Occurrence and Predictors of Postoperative Preauricular and Masticatory Muscle Pain Symptoms After Surgical Removal of Third Molars: A Single-Blind Randomized Controlled Trial Comparing Dental Assistants Supporting the Mandible and the Restful Jaw Device.

BACKGROUND: During third molar removal, the mandible is supported by a dental assistant (DA) to counter downward forces during surgery, and with sedation, to maintain airway patency. The Restful Jaw device (PEP Design; Saint Paul) provides this support instead of the DA. PURPOSE: This study compared the occurrence of postoperative preauricular and masticatory muscle pain symptoms (PMMPS) between the device and DAs providing mandibular support, using two outcome measures. Secondary aims identify predictors of outcome and providers' opinions of the device. STUDY DESIGN, SETTING, SAMPLE: In this multisite, single-blind, two-arm parallel randomized trial, participants without preoperative PMMPS had surgical removal of third molars, with sedation and bite blocks were randomly assigned to manual support or the device. EXPOSURE VARIABLE: The exposed group was randomly assigned to the device and the nonexposed group to manual support. MAIN OUTCOME VARIABLE(S): The primary outcome was patient-reported PMMPS. Two secondary outcomes were pain assessed with the temporomandibular disorder Pain Screener and providers' views on the device. Outcomes were assessed at 1-, 3-, and 6-month postsurgery. COVARIATES: The covariates are baseline demographics (eg, sex), clinical characteristics (eg, eruption status), and third molar surgeries. ANALYSES: For occurrence of pain, generalized estimating equations assessed differences between groups. Logistic regression analysis assessed predictors of pain at 1 month, per the Screener. The level for statistical significance was 5%. RESULTS: Enrollment was 86 and 83 participants in the device and DA groups, respectively. The average age was 20.8 years; the majority were female (65%) and Caucasian (66%). The retention rate was ≥95.9%. The groups did not differ significantly for occurrence of pain using the primary and secondary outcome measures at any follow-up (P ≥ .46). Fully impacted molars were associated with occurrence of pain (odds ratio = 3.44; 95% confidence interval 1.49-7.92; P = .004). CONCLUSION AND RELEVANCE: Occurrence of pain using the primary and secondary outcome measures did not differ significantly between groups at any follow-up and was associated with removal of fully impacted third molars. Four out of five surgeons reported wanting to use the device on a regular basis when performing this procedure in sedated patients.

Exposed bone in patients with head and neck cancer treated with radiation therapy: An analysis of the Observational Study of Dental Outcomes in Head and Neck Cancer Patients (OraRad).

BACKGROUND: Patients with head and neck cancer (HNC) treated with radiation therapy (RT) are at risk for jaw osteoradionecrosis (ORN), which is largely characterized by the presence of exposed necrotic bone. This report describes the incidence and clinical course of and risk factors for exposed intraoral bone in the multicenter Observational Study of Dental Outcomes in Head and Neck Cancer Patients (OraRad) cohort. METHODS: Participants were evaluated before RT and at 6, 12, 18, and 24 months after RT. Exposed bone was characterized by location, sequestrum formation, and other associated features. The radiation dose to the affected area was determined, and the history of treatment for exposed bone was recorded. RESULTS: The study enrolled 572 participants; 35 (6.1%) were diagnosed with incident exposed bone at 6 (47% of reports), 12 (24%), 18 (20%), and 24 months (8%), with 60% being sequestrum and with 7 cases (20%) persisting for >6 months. The average maximum RT dose to the affected area of exposed bone was 5456 cGy (SD, 1768 cGy); the most frequent associated primary RT sites were the oropharynx (42.9%) and oral cavity (31.4%), and 76% of episodes occurred in the mandible. The diagnosis of ORN was confirmed in 18 participants for an incidence rate of 3.1% (18 of 572). Risk factors included pre-RT extractions (P = .008), a higher RT dose (P = .039), and tobacco use (P = .048). CONCLUSIONS: The 2-year incidence of exposed bone in the OraRad cohort was 6.1%; the incidence of confirmed ORN was 3.1%. Exposed bone after RT for HNC is relatively uncommon and, in most cases, is a short-term complication, not a recurring or persistent one.

Clinical registry of dental outcomes in head and neck cancer patients (OraRad): rationale, methods, and recruitment considerations.

BACKGROUND: Most head and neck (H&N) cancer patients receive high-dose external beam radiation therapy (RT), often in combination with surgery and/or chemotherapy. Unfortunately, high-dose RT has significant adverse effects on the oral and maxillofacial tissues, some of which persist for the life of the patient. However, dental management of these patients is based largely on individual and expert opinion, as few studies have followed patients prospectively to determine factors that predict adverse oral sequelae. In addition, many previous studies were conducted before wide-spread adoption of intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy. The objective of this multi-center study is to systematically evaluate the oral health of subjects for 2 years after commencement of RT, with the goal of identifying risk factors that predict adverse oral outcomes post-RT. METHODS: This is a prospective multi-center longitudinal cohort study of H&N cancer patients who receive high-dose RT with curative intent. Planned enrollment is 756 subjects at 6 primary clinical sites (and their affiliated sites) in the USA. A baseline visit is conducted prior to the beginning of RT. Follow-up visits are conducted at 6, 12, 18 and 24 months from the start of RT. The primary outcome measure is the 2-year rate of tooth loss in patients who have received at least one session of external beam RT for H&N cancer. Secondary outcome measures include the incidence of exposed intraoral bone; incidence of post-extraction complications; change in Decayed Missing and Filled Surfaces (DMFS); change in periodontal measures; change in stimulated whole salivary flow rates; change in mouth opening; topical fluoride utilization; chronic oral mucositis incidence; changes in RT-specific quality of life measures; and change in oral pain scores. DISCUSSION: This study will contribute to a better understanding of the dental complications experienced by these patients. It will also enable identification of risk factors associated with adverse outcomes such as tooth loss and osteoradionecrosis. These findings will support the development of evidence-based guidelines and inform the planning of future interventional studies, with the goal of advancing improvements in patient care and outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02057510 , registered 5 February 2014.

Maternal diet supplementation with methyl donors and increased parity affect the incidence of craniofacial defects in the offspring of twisted gastrulation mutant mice.

Diets rich in methyl-donating compounds, including folate, can provide protection against neural tube defects, but their role in preventing craniofacial defects is less clear. Mice deficient in Twisted gastrulation (TWSG1), an extracellular modulator of bone morphogenetic protein signaling, manifest both midline facial defects and jaw defects, allowing study of the effects of methyl donors on various craniofacial defects in an experimentally tractable animal model. The goal of this study was to examine the effects of maternal dietary supplementation with methyl donors on the incidence and type of craniofacial defects among Twsg1(-/-) offspring. Nulliparous and primiparous female mice were fed an NIH31 standard diet (control) or a methyl donor supplemented (MDS) diet (folate, vitamin B-12, betaine, and choline). Observed defects in the pups were divided into those derived mostly from the first branchial arch (BA1) (micrognathia, agnathia, cleft palate) and midline facial defects in the holoprosencephaly spectrum (cyclopia, proboscis, and anterior truncation). In the first pregnancy, offspring of mice fed the MDS diet had lower incidence of BA1-derived defects (12.8% in MDS vs. 32.5% in control; P = 0.02) but similar incidence of midline facial defects (6.4% in MDS vs. 5.2% in control; P = 1.0). Increased maternal parity was independently associated with increased incidence of craniofacial defects after adjusting for diet (from 37.7 to 59.5% in control, P = 0.04 and from 19.1 to 45.3% in MDS, P = 0.045). In conclusion, methyl donor supplementation shows protective effects against jaw defects, but not midline facial defects, and increased parity can be a risk factor for some craniofacial defects.

Tooth-level predictors of tooth loss and exposed bone after radiation therapy for head and neck cancer.

BACKGROUND: The objective of this study was to identify tooth-level risk factors for use during preradiation dental care management to predict risk of tooth failure (tooth lost or declared hopeless) and exposed bone after radiation therapy (RT) for head and neck cancer (HNC). METHODS: The authors conducted a prospective observational multicenter cohort study of 572 patients receiving RT for HNC. Participants were examined by calibrated examiners before RT and then every 6 months until 2 years after RT. Analyses considered time to tooth failure and chance of exposed bone at a tooth location. RESULTS: The following pre-RT characteristics predicted tooth failure within 2 years after RT: hopeless teeth not extracted pre-RT (hazard ratio [HR], 17.1; P < .0001), untreated caries (HR, 5.0; P < .0001), periodontal pocket 6 mm or greater (HR, 3.4; P = .001) or equaling 5 mm (HR, 2.2; P = .006), recession over 2 mm (HR, 2.8; P = .002), furcation score of 2 (HR, 3.3; P = .003), and any mobility (HR, 2.2; P = .008). The following pre-RT characteristics predicted occurrence of exposed bone at a tooth location: hopeless teeth not extracted before RT (risk ratio [RR], 18.7; P = .0002) and pocket depth 6 mm or greater (RR, 5.4; P = .003) or equaling 5 mm (RR, 4.7; P = .016). Participants with exposed bone at the site of a pre-RT dental extraction averaged 19.6 days between extraction and start of RT compared with 26.2 days for participants without exposed bone (P = .21). CONCLUSIONS: Individual teeth with the risk factors identified in this study should be considered for extraction before RT for HNC, with adequate healing time before start of RT. PRACTICAL IMPLICATIONS: The findings of this trial will facilitate evidence-based dental management of the care of patients receiving RT for HNC. This clinical trial was registered at Clinicaltrials.gov. The registration number is NCT02057510.

Tooth Failure Post-Radiotherapy in Head and Neck Cancer: Primary Report of the Clinical Registry of Dental Outcomes in Head and Neck Cancer Patients (OraRad) Study.

PURPOSE: To elucidate long-term sequelae of radiation therapy (RT) in head and neck cancer (HNC) patients, a multicenter, prospective study, Clinical Registry of Dental Outcomes in Head and Neck Cancer Patients (OraRad), was established with tooth failure as its primary outcome. We report tooth failure and associated risk factors. METHODS AND MATERIALS: Demographics and cancer and dental disease characteristics were documented in 572 HNC patients at baseline and 6, 12, 18, and 24 months after RT. Eligible patients were aged 18 or older, diagnosed with HNC, and receiving RT to treat HNC. Tooth failure during follow-up was defined as losing a tooth or having a tooth deemed hopeless. Analyses of time to first tooth-failure event and number of teeth that failed used Kaplan-Meier estimators, Cox regression, and generalized linear models. RESULTS: At 2 years, the estimated fraction of tooth failure was 17.8% (95% confidence interval, 14.3%-21.3%). The number of teeth that failed was higher for those with fewer teeth at baseline (P < .0001), greater reduction in salivary flow rate (P = .013), and noncompliance with daily oral hygiene (P = .03). Patients with dental caries at baseline had a higher risk of tooth failure with decreased salivary flow. Patients who were oral-hygiene noncompliant at baseline but compliant at all follow-up visits had the fewest teeth that failed; greatest tooth failure occurred in participants who were noncompliant at baseline and follow-up. CONCLUSIONS: Despite pre-RT dental management, substantial tooth failure occurs within 2 years after RT for HNC. Identified factors may help to predict or reduce risk of post-RT tooth failure.

Effect of neonatal capsaicin treatment on orthodontic tooth movement in male Sprague-Dawley rats.

INTRODUCTION: In this study, we examined the effect of neonatal administration of capsaicin on the magnitude of orthodontic tooth movement in rats. METHODS: Twelve timed pregnant Sprague-Dawley rats were randomized between the capsaicin group and the vehicle group. The pups received treatment with either capsaicin or vehicle on day 2 of life. Capsaicin treatment has been shown to produce a selective destruction of fine myelinated and unmyelinated Aδ and C sensory nerve fibers, causing an inhibition of the effects from neurogenic inflammation. Tooth-movement experiments began at 12 weeks of age. A mesial tipping force was applied to the maxillary first molar by using a 3-mm length of Sentalloy closed-coil spring (Dentsply GAC Intl, Bohemia, NY) activated from a bonded molar cleat to the maxillary incisors; this appliance delivers a constant tipping force of 50 g. Diastema measurements between the first and second molars were made at 2 and 4 weeks after appliance placement. Measurements were made indirectly from stone models by using a charge-coupled device microscope camera and Optimas 5.2 measurement software (Media Cybernetics, Bethesda, Md). Two-way repeated-measures analysis of variance (ANOVA) was used to analyze the differences between the groups. RESULTS: The capsaicin-treated rats and the controls did not differ in the amount of tooth movement at the collected time points (P >0.05). Similarly, the magnitude of change of tooth movement from 2 to 4 weeks did not differ between the groups (P >0.05). An increase in average diastema size was observed between 2 and 4 weeks after appliance activation in both treatment groups (P <0.0001). CONCLUSIONS: These results suggest that neonatal capsaicin desensitization in the rat does not affect the rate of orthodontic tooth movement after the application of a 50-g tipping force to the maxillary first molar. This might be due in part to the development of compensatory mechanisms in the chronically desensitized rat. Further studies are necessary to determine the reproducibility and histologic characteristics of this treatment.

Epidemiologic factors in patients with advanced head and neck cancer treated with radiation therapy.

BACKGROUND: Approximately 50% of patients with head and neck cancer (HNC) initially were seen with advanced disease. We aimed to evaluate the association of epidemiologic factors with advanced HNC at diagnosis. METHODS: The OraRad multicenter prospective cohort study enrolled HNC patients receiving curative-intent radiation therapy. Factors assessed for association with advanced HNC presentation at diagnosis included demographics, social and medical history, cancer characteristics, human papilloma virus (HPV) status, and dental disease measures. RESULTS: We enrolled 572 participants; 77% male and mean (SD) age of 61.7 (11.2) years. Oropharyngeal squamous cell carcinomas (88% HPV-related) were seen with smaller tumors, but more frequent nodal involvement. Private medical insurance and no Medicaid were associated with smaller tumors. A higher dental disease burden was associated with larger tumors. CONCLUSIONS: Insurance status, cancer type/location, and dental disease are associated with advanced HNC and may represent potentially modifiable factors or factors to be considered in the screening process of new lesions.

Treatment of periodontal disease and the risk of preterm birth.

BACKGROUND: Maternal periodontal disease has been associated with an increased risk of preterm birth and low birth weight. We studied the effect of nonsurgical periodontal treatment on preterm birth. METHODS: We randomly assigned women between 13 and 17 weeks of gestation to undergo scaling and root planing either before 21 weeks (413 patients in the treatment group) or after delivery (410 patients in the control group). Patients in the treatment group also underwent monthly tooth polishing and received instruction in oral hygiene. The gestational age at the end of pregnancy was the prespecified primary outcome. Secondary outcomes were birth weight and the proportion of infants who were small for gestational age. RESULTS: In the follow-up analysis, preterm birth (before 37 weeks of gestation) occurred in 49 of 407 women (12.0%) in the treatment group (resulting in 44 live births) and in 52 of 405 women (12.8%) in the control group (resulting in 38 live births). Although periodontal treatment improved periodontitis measures (P<0.001), it did not significantly alter the risk of preterm delivery (P=0.70; hazard ratio for treatment group vs. control group, 0.93; 95% confidence interval [CI], 0.63 to 1.37). There were no significant differences between the treatment and control groups in birth weight (3239 g vs. 3258 g, P=0.64) or in the rate of delivery of infants that were small for gestational age (12.7% vs. 12.3%; odds ratio, 1.04; 95% CI, 0.68 to 1.58). There were 5 spontaneous abortions or stillbirths in the treatment group, as compared with 14 in the control group (P=0.08). CONCLUSIONS: Treatment of periodontitis in pregnant women improves periodontal disease and is safe but does not significantly alter rates of preterm birth, low birth weight, or fetal growth restriction. (ClinicalTrials.gov number, NCT00066131 [ClinicalTrials.gov].).

Change in periodontitis during pregnancy and the risk of pre-term birth and low birthweight.

AIM: Determine whether periodontitis progression during pregnancy is associated with adverse birth outcomes. METHODS: We used clinical data and birth outcomes from the Obstetrics and Periodontal Therapy Study, in which randomly selected women received periodontal treatment before 21 weeks of gestation (N=413) or after delivery (410). Birth outcomes were available for 812 women and follow-up periodontal data for 722, including 75 whose pregnancies ended <37 weeks. Periodontitis progression was defined as >or=3 mm loss of clinical attachment. Birth outcomes were compared between non-progressing and progressing groups using the log rank and t tests, separately in all women and in untreated controls. RESULTS: The distribution of gestational age at the end of pregnancy (p>0.1) and mean birthweight (3295 versus 3184 g, p=0.11) did not differ significantly between women with and without disease progression. Gestational age and birthweight were not associated with change from baseline in percentage of tooth sites with bleeding on probing or between those who did versus did not progress according to a published definition of disease progression (p>0.05). CONCLUSIONS: In these women with periodontitis and within this study's limitations, disease progression was not associated with an increased risk for delivering a pre-term or a low birthweight infant.

Systemic immune responses in pregnancy and periodontitis: relationship to pregnancy outcomes in the Obstetrics and Periodontal Therapy (OPT) study.

BACKGROUND: Our previous studies reported on the obstetric, periodontal, and microbiologic outcomes of women participating in the Obstetrics and Periodontal Therapy (OPT) Study. This article describes the systemic antibody responses to selected periodontal bacteria in the same patients. METHODS: Serum samples, obtained from pregnant women at baseline (13 to 16 weeks; 6 days of gestation) and 29 to 32 weeks, were analyzed by enzyme-linked immunosorbent assay for serum immunoglobulin G (IgG) antibody to Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia (previously T. forsythensis), and Treponema denticola. RESULTS: At baseline, women who delivered live preterm infants had significantly lower total serum levels of IgG antibody to the panel of periodontal pathogens (P = 0.0018), to P. gingivalis (P = 0.0013), and to F. nucleatum (P = 0.0200) than women who delivered at term. These differences were not significant at 29 to 32 weeks. Changes in IgG levels between baseline and 29 to 32 weeks were not associated with preterm birth when adjusted for treatment group, clinical center, race, or age. In addition, delivery of low birth weight infants was not associated with levels of antibody at baseline or with antibody changes during pregnancy. CONCLUSIONS: Live preterm birth is associated with decreased levels of IgG antibody to periodontal pathogens in women with periodontitis when assessed during the second trimester. Changes in IgG antibody during pregnancy are not associated with birth outcomes.

Correlations between physical properties of jawbone and dental implant initial stability.

STATEMENT OF PROBLEM: There is confusion in the literature about how physical properties of bone vary between maxillary and mandibular regions and which physical properties affect initial implant stability. PURPOSE: The purpose of this study was to determine correlations between physical properties of bone and initial implant stability, and to determine how physical properties and initial stability vary among regions of jawbone. MATERIAL AND METHODS: Four pairs of edentulous maxillae and mandibles were retrieved from fresh human cadavers. Six implants per pair were placed in different anatomical regions (maxillary anterior, right and left maxillary posterior, mandibular anterior, right and left mandibular posterior). Immediately after surgery, initial implant stability was measured with a resonance frequency device and a tapping device. Implant surgeries and initial stability measurements were performed within 72 hours of death. Elastic modulus (EM) and hardness were measured using nano-indentation. Composite apparent density (cAD) was measured using Archimedes' principle. Bone-implant contact percentage and cortical bone thickness were recorded histomorphometrically. Mixed linear models and univariate-correlation analyses were used (alpha=.05). RESULTS: Generally, mandibular bone had higher initial implant stability and physical properties than maxillary bone. Initial implant stability was higher in the anterior region than in the posterior. EM was higher in the posterior region than in the anterior; the reverse was true for cAD. CONCLUSIONS: Of the properties evaluated, cAD had the highest correlation with initial implant stability (r=0.82). Both physical properties of bone and initial implant stability differed between regions of jawbone.

Effect of alendronate on orthodontic tooth movement in rats.

INTRODUCTION: Osteoclastic activity is required for orthodontic force to move teeth through alveolar bone. Bisphosphonates are drugs that inhibit osteoclast maturation, function, and survival. The aim of this study was to assess orthodontic tooth movement in rats receiving bisphosphonate treatment. METHODS: Two groups of Sprague-Dawley rats were used. The rats in the treatment group received 7 mg per kilogram of body weight per week of alendronate sodium, and those in the control group received no drugs. A coil spring exerting a constant 50-g force was activated across the span from the central incisors to the first molar. As the first molar tipped mesially, a diastema between the first and second molars was created. Vinyl polysiloxane impressions were poured in die stone, and the diastema was measured indirectly with a charged-couple device microscope camera and Optimas software (Media Cybernetics, Newburyport, Mass). RESULTS: Statistical analysis with repeated-measures analysis of variance showed less orthodontic tooth movement in the alendronate group compared with control group (0.06 vs 0.24 mm at 2 weeks, and 0.45 vs 1.06 mm at 4 weeks; P = 0.0004 for the alendronate vs control main effect). CONCLUSIONS: This study demonstrated an inhibitory effect of alendronate administration on orthodontic tooth movement in a rat model.

Modeling longitudinal spatial periodontal data: a spatially adaptive model with tools for specifying priors and checking fit.

Attachment loss (AL), the distance down a tooth's root that is no longer attached to surrounding bone by periodontal ligament, is a common measure of periodontal disease. In this article, we develop a spatiotemporal model to monitor the progression of AL. Our model is an extension of the conditionally autoregressive (CAR) prior, which spatially smooths estimates toward their neighbors. However, because AL often exhibits a burst of large values in space and time, we develop a nonstationary spatiotemporal CAR model that allows the degree of spatial and temporal smoothing to vary in different regions of the mouth. To do this, we assign each AL measurement site its own set of variance parameters and spatially smooth the variances with spatial priors. We propose a heuristic to measure the complexity of the site-specific variances, and use it to select priors that ensure parameters in the model are well identified. In data from a clinical trial, this model improves the fit compared to the usual dynamic CAR model for 90 of 99 patients' AL measurements.

Periodontal bacterial profiles in pregnant women: response to treatment and associations with birth outcomes in the obstetrics and periodontal therapy (OPT) study.

BACKGROUND: A recent clinical trial (Obstetrics and Periodontal Therapy [OPT] Study) demonstrated that periodontal therapy during pregnancy improved periodontal outcomes but failed to impact preterm birth. The present study evaluated seven target bacteria, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia (previously T. forsythensis), Prevotella intermedia, Campylobacter rectus, and Fusobacterium nucleatum, in subgingival dental plaque of pregnant women in the OPT Study and their association with birth outcomes. METHODS: Pregnant women were randomly assigned to receive periodontal treatment before 21 weeks' gestation or after delivery. Subgingival plaque was sampled at baseline (13 to 16 weeks; 6 days of gestation) and at 29 to 32 weeks. We analyzed subgingival plaque samples from women who experienced fetal loss, delivered a live preterm infant (preterm women), or delivered a full-term infant (full-term women). Samples were analyzed using quantitative polymerase chain reaction. Associations between preterm birth and bacterial counts and percentages were tested using multiple linear regression. RESULTS: No significant differences were observed at baseline between preterm and full-term women for any measured bacterial species or group of species, after accounting for multiple comparisons. Changes in bacterial counts and proportions during pregnancy also were not associated with birth outcomes. In full-term and preterm women, periodontal therapy significantly reduced (P <0.01) counts of all target species except for A. actinomycetemcomitans. CONCLUSIONS: In pregnant women with periodontitis, non-surgical periodontal therapy significantly reduced levels of periodontal pathogens. Baseline levels of selected periodontal pathogens or changes in these bacteria resulting from therapy were not associated with preterm birth.

Predicting first molar width using virtual models of dental arches.

In dentistry, large regions of dentition often are restored with minimal information about the original anatomy. The ability to predict missing anatomy from existing anatomy would aid such restorations. This study investigated the relationship between first molar mesial-distal width and arch shape using newly defined reference points and three-dimensional (3D) digital methods. Full-mouth dental stone casts from 167 dental students were scanned and rendered as 3D virtual models. Maxillary and mandibular arch lengths and widths and first molar mesial-distal widths were measured on the virtual models using new definitions incorporating virtual planes. A linear mixed model of the first molar width regressed on the other measurements was done. Intraobserver reproducibility was evaluated by means of intraclass correlation (ICC) and standard deviation of measurement error (SDME). All measured distances were averaged as a combined group and as gender groups. The correlation coefficients between the maxillary and mandibular first molar widths were over 0.70 (P < 0.01). Intraobserver error was small. ICCs were over 0.92 and SDMEs were from 0.11 to 0.21 mm. Arch dimensions and first molar widths were defined and measured. Regression equations were calculated for predicting first molar width. The prediction of first molar width using arch dimension is essential for virtual designing of missing first molars. This approach also provides reliable reference point definitions for the virtual dental model which was impossible with traditional measurement methods. Therefore, this study would be helpful for understanding the 3D anatomy of dental arch and fabrication of automatic prosthodontic restorations.

Permanent tooth development in children with cleft lip and palate.

PURPOSE: The purposes of this study were to: (1) quantify and compare permanent tooth development of cleft lip and palate (CLP) patients to age- and gender-matched controls; (2) relate these findings to cleft type and severity; and (3) examine delays in individual permanent maxillary teeth related to their proximity to the cleft. METHODS: Standardized methods using panoramic radiographs were employed to stage dental development and dental age for 49 children with clefts and 49 matched controls. Data were analyzed with a mixed linear model. RESULTS: Analyses indicated a correlation between delayed permanent tooth development and CLP with an overall delay of 0.52 years (P = .02) and with boys accounting for all the delay. No differences were found between subjects with unilateral or bilateral clefts. A nonsignificant trend was noted for greater delay in subjects with clefts of the primary and secondary palates vs primary palate alone. Teeth most often affected by the delay were maxillary first and second premolars and maxillary second molars. CONCLUSIONS: While permanent tooth development is delayed in cleft lip and palate patients, this delay is: found in boys only; is independent of the cleft type and severity; and is not correlated with proximity to the cleft.

Predictors of Long-Term Temporomandibular Disorder Pain Intensity: An 8-Year Cohort Study.

AIMS: To investigate, in individuals with pain-related temporomandibular disorder (TMD), the association of long-term pain intensity with baseline health-related quality of life (HRQoL) and jaw functional limitation. METHODS: Of 513 cases with baseline pain-related TMD (masticatory muscle and/or temporomandibular joint [TMJ] pain), 273 were reevaluated after 8 years, and 258 of them had complete baseline data for Jaw Functional Limitation Scale (JFLS) scores and HRQoL measured by the Physical Component Summary (PCS) and Mental Component Summary (MCS) scores of the 12-item Short Form Health Survey and follow-up data for Characteristic Pain Intensity (CPI) from the Graded Chronic Pain Scale. Secondary analyses of existing data quantified the effects of primary (PCS, MCS) and secondary (JFLS) predictors on follow-up CPI by using multivariable linear regression. Sensitivity analyses considered differences between the included participants (n = 258) and those who were not included (n = 255) by using inverse probability weighting. Interactions of baseline predictors with age, sex, and baseline CPI were evaluated using multivariable linear regression. RESULTS: The score for baseline PCS, but not MCS or JFLS, was associated with follow-up CPI (P = .012). One standard deviation (SD = 9.0)-higher baseline PCS score predicted an overall 3.2-point-lower follow-up CPI (95% confidence interval -5.8 to -0.7) after adjusting for age, sex, MCS, JFLS, and baseline CPI scores. However, the effect of PCS score was not uniform: the association between PCS and follow-up CPI scores was statistically significant for participants with baseline CPI ≥ 51.3/100 and clinically significant for participants with baseline CPI ≥ 68.7/100. Adjustment for TMD treatments and sensitivity analyses had negligible effect. CONCLUSION: In participants with moderate to severe baseline TMD pain intensity, higher baseline physical HRQoL predicted lower TMD pain intensity at 8 years follow-up. PCS score could contribute to a multifactorial long-term TMD pain prediction model.

Factors affecting outcomes for single-tooth implants and endodontic restorations.

Initial root canal therapy and implant placement are both common treatment modalities, and, as such, prognostic factors that influence the treatment outcomes of these two restorations should be identified. In a retrospective chart review, 196 implant restorations and 196 matched initial nonsurgical root canal treated (NSRCT) teeth in patients were evaluated for four possible outcomes-success, survival, survival with intervention, and failure. Results showed that smokers had fewer successes and more failures in both groups (p = 0.0001), whereas NSRCT outcomes were affected by periradicular periodontitis (p = 0.001), post placement (p = 0.013), and overfilling (p = 0.003). Outcomes for both groups were not significantly affected by diabetes, age, or gender. Implant group outcomes were not affected by implant length (from 10 to 16 mm), diameter (from 3.25 to 5.5 mm), or an adjacent endodontically treated tooth, nor were NSRCT outcomes affected by the number of appointments for the procedure.

The application of facial expressions to the assessment of orofacial pain in cognitively impaired older adults.

BACKGROUND: The anticipated rapid growth in the number of cognitively impaired older adults, declining edentulism and increasing oral health expectations suggest a greater need for comprehensive dental care and effective ways to evaluate orofacial pain in people with compromised mental function and impaired communication skills. The authors conducted a study to evaluate facial expressions as a means of identifying orofacial pain in cognitively impaired and cognitively intact older adults, compared with other available pain assessment tools. METHODS: The authors conducted a prospective comparative study using three alternative pain measurement tools in a sample of 22 older adults. They divided subjects into cognitively impaired and cognitively intact groups on the basis of their mental status examination scores. The pain measurement methods evaluated were facial expressions quantified by the Facial Actions Coding System (FACS); self-reported pain via the Verbal Descriptor Scale; and physiological response to pain via changes in heart rate. The pain stimuli were local anesthetic injections in subjects who required them for routine dental procedures. RESULTS: The average FACS scores during anesthetic injections were significantly higher than those during the preinjection period (prebuccal versus buccal, P = .016; prepalatal versus palatal, P = .0002). The differences between preinjection and injection segments were even higher in cognitively impaired patients than in cognitively intact patients. There were no correlations between the three pain measurements (P > .05). CONCLUSIONS: Changes in facial expression proved to be the most useful measure overall in identifying pain in both cognitively intact and cognitively impaired older patients. This measure appeared to be more sensitive in cognitively impaired patients because they demonstrated fewer facial movements in anticipation of pain stimuli.