Three‐dimensional analysis of the occlusal plane related to the hamular–incisive–papilla occlusal plane in young adults

Abstract

The planes which serve as references for cranium and face in dental clinical application included the occlusal plane, Frankfort plane, Camper's plane and hamular-incisive-papilla (HIP) plane. The HIP occlusal plane is a horizontal plane passing through the bilateral hamular notches and the incisive papilla (Dent Surv. 1975;51:60). The aim of this study was to estimate the relationship between the various occlusal planes and the HIP plane in Taiwanese young adults with approximately optimal occlusion. Study casts of 100 young adults (50 men and 50 women) were selected in this study. All market points on the maxillary casts were measured by a three-dimensional precise measuring device. The angular relationship between the four various occlusal planes and the HIP plane were investigated. The vertical distances between the cusp tips and incisal edges of maxillary teeth to the HIP plane were measured. Data were performed by the Statistic analysis software programme (JMP 4.02). The Student's t-test and Pearson's correlation test were used to test the statistical significance (P < 0.05). The results showed that the occlusal plane defined as the incisal edge of maxillary central incisor to mesiobuccal cusp tips of maxillary second molars had the smallest included angle with the HIP plane (2.61 +/- 0.81 degrees). The incisal edge of maxillary right central incisal to mesiopalatal cusp tips of maxillary first molars had the largest included angle with the HIP plane (7.72 +/- 1.60 degrees). The curve is drawn through the buccal cusp tips of maxillary teeth had better parallelism with the HIP plane.

Relationship of Incisive Papilla to Maxillary Incisors and Canines

“…Dental casts have been used by many authors to measure the tooth dimension and distances of the landmarks in many studies and many of them have used alginate as an impression material. [7][8][9][10][11][12][13][14][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] The standardization of cast was necessary as linear measurement between two points or objects in a space would be difficult when the objects are not arranged on the same plane. In the past, studies have been done by using various methods like vernier caliper with two limbs that are adjustable with shorter and longer limbs contacting the objects at two different planes to measure the linear distance; 16 some used the contourmeter to orient the plane 21 with measuring dial guage, while Grave and Beker used Ney surveyor and vernier caliper for the same.…”

Relationship of maxillary incisors in complete dentures to the incisive papilla

“…The use of this plane also ensures that the incisive papilla and the hamular notches were on the same plane, i.e., the pterygomaxillary notch-incisive papilla (HIP) plane (8). Each cast was placed on a flat surface with the reference points touching the surface in the most stable position.…”

“…The horizontal relationship between the maxillary central incisors and the position of the incisive papilla is relatively constant. The conventional biometric guideline is 10 mm (2), with a range between 7 mm and 12-13 mm (6)(7)(8). In addition, a line connecting the tips of the maxillary canines was found to fall approximately 1 mm anterior or posterior to the center of the incisive papilla (2).…”

“…The above guidelines for the relationship of the incisive papilla to the anterior teeth depend on the ethnicity of the population studied and on whether measurements were made from the midpoint or distal surface of the incisive papilla (2,(6)(7)(8)(9). With gross resorption of the buccal plate after tooth extraction, the papilla may appear to be on the crest of the alveolar ridge, and in cases of more severe resorption it would appear to be in front of the ridge.…”

“…Another anatomic landmark that may be used in complete denture construction is the pterygomaxillary notch-incisive papilla plane, which is parallel to the occlusal plane that uses the mesiolabial incisal edge of the maxillary right central incisor as the anterior reference point and the mesiobuccal cusp tips of the maxillary first or second molars as the posterior reference point (8,10).…”