Anthropometry is defined as the science that deals with measuring dimensions of the human body with characteristics related to head and face for nose, eyes in addition to ears and their use in various fields such as normal growth studies, clinical aspects, and maxillofacial treatment including surgery [6, 16].
Owing to simplicity and low risk, anthropometry is a biologically important tool that provides objective unique data about craniofacial scale evaluation throughout a series of correlated head and face measures.
Based on their crucial role in shaping population specificity that describes genetic/ environmental influences, it was a matter of prime interest.
Our study was conducted on 3080 Egyptian healthy preschool children of both sexes (between 3 and 6 years old) with exclusion criteria; (chronic diseases, any syndromes or genetic abnormality, any facial deformity). Our study showed detailed measurements of the middle third of the face including (eye measures, ear measures, and nose measures). Our results showed eye measurements with insignificant differences between males and females. Also, nasal and ear measurements showed an insignificant difference in males and females. All these data were put on Z-score charts of both males and females within normal values (+ 2:− 2). From these measures, we can know normal ranges in age of 3–6 years so that we can detect any deviation from normal and deal with accordingly based on best clinical practice.
Differences with most publications in respect to older age group, percentile representation of results besides that not all of the studied measures were assessed make comparison difficult. Here, charts for z-score were used at which regularly intervened age was plotted on the x-axis against the corresponding parameter to be measured at Y-axis as shown in associated figures.
In the present study, eye measurements in the participating children aged from 3 to 6 years showed no significant difference; p > 0.05. Mean values of inner canthus distance (ICD) ranged from 2.8 to cm. The mean of outer canthal distance (OCD) ranged from 7.6 to 8.2 cm and that of inter-pupillary distance (IPD) ranged from 4.9 to 5.3 cm, these findings were in-line with Oladipo et al., who showed that mean of inner canthal distance (ICD) of Nigerian children ranged from 3.08 to 3.14 cm and mean of outer canthal distance (ICD) ranged from 8.5 to 8.8 cm . Also, our results were following Azeem et al., who found that means of inner canthal distance (ICD), outer canthal distance (ICD), and inter-pupillary distance (IPD) in cm ranged from 2.7 to 2.8 cm, from 7.7 to 8.1 cm and from 4.9 to 5.3 cm, respectively, with no significant difference between males and females with p-value > 0.05 . Osunwoke et al., similarly found that the mean of inner canthal distance (ICD), outer canthal distance (ICD), and inter-pupillary distance (IPD) of another study on Nigerian children ranged from 2.3 to 2.5 cm, from 7.9 to 8.6 cm and from 4.8 to 5.3 cm, respectively, with no significant difference between both sexes . Another similar finding was evident in a study on Iranian children which reported mean values of inner canthal distance (ICD) ranged from 2.91 to 2.92 cm with a p-value of 0.9, outer canthal distance (OCD) ranged from 7.5 to 7.7 cm with a p-value of 0.01 and inter-pupillary distance (IPD) ranged from 4.9 to 5.05 cm with no significant sex difference .
In our study, the mean of eye palpebral fissure length ranged from 2.5 to 2.7 cm which was in agreement with Raffa et al., who showed that mean of palpebral fissure length in Swedish children in age 4–6 y was 2.4 cm in both sexes with no significant difference between them . In a study on Indian children in age groups between 2–5 years, similar results were obtained as shown by mean values of inner canthal distance (ICD), outer canthal distance (ICD) and inter-pupillary distance (IPD) ranged from 2.7 to 2.8 cm, from 7.7 to 9.2 cm and from 4.7 to 5.1 cm in order with a p-value of non-significance .
Comparative results between white (Asians and Americans) and black children in a study by Pivnick et al.  on normal values of mean inner canthal distance (ICD), outer canthal distance (OCD), and inter-pupillary distance (IPD) revealed that these measures in black children ranged from 2.9 to 3.2 cm, from 8 to 8.8 cm and from 5.4 to 6 cm which was larger than white children whose values ranged from 2.6 to 2.8 cm, from 6.6 to 7.5 cm, and from 4.6 to 5.1 cm, respectively, with a highly significant difference between the two races (p < 0.001).
Racial differences, geographical distribution, and genetic interplay factors were considered for these results variations.
Regarding the nasal measurements among our studied participants, the nonsignificant sex differences in mean values of 2.7 to 3.5, 2.7 to 3.0 cm, and 1.21 to 1.39 cm in this corresponding order for nasal length, nasal width, and nasal protrusion (cm), p > 0.05 came following Hegazy et al.  who found that nasal length and width of healthy Egyptian subjects of both sexes in the age group of 1–5 years ranged from 3.2 to 3.3 cm and 2.2 to 2.4 cm, respectively. Also, these findings were in-line with Winaikosol et al.  who reported in a study about children, aged 4–7 years, in northeast Thailand that means of nasal width was 3.08 cm and the nasal tip height was 1.31 cm. Similarly, Goto et al.  on Dutch children’s study who aged 0.5–7 years showed mean nasal length, nasal width and nasal protrusion (cm) ranged from 3.7 to 3.8 cm, from 2.92 to 2.96 cm and from 1.44 to 1.50 cm in order.
However, the above-mentioned findings were discordantly higher than a study report of Sforza et al.  on Italian children at age ranges between 4 and 6 y with mean values of nasal bridge length ranging from 2.6 to 2.7 cm and alar base width ranging from 2.2 to 2.4 cm, whereas, the mean of nasal tip protrusion ranged from 1.4 to 1.42 cm which was in agreement with our study findings in both boys and girls.
Speaking about the mean of columella length and width (cm) in both of the studied boys and girls, the values ranged from 0.5 to 0.63 cm and from 0.4 to 0.63 cm, respectively, with no significant difference between both sexes which was concordant with the results of Winaikosol et al. .
As for the ear measurements in the present study, the following measures were assessed; the ear length, ear width, and ear projection with their corresponding values ranged from 4.6 to 6.1 cm, from 2.6 to 3.2 cm, and from 3.10 to 3.25 cm, respectively, for both sides (RT and LT ear) in both males and females in the age group of 3–6 years with a difference of non-significance between both sexes; (p value > 0.05).
This agreed with EL-Faresy et al.  who found that the mean of ear length, width and ear projection (cm) on healthy Egyptian children aged 4–7 years ranged from 5.1 to 5.5 cm, from 3.02 to 3.11 cm, and from 3.10 to 3.14 cm of both sides of ear, respectively, with no significant difference between them, p-value > 0.05, and this was concordant with Purkait, et al., who found that means of ear length and width on Indian children in the age from 3 to 5 years ranged from 5.06 to 5.24 cm and from 3.09 to 3.21, respectively, in both of included two sex groups . Sforza et al., report within a study on healthy white Italians aged 4–5 years. The mean of ear length, ear width, and ear projection ranged from 5.03 to 5.33 cm, from 2.95 to 3.41 cm, and from 3.12 to 4.31 cm of both sides of the ear, respectively, in both boys and girls .
Speaking about a study of Kalcioglu et al., who found that the mean of ear length and width in normal Turkish children aged 3–5 years ranged from 5.09 to 5.43 and from 2.51 to 2.67 cm on the right side of the ear, respectively, with no significant difference between males and females p-value > 0.05 except in age of 4 years p-value < 0.05 and this disagreed with our study at which those children had mean values of ear projection at ranges between 1.64 to 1.84 cm which was lower than our findings with no significant difference between both ears (p-value > 0.05) except in age of 5 years p-value < 0.05 .
Concerning the mean of ear position in children aged 3–6 years was within normal average except 0.6–1% with low normal sitting ear position with no significant difference between both sexes, which may favor our explanation that it could be a familial genetic pattern with normal variation. This agreed with EL-Faresy et al., study on healthy Egyptian children aged 4–5 years to detect position of both right and left ear; p value of > 0.05 . Refusal to take all measurements by some children and some children were afraid from the instruments were challenges during our study. The relatively small sample size and lack of certified international references to use in a comparison were limitations in our study.
Finally, it was about past decades since these measures were assessed with little clarification upon z-score application so, we think that more studies with timely re-evaluation and comparative analysis are needed to establish anthropometric measurements of a mid-face zone in both males and females in Egypt that help prompt early recognition of deviation from normal and accordingly deal with.