Rugae Pattern Research Articles

Genetic variants in bone morphogenetic proteins signaling pathway might be involved in palatal rugae phenotype in humans

This study investigated, if genetic variants in BMP2, BMP4 and SMAD6 are associated with variations in the palatal rugae pattern in humans. Dental casts and genomic DNA from 75 patients were evaluated. Each patient was classified as follows: total amount of rugae; bilateral symmetry in the amount, length and shape of the palatal rugae; presence of secondary or fragmentary palatal rugae; presence of unifications; predominant shape; and predominant direction of the palatal rugae. The genetic variants in BMP2 (rs1005464 and rs235768), BMP4 (rs17563) and SMAD6 (rs2119261 and rs3934908) were genotyped. Genotype distribution was compared between palatal rugae patterns using the chi-square test (alpha = 0.05). The allele A was associated with the presence of secondary or fragmentary rugae for rs1005464 (OR = 2.5, 95%CI 1.1–6.3; p = 0.014). Secondary or fragmentary rugae were associated with the G allele in rs17563 (OR = 2.1, 95%CI 1.1–3.9; p = 0.017). rs17563 was also associated with rugae unification (p = 0.017 in the additive model). The predominant shape (wavy) was associated with rs2119261 (p = 0.023 in the additive model). The left–right symmetry of the length of primary rugae was associated with rs3934908 in the recessive model (OR = 3.6, 95%CI 1.2–11.7; p = 0.025). In conclusion, genetic variants in the BMP pathway impacted on palatal rugae pattern.

Comparitive analysis of palatal rugae in tribal and urban population of Madhya Pradesh

Human identification is a major task undertaken in forensic sciences. The study of palatine rugae and the study of fingerprints are sometimes complementary and based on same scientific basis.The palatal rugae patterns are unique to every individual and are protected by the lips, buccal pad of fat and teeth. This study was conducted to examine shape and pattern of palatal rugae between tribal population and urban population of M.P state. : The study sample consisted of 60 subjects, 30 each from tribal(Gond) and urban population of Madhya Pradesh, in the age group ranging from 18 to 25 yrs. The impression of maxillary arch was obtained from each subject using alginate impression material and cast were made. The rugae were delineated on the cast using a sharp graphite pencil under adequate light and magnification and recorded according to classification given by Thomas and Kotze (1983). : After analyzing the rugae patterns in both the groups and between the 2 sides of the palate, the wavy pattern was found to be predominant followed by curved, straight, unification, circular, and nonspecific in decreasing order in the overall population. There was an obvious difference between the Rugae shapes in tribal (gonds) and urban population of Bhopal city. No significant difference in number of rugae between right and left sides between the primary and secondary rugae patterns were observed. : The pattern of rugae was seen different in these ethnic groups. In the present study, significant difference exists between the rugae patterns in tribals and urban population of M.P.

Association of Morphological Characteristics of Palatal Rugae Pattern with Dental Malocclusion in Himachal Population

Introduction: Palatal rugae used for the evaluation of dental movements and as a landmark in the superimposition of dental cast for orthodontic purpose as it is a stable point. So, the aims and objectives of our study is to investigate the association of morphological characteristics of palatal rugae with dental malocclusion in Himachali population. Materials and methods: 90 subjects divided into three groups (n=30 each) on the basis of Angle’s classification. Palatal rugae were marked on dental casts and evaluated for length, pattern and orientation. Obtained measurements were then statistically analysed. Conclusion: Primary palatal rugae’s length was found more in Class II followed by Class III and Class I malocclusion. Among the pattern of the primary palatal rugae, curved pattern were more evident on both right and left sides of all malocclusion groups. Horizontal directed orientation is more predominant on the right side and posteriorly directed on the left side of the first primary palatine rugae. Keywords: Rugae, Malocclusion, orientation pattern, length, morphology.

Effect of Dentures on Palatal Rugae: An Investigation

Aims: The aim of this study is to evaluate the rugae pattern changes (rugae number, length, shape, direction, and unification) in completely edentulous patients treated with complete denture. Materials and Methods: A total of 100 subjects were selected for the study. The experimental group comprised 60 participants (30 males and 30 females) who had undergone complete denture treatment and the control group comprised 40 participants (20 males and 20 females) who were dentulous and patients with fixed partial denture treatment. Mucostatic maxillary alginate impressions were made for all the subjects, and casts were poured with gypsum. Patients were recalled at the regular intervals of 1, 6, and 18 months after the treatment. During those recalls, the same impression procedure was made, and all the palatal rugaes were observed for number, length, shape, direction, and unifications under magnifying lens. Changes in the palatal rugae were statistically analyzed using the unpaired t‑test. Results: A gradual decrease in the length was observed in primary, secondary, and fragmentary rugae for the experimental group after denture wearing (Group 1). Statistically, the change was significant (P < 0.001) in primary rugae only. A slight change in rugae shape was also observed in the experimental group after 18 months period of denture wearing which is statistically insignificant (P > 0.05). Conclusions: Significant decrease in primary rugae length in complete denture wearers was due to sustained mechanical stress posed by the dentures on palatal rugae. The other parameters such as rugae number, direction, and unification remained constant throughout the study. Palatal rugae analysis may not be helpful for human identification in complete denture wearers. Nevertheless, palatal rugae may serve as an adjuvant to other techniques such as DNA analysis and finger prints in forensic investigations.

PATTERNS OR PREDICTION? USE OF CALCORRUGOSCOPY AS AN INDICATOR OF PERIODONTAL HEALTH.

Background: Calcorrugoscopy is the macroscopic analysis of the rugae patterns present on patients' casts made of dental stone. Aim: The present cross-sectional study was undertaken to nd the correlation between rugae pattern and periodontitis for prediction of individuals prone to periodontitis. Materials And Methods: The study population consisted of 200 Subjects who were selected in the age group of 35-44years and grouped as 100 with healthy periodontium and 100 with chronic periodontitis. Rugae patterns were photographed and impression casts were fabricated. The casts were subjected to calcorrugoscopy and were statistically analysed. Results: The number of rugae were found to be more in normal healthy individuals as compared to those having chronic periodontitis. Conclusion: The differences in the number and shape of rugae patterns in normal healthy individuals and those with periodontitis may be attributed to the disease progression.

A Comparative Analysis of Palatal Ruga Patterns among Gorkha and North-East Indian Population

Background: Palatal rugae are resistant to changes due to trauma or aging. Ruga patterns, being unique to each individual, are valuable for personal identification. The study aims to assess the applicability of palatoscopy for differentiation amongst North-east Indians and Gorkhas in India. Materials and Methods: Sample comprised a total of 100 subjects divided into two groups of 50 each for Gorkha (Group I) and North-east Indian (Group II) population. Alginate impressions were made and models were obtained. Data was recorded after tracing palatal rugae on models. Analysis of rugae for number, side- wise distribution, shape, length, and direction was undertaken. Statistical analysis was carried out and probability value was obtained. Results: After analyzing the rugae patterns in both the groups, total number of rugae was more in Group I as compared to Group II. Total number of rugae on right and left sides each was more in Group I than in Group II. The curved pattern was found to be predominant in both groups. Divergent rugae were predominant in both groups. Maximum rugae were primary and were forwardly directed. Statistical analysis revealed no significant differences between groups for parameters assessed. Conclusion: Palatoscopy independently was not able to differentiate between individuals of the two test populations. Palatoscopy may assist in the identification process in conjunction with cheiloscopy and intraoral photography. Palatoscopy, on the account of its stability and easy reproducibility, should be encouraged among dentists for maintenance of patient records for forensic identification.

Shape and Unification Pattern of Palatal Rugae as a Race Identification Tool- A Cross-Sectional Study

Background: One of the integral parts of forensic medicine is identification of individuals from biologicalsamples and from the anatomical signatures. Identification of individuals, races, species, gender from theanatomical signatures of teeth and oral cavity is one of such branches which existed in practice in crudeform even before origin of the Forensic odontology as a specialization. Individual variations in Palatal rugaepattern, and its biometric value as a potential tool for establishment of identity was reported centuries back. It’snot standardised or included in the regular standard protocols even today in the age of artificial intelligence.In this pilot study we are comparing two racial groups i.e., Indian and Malaysian with established parametersfor palate rugae with an objective of testing feasibility and validation for identification of individuals andracial groups and also to provide preliminary data for larger studies.Aims and Objectives: The aim of this pilot study is to explore the feasibility of palate rougoscopy as a toolfor race identification by studying the shape and unification Pattern of Palatal Rugae in Indian and Malaysianpopulation.Methodology: Study population was male Indian and Malaysian Medical and Dental students, aged 18-25years studying at Mangalore, India. Sample size 80 (40 in each group); were selected for studying PalatalRugae. The palate impressions were collected using maxillary alginate cast. The parameters assessed were:shape an unification based on classification of Thomas & Kotze. Comparison for two populations was doneusing non-parametric Mann-Whitney Test.Results : Predominant Shape: The Curvy patterns were more common in Malaysians compared to Indian.The Wavy patterns were more common in Malaysians than Indians.The Circular patterns were more commonin Indians than Malaysians.Predominant unification: Diverging patterns were more in Malaysians than Indians and Converging patternswere more in Indians than Malaysians and statistically significant.Conclusion : In the present study the Malaysians had predominantly curvy and wavy patterns and Indianshad circular shapes. Straight patterns were seen equally in both the populations. Although unification ofthe palate rugae was seen, the diverging patterns is more in Malaysians and Converging patterns more inIndians.

Comparison of Palatal Rugae Pattern among Indian and Malaysian Population

Background: Tools for establishing identity is invaluable part of forensic sciences form the beginningof the profession. Odontology is one of such branches which in early days started in its crude form withidentification of different species and races within the species, currently is an individual subject withspecialist societies, journals and courses. Palatal rugae, was identified to be a potential tool for establishingidentity few centuries back itself but is not validated even today to be part of standard protocols. This is apilot study comparing two racial groups i.e., Indian and Malaysian with established parameters for palaterugae aiming at testing the feasibility of the parameters to be used in identification of individuals and racialgroups and also to provide preliminary data to make way to larger studies.Aims and Objectives: The aim of this pilot study is to explore the feasibility of palate prints as tool foridentification by, studying palate print in Indian and Malaysians and Comparison of plate Rugosity betweenIndians and Malaysians students for identification.Methodology: Study population was male Indian and Malaysian Medical and Dental students, age between18-25 years studying at Mangalore, India. Sample size 80 (40 in each group); were selected for studying ofPalatal Rugae. The palate impressions were collected using maxillary alginate cast. The parameters assessedwere: Total number of rugae, number of primary rugae (length- 5 to 10 mm), secondary rugae (3-5mm),fragmentary rugae (less than 3 mm). Comparison for two populations was done using non-parametric MannWhitney Test.Results: There were no statistically significant differences among the Indians and Malaysians in totalnumber and number secondary rugae in both sides more in Indians than Malaysians.There was statistically significant difference in number of the primary rugae and the fragmentary rugae,which in both sides were more in Indians than Malaysians.Conclusion: In conclusion, palatal rugae pattern are unique to an individual and their use in forensicidentification has been advocated and applied. Our study demonstrated significant difference in the numberof primary rugae on each side. It was more in Indians than Malaysians. This study demonstrated theuniqueness of rugae pattern in different individuals. Thus, it appears to be an effective & reliable source ofidentification.

Stability of Palatal Rugae after Rapid Maxillary Expansion

Introduction: Palatal rugae or plicae palatine are uneven ridges made of connective tissue situatedbeneath the incisive papilla. DNA analysis, finger prints analysis, are the most common techniques usedfor establishing person’s identity but in situation where using these techniques are difficult palatal rugaecan be used as a second source of identification. However, some habits like prolonged thumb sucking andorthodontic treatment for long duration could affect the rugae pattern. Hence, this study aims to evaluate thechanges in transverse dimensions of palatal rugae in subjects treated with rapid maxillary expansionMaterial and Methods: The palatal rugae patterns were measured and compared to evaluate the morphometricchanges between pre-treatment cast (30 Pre-RME) and its post-treatment (30 Post-RME) counterpart. Allpre-and post-expansion dental casts were traced and the intermedial and interlateral dimensions of first,second and third rugae were measured. The statistical analysis was done using paired t test.Conclusion: The medial aspect of first primary rugae can be considered as a stable reference landmarkwhile the lateral and medial aspects of the 2nd and 3rd rugae are liable to changes in transverse dimension.Hence, for forensic identification the stability of palatal rugae in patients who had undergone rapid maxillaryexpansion still remains questionable

Subjective and Quantifiable Analysis of Palatal Rugae Pattern in Punjab Population

Abstract 
 Background: - Palatal Rugae are irregular, asymmetric ridges of mucous membrane extending laterally from incisive papillae and anterior part of palatal raphe. Palatal rugae patterns are relatively unique to individuals and are well protected by lips, buccal pad of fat and teeth.
 Aims & Objectives: - The aim of the study was to identify pattern of palatal rugae in terms of number, size, and shape and also to compare rugae patterns in males and females of Punjab population.
 Materials & Methods: - A total of 280 maxillary casts that were randomly collected and were examined using graphite pencil and magnifying glass under adequate light with equal number of males & females. Statistical analysis was done by T-test using SPSS software version 20.
 Results: - The mean rugae were found to be more in females than males. Most prevalent form on basis of shape is found to be straight and on basis of size is primary form. Statistically, significant values were found in curved and secondary type, both more in females than males.
 Conclusion: - Palatal rugae pattern is definitely a sufficient characteristic to discriminate between the genders. The present study highlighted the prevalence of palatal rugae in individuals of Punjab population. It is unique to an individual and can be used successfully in identification.

Sex Assessment by Morphological Analysis of Palatal Rugae Patterns in a South Indian Adult Population

BackgroundPalatal rugae are asymmetric and irregular ridges on the anterior palatal region, which have proven to be useful in the field of forensic dentistry. This study aims to use morphological analysis of palatal rugae patterns to assess sex in a South Indian adult population.Materials and MethodsThis cross-sectional study was undertaken to evaluate a total of 300 maxillary dental casts (150 males and 150 females). The rugae patterns were marked by one observer and classified as per Thomas and Kotze criteria by another observer. The rugae patterns were classified based on the total number of rugae, shape, predominant direction of rugae, and unification of rugae.ResultsThe palatal rugae in female participants showed a higher incidence of circular rugae and backward directed rugae, while male participants showed more forward-directed rugae. The logistic regression analysis showed a significant association of with circular (OR=1.48; 95% CI= 1.02–2.13), forward (OR=0.87; 95% CI= 0.78–0.97) and backward (OR=1.23; 95% CI= 1.08–1.41) palatal rugae with sex.ConclusionCertain palatal rugae patterns can be used for the assessment of sex with limited accuracy.

English

BACKGROUND Palatine rugae are small transverse structures present in the anterior 2 / 3rd of the palate. These rugae are protected by various structures of the oral cavity. They are immovable structures but variations in the oral cavity may lead to alterations in these small structures. There have been many studies that have quoted changes in these rugae patterns with various tooth movements whereas various other studies demonstrate no significant changes. None of the studies in specific have mentioned about palatal rugae changes with myofunctional appliances. The objective of this research was to evaluate the palatal rugae morphology and its stability after myofunctional therapy, as expansion and movement of teeth might lead to changes in these rugae. METHODS A total of 90 maxillary casts, 30 of Class I, 30 of Class II pre-treatment and casts of same subjects after myofunctional therapy, patients age ranging between 10 and 13 years were selected for the study. Length, intermedial and interlateral distances, angle of divergence and position of rugae were studied based on Lysell Classification 1955 and Thomas and Kotze Classification 1983. RESULTS Secondary and fragmentary rugae were found to be statistically significant as they were increased in Class II samples compared to Class I. The rugae in Class II samples were found to be shorter and therefore significant results were seen. IM1, IM2, IM4, IM5 and IM6 were found to be statistically significant respectively. Similarly, IL2, IL4, IL5 and IL6 were appreciable. IM1 was found to be appreciable. IL1, IL2, IL3 and IL4 were statistically significant. Significant difference was found in mean rugae value among Class I and Class II pre-treatment groups. Statistically significant difference was found in mean rugae value among Class I and Class II pre-treatment group. Incisive papilla to posterior border of last rugae (IP-PBA) was found to be statistically significant. CONCLUSIONS Myofunctional therapy did have an effect on the rugae pattern. But the age group of 10 – 13 years consisted of growing individuals. Therefore, it could not be concluded as to whether the changes were because of growth taking place or because of myofunctional therapy. KEY WORDS Palatine Rugae, Myofunctional Appliances, Class II Malocclusion

دراسة نمط الغضون الحنكية و استعمالها في التعرف علي الجنس والعرق في عينة من المصريين و الماليزيين البالغين

Background: Palatal rugoscopy is the use of palatal rugae for identification of unknown persons. The majority of the population in Egypt consists of Egyptian people. However, some Malaysian people live in Alexandria city of Egypt for the purpose of education. So in case of mass disaster, there is a critical need for a reliable and easy method to differentiate between Malaysians and Egyptians. Aim: Study palatal rugae patterns in two diverse populations; Egyptians and Malaysians and its relation to sex and population difference. Subjects: Eighty students of Alexandria Faculty of Dentistry; forty Egyptians (20 females and 20 males) and forty Malaysians (20 males and 20 females). The age ranged 18-30 years. Results: Significant difference was noted between Malaysian males and females according to total number of rugae on both sides. Malaysians had significantly higher total rugae number on both sides than Egyptians. Curved shape was the predominant shape in the total sample. Significant difference was detected between Egyptians and Malaysians according to the predominant palatal rugae direction on both left and right sides. Egyptian females had significantly higher percentage of absent unification than Egyptian males. Linear regression models for sex and ethnicity identification were built up.

Differences of Palatal Rugae Patterns between Chinese and Indian Female

Palatal rugae are irregular protrusions that are anatomically located on the anterior maxillary mucous membrane, on each side of the median palatal raphe next to the posterior incisor papilla. The aim of this research was to determine the differences of palatal rugae pattern between Chinese and Indian females. This study was descriptive by using the observation method to a total of 50 female samples consisted of 30 Chinese and 20 Indian using purposive sampling. Impressions of the upper jaws were taken and cast with dental stone. The palatal rugae pattern was identified according to Martin dos Santos classification. The most frequent palatal rugae pattern in Chinese females is curve form (41.00%), followed by line form (23.85%) and sinuous form (15.90%). On the other hand, Indian females mostly have sinuous form (28.83%), followed by line form (23.93%) and curve form (20.25%). Thus, there is a difference between palatal rugae pattern between Chinese and Indian females which is the curve forms is more common in Chinese females while the sinuous forms is more common in Indian females.

Prediction of Mandibular Growth Pattern Using Palatoscopy: A Retrospective Model Analysis

To predict and correlate mandibular growth pattern using palatoscopy (average, horizontal, and vertical). This retrospective study includes 120 archived maxillary casts. One key person and two examiners performed the study; the key person was responsible for coding and collecting casts and radiographs, as well as calibration of the examiners. The key person divided the samples into three craniofacial growth pattern groups (average, horizontal, and vertical) based on Frankfort-mandibular plane angle (FMA), SN-GoGn, and facial axis angle and distributed them to the blinded examiners. Rugae were studied using a modified Thomas and Kotze classification system. After the analysis, the results were decoded and analyzed with the corresponding cephalometric radiographs. Multinomial logistic regression was employed to predict the mandibular growth patterns with the following independent variables: Forwardly directed rugae, number of divergent rugae, predominant shape circular, predominant shape curved, primary rugae, predominant shape wavy, number of convergent rugae, and horizontally directed rugae. Palatal rugae patterns predict the growth pattern of the mandible. Considering the significant parameters and their correlation with mandibular growth pattern, prediction of mandibular growth patterns can be done noninvasively.

Rugoscopy in human identification: a study in a sample of twins

ABSTRACT Palatal rugae patterns can be useful for forensic identification purposes. However, some doubts persist in concerning the pattern singularity in twins. The purpose of this study was to assess palatal rugae pattern singularity in a sample of twins. To do this, the palatal rugae patterns of 19 pairs of monozygotic twins and 47 pairs of dizygotic twins were studied. Our results showed that in monozygotic twins, no statistical significant differences were found, either in the form or number of palatal rugae. However, in dizygotic twins, differences were found in the number or shape of all palatal rugae (except for the shape of the first two right ones), suggesting that the palatal rugae pattern can be useful for identification purposes of dizygotic, but not of monozygotic, twins.

Tooth Morphometry and Pattern of Palatal Rugae Among Monozygotic Twins in Malaysia

Introduction: Monozygotic (MZ) twins share the same DNA, placenta, amniotic fluid, and physical features. Genetic factors play a prominent role compared to environmental factors in one’s physical appearance, including dental morphology. Here we studied variation in MZ twin’s tooth morphometry and palatal rugae pattern. Materials and methods: Variation between twins can be a valuable tool in forensics to identify individuals. Ten pairs of MZ twins were selected for this research. The maximum coronal mesiodistal and buccopalatal dimension of the maxillary teeth, excluding the second and third molars, were measured in triplicate using calipers. Palatal rugae patterns of the samples were cast, analyzed, and recorded based on shape and unification. Results: Our results showed a significant tooth dimension correlation between MZ twins. Maxillary central incisors had the least genetic variability, but the Carabelli trait, skeletal pattern, occlusion, and occlusal features all exhibited a greater correlation in MZ twins. Our findings provide compelling evidence for mirroring of dental features and palatal rugae patterns in MZ twins. This study is the first of its kind reported in Malaysia. Conclusion: Marked similarities in tooth morphometry and other dental physical features were observed between twins, which can be a useful tool in forensics for the identification of individuals.

Pola Rugae Palatina pada Populasi Osing

This study aims to describe the palatal rugae pattern based on the Kapali classification in the Osing population. The research method used in this research is descriptive observational. The results showed that the simple frequency distribution of the palatine rugae pattern in the Osing population was 45.6% curved, 28.3% wavy, 8.7% circular, and 17.4% straight. In conclusion, the variation in the palatine rugae based on the Kapali classification can be shown from this study's results on the Osing population.
 
 Keywords: Kapali Classification, Forensic Odontology, Osing Population, Rugae Palatina

Anthropometric analysis of palatal rugae pattern, face form and arch form among Indian population at Moradabad, India

Purpose: To evaluate the correlation between the palatal rugae pattern, face form and arch form among Indian population at Moradabad, India. Materials and Methods: Alginate impressions of maxillary arch was made and cast was poured immediately with type III dental stone. A sharp graphite pencil was used for marking outline of the rugae on the cast. A digital caliper was employed for measurement of length of palatal rugae. Palatal rugae were analysed in accordance with Thomas and Kotze classification. Arch form of these models was determined with using 3M Unite template. For assessment of the face form, the subjects were seated in an upright position on the operator chair and the camera was stabilized on a tripod. Then photographs of the frontal profile were taken. These photographs were used for the analysis of the face form. The data was subjected to one way analysis of variance test and Post Hoc test. Results: The average number of primary rugae (10.76%) were found to be more predominant than secondary (2.12%) and fragmentary rugae (1.54%). The most predominant shape of palatal rugae were curved (42.19%) followed by wavy (32.71%), straight (17.37%) and circular (0.92%). Based on the direction of the rugae, forward rugae (54.27%) were found more common followed by backward rugae (37.26%) and perpendicular rugae (0.55%). Base on the unification of rugae pattern, diverging rugae (4.55%) were found to be more common than the converging rugae (1.57%). The most common face form was ovoid (72.4) % followed by tapered (24.4%) and square (3.2%). The most prevalent arch form was ovoid (62.2%) seen followed by the tapered (26.0%) and square (4.8%) arch form. It was found that there was significant correlation between the face form and arch form among the study subjects (p0.05). In term of arch form and face form, ovoid was the most common followed by tapered and square. Conclusion: Within the limitations of this study, it was concluded that there was significant correlation

Palatal rugae morphology is associated with variation in tooth number

This observational study compared palatal rugae morphology in adolescent subjects with normal tooth number and tooth agenesis. Maxillary dental study casts were used to compare rugae number, length and shape. Each study group contained 60 subjects (30 females and 30 males) mean age 13.4 (SD, 1.55) in control and 13.56 (SD, 1.54) years in tooth agenesis groups (p = 0.576). Mean number of missing tooth units in the tooth agenesis group was 2.1. Mean number of primary rugae in the whole sample was 4.35 (SD, 0.98) on the right and 4.33 (SD, 0.92) on the left with no significant differences (p = 0.236 and p = 0.404, respectively). However, the number of secondary rugae on the left (p = 0.006) and fragmentary rugae on the right (p = 0.004) was significantly increased in the tooth agenesis group. The shape of left primary rugae 2 and 3 also differed between groups, tending towards a wavy pattern in the control group and curved in the tooth agenesis group (p = 0.012 and p = 0.004, respectively). In addition, primary rugae 3 was more convergent (p = 0.008) whilst left primary rugae 3 and 5 were orientated in an antero-posterior direction (p = 0.04 for both rugae) in the tooth agenesis group. Subgroup analysis also identified significant associations between patterns of tooth agenesis and rugae number, in addition to shape of primary rugae. The identification of significant differences in rugae pattern between subjects with normal tooth number and agenesis suggests potential commonality in signal pathway disruption during establishment of these structures.