACMs) and comparison between members with at least 10 years of experience in periodontology (Ov10) and members with less than 10 years of experience in periodontology (Un10) were performed.

RESULTS

A total of 324 out of 1362 members (response rate of 24%) responded to the questionnaire. ACMs and Ov10 more often reported their teams hold adequate skills to manage cases. Step I and II periodontal therapy took more time in the ACMs and Ov10 groups. ACMs used different strategies to perform step I-II therapy, and antibiotics were used less frequently than OMs. Unresponsive sites were treated more often with surgery by ACMs compared to OMs. ACMs adopted different treatment sequences compared to OMs. Ov10 group used more often CBCT, lateral cephalogram, and wax-up while Un10 group tend to avoid orthodontic therapy.

CONCLUSIONS

More experienced members spent more time in step I and II of periodontal therapy, used more diagnostic tools, and performed more often surgery and orthodontics in the treatment of stage IV periodontitis patients.

Understanding Racial/Ethinic Disparities in COVID Mortality Using a Novel Metric: COVID Excess Mortality Percentage

Prior research on racial/ethnic disparities in COVID-19 mortality has often not considered to what extent they reflect COVID-19-specific factors, versus preexisting health differences. This study examines how racial/ethnic disparities in COVID-19 mortality vary with age, gender, and time period over April - December 2020 in the US, using mortality from other natural causes to proxy for underlying health. We study a novel measure, the COVID Excess Mortality Percentage (CEMP), defined as the COVID-19 mortality rate, divided by the non-COVID natural mortality rate, converted to a percentage, where the CEMP denominator, controls, albeit imperfectly, for differences in population health. Disparities measured using CEMP deviate substantially from those in prior research. In particular, we find very high disparities (up to 12:1) in CEMP rates for Hispanics versus Whites, particularly for non-elderly men. Asians also have elevated CEMP rates versus Whites, which were obscured in prior work by lower overall Asian mortality. Native Americans and Blacks have significant disparities compared to Whites populations, but CEMP ratios to Whites are lower than ratios reported in other work. This is because the higher COVID-19 mortality for Blacks and Native Americans comes partly from higher general mortality risk, and partly from COVID-specific risk.

Cephalometric changes of pushing splints 3 compared to rapid maxillary expansion and facemask therapy on the airway space in class III growing patients: A randomized clinical trial

BACKGROUND

Early orthopaedic treatment with rapid maxillary expansion (RME) associated with facemask (FM) has been shown to be effective in correcting Class III malocclusions in children. Treatment with pushing splints 3 (PS3) has shown to correct skeletal discrepancies in Class III growing patients. However, the effects of orthopaedic treatment on the upper airways in children with Class III malocclusion is controversial.

OBJECTIVES

The aim of this study was to evaluate the cephalometric changes in the airways of PS3 compared to the RME/FM protocol.

MATERIALS AND METHODS

In this study, 48 patients with Class III malocclusion (age range 5.5-8.5 years old) were selected for this study, and 24 were treated with PS3 appliance and 24 with RME/FM therapy. Lateral cephalograms before (T0) and at the end of the treatment (T1) were analysed to compare pharyngeal spaces. Paired and unpaired t tests were used for data analysis (P < .05).

RESULTS

A total of 41 patients (21 patients for the PS3 group, 11 males and 10 females, mean age 7.0 ± 1.2 years; 20 patients for the RME/FM group, 10 males and 10 females, mean age 7.2 ± 1.3 years) were included. The results showed a statistically significant (P < .05) increase in the nasopharyngeal space after both therapies. However, the effects were similar considering that there were no differences between groups for the assessed variables at T0-T1.

CONCLUSIONS

Early treatment of Class III malocclusion with PS3 does not induce a statistically significant increase in the sagittal airway space compared to RME/FM. The absence of untreated group could not define the role of growth in the increase of space.

Evidence on COVID-19 Mortality and Disparities Using a Novel Measure, COVID excess mortality percentage: Evidence from Indiana, Wisconsin, and Illinois

COVID-19 mortality rates increase rapidly with age, are higher among men than women, and vary across racial/ethnic groups, but this is also true for other natural causes of death. Prior research on COVID-19 mortality rates and racial/ethnic disparities in those rates has not considered to what extent disparities reflect COVID-19-specific factors, versus preexisting health differences. This study examines both questions. We study the COVID-19-related increase in mortality risk and racial/ethnic disparities in COVID-19 mortality, and how both vary with age, gender, and time period. We use a novel measure validated in prior work, the COVID Excess Mortality Percentage (CEMP), defined as the COVID-19 mortality rate (Covid-MR), divided by the non-COVID natural mortality rate during the same time period (non-Covid NMR), converted to a percentage. The CEMP denominator uses Non-COVID NMR to adjust COVID-19 mortality risk for underlying population health. The CEMP measure generates insights which differ from those using two common measures-the COVID-MR and the all-cause excess mortality rate. By studying both CEMP and COVID-MRMR, we can separate the effects of background health from Covid-specific factors affecting COVID-19 mortality. We study how CEMP and COVID-MR vary by age, gender, race/ethnicity, and time period, using data on all adult decedents from natural causes in Indiana and Wisconsin over April 2020-June 2022 and Illinois over April 2020-December 2021. CEMP levels for racial and ethnic minority groups can be very high relative to White levels, especially for Hispanics in 2020 and the first-half of 2021. For example, during 2020, CEMP for Hispanics aged 18-59 was 68.9% versus 7.2% for non-Hispanic Whites; a ratio of 9.57:1. CEMP disparities are substantial but less extreme for other demographic groups. Disparities were generally lower after age 60 and declined over our sample period. Differences in socio-economic status and education explain only a small part of these disparities.

Comparison of the effects on facial soft tissues produced by rapid and slow maxillary expansion using stereophotogrammetry: a randomized clinical trial

OBJECTIVE

To compare the effects on facial soft tissues produced by maxillary expansion generated by rapid maxillary expansion (RME) versus slow maxillary expansion (SME).

MATERIALS AND METHODS

Patients in the mixed dentition were included with a transverse discrepancy between the two arches of at least 3 mm. A conventional RME screw was compared to a new expansion screw (Leaf expander) designed to produce SME. Both screws were incorporated in a fixed expander. The primary outcome was the difference of the facial tissue changes in the nasal area measured on facial 3D images captured immediately before application of the expander (T0) and after one year of retention, immediately after the expander removal (T1). Secondary outcomes were soft tissue changes of other facial regions (mouth, lips, and chin). Analysis of covariance was used for statistical analysis.

RESULTS

Fourteen patients were allocated to the RME group, and 14 patients were allocated to the SME group. There were no dropouts. Nasal width change showed a difference between the two groups (1.3 mm greater in the RME group, 95% CI from 0.4 to 2.2, P = 0.005). Also, intercanthal width showed a difference between treatments (0.7 mm greater in the RME group, 95% CI from 0.0 to 1.3, P = 0.044). Nasal columella width, mouth width, nasal tip angle, upper lip angle, and lower lip angle did not show any statistically significant differences. The Y-axis (anterior-posterior) components of the nasal landmark showed a statistically significant difference between the two groups (0.5 mm of forward displacement greater in the RME group, 95% CI from 0.0 to 1.2, P = 0.040). Also, Z-axis (superior-inferior) components of the lower lip landmark was statistically significant (0.9 mm of downward displacement in favor of the RME group, 95% CI from 0.1 to 1.7, P = 0.027). All the other comparisons of the three-dimensional assessments were not statistically significant.

CONCLUSIONS

RME produced significant facial soft tissue changes when compared to SME. RME induced greater increases in both nasal and intercanthal widths (1.3 mm and 0.7 mm, respectively). These findings, though statistically significant, probably are not clinically relevant. Trial registration ISRCTN, ISRCTN18263886. Registered 8 November 2016, https://www.isrctn.com/ISRCTN18263886?q=Franchi&filters=&sort=&offset=2&totalResults=2&page=1&pageSize=10.

COVID-19 Boosters: If The US Had Matched Israel's Speed And Take-Up, An Estimated 29,000 US Lives Would Have Been Saved

Israel was the first country to launch COVID-19 boosters, in late July 2021, with strong public health messaging. The booster campaign reversed rising infection rates from the Delta variant and reduced hospitalizations and deaths. The US booster rollout was slower, and public health messaging was mixed. We used the Israeli experience to ask the counterfactual question: How many lives could the US have saved if it had authorized boosters sooner? We estimated that through June 30, 2022, if the US had moved at Israel's speed and booster take-up percentages, it would have saved 29,000 lives. US regulatory caution, in the middle of a pandemic, thus had a large, avoidable cost. Yet the US booster rollout still avoided 42,000 deaths. Moving more slowly to approve boosters, as some advocated, would have cost many additional lives.

Long-Term Assessment of Treatment Timing for Rapid Maxillary Expansion and Facemask Therapy Followed by Fixed Appliances: A Multicenter Retro-Prospective Study

BACKGROUND

to determine the role of treatment timing in the long-term effects produced by rapid maxillary expansion and facemask therapy (RME/FM) in Class III patients.

METHODS

This study compared two sample groups treated with RME/FM followed by fixed appliances: the early prepubertal group (EPG) (17 patients; mean age before treatment (T0), 5.8 ± 0.7 years; range, 4.3-6.9 years) and the late prepubertal group (LPG) (17 patients; mean age at T0, 10.1 ± 0.8 years; range, 9.0-11.1 years). Lateral cephalograms for the two groups were examined before treatment (T0) and at a long-term observation (T1) (EPG, 19.8 ± 1.0 years; LPG, 21.0 ± 2.1 years). Independent sample t-tests were performed to compare the two groups at T0 and T1.

RESULTS

No statistically significant differences were found for any of the cephalometric variables at T0, except for the total mandibular length, overjet, and inclination of the maxillary incisors to the palatal plane, which were greater in the LPG. At T1, no statistically significant differences were detected for any of the cephalometric variables.

CONCLUSIONS

There were no significant long-term differences when treating Class III patients with RME/FM, either during an early prepubertal phase (≤7 years of age) or during a late prepubertal phase (≥9 years of age).

Comparison between digital and conventional impression techniques in children on preference, time and comfort: A crossover randomized controlled trial

OBJECTIVE

To compare the conventional alginate impression and the digital impression taken with an intraoral scanner of both dental arches in children, using a randomized crossover design.

TRIAL DESIGN

This is a monocentric, controlled, superiority, randomized, crossover, open study.

METHODS

Twenty-four orthodontic patients between 6 and 11 years of age underwent intraoral scanning (TRIOS 3; 3Shape) and alginate impression of both dental arches with an interval of 1 week between the two procedures. Participants were recruited from September 2021 to March 2022 and the study was completed in April 2022. Impression time for the two procedures was compared. Patients were asked which one of the two impression procedures they preferred. A questionnaire including Visual Analogue Scale (VAS) for comfort, pain, gag reflex and difficulty in breathing, was administered to the patients.

RESULTS

Eighteen out of 24 patients preferred digital impression (75%, 95% confidence interval [CI]: 55% to 88%; P = .014). Scanning time was significantly shorter than alginate impression time (difference -118 seconds; 95% CI: -138 to -99; P < .001). Comfort was significantly higher for digital impression (difference 1.7; 95% CI: 0.5 to 2.8; P = .007). There was no difference in pain (difference -0.2; 95% CI: -1.5 to 1.0; P = .686) while gag reflex and breathing difficulties were smaller for digital impression (gag reflex difference -2.5; 95% CI: -4.0 to -0.9; P = .004 and breathing difficulties difference -1.5; 95% CI: -2.5 to -0.5; P = -.004).

CONCLUSIONS

Digital impression is preferred by children aged 6-11 years and it is significantly faster in acquisition time than conventional alginate impression.

REGISTRATION

The study was registered on ClinicalTrials.gov with registration number NCT04220957 on January 7th, 2020 (https://clinicaltrials.gov/ct2/show/NCT04220957).

Observation of universal Hall response in strongly interacting Fermions

The Hall effect, which originates from the motion of charged particles in magnetic fields, has deep consequences for the description of materials, extending far beyond condensed matter. Understanding such an effect in interacting systems represents a fundamental challenge, even for small magnetic fields. In this work, we used an atomic quantum simulator in which we tracked the motion of ultracold fermions in two-leg ribbons threaded by artificial magnetic fields. Through controllable quench dynamics, we measured the Hall response for a range of synthetic tunneling and atomic interaction strengths. We unveil a universal interaction-independent behavior above an interaction threshold, in agreement with theoretical analyses. The ability to reach hard-to-compute regimes demonstrates the power of quantum simulation to describe strongly correlated topological states of matter.

Selection Effects and COVID-19 Mortality Risk after Pfizer vs. Moderna Vaccination: Evidence from Linked Mortality and Vaccination Records

Prior research generally finds that the Pfizer-BioNTech (BNT162b2) and Moderna (mRNA1273) COVID-19 vaccines provide similar protection against mortality, sometimes with a Moderna advantage due to slower waning. However, most comparisons do not address selection effects for those who are vaccinated and with which vaccine. We report evidence on large selection effects, and use a novel method to control for these effects. Instead of directly studying COVID-19 mortality, we study the COVID-19 excess mortality percentage (CEMP), defined as the COVID-19 deaths divided by non-COVID-19 natural deaths for the same population, converted to a percentage. The CEMP measure uses non-COVID-19 natural deaths to proxy for population health and control for selection effects. We report the relative mortality risk (RMR) for each vaccine relative to the unvaccinated population and to the other vaccine, using linked mortality and vaccination records for all adults in Milwaukee County, Wisconsin, from 1 April 2021 through 30 June 2022. For two-dose vaccinees aged 60+, RMRs for Pfizer vaccinees were consistently over twice those for Moderna, and averaged 248% of Moderna (95% CI = 175%,353%). In the Omicron period, Pfizer RMR was 57% versus 23% for Moderna. Both vaccines demonstrated waning of two-dose effectiveness over time, especially for ages 60+. For booster recipients, the Pfizer-Moderna gap is much smaller and statistically insignificant. A possible explanation for the Moderna advantage for older persons is the higher Moderna dose of 100 μg, versus 30 μg for Pfizer. Younger persons (aged 18-59) were well-protected against death by two doses of either vaccine, and highly protected by three doses (no deaths among over 100,000 vaccinees). These results support the importance of a booster dose for ages 60+, especially for Pfizer recipients. They suggest, but do not prove, that a larger vaccine dose may be appropriate for older persons than for younger persons.

Three-dimensional comparison of bone-borne and tooth-bone-borne maxillary expansion in young adults with maxillary skeletal deficiency

OBJECTIVE

To compare the transverse dental and skeletal changes in patients treated with bone-anchored palatal expander (bone-borne, BB) compared to patients treated with tooth and bone-anchored palatal expanders (tooth-bone-borne, TBB) using cone-beam computer tomography (CBCT) and 3D image analysis.

METHODS

The sample comprised 30 patients with transverse maxillary discrepancy treated with two different types of appliances: bone-borne (Group BB) and tooth-bone-borne (Group TBB) expanders. CBCT scans were acquired before (T1) and after completion of maxillary expansion (T2); the interval was 5.4 ± 3.4 and 6.2 ± 2.1 months between the T1 and the T2 scans of Group TBB (tooth-bone-borne) and Group BB (bone-borne), respectively. Transverse, anteroposterior and vertical linear and angular three-dimensional dentoskeletal changes were assessed after cranial base superimposition.

RESULTS

Both groups displayed marked transverse skeletal expansion with a greater ratio of skeletal to dental changes. Greater changes at the nasal cavity, zygoma and orbital levels were found in Group BB. A relatively parallel sutural opening in an anterior-posterior direction was observed in Group TBB; however, the Group BB presented a somewhat triangular (V-shaped) opening of the suture that was wider anteriorly. Small downward-forward displacements were observed in both groups. Asymmetric expansion occurred in approximately 50% of the patients in both groups.

CONCLUSION

Greater skeletal vs dental expansion ratio and expansion of the circummaxillary regions were found in Group BB, the group in which a bone-borne expander was used. Both groups presented skeletal and dental changes, with a similar amount of posterior palate expansion. Asymmetric expansion was observed in both groups.

Clear aligner mandibular advancement in growing patients with Class II malocclusion

Treatment effects occurring during Class II malocclusion treatment with the clear aligner mandibular advancement protocol were evaluated in two growing patients: one male (12 years, 3 months) and one female (11 years, 9 months). Both patients presented with full cusp Class II molar and canine relationships. Intraoral scans and cone-beam computed tomography were acquired before treatment and after mandibular advancement. Three-dimensional skeletal and dental long-axis changes were quantified, in which the dental long axis was determined by registering the dental crowns obtained from intraoral scans to the root canals in cone-beam computed tomography scans obtained at the same time points. Class II correction was achieved by a combination of mandibular skeletal and dental changes. A similar direction of skeletal and dental changes was observed in both patients, with downward and forward displacement of the mandible resulting from the growth of the mandibular condyle and ramus. Dental changes in both patients included mesialization of the mandibular posterior teeth with flaring of mandibular anterior teeth. In these two patients, clear aligner mandibular advancement was an effective treatment modality for Class II malocclusion correction with skeletal and dental effects and facial profile improvement.

Analysis of maxillary arch expansion in growing patients treated with early Class III protocol versus RME

Aim

To evaluate and compare the maxillary arch expansion obtained in growing patients treated with Class III early treatment protocol (the modified SEC III protocol), or rapid maxillary expansion (RME).

Methods

This retrospective observational study included patients in the mixed dentition with maxillary constriction and/ or dental crowding. The first group consisted of 30 patients (11 males and 19 females, mean age 9.4 ±1.7 years) with dentoskeletal Class III malocclusion treated with the modified SEC III protocol. The second group of 30 patients (14 males and 16 females, mean age 9.3 ±1.5 years) with Class I or II malocclusion was treated with a Hyrax-type expander applied to bands on the first upper molars. For each subject, initial (T0) and post expansion (T1) digital dental casts were collected. The intermolar and intercanine widths, the arch lengths at both cusp and gingival levels, the anteroposterior length and the palatal depth were measured at T0 and T1.

Results

At T1 there were statistically significant differences for 3-3 occlusal (OC) (P < 0.009), arch-length OC (P <0.030), anteroposterior arch-length (AP) (P <0.003), Depth (P <0.030) and Ap (P <0.000). No statistically significant T0-T1 changes were found between the modified SEC III and Hyrax groups except for Depth (P <0.011) with a mean difference of 2.3 mm between the two groups.

Conclusions

Both bonded and banded expanders, used in the modified SEC III protocol and RME treatment respectively, produced similar changes in the upper arch. The different initial dentoskeletal malocclusions of the two sample groups were not relevant to the post-expansion arch changes.

Understanding COVID-19 Vaccine Effectiveness against Death Using a Novel Measure: COVID Excess Mortality Percentage

COVID-19 vaccines have saved millions of lives; however, understanding the long-term effectiveness of these vaccines is imperative to developing recommendations for booster doses and other precautions. Comparisons of mortality rates between more and less vaccinated groups may be misleading due to selection bias, as these groups may differ in underlying health status. We studied all adult deaths during the period of 1 April 2021-30 June 2022 in Milwaukee County, Wisconsin, linked to vaccination records, and we used mortality from other natural causes to proxy for underlying health. We report relative COVID-19 mortality risk (RMR) for those vaccinated with two and three doses versus the unvaccinated, using a novel outcome measure that controls for selection effects. This measure, COVID Excess Mortality Percentage (CEMP), uses the non-COVID natural mortality rate (Non-COVID-NMR) as a measure of population risk of COVID mortality without vaccination. We validate this measure during the pre-vaccine period (Pearson correlation coefficient = 0.97) and demonstrate that selection effects are large, with non-COVID-NMRs for two-dose vaccinees often less than half those for the unvaccinated, and non-COVID NMRs often still lower for three-dose (booster) recipients. Progressive waning of two-dose effectiveness is observed, with an RMR of 10.6% for two-dose vaccinees aged 60+ versus the unvaccinated during April-June 2021, rising steadily to 36.2% during the Omicron period (January-June, 2022). A booster dose reduced RMR to 9.5% and 10.8% for ages 60+ during the two periods when boosters were available (October-December, 2021; January-June, 2022). Boosters thus provide important additional protection against mortality.

Dentoskeletal effects of clear aligner vs twin block-a short-term study of functional appliances

PURPOSE

The twin block (TB) is one of the most widely used functional appliances for the correction of class II malocclusions. Align Technology (San Jose, CA, USA) developed the Invisalign® mandibular advancement (MA) that replicates the mechanism of action of a functional appliance. The aim of this study was to compare the changes produced by the TB versus those by MA.

METHODS

The records of 56 class II patients treated with the TB (TB group: n = 35) or the MA (MA group: n = 21) were compared to a control sample of 15 untreated class II subjects (UC2).

RESULTS

The TB and MA groups showed a significant reduction of the ANB angle, compared to the controls (TB group: -1.5°; MA group: -1.5°; UC2 group: +0.2°). For the Co-Gn values, the TB and MA groups showed significant differences when compared with the UC2 group with an increase of 8.4 mm in TB patients and of 8.3 mm in MA patients. The increase of the distance of Pg to the true vertical line (TVL) was the only measurement where significant differences between the three groups were found with a greater advancement of the soft tissue pogonion in the TB group compared with the MA group and the UC2 group (TB group: +3 mm; MA group: +0.9 mm; UC2 group: -1.6 mm). The angle between the palatal plane and mandibular plane revealed a more relevant reduction in the TB and MA groups. Both appliances were able to reduce overjet and vertical overbite values.

CONCLUSIONS

Treatment with the MA and TB appliances produced a significant elongation of the mandible with an improvement in sagittal relationship, overjet, and vertical overbite and with good control of the vertical relationship. TB subjects showed a greater advancement of the soft tissue chin.

Understanding COVID-19 Vaccine Effectiveness Against Death Using a Novel Measure: COVID Excess Mortality Percentage

COVID-19 vaccines have saved millions of lives and prevented countless adverse patient disease outcomes. Understanding the long-term effectiveness of these vaccines is imperative to developing recommendations for precautions and booster doses. Comparisons between more and less vaccinated groups may be misleading due to selection bias, as these groups may differ in underlying health status and thus risk of adverse COVID-19 outcomes. We study all adult deaths over April 1, 2021-June 30, 2022 in Milwaukee County, Wisconsin, linked to vaccination records, use mortality from other natural causes to proxy for underlying health, and report relative COVID-19 mortality risk (RMR) for vaccinees versus the unvaccinated, using a novel outcome measure that controls for selection effects. This measure, COVID Excess Mortality Percentage (CEMP) uses the non-COVID natural mortality rate (Non-Covid-NMR) as a measure of population risk of COVID mortality without vaccination. We validate this measure during the pre-vaccine period (r = 0.97) and demonstrate that selection effects are large, with Non-Covid-NMRs for two-dose vaccinees less than half those for the unvaccinated, and Non-COVID NMRs still lower for three dose (booster) recipients. Progressive waning of two-dose effectiveness is observed, with relative mortality risk (RMR) for two-dose vaccinees aged 60 + versus the unvaccinated of 11% during April-June 2021, rising steadily to 36% during the Omicron period (January-June, 2022). Notably, a booster dose reduced RMR to 10-11% for ages 60+. Boosters thus provide important additional protection against mortality.

Comparison of rapid versus slow maxillary expansion on patient-reported outcome measures in growing patients: a systematic review and meta-analysis

BACKGROUND

No systematic review and meta-analysis are present in the literature comparing patient-reported outcome measures (PROMs) in rapid maxillary expansion (RME) versus slow maxillary expansion (SME) in growing patients.

OBJECTIVE

The objective of this systematic review was to compare PROMs in RME versus SME in growing patients.

MATERIALS AND METHODS

Electronic search in PubMed (MEDLINE), Cochrane Library, Scopus, Embase, Web of Science, and OpenGrey was conducted. Only RCTs were included. Inclusion criteria were: growing patients in the mixed dentition or early permanent dentition, mild-to-moderate maxillary transverse deficiency, dental crowding, treatment with fixed expanders for rapid and slow maxillary expansion. Risk of bias was assessed using RoB 2. GRADE statement was performed. The mean of the differences (MD) and the risk ratio (RR) were used for the aggregation of data. A random effect model was applied.

RESULTS

Two articles with a total of 157 patients were finally included in the systematic review and meta-analysis. One article was at low risk of bias, while one was at risk of bias with some concerns. Pain presence was less, though not statistically significant, in SME patients (RR = 2.02, 95%CI from 0.55 to 7.49, P = 0.29, I² = 95%, 2 studies, GRADE very low). Pain intensity was significantly lower in SME appliance in the first week of treatment (pooled MD = 0.86 favoring SME, 95%CI from 0.47 to 1.26, P < 0.0001, I² = 6%, 2 studies, GRADE moderate). There were no significant differences between the two groups in difficulty in speaking, difficulty in swallowing, hypersalivation, difficulty in hygiene, and patient and parent satisfaction.

CONCLUSIONS

Pain intensity was significantly lower in SME compared to RME during the first week of treatment. For the following weeks, there were no differences in pain between the two protocols.

Effects produced by the facemask with and without skeletal anchorage for the orthopaedic treatment of Class III malocclusion in growing patients: a systematic review and meta-analysis of RCTs

BACKGROUND

Skeletally anchored facemask has been proposed to maximize skeletal effects and minimize dental effects in the treatment of Class III malocclusion in growing patients.

OBJECTIVE

To compare the dento-skeletal effects produced by the facemask with or without skeletal anchorage for the treatment of Class III malocclusion in growing patients.

MATERIALS AND METHODS

PubMed, Cochrane Library, Scopus, Embase, Web of Science, and OpenGrey were used for the electronic search without language, publication status, and year restrictions. Only RCTs were included. Inclusion criteria were: growing patients (age under 18 years) with Class III malocclusion, with indications for treatment with the facemask. Data were extracted by two independent reviewers. GRADE statement was executed. The mean of differences (MD) and the risk ratio (RR) were used.

RESULTS

Three articles with a total of 123 patients were included. One article was at low risk of bias while two were at high risk of bias. There were no significant differences between the two groups in ANB angle, Wits appraisal, SNB angle, and SN-MP angle. SNA angle was significantly increased in the skeletally anchored facemask (pooled MD = 0.80 favouring skeletal anchorage, 95% CI from 0.29 to 1.31, P = 0.002, I2 = 12 per cent, three studies, GRADE moderate). The U1-SN angle was significantly reduced in the skeletally anchored facemask (pooled MD = -5.91 favouring skeletal anchorage, 95% CI from -7.64 to -4.27, P < 0.00001, I2 = 0 per cent, two studies, GRADE moderate). There were significantly less complications in tooth-anchored facemask (pooled RR = 7.98 favouring dental anchorage, 95 per cent CI from 1.04 to 61.27, P = 0.05, I2 = 0 per cent, two studies, GRADE low).

LIMITATIONS

Few RCTs (three) were included, and two studies were at high risk of bias. There were no long-term RCTs comparing skeletally anchored facemask with dental-anchored facemask. Only Asiatic patients were included in this systematic review.

CONCLUSIONS

Skeletally anchored facemask was associated to a greater increase of SNA angle at the end of treatment though clinically not significant. Facemask with skeletal anchorage determined a reduced inclination of maxillary incisors compared to dental-anchored facemask with greater risks of complications.

REGISTRATION

PROSPERO register (CRD42020221982).

Stability of fiducial cephalometric landmarks of growing Class II malocclusion patients: a three-dimensional retrospective study

OBJECTIVES

To evaluate three-dimensionally (3D) the stability of Nasion (Na), Sella (S), Basion (Ba), Porion (Po), and Orbitale (Or) in different age groups of growing Class II malocclusion patients and, additionally, to assess rotational changes of the S-Na and Ba-Na lines and the Frankfurt Horizontal Plane (FHP).

MATERIALS AND METHODS

Cone-beam computed tomography studies of 67 Class II division 1 malocclusion patients, acquired at baseline (T0) and 1 year later (T1), were retrospectively assessed. Anterior cranial fossa was used for volumetric superimposition. Subjects were grouped according to their age at T0: group 1 (G1) (8-10 years), G2 (11-13 years), and G3 (14-17 years). Quantitative assessments of the 3D linear displacements (Euclidean distance) in the position of Na, S, Ba, Po, and Or were performed. Displacement in the X, Y, and Z projections and the rotation of S-Na, Na-Ba, and FHP were also quantified.

RESULTS

All cephalometric landmarks showed 3D displacement (P = .001) in the three age groups. Orbitale remained stable in the vertical and sagittal dimension from 8 to 17 years (P > .05). S-Na, Na-Ba, and the FHP showed statistically significant angular rotation (P < .05) in younger patients (G1), while in older individuals (G2 and G3) they were stable (P > .05).

CONCLUSIONS

Na, S, Ba, and Po showed vertical and sagittal positional changes relative to the anterior cranial fossa during the growth of Class II individuals. After age 11, S-Na, Na-Ba, and FHP did not show rotation and, thus, are valid parameters for angular cephalometric analysis in Class II growing patients.

Three-dimensional evaluation of skeletal and dental effects of treatment with maxillary skeletal expansion

INTRODUCTION

The objective was to determine the skeletal and dental changes with microimplant assisted rapid palatal expansion (MARPE) appliances in growing (GR) and nongrowing (NG) patients using cone-beam computed tomography and 3-dimensional imaging analysis.

METHODS

The sample consisted of 25 patients with transverse maxillary discrepancy treated with a maxillary skeletal expander, a type of MARPE appliance. Cone-beam computed tomography scans were taken before and after maxillary expansion; the interval was 6.0 ± 4.3 months. The sample was divided into GR and NG groups using cervical vertebral and midpalatal suture maturation. Linear and angular 3-dimensional dentoskeletal changes were assessed after cranial base superimposition. Groups were compared with independent-samples t test (P <0.05).

RESULTS

Both groups displayed marked transverse changes with a similar ratio of skeletal to dental transverse changes and parallel sutural opening from the posterior nasal spine-anterior nasal spine; a similar amount of expansion occurred in the anterior and the posterior regions of the maxilla. The maxilla expanded skeletally without rotational displacements in both groups. The small downward-forward displacements were similar in both groups, except that the GR group had a significantly greater vertical displacement of the canines (GR, 1.7 ±1.0 mm; NG, 0.6 ± 0.8 mm; P = 0.02) and anterior nasal spine (GR, 1.1 ± 0.6 mm; NG, 0.5 ± 0.5 mm; P = 0.004).

CONCLUSIONS

Treatment of patients with MARPE appliance is effective in GR and NG patients. Although greater skeletal and dental changes were observed in GR patients, a similar ratio of skeletal to dental transverse changes was observed in both groups.

Dentoskeletal effects of early class III treatment protocol based on timing of intervention in children

Background

To detect the optimal timing of intervention based on different cervical vertebral maturation stage (CS1-2 vs. CS3-4) for the treatment of Class III malocclusion with early Class III protocol.

Methods

A total sample of 43 patients (23 females, 20 males) ranging between 7 and 13 years of age with dentoskeletal Class III malocclusion treated with the modified SEC III (Splints, Elastic and Chincup) protocol divided into two groups based on the cervical vertebral maturation stages (CS1-2 and CS3-4) was included in this retrospective observational longitudinal study. Patient compliance was assessed using a 2-point Likert scale. Statistical comparisons between the two groups were performed with independent sample t tests.

Results

No statistically significant differences for any of the cephalometric variables describing the baseline dentoskeletal features were found between the two groups except for the mandibular unit length that was significantly greater in the pubertal group (P = 0.005). The modified SEC III protocol produced favorable sagittal outcomes in both groups, whereas no statistically significant T1-T2 changes were found between the CS1-2 and CS3-4 groups for any of the angular and linear measurements. No significant differences were found in the prevalence rates of the degree of collaboration between the two groups (P = 1.000).

Conclusions

No significant differences between prepubertal and pubertal patients were found in the sagittal and vertical dentoskeletal changes with the modified SEC III protocol. Thus, this early Class III treatment produced similar favorable effects in growing subjects regardless of the cervical vertebral maturation stages from CS1 to CS4.

Post-pubertal effects of the Alt-RAMEC/FM and RME/FM protocols for the early treatment of Class III malocclusion: a retrospective controlled study

OBJECTIVE

To assess the stability of the effects of the modified Alt-RAMEC and facial mask (FM) protocol at a post-pubertal observation.

METHODS

Twenty-one Class III patients (11 males and 10 females, 6.5 ± 0.7 years) treated consecutively with the Alt-RAMEC/FM approach and presenting with lateral cephalograms taken before treatment (T1), after treatment (T2), and at post-pubertal observations (T3) were compared with 22 Class III patients (9 males and 13 females, 6.9 ± 1.2 years) treated with the rapid maxillary expansion (RME) and FM protocol and with 15 Class III untreated subjects (7 males and 8 females, 6.2 ± 2.2 years). At T3, all patients showed a post-pubertal skeletal maturation stage (CS4-CS6). Descriptive statistics and statistical comparisons between the three groups at T1 and for the T3-T1, T2-T1, and T3-T2 changes were assessed by means of the ANOVA or Kruskal-Wallis test.

RESULTS

During the overall observation period, Alt-RAMEC/FM and RME/FM protocols produced statistically significant favourable effects when compared with the Control group (ANB + 2.8° and +2.2°, respectively; Wits appraisal +4.4 mm and +2.7 mm, respectively). No statistically significant differences were found between the outcomes of the Alt-RAMEC/FM and RME/FM protocols neither at the post-pubertal or short-term observations.

LIMITATIONS

Retrospective study and the comparison with an historical control sample of subjects with untreated Class III malocclusion.

CONCLUSIONS

The Alt-RAMEC/FM protocol cannot be recommended as the approach of choice for the therapy of Class III dentoskeletal disharmony in very young subjects compared to the conventional RME/FM protocol.

Modified SEC III protocol: vertical control related to patients' compliance with the chincup

OBJECTIVES

To compare the short-term outcomes of modified SEC III protocol in growing patients in relation to their compliance with the chincup, matching them with an untreated Class III control group (CG).

MATERIALS AND METHODS

Thirty-four patients (mean age of 8.6 ± 1.2 years) with Class III dentoskeletal malocclusion treated with the modified SEC III protocol and divided into group 1 (G1, 18 subjects), reporting good compliance and group 2 (G2, 16 subjects) not compliant with the chincup. The records were analysed before treatment (T1) and after the orthopaedic phase (T2), with an interval period of about 1.3 ± 0.5 years. The CG consisted of 16 untreated subjects with Class III dentoskeletal malocclusion (mean age of 8.3 ± 1.4 years). The statistical comparisons among the three groups were performed with ANOVA with Tukey's post hoc tests.

RESULTS

Both G1 and G2, compared with CG, presented significant improvements in the sagittal skeletal relationships (ANB +2.5° and +2.5°, Wits +4.2° and +3.0°, respectively). G1 exhibited a significant more favourable control of vertical skeletal relationships when compared to G2 (Palatal Pl.-Mandibular Pl. -2.0°) that were associated with a statistically significant reduction of the gonial angle (ArGoMe -1.7°). Limitations of the study were its retrospective nature and the lack of evaluation of the long-term outcomes.

CONCLUSIONS

Both groups of treated patients showed favourable sagittal skeletal improvement compared with controls. The use of chincup in patients with good compliance produced significantly greater control of the skeletal vertical dimensions compared with patients not compliant with the chincup.

Variations in maxillary second molar position of untreated subjects with normal occlusions: A long-term observational study

INTRODUCTION

The purpose of the present study was to evaluate the long-term variations in maxillary second molar position in untreated subjects with normal occlusion.

SETTING AND SAMPLE POPULATION

A sample of 39 subjects (18 females and 21 males) selected from the University of Michigan Growth Study (UMGS) was followed longitudinally with digital dental casts at 3 observation times: T1, when the maxillary permanent second molars were fully erupted, T2, last observation available in the longitudinal series (38 subjects), and T3, at least 20 years after T2 (12 subjects).

MATERIALS AND METHODS

Digital measurements were recorded with an open-source software. Outcome variables were sagittal and transverse inclinations of the upper second molars. Two mixed-effect models were performed.

RESULTS

The maxillary second molars had a distolingual inclination at T1, T2 and T3. Sagittal and transverse inclination showed progressive significant uprighting from T1 through T3 (P < .001). From T1 to T2, the adjusted difference in sagittal crown inclination was 8.0° (95% CI from 6.5° to 9.6°; P < .001). From T2 to T3, the adjusted difference was 5.5° (95% CI from 3.0° to 8.1°; P < .001). From T1 to T2, the adjusted difference in transverse crown inclination was 1.9° (95% CI from 0.4° to 3.5°; P = .011). From T2 to T3, the adjusted difference was 6.0° (95% CI from 3.4° to 8.5°; P < .001).

CONCLUSIONS

Along with age, maxillary second molars showed a progressive significant uprighting with a decrease in the distal and lingual inclinations.

Comparison between two screws for maxillary expansion: a multicenter randomized controlled trial on patient's reported outcome measures

OBJECTIVE

The objective of this study was to compare an expansion screw of the maxilla that generates moderate and continuous forces versus a conventional screw for rapid maxillary expansion (RME) on patient-reported outcome measure during the first 12 weeks of treatment.

TRIAL DESIGN

This is a superiority, multicenter, two-arm parallel balanced randomization trial.

METHODS

Patients in the mixed dentition were included with a transverse discrepancy between the two arches of at least 3 mm. An expansion screw using moderate continuous forces (Leaf group, treated with an expansion screw with Ni-Ti springs) was compared to a conventional RME screw that generates intermittent heavy forces (RME group). The primary response variable was the visual analogue scale (VAS) on pain calculated in the first 12 weeks of therapy. The VAS on difficulty on speaking and oral hygiene, patient satisfaction, and complications were also evaluated. A computer-generated block randomization was used with allocation concealed in sequentially numbered opaque-sealed envelopes. Blinding was not applicable. Linear models were used for statistical analysis.

RESULTS

Twenty-eight patients in the Leaf group and 28 patients in the RME group were randomized and included in the study. There were no dropouts. The mean of the VAS for pain was 0.3 ± 0.4 in the Leaf group and 0.6 ± 0.5 in the RME group. The difference was -0.3 (95 per cent CI from -0.5 to -0.0; P = 0.017) in favour of the Leaf group. The difference in pain was marked in the first week (Leaf group 2.2 ± 2.3; RME group 3.7 ± 2.6; difference -1.5; 95 per cent CI from -2.7 to -0.3; P = 0.019).

CONCLUSIONS

Patients in the Leaf group experienced a lower degree of pain, especially during the first week following the application of the expander. For the other variables, no significant differences were reported between the two treatments.

REGISTRATION

The study was registered in the ISRCTN register on 8 November 2016 with the number ISRCTN18263886.

Cephalometric effects of Pushing Splints 3 compared with rapid maxillary expansion and facemask therapy in Class III malocclusion children: a randomized controlled trial

Background

Pushing Splints 3 (PS3) device was recently introduced for the treatment of Class III malocclusion in children.

Objectives

To assess the effect on the sagittal maxillary position (SNA, primary outcome) of PS3 therapy compared with rapid maxillary expansion and facemask therapy (RME/FM) and to compare skeletal and dento-alveolar effects in growing Class III patients.

Trial design

This trial was a single-centre randomized controlled trial with two groups randomly allocated in a 1:1 ratio of equal size by sealed-envelope randomization, conducted at the Dentistry Unit of Bambino Gesù Children’s Hospital, IRCCS (Rome, Italy).

Methods

A total of 48 patients with Class III malocclusion were included in the study and randomly allocated to the two groups: PS3 therapy and RME/FM therapy. Only the RME/FM group underwent palatal expansion, and both groups were instructed to wear the appliances 14 hours/day. Pre- (T0) and post-treatment (T1) cephalograms were taken. An independent sample t-test and regression analysis were used to analyse the data (P value <0.05). Researchers involved in statistics and tracings were blinded to the treatment allocation.

Results

A total of 42 patients (21 for each group) completed the study. The maxillary sagittal position improved similarly in both groups (SNA = 0.4°; P = 0.547). A statistically significant decrease of SNPg angle (−1.6°; P < 0.001) and increase of ANPg angle (1.4°; P = 0.018) were found in the RME/FM group compared with PS3 group. CoGoMe angle significantly decreased in RME/FM group compared with PS3 group (−1.7°; P = 0.042). The regression analysis showed an association between SN/MP angle at T0 and the differences between T1 and T0 of SNPg (B = 0.13; P = 0.005) and SN/MP (B = −0.19; P = 0.034). Only three patients (PS3 = 2; RME/FM = 1) had breakages of the devices.

Limitations

Results are limited to short-term effects.

Conclusion

RME/FM therapy and PS3 are both effective therapies for the early correction of Class III malocclusion. The PS3 controlled better mandibular divergency reducing the clockwise rotation in patients with higher mandibular inclination.

Registration

This study was not registered in a clinical trial registry.

Dento-skeletal effects produced by rapid versus slow maxillary expansion using fixed jackscrew expanders: a systematic review and meta-analysis

BACKGROUND

No systematic review and meta-analysis of dento-skeletal effects following rapid maxillary expansion (RME) and slow maxillary expansion (SME) using the same jackscrew expander with different activation protocols is available.

OBJECTIVE

To compare dento-skeletal effects produced by RME with those induced by SME using the same fixed jackscrew expanders in growing patients.

SEARCH METHODS

PubMed (MEDLINE), Cochrane Library, Scopus, Embase, and OpenGrey were searched with no language or publication date restrictions.

SELECTION CRITERIA

Only randomized controlled trials (RCTs) were selected and the following inclusion criteria were used: growing patients in mixed or permanent dentition, with maxillary transverse discrepancy, dental crowding, and treated with fixed jackscrew maxillary expander (e.g. Hyrax, Haas) activated to achieve either RME or SME.

DATA COLLECTION AND ANALYSIS

Data were extracted by two independent reviewers. The quality of the included RCTs was assessed according to the Cochrane risk-of-bias tool for randomized trials (RoB 2.0). For the aggregation of continuous data, the mean of the differences (MD) between treatments was used. A random effect model was applied.

RESULTS

From 4855 retrieved articles, 3 studies were selected, 1 at unclear risk and 2 at high risk of bias. Maxillary intermolar distance showed no significant differences between the two modalities of expansion [pooled MD = 0.99 mm favouring RME, with 95% confidence interval (CI) = -2.09 to 4.06, P = 0.53, I2 = 90%]. As for maxillary molar inclination measured as the angle formed by the axes passing through the disto-buccal cusps and the apexes of the palatine root of the first upper molars, it was significantly smaller in the SME group (MD = -11.51°, with 95% CI = -15.23 to -7.79, P < 0.0001). Posterior maxillary expansion was significantly greater in RME than SME (pooled MD = 0.75 mm, with 95% CI = 0.27-1.23, P = 0.002, I2 = 0%).

CONCLUSIONS

Both RME and SME produce an effective dento-skeletal expansion of the maxilla. RME is slightly more effective in increasing the posterior transverse skeletal width of the maxilla while SME induces smaller molar inclination.

REGISTRATION

PROSPERO CDR42018105530.

Comparison of the dento-skeletal effects produced by Leaf expander versus rapid maxillary expander in prepubertal patients: a two-center randomized controlled trial

OBJECTIVE

This study aimed to compare the skeletal and dentoalveolar effects produced by slow maxillary expansion (SME) with the Leaf expander versus the conventional rapid maxillary expansion (RME) on digital dental casts, lateral and postero-anterior cephalometric radiographs.

TRIAL DESIGN

This is a superiority, two-center, two arms parallel balanced randomization trial.

METHODS

Patients in the mixed dentition were included with a transverse interarch discrepancy of at least 3 mm. An expansion screw using moderate continuous forces (Leaf group) was compared to a conventional RME screw (RME group). The primary response variable was the difference in maxillary intermolar width (U6-U6) measured at baseline (T0) and one-year follow-up (T1) on the digital dental casts. Other dento-skeletal variables were also measured on digital dental casts and cephalograms. Computer-generated block randomization was used with allocation concealed in sequentially numbered opaque sealed envelopes. The examiner was blinded on the type of expander used. Linear models were used for statistical analysis.

RESULTS

Twenty-eight patients in the Leaf group and 28 patients in the RME group were randomized and included in the study. There were no dropouts. U6-U6 did not show a statistically significant difference between the two groups (-0.4 mm in favor of the RME group, 95% CI from -1.2 to 0.5, P = 0.365). As for the other secondary variables no statistically significant differences were found between the two groups except maxillary intercanine width (U3-U3, -0.9 mm in favor of the RME group, 95%CI from -1.5 to -0.3, P = 0.005) and maxillary skeletal width (Mx-Mx, -1.4 mm in favor of the RME group, 95%CI from -2.4 to -0.3, P = 0.013).

CONCLUSIONS

No significant differences between the RME and Leaf groups were detected for any of the analyzed dento-skeletal variables except the T1-T0 differences in U3-U3 and Mx-Mx that were significantly greater in the RME group.

REGISTRATION

The study was registered in the ISRCTN register on 08/11/2016 with the number ISRCTN18263886.

FUNDING

No funding or conflict of interest to be declared.

Treatment of mild Class II malocclusion in growing patients with clear aligners versus fixed multibracket therapy: A retrospective study

Objective

To compare the dental and skeletal effects of intermaxillary elastics on the correction of mild Angle's Class II division 1 malocclusion with clear aligner treatment (CA) versus fixed multibracket (FMB) in growing patients.

Settings and sample population

The study sample consisted of 49 consecutively patients (mean age ± SD 12.9 ± 1.7 years), 32 females and 17 males referred from the School of Orthodontics of the University of Bratislava Comenius (Slovakia). All patients were treated with a non‐extraction orthodontic treatment, 25 with FMB and 24 with CA.

Methods

The cephalometric analysis was performed at the beginning (T0) and the end of the treatment (T1). The t test for unpaired data was carried out to compare cephalometric values at T0 and changes at T1‐T0 between the two groups. The level of significance was set as P < .0035.

Results

The two groups showed no statistically significant differences (ANPg = −0.1°; P = .762) in the correction of the sagittal intermaxillary relation. The analysis of vertical skeletal changes showed no statistically significant effects on mandibular inclination (SN/MP = 0.1°; P = .840). The two treatments had a statistically significant and clinically relevant difference in controlling the inclination of the lower incisors (L1/GoGn = 4.8°, CAG = −0.5°± 3.9°; FMB = 4.3°± 5.8°; P < .001).

Conclusions

Class II elastics combined with CA and FMB produce a similar correction on sagittal discrepancies in growing patients. CA presented a better control in the proclination of the lower incisors. CA and elastics might be a good alternative in the correction of mild Class II malocclusion in cases where a proclination of lower incisors is unwanted.

Predicting the mandibular growth spurt

OBJECTIVES

To develop a prediction model that combined information derived from chronological age, sex, and the cervical vertebral maturation (CVM) method to predict the pubertal spurt in mandibular growth.

MATERIALS AND METHODS

A total of 50 subjects (29 females, 21 males) were selected from the American Association of Orthodontists Foundation Craniofacial Growth Legacy Collection, the University of Michigan Growth Study, and the Denver Child Growth study. A total of 456 lateral cephalograms were analyzed, and a multilevel logistic model was applied. The outcome variable was the presence or absence of the mandibular pubertal growth peak. The predictive variables were chronological age up to the third order, sex, presence or absence of CS 3 interactions between age and sex, age and CS 3, sex and CS 3.

RESULTS

The mean age ± standard deviation (SD) at the first cephalogram was 8.2 ± 0.5 years, whereas the mean age at the last cephalogram was 16.5 ± 1.1 years. The mean interval ± SD between two consecutive cephalograms was 1.0 ± 0.1 years. The mean age ± SD at the lateral cephalogram obtained immediately before the mandibular pubertal growth peak was 12.1 ± 1.1 years for females and 13.2 ± 0.8 years for males. The greatest increase in mandibular length occurred after CS 3 in 78% of the subjects. The presence of CS 3, age, second-order age, sex, and the interaction between age and sex were all statistically significant predictors of the mandibular pubertal growth spurt.

CONCLUSIONS

CS 3, chronological age, and sex can be used jointly to predict the pubertal peak in mandibular growth.

Regenerative Endodontic Therapy using a New Antibacterial Root Canal Cleanser in necrotic immature permanent teeth: Report of two cases treated in a single appointment

A case of regenerative endodontics: (a) before treatment; (b) post-treatment Xray; (c) follow-up at 6 months; (d) follow-up at 12 months.

Soft tissue evaluation of functional therapy in growing patients with Class II malocclusion: a long-term study

OBJECTIVE

The objective of this study was to analyse the soft tissue changes produced by the functional treatment of mandibular advancement in growing Class II patients.

MATERIALS

The treated group consisted of 25 Caucasian patients (12 females and 13 males) with dento-skeletal Class II malocclusion treated with functional therapy (Activator). All patients were evaluated before treatment (T1; mean age, 9.9 years), at the end of functional treatment phase (T2; mean age, 11.9 years), and at a post-pubertal follow-up observation (T3; mean age, 18.5 years). The treated group was compared with a matched control group of 25 untreated subjects (13 females, 12 males) with untreated Class II division 1 malocclusion. Statistical comparisons between the two groups were performed with independent samples t-tests (P < 0.05).

RESULTS

Significant improvements were found during the long-term interval for mandibular sulcus (9.9°) and the profile facial angle (9.8°) in the treated group. No significant effects were found in terms of lower face percentage between the two groups.

CONCLUSION

Removable functional appliances induced positive effects on the soft tissue profile in Class II growing subjects with good stability in the long-term.

Evaluation of adolescent and adult patients treated with the Carriere Motion Class III appliance followed by fixed appliances

OBJECTIVES

To determine dentoalveolar and skeletal effects produced in mature patients by the Carriere Motion Class III (CM3) appliance followed by fixed appliances.

MATERIALS AND METHODS

This retrospective study evaluated 32 patients at three time points: T1 (initial), T2 (removal of CM3), and T3 (posttreatment). Serial cephalograms were traced and digitized, and best-fit regional superimpositions were constructed. Eleven linear and 7 angular variables were measured. The starting forms of the CM3 patients were compared with a sample of untreated subjects with normal occlusions and well-balanced faces.

RESULTS

The CM3 phase lasted 6.3 months, followed by a phase of fixed appliances lasting 12.9 months; the total duration of treatment was 19.2 months. Minimal skeletal changes were measured sagittally, with only a slight increase in lower anterior facial height observed during treatment. Most treatment changes were dentoalveolar in nature. Wits appraisal increased 4.0 mm during treatment. The molar relationship improved by 6.0 mm during phase I, a value that rebounded slightly during phase II, resulting in an improvement toward Class I of 4.8 mm. Best-fit regional superimpositions revealed anterior movement of upper molars relative to the maxilla and posterior movement of lower molars relative to the mandible.

CONCLUSIONS

The Carriere Motion Class III appliance is an effective and efficient method of resolving occlusal problems in minimally growing Class III patients. Primary treatment effects are dentoalveolar in nature with minimal skeletal alterations.

Prognostic approach to Class III malocclusion through case-based reasoning

OBJECTIVE

This investigation evaluates the evidence of case-based reasoning (CBR) in providing additional information on the prediction of future Class III craniofacial growth.

SETTINGS AND SAMPLE POPULATION

The craniofacial characteristics of 104 untreated Class III subjects (7-17 years of age), monitored with two lateral cephalograms obtained during the growth process, were evaluated.

MATERIALS AND METHODS

Data were compared with the skeletal characteristics of subjects who showed a high degree of skeletal imbalance ('prototypes') obtained from a large data set of 1263 Class III cross-sectional subjects (7-17 years of age).

RESULTS

The degree of similarity of longitudinal subjects with the most unbalanced prototypes allowed the identification of subjects who would develop a subsequent unfavourable skeletal growth (accuracy: 81%). The angle between the palatal plane and the sella-nasion line (PP-SN angle) and the Wits appraisal were two additional craniofacial features involved in the early prediction of the adverse progression of the Class III skeletal imbalance.

CONCLUSIONS

Case-based reasoning methodology, which uses a personalized inference method, may bring additional information to approximate the skeletal progression of Class III malocclusion.

Predicting mandibular growth based on CVM stage and gender and with chronological age as a curvilinear variable

OBJECTIVE

The aim of this study was to develop a prediction model that combines the information derived from chronological age (analysed as a curvilinear variable), gender and the CVM method to predict mandibular growth.

SETTINGS AND SAMPLE POPULATION

50 participants (29 females, 21 males) were selected from the AAOF Craniofacial Growth Legacy Collection, the Michigan Growth Study and the Denver Child Growth study.

MATERIALS AND METHODS

In this investigation, 456 lateral cephalograms were analysed by applying a mixed effect model. The outcome variable was the annualized increment in total mandibular length (Co-Gn) during the year following the lateral cephalogram on which the cervical stage and chronological age were evaluated. The predictive variables were chronological age up to the fifth order, gender, stage of cervical vertebral maturation, as well as interactions between age and gender, age and cervical stage, and gender and cervical stage.

RESULTS

Cervical stage, chronological age up to the fourth order, gender, and the interaction between age and gender were significant predictors of annualized increments in mandibular length. The annualized increment in Co-Gn was significantly greater for CS 3 when compared to all other cervical stages. Further, annualized increments in Co-Gn for CS 1 and CS 2 were significantly greater when compared to CS 5.

CONCLUSIONS

Cervical stage, chronological age and gender can be used jointly to predict the annualized increment in mandibular growth. Cervical stage 3 exhibited the greatest annualized increase in mandibular length.

Comparison of two protocols for early treatment of dentoskeletal Class III malocclusion: Modified SEC III versus RME/FM

OBJECTIVE

To compare the short-term cephalometric outcomes of the protocols modified splints, Class III elastics, chincup (SEC III) and rapid maxillary expansion and facial mask (RME/FM) for the early treatment of growing subjects with Class III dentoskeletal malocclusion.

SETTINGS AND SAMPLE POPULATION

This retrospective observational study included 20 patients (11 males, nine females) treated with the modified SEC III protocol and 31 patients (16 males, 15 females) treated with the RME/FM one. The sample was evaluated before (T1, mean age 7.9 ± 1.0 years) and at the end of treatment (T2, mean age 9.0 ± 1.0 years). Statistical comparisons between the two groups were performed with independent sample t tests.

RESULTS

Both the modified SEC III and the RME/FM sample groups showed significantly favourable effects in terms of maxillary advancement (SNA +1.3° and +1.5°, respectively), control of mandibular projection (SNB -0.5° and -0.8°, respectively), and intermaxillary relationships (ANB +1.8° and +2.3°, respectively; Wits +3.4 and +1.9 mm, respectively). The modified SEC III group showed a statistically significant greater control in the intermaxillary divergency considering the SN to Pal. Pl. (P < 0.006) and Pal. Pl. to Mand. Pl. angle (P < 0.002) with a difference of 2.3 mm between the two groups.

LIMITATIONS

The main limitations of this study are its retrospective nature and the short-term outcomes.

CONCLUSION

Early treatment of growing patients with dentoskeletal Class III disharmonies is efficient using either modified SEC III or RME/FM protocols. However, a higher vertical control is achieved with the modified SEC III.

Interceptive use of pendulum for advance resolution of class II patient: a guided eruption plan to reduce stress on permanent teeth root

Use of the so-called distalizing mechanics is a common treatment to correct class II malocclusion. One of the first appliances made for molar distalization was the pendulum, which resulted immediately efficient. The knowledge of pendulum efficacy, in regards to distalizing treatment in adolescence, has guided the research to analyze pendulum effect in childhood: checking the pre-eruptive, natural and distal movement of upper second premolar following first upper molar distalization in order to obtain an advance resolution on Angle's Class II patient, limited treatment time, reduced periodontal inflammation and stress on permanent teeth root. A pilot study testing the possibility of a prospective study was necessary on 6 patients treated following an accurate protocol (6 months and 1-year Rx control) and 6 patient control after one year. Statistical analysis by T-Test was done. Oral hygiene controls every month were done. Second upper bicuspid vertical (1.6mm) and sagittal (2.5mm) movement mean values allow to emphasize a distal variation of tooth axis inclination of treatment group than control group, and a second upper bicuspid distal departure from "gubernaculus dentis" of second deciduous molar in treated patients. Periodontal inflammation appears inexistent on second and first upper premolar germs after the comparison between RX exam of treatment and control groups because of exploiting deciduous teeth. Besides periodontal inflammation and teeth root stress on first upper molar of treatment group, after RX analysis, results were limited compared to control groups because of the advanced orthodontic interceptive treatment during a previous stage of first upper molar root development.

Computer-aided heuristics in orthodontics

INTRODUCTION

During the decision-making process, physicians rely on heuristics that consist of simple, useful procedures for solving problems, intuitive shortcuts that produce reliable decisions based on limited information. In clinical situations characterized by a high degree of uncertainty such as those encountered in orthodontics, cognitive biases and judgment errors related to heuristics are not uncommon. This study aimed at promoting trust in the effective interface between the intuitive reasoning of the orthodontic practitioner and the computational heuristics emerging from simple statistical models.

METHODS

We propose an integrative model based on the interaction between clinical reasoning and 2 computational tools, cluster analysis and fast-and-frugal trees, to extract a structured craniofacial representation of untreated subjects with Class III malocclusion and to forecast the worsening of the malocclusion over time.

RESULTS

Cluster analysis of cephalometric values from 144 growing subjects with Class III malocclusion followed longitudinally (T1: mean age, 10.2 ± 1.9 years; T2: mean age, 13.8 ± 2.7 years) produced 3 morphologic subgroups with predominant sagittal, vertical, and slight maxillomandibular imbalances. Fast-and-frugal trees applied to different subgroups extracted heuristics that improved the prediction of key features associated with adverse craniofacial growth.

CONCLUSIONS

Provided that cephalometric values are placed in the appropriate framework, the matching between simple and fast computational approaches and clinical reasoning could help the intuitive logic, perception, and cognitive inferences of orthodontic practitioners on the outcome of patients affected by Class III disharmony, decreasing errors associated with flawed judgments and improving the accuracy of decision making.

Cephalometric outcomes of a new orthopaedic appliance for Class III malocclusion treatment

OBJECTIVE

To evaluate dental and skeletal effects of a new orthopaedic appliance for the treatment of Class III malocclusion in growing patients.

MATERIAL AND METHODS

This retrospective cephalometric study was performed on a sample of 18 patients with a skeletal Class III malocclusion (4 males; 14 females; mean age 8.8 ± 1.5 years) treated with the Pushing Splints 3 (PS3) protocol. The control group consisted of 18 subjects (5 males; 13 females; mean age 9.1 ± 1.8 years) selected from a database of subjects with untreated Class III malocclusion. The cephalometric analysis was performed at the beginning (T0) and the end of the orthopaedic therapy (T1). Significant differences between the treated and control groups were assessed with independent samples t-test (P < 0.05).

RESULTS

In the PS3 group, the post-treatment cephalometric values showed a forward displacement of the maxilla, resulting in a statistically significant increase of the SNA angle. ANPg and Wits appraisal improved significantly compared with the control group. Lingual inclination of mandibular incisors and buccal inclination of the upper incisors were significantly increased in comparison with the control group. No significant differences were recorded for backward mandibular rotation.

LIMITATIONS

This study presents a short-term evaluation of the treatment and the use of a historical control group.

CONCLUSIONS

The PS3 was effective for the treatment of Class III malocclusion in growing patients, with favourable maxillary advancement and control of the vertical skeletal relationships.

The fence technique: Autogenous bone graft versus 50% deproteinized bovine bone matrix / 50% autogenous bone graft-A clinical double-blind randomized controlled trial

OBJECTIVES

The aim of this short-term double-blind, parallel, randomized clinical trial was to compare bone augmentation grafting with 100% autogenous bone (AB) or 50% deproteinized bovine bone matrix (DBBM)/ 50% autogenous bone (BOAB) using a guided bone regeneration procedure, the fence technique, in a two-stage implant placement.

MATERIAL AND METHODS

Partially edentulous patients with extensive three-dimensional osseous defects were included in this study. The main outcome measure was the differences in bone volume from pre-surgery (T1) to 6 months post-surgery (T2). Bone height, chair-time, pain, functional limitation, and complications were also assessed.

RESULTS

Fifteen patients were allocated to the AB group and 15 patients to the BOAB group. The difference in bone volume from T1 to T2 was 648 mm³ for the AB group and 869mm³ for the BOAB group (difference between groups 221 mm³ , 95% CI from -363 to 804, p = .442). The surgery pain VAS was 1.6 for the AB group and 2.3 for the BOAB group (difference between groups 0.8, 95% CI from 0.0 to 1.5, p = .045 favoring the AB group). The height difference in bone from T1 to T2 was 2.2 mm for the AB group and 3.7 mm for the BOAB group (difference between groups 1.5mm, 95% CI from 0.1 to 2.9, p = .038 favoring the BOAB group). For complications, chair-time, post-surgery pain, and functional limitation, there were no differences between AB and BOAB.

CONCLUSIONS

No significant differences, except for surgery pain VAS and difference in bone height, were observed in this trial comparing grafting with AB or BOAB.

Geometric morphometric analysis of the palatal morphology in growing subjects with skeletal open bite

OBJECTIVES

To assess the morphological shape variations of the palatal vault in Open Bite (OB) growing subjects when compared with a Control Group (CG) by means of Geometric Morphometric Method (GMM).

MATERIALS AND METHODS

The OB Group (OBG) consisted of 75 subjects (39 females, 36 males; mean age: 8.5 ± 0.8 years) who were collected retrospectively with the following inclusion criteria: European ancestry, overbite less than 0 mm, mixed dentition stage, prepubertal skeletal maturation (CS1-CS2), hyperdivergent skeletal pattern (SN^GoGn > 37°). The OBG was compared with a CG of 46 prepubertal subjects presenting normal occlusion (24 females, 22 males; mean age of 8.3 ± 1.7 years). For each subject, lateral cephalograms and maxillary dental casts were available. Landmarks and semilandmarks were digitized on digital dental casts and GMM was applied. Procrustes analysis and principal component analysis (PCA) were performed. OBG was divided in two subgroups: Sucking Habits Group (SHG) (39 subjects) and Non-Sucking Habits Group (NSHG) (36 subjects).

RESULTS

PC1 showed significant morphological changes in transverse and vertical dimensions with OBG palates higher and narrower when compared with CG. When comparing the two subgroups no statistically significant differences were found. NSHG demonstrated a slight reduction of the transverse dimension and a deeper palatal vault respect to SHG.

LIMITATIONS

The limitations of this study were the division of OBG in two subgroups based on referral of thumb sucking habits without assessing the duration and the intensity of thumb sucking.

CONCLUSIONS

OB subjects presented with a significant constriction of the maxillary arch when compared with CG. The morphological palatal shape variations in OBG were not influenced by the presence or absence of non-nutritive sucking habits.

Evaluation of the morphometric covariation between palatal and craniofacial skeletal morphology in class III malocclusion growing subjects

Background

To study the covariation between palatal and craniofacial skeletal morphology in Class III growing patients through geometric morphometric analysis (GMM).

Methods

In this retrospective study, 54 Class III subjects (24F,30M;7.6 ± 0.8yy) were enrolled following these inclusion criteria: European ancestry, Class III skeletal and dental relationship, early mixed dentition, prepubertal skeletal maturation, familiarity for Class III malocclusion, no pseudo Class III malocclusion. Each patient provided upper digital cast and cephalogram before starting the therapy. Landmarks and semilandmarks were digitized (239 on the casts;121 on the lateral radiographs) and GMM was used. Procrustes analysis and principal component analysis (PCA) were applied to show the principal components of palatal and craniofacial skeletal shape variation. Two-block partial least squares analysis (PLS) was used to assess pattern of covariation between palatal and craniofacial morphology.

Results

Regarding palatal shape variation, PC with largest variance (PC1) described morphological changes in the three space dimensions, while, concerning the craniofacial complex components, PC1 revealed morphological differences along the vertical plane. A significant covariation was found between palatal and craniofacial shape. PLS1 accounted for more than 61,7% of the whole covariation, correlating the craniofacial divergence to palatal height and width.

Conclusions

In Class III subjects increments of angle divergence are related to a narrow and high palate.

Dentoskeletal effects of the maxillary splint headgear in the early correction of Class II malocclusion

Background

To compare dentoskeletal changes produced by the maxillary splint headgear and cervical headgear appliance during the early phase of Class II treatment, specially the initial overjet and upper incisors position.

Subjects and methods

In this retrospective study, 28 Class II patients treated with the maxillary splint headgear (MSG, mean age 10.1 ± 1.9 years) and 28 Class II patients treated with cervical headgear (CHG, mean age 9.5 ± 1.9 years) were evaluated before and after treatment. Statistical comparisons between the two groups for cephalometric measurements at T1 and for T2-T1 changes were performed by means of independent sample t tests.

Results

The MSG showed a significantly greater reduction of the overjet in comparison to the CHG (− 2.4 mm and − 0.7 mm, respectively) and a significantly greater maxillary incisor uprighting (− 1.8 mm and 0.4 mm, respectively). In the MSG, overjet correction was due mainly to mandibular advancement (3.5 mm), while the correction of molar relationship (3.9 mm) was 64% skeletal and 36% dentoalveolar. In the CHG, the overjet correction was also more skeletal, due to mandibular growth (1.8 mm), while correction of molar relationship (3.5 mm) was 63% dentoalveolar and 37% skeletal.

Conclusions

Both groups showed favorable skeletal mandibular changes, which was more significant in the MSG. Regarding tooth movement, the maxillary splint headgear was more effective in uprighting upper incisors and reducing the overjet than cervical headgear appliance.

Evaluation of sagittal airway dimensions after face mask therapy with rapid maxillary expansion in Class III growing patients

OBJECTIVE

The aim of this investigation was to analyze the effects of RME and FM on the airway dimensions in Class III patients compared with untreated controls.

METHODS

A sample of 47 Class III patients treated with RME and FM was analyzed. The treated group was compared with 18 untreated controls. Lateral cephalograms for each patient at T1, T2, and T3 were digitized.

RESULTS

At long-term evaluation a significant increase in airway size and a significant decrease in adenoid size were found in the treated group as well as an improvement in the pharynx dimension. During active treatment the treated group showed a significant improvement in lower airway size and in lower pharynx dimension. A significant decrease in adenoid size was also found.

CONCLUSION

The treatment with RME and FM produced favorable stable changes in the airway dimensions in Class III subjects when compared with untreated controls.

Imaging of mandibular fractures: a pictorial review

Mandibular fractures are among the most common maxillofacial fractures observed in emergency rooms and are mainly caused by road accidents. The clinical features of mandibular fractures include malocclusion and loss of mandibular function. Panoramic radiography is usually limited to isolated lesions, whereas computed tomography is the tool of choice for all other facial traumatic events. No reference standard classification system for the different types of mandibular fractures is defined. Therapeutic options include a conservative approach or surgical treatment based on the anatomic area and the severity of fracture. The main purpose of this pictorial review is to illustrate a practical description of the pathophysiology of mandibular fractures and describe both the imaging techniques to recognise them and the therapeutic indications.